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    PESTICIDE RESIDUES IN FOOD - 1984


    Sponsored jointly by FAO and WHO






    EVALUATIONS 1984




    The monographs



    Data and recommendations of the joint meeting
    of the FAO Panel of Experts on Pesticide Residues
    in Food and the Environment and the
    WHO Expert Group on Pesticide Residues
    Rome, 24 September - 3 October 1984

    Food and Agriculture Organization of the United Nations
    Rome 1985

    CARBOSULFAN

    IDENTITY

    Carbosulfan is a draft ISO common name

    Chemical name:           2,3-dihydro-2,2-dimethylbenzofuran-7-yl
                             (dibutylaminothio)methylcarbamate

    Chemical Abstracts Registry Number:  55285-14-8

    Company Code Number:     FMC 35001

    Structural formula:

    CHEMICAL STRUCTURE 1

    Other information on identity and properties

    Empirical formula:       C20H32N2O3S

    Molecular weight:        380.5

    Physical state:          Viscous brown liquid

    Vapour pressure:         0.3110-6 Torr

    Specific gravity:        1.056

    Solubility:

         Water               0.3 mg/l
         Xylene              >50%
         Hexane              >50%
         Chloroform          >50%
         Methylene Chloride  >50%
         Methanol            >50%
         Acetone             >50%

    Formulations

    Corrosion hazards:       none

    Storage stability:       Some emulsifiable concentrate and solid
                             formulations are said to be stable for 6
                             months at 50C, and over one year at room
                             temperature.

    Explosive hazards:       Non-explosive

    Flash point:             Above 38C (closed cup method)

    Shipping classification: Agricultural insecticide, liquid or solid.

    RESIDUES IN FOOD AND THEIR EVALUATION

    USE PATTERN

         Carbosulfan is a broad spectrum carbamate pesticide closely
    related to its main metabolite carbofuran, a major pesticide in its
    own right. Carbosulfan is available as emulsifiable concentrates,
    dusts and granular formulations (wettable powder formulations are
    under development) for the control of soil and foliar pests of a
    variety of commodities. It may be applied to soil or foliage and is
    said to be effective through direct contact or stomach ingestion.
    Foliar pests may be controlled by soil applications via systemic
    action, although as discussed under "Fate of Residues" most of the
    systemic activities is not due to carbosulfan per se. It is also
    registered for seed treatment and may be applied from the ground or
    air. Treatment may be in furrow, by band, broadcast, side dress, 
    pre-plant, injection or pre-emergence.

         Adequate information on registered or nationally approved 
    pre-harvest intervals, restrictions, etc. was not provided to the
    meeting. Application rates were received too late for consideration in
    this evaluation, but are included in Table 1 which summarizes the
    available information on use patterns for those commodities for which
    residue data were also provided. Information on experimental uses in
    the U.S.A. was also received although these uses do not yet represent
    U.S. good agricultural practice. This information is summarized in
    Table 2 for those commodities for which residue data were also
    available. The information available (Tables 1 and 2 and similar
    information on crops for which there were no residue data) does not
    allow an estimate of MRLs based on nationally approved uses. Other
    information on "suggested" uses was provided, but without safety
    intervals, and it could not be determined whether these uses are
    approved in any country.

        Table 1.  Summary of world-wide registered carbosulfan formulations

                                                                                              

                                                     Application
                                   Formulation       rate kg
                                   (wt/vol for       a.i./ha or
    Commodity      Country         EC and WP)        (g a.i./100L)            Application1
                                                                                              

    Apples         Greece          25% EC            (50-75)                  1
                   Korea           25% WP            1.25                     1
                   Taiwan          48.3 EC           0.1-2.4 (wax apple)
    Brassica       Taiwan          3% G              1.2                      -
                   U.K.            10% G             (50)                     3
    Brassica       U.K.            10% G                                      3
     (leafy)
    Carrots        Taiwan          5% G              3.5                      -
    Citrus         Greece          25% EC            (50-75)                  1
                   Israel          25% EC            1.25                     1
                   Tunisia         25% EC            (50)                     1
                   Taiwan          40 WP             0.8(lemon & orange)
                                   48.3 EC           0.5-1 (orange)
    Corn           France          5% G              0.5                      3
                   Greece          25% EC            0.5-0.6                  1
                   Indonesia       25% ST            0.5-1% a.i./kg seed A
                   Pakistan        20% EC            0.1-0.2                  1
                   Philippines     25% ST            0.2                      A
                   Spain           5%-10% G          0.65-0.75                3
                   Swaziland       25%               2.5-3                    C
                   Taiwan          3 G               1.2
                   Zimbabwe        25% EC            3                        4
    Pears          Greece          25% EC            (50-75)
    Potato         Greece          2.5% EC           0.4-0.5                  1
                   Spain           2% D              0.5                      15
                                   25% EC            0.375-0.5                15
                   Yugoslavia      25% EC                                     1
                                   1.5% D                                     1
    Rice           Bangladesh      20% EC            0.2-0.5                  1
                   India           20% EC            0.2                      1
                   Indonesia       20% EC            0.2-0.4                  1
                                   25% ST            0.5-1%/kg seed           A(upland
                                                                              rice)
                   Korea           25% EC            0.29                     1
                                   1.5% D            0.6                      5
                   Malaysia        20% EC            0.2-0.4                  1
                                   2% D              0.6                      1
                   Philippines     20% EC            0.2-0.25                 1
                                   150 EC            0.2                      1
                                                                                              

    Table 1.  (continued)

                                                                                              

                                                     Application
                                   Formulation       rate kg
                                   (wt/vol for       a.i./ha or
    Commodity      Country         EC and WP)        (g a.i./100L)            Application1
                                                                                              

                   Sri Lanka       2% D              0.5                      1
                                   20% EC            0.2-0.5                  1
                   Taiwan          1% D              0.5-1.2                  C
                                   2% D              0.8-1.2                  6C
                                   40% WP            0.3-0.4                  1
                                   48.3% EC          0.5                      1
                                   30 WP             0.45
                   Thailand        20% EC                                     1
                                   5G                2
    Sorghum        France          5% G              0.5(corn extension) 3
                   Spain           5% G              0.45-0.75                3
                                   10% G             0.45-0.75                3
    Soybean        Indonesia       20% EC            0.2-0.4                  1
                                   25% ST            0.5-1% a.i./kg seed      A

    Sugar beets    France          5% G              0.6                      3
                   Greece          25% EC            0.5                      1
                   Spain           5% G              0.6-0.75                 3
                                   10%G              0.6-0.75                 3
                   U.K.            10% G             3.0 g a.i./100m of row   3
    Swedes         U.K.            10% G                                      3
     (rutabaga)
    Wheat          Greece          25% EC            0.4                      C
                                                                                              

    1  APPLICATION RATES CODE

    1. Foliar:     Ground application
    2. Foliar:     Aerial application
    3. Soil:       In-furrow
    4. Soil:       Band
    5. Soil:       Broadcast
    6. Soil:       Sidedress
    7. Soil:       Pre-plant incorporated
    8. Soil:       Root zone injection
    9. Soil:       Pre-emergence
    A. Seed Treatment
    B. Seed Soak
    C. Other

    Table 2. Experimental uses in the U.S.A.1

                                                                                              

    Commodity         Formulation        Application (rate/restrictions)
                                                                                              

    Alfalfa           4EC2               0.125-1 lb. a.i./A; 1 spray appli./cutting;
                                         3 appli. per season; 9 mo. crop rotation
                                         restrictions, reed/forage restriction; Limited
                                         to certain states.

    Apples            25WP               0.125-0.5 lb a.i./A; per 100 Gal full coverage
                                         (dilute) or 0.5-2 lb. a.i./A for concentrate
                                         sprays.

    Citrus            2.5EC3             5-60 oz. a.i./A (0.35-4.2 kg a.i./ha) full
                                         coverage, 2-4 appli./season, depending on
                                         specific label instructions.

    Field corn        4EC                1 lb. a.i./1300 linear feet (1 acre with 40
                                         inch row space) at plant

                                         or

                                         2 lb. a.i./A broadcast at plant.

                      OR:

                      4EC                0.125-0.5 lb. a.i./100 gal full cover (dilute)
                                         or 0.5-2 lb. a.i./A for concentrates.

    Sorghum           4EC                0.5 lb. a.i./20-40 gal/A to plant base.
                                         (ground only)

                                         or

                                         per Gal/A for aerial 30-day graze and harvest
                                         restrictions. 3 applications/season.
                                                                                              

    1  Uses listed are for experimental purposes and do not represent established good 
       agricultural practices in the U.S.A.
    2  4 lb. a.i./Gal.
    3  2.5 lb. a.i./Gal.
    
    RESIDUES RESULTING FROM SUPERVISED TRIALS

         Over 70 residue studies were submitted from supervised residue
    trials on a variety of crops grown in America, Asia or Europe. The
    data are summarized in Tables 3a-i.

    Root and Tuber Vegetables

         Data were available from three European countries for either
    carrots, potatoes, sugar beets or rutabagas (Table 3a). Application
    rates were generally consistent with the 0.5-2 kg a.i./ha foliar rates
    "suggested" for sugar beets and potatoes, with the exception of the
    French trials. No pre-harvest intervals were suggested. While residues
    in most samples were below 0.05 mg/kg each of carbosulfan, carbofuran
    and 3-hydroxycarbofuran, a significant number exceeded that level.
    Maximum total carbamate residues (sum of the maxima of the three
    residues in any one set of data) were: carrots <0.07 mg/kg, potatoes
    0.22 mg/kg, sugar beet roots 0.71 mg/kg and rutabaga roots 0.95 mg/kg.
    Carbosulfan was generally the predominant root residue from foliar
    spray or in-furrow granular applications except in one rutabaga sample
    where carbofuran was much the highest.

         Harvest-to-analysis intervals and temperatures were not provided
    in many cases. For carrots, storage was for 20 days with
    refrigeration; potatoes unknown conditions (French trials) and
    intervals unknown to 1 year at 20C (U.K.); sugar beets 20 and
    unknown to 9 months (France) and 1 month-1.5 yr., unknown temperature
    (U.K.). In storage trials (see "Storage" under "Fate of Residues")
    residues were constant over 21 months at -18C (0F), but with some
    conversion of carbosulfan to carbofuran.

    Brassica

         Data were available (Table 3b) for head cabbage, Brussels sprouts
    and cauliflower from the U.K., where the 5G formulation used in the
    trials is approved for use, but information was provided too late for
    the meeting to determine whether the application rates reflected
    approved practice. "Suggested" uses (no interval) for vegetables are
    2.5-5kg a.i./ha or EC foliar at 0.25 to 0.5 kg a.i./ha.

         In all cases individual residues of carbosulfan, carbofuran, and
    3-hydroxycarbofuran were <0.05 mg/kg in the portions of the
    commodities to which limits normally apply, giving a total carbamate
    residue below 0.15 mg/kg. Residues of 3-hydroxycarbofuran on whole
    Brussels sprouts plants ranged up to 0.52 mg/kg.

         Samples were stored at 20C for periods ranging from unknown to
    1 year. In storage studies (see "Fate of Residues-In Storage") 40% of
    the total residue was lost within three weeks.


        Table 3a.  Residues of carbosulfan and metabolites in root and tuber vegetables resulting from supervised field trials

                                                                                                                                              

                                              Application                                               Residues, mg/kg
    Crop        Country   Year                                                                                                                
                                           Rate,                      Interval,                                  3-OH-           FMC Reports
                                   No.   kg a.i./ha    Formulation      days        Carbosulfan    Carbofuran    Carbofuran      1984
                                                                                                                                              

    carrots     France    1981     1     1 (furrow)    5G             125           <0.01(1)1      <0.01(1)      <0.05(1)        VII-3

    potatoes    France    1979     1?    1.25          not given      not given     <0.01(5)       <0.06(5)      <0.01(5)        VI-5
                          1980     1?    25-37.5       not given      88-123        <0.01(9)       <0.01(9)      <0.01(9)
                          1981     1?    1.25-50       not given      not given     <0.01(15)      <0.01(11)     <0.05(11)
                          1981     1?    50            not given      not given     0.16(1)

                Italy     1981     1?    30            not given      not given     -              <0.04(5)      <0.05(5)

                U.K.      1978     1     0.75          25EC           79-100        <0.05(8)       <0.05(8)      <0.05(8)        VII-5 &
                                                                                                                                 VI-4

                          1979-    1-2   0.75          25EC           66-68         <0.05(14)      <0.05(14)     <0.05(14)       VII-5 &
                          80                                                                                                     VI-4

                          1980     62    0.75          25EC           14            <0.03(4)       <0.01(4)      <0.01(4)        VII-5 &
                                         (foliar)                                                                                VI-4

                                                                      28            <0.03(4)       <0.01(3)      <0.01(4)
                                                                                                                 0.02(1)
                                                                                                                                              

    Table 3a (2)

                                                                                                                                              

                     Application                                                       Residues, mg/kg
    Crop,                                                                                                                                     
    Country,          Rate                                                                                          3-OH-
    Year         No   kg a.i./ha  formulation   Days              Carbosulfan                Carbofuran           Carbofuran          Ref.
                                                                                                                                
                                                          Roots             Foliage      Roots      Foliage    Roots     Foliage      VII-2

                                                                                                                                              

    Sugar
    beets,
    France,                                     172
    1978         1    0.6-0.75    5G            (mature)  <0.05(4)1         <0.05(4)     <0.05(4)   <0.05(4)   <0.05(4)  <0.05(4)

    1979         1    0.6         5G            129-132   <0.05(10)         <0.05(12)    <0.05(12)  <0.05(12)  <0.05(12) <0.05(12)    VII-2
                      (in furrow)                         0.06 (1)
                                                          0.25 (1)

                 1    1.8         5G            129-132   <0.05-0.1(5)      <0.05(12)    <0.05(12)  <0.05(12)  <0.05(12) <0.05(10)
                      (in furrow)                         [0.13-0.2]7(2)                                                 [0.09-0.1](2)
                                                          [0.3-0.4] (2)

                 1    0.6         5G            159-162   <0.05(11)         <0.05(12)    <0.05(12)  <0.05(12)  <0.05(11) <0.05(12)
                      (in furrow)                         0.06 (1)                                             0.06 (1)

                 1    1.8         5G            159-162   <0.05(11)         <0.05(11)    <0.05(11)  <0.05(11)  <0.05(12) <0.05(8)
                      (in furrow)                         0.06 (1)                                  0.07 (1)             [0.06-0.13](4)
                                                                                                                                              

    Table 3a (3)

                                                                                                                                              

                      Application                                                       Residues, mg/kg
    Crop,                                                                                                                                     
    Country,              Rate                                                                                 3-OH-
    Year         No   kg a.i./ha  formulation   Days      Carbosulfan                    Carbofuran            Carbofuran             Ref.
                                                                                                                                              

    Sugar
    beets,
    U.K.,                                                 seedlings                      seedlings             seedlings
    1981                                                                                                                 
                 1    3.0ga.i./   10G           40        <0.05(1)1                      <0.05(1)              <0105(1)               VIII-
                      100m                                                                                                            8
                                                          Roots             Leaves       Roots      Leaves     Roots     Leaves
                                                                                                                                    
                 1    (in furrow)               104       <0.05(1)          <0.05(1)     <0.05(1)   <0.05(1)   <0.05(1)  <0.05(1)
                 1    (in furrow)               181       <0.05(1)          <0.05(1)     <0.05(1)   <0.05(1)   <0.05(1)  <0.05(1)

    1978         6    0.5(foliar  25EC          14        <0.05(2)          <0.06(1)     <0.05(4)   <0.05(2)   <0.05(4)  <0.24(1)     VII-
                      spray)                              0.08(1)           0.15(1)                 0.06(1)              0.3(1)       4
                                                          0.66(1)           0.21(1)                 0.07(1)              0.8
                                                                            1(1)                                         1.1

                                                28        <0.05-0.09(4)     <0.05-       <0.05(4)   <0.05-     <0.05(4)  <0.3(2)
                                                                            0.11(3)                 0.07(4)              [0.5-0.6]7 (2)
                                                                            0.47(1)

                 1-2  0.5         25EC          68-118    <0.05(9)          <0.05(9)     <0.05(9)   <0.05(9)   <0.05(9)  <0.05(5)
                      (broadcast                (mature)                                                                 [0.08-0.13](4)
                      foliar
                      spray)

    Swedes
    (rutabaga),
    U.K., 1981   1    1-1.2       10G           121-123   <0.05(3)          <0.05(3)     <0.05(2)   <0.05(1)   <0.05(3)  <0.05(3)
                      (in furrow)               (mature)                                 0.85(1)    [0.4-
                                                                                                    0.6] (2)
                                                                                                                                              

    Table 3b. Residues of carbosulfan and metabolites in brassica and legume vegetables resulting from supervised field trials

                                                                                                                                

                               Application                                                   Residues, mg/kg
    Crop,                                                                                                                         
    Country,                    Rate,                     Interval,                                      3-OH-
    Year                No.   kg a.i./ha    Formulation   days           Carbosulfan     Carbofuran    Carbofuran      Ref.
                                                                                                                                

    Cabbage (head),
    U.K.,
    1979                1     2-3           5G            105-152        <0.05(10)1      <0.05(10)     <0.05(10)       VI-6&
                              (furrow at                                                                               VII-1
                              seedling)

    Brussels sprouts,
    U.K.,
    1978                1     2 (furrow     5G            131-146        <0.05(4)        <0.05(4)      <0.05(4)        "
                              at transpl.)

    whole plant         1     3.1 (furrow   5G            120            0.05(2)         0.05(2)       0.05-0.52(6)    "
                              at seedling)                                                             (0.4 av.)

    cauliflower,
    U.K.,
    1979                1     2-3 (furrow   5G            105-152        <0.05(20)       <0.05(20)     <0.05(20)       "
                              (at seeding                 (curds)
                              or transplt.)

    Legume Vegetables

    Dry beans,
    Brazil,
    1983                1     0.75-1        25EC          87             <0.02(1)        <0.02(1)      <0.02(1)        V-6
                              kg a.i./100
                              kg seed
                              treatment
                                                                                                                                    

    Table 3c.  Residues of carbosulfan and/or metabolites in citrus resulting from supervised residue trials

                                                                                                                                              

                     Application*                                                      Residues, mg/kg
                                                                                                                                            
    Country,                                                                        3-Hydroxy-         3-Keto-
    Year,               Rate,        Interval,   Carbosulfan      Carbofuran        carbofuran         carbofuran         Total
    Crop,         No.   kg a.i./ha   Days        Max     Ave      Max      Ave      Max       Ave      Max     Ave     Max     Ave     Ref.
                                                                                                                                              

    U.S.A.        1     0.94            0         .09     .08      .06     (.04)    (.01)       ND**   (.01)8    ND     .15     .13    I-17,
    (FL)                (3 trials)      7        (.01)   (.01)     .05     (.04)    (.03)     (.02)    (.01)   (.01)   (.09)   (.08)   19
    1979                               14          ND      ND      .05     (.04)    (.02)     (.01)    (.02)   (.01)   (.08)   (.06)
                                       28          ND      ND     (.03)    (.03)    (.01)     (.01)    (.01)     ND    (.04)   (.04)

    oranges       5     0.94-3.8        0         .16     .12      .28      .23     .41        .28      .09     .07     .90     .71
                        (10 total)      7        (.03)   (.03)     .26      .19     .39        .24      .12     .05     .74     .50
                        (3 trials)     14        (.01)     ND      .28      .20     .31        .23      .10     .07     .68     .53
                                       28          ND      ND      .28      .21     .41        .28      .10     .07     .70     .56

                  4     0.94-3.8        0         .14     .12      .16      .16     .37        .34     (.02)   (.02)    .68     .64
                        (9.4 total)     7        (.02)   (.02)     .17      .14     .41        .38     (.04)   (.04)    .59     .58
                        (1 trial)      14        (.01)   (.01)     .15      .14     .31        .31     (.04)   (.04)    .50     .49
                                       28        (.01)   (.01)     .17      .15     .34        .32     (.04)   (.04)    .55     .52

    grapefruit    4     0.94-3.8        0        (.04)   (.04)     .24     .22      .35        .34      .06     .05     .67     .65
                        (9.4 total)     7        (.01)   (.01)     .20     .18      .24        .23      .05    (.04)    .49     .46
                        (1 trial)      14          ND      ND      .26     .20      .28        .26      .09     .08     .62     .56
                                       28          ND      ND      .17     .16      .23        .22      .05    (.04)    .43     .42
                                                                                                                                              

    Table 3c. (continued)

                                                                                                                                              

                    Application*                                               Residues, mg/kg
    Country,                                                                                                                            
    Year,              Rate,             Interval,                   3-keto-        3-OH-
    Crop         No.   kg a.i./ha        Days       7-phenol         7-phenol       7-phenol        Total4     Dibutylamine 5,6,7
                                                                                                                                              

    oranges                                 0       0.02             0.04           0.07            0.13       0.29                  I-1,8
                                                    [0.005-0.07)7    [0.03-0.04]    [0.06-0.08]                [0.19-0.41]

                 5     (3 trials)
                       Note: same           7       0.03             0.03           0.06            0.12       0.25
                       trials as                                                                               [0.14-0.36]
                       oranges             14       0.02             0.03           0.07            0.12       0.20
                       above where          5                                                                  [0.14-0.32]
                       applications        28       <0.005           0.04           0.06            0.10       0.21
                       and 3 trials                 (detection                                                 [0.15-0.29]
                       were conducted               limit)
                                                                                                                                              

    * All 2.5EC formulation
    ** ND = none detected = <0.01 mg/kg for individual carbamates.

    Table 3c (2)

                                                                                                                                              

                 Application*                                                   Residues, mg/kg
                                                                                                                                              
    Country,                                                                           3-Hydroxy-       3-Keto-
    Year,              Rate,     Interval,  No. of     Carbosulfan     Carbofuran      carbofuran       carbofuran         Total9
    Crop,       No.  kg a.i./ha    Days     Samples    Max    Ave      Max    Ave      Max     Ave      Max     Ave     Max     Ave     Ref.
                                                                                                                                              

    U.S.A.
    (FL,TX),
    1980-81,
    Oranges     5    4.6 (2x)       7       6           0.06  0.02     0.63   0.53     0.58    0.47     0.20    0.18    1.37    1.19    I-3,
    (Valenica)       1 (3x)                                                                                                             4,20
                     (3 trials)

    oranges     4    4.6 (2x)       0       2           0.33   0.30    0.26   0.22     0.46    0.45     0.06    0.06    1.05    1.04
    (Hamlin &        1 (2x)         7       4           0.05   0.05    0.24   0.21     0.65    0.50     0.08    0.07    1.00    0.83
    Marrs)           (2 trials)    14       2          (0.04) (0.03)   0.20   0.20     0.42    0.40     0.10    0.09    0.76    0.71
                                   28       2          (0.02) (0.02)   0.26   0.25     0.34    0.32     0.10    0.10    0.72    0.70

    grapefruit  4    4.6 (2x)       0       2           0.14   0.14    0.63   0.60     0.46    0.42     0.10    0.10    1.33    1.25
                     1 (2x)         7       6           0.09  (0.04)   0.69   0.40     0.53    0.36     0.25    0.13    1.56    0.93
                     (3 trials)    14       2           0.10   0.07    0.74   0.70     0.50    0.48     0.24    0.24    1.54    1.49
                                   28       2          (0.02) (0.02)   0.62   0.58     0.46    0.46     0.27    0.26    1.36    1.32
                                                                                                                                              

                                                   3-keto-            3-Hydroxy-     Total                            No. of
                                 7-phenol          7-phenol           7-phenol       phenolics      DBA               Samples      Ref.
                                                                                                                                              

    oranges     5    as above    [(0.04)-0.13)]7   [(0.04)-0.09)]     [0.08-0.23]    [0.16-0.45]    [0.43-0.64]       16           see
                                 0.070.02         0.060.01          0.130.05      0.26+0.09      0.43                           above

    as above    4    as above    [(0.04)-0.15]     [(0.02)-0.09]      [(0.04)-0.24]  [0.10-0.55]    [0.18-0.66]       12
                                 0.090.03         0.05O.02          0.150.09      0.290.10      0.45
                                                                                                                                              

    * All 2.5EC formulation

    Table 3c (3)

                                                                                                                                            

                Application*                                                 Residues, mg/kg                              Ref. 1-22
                                                                                                                          Total
    Country,                                                                            3-OH-           3-Keto-           carbamate
    year,            Rate         Interval,  No. of    Carbosulfan      Carbofuran      carbofuran      carbofuran        metabolites
    crop        No.  kg a.i./ha   Days       Samples   Max     Ave      Max    Ave      Max     Ave     Max      Ave      Max*    Ave
                                                                                                                                            

    USA
    (CA),
    1982,
    oranges
    (Valencia)  2    1.7 (aerial)    0          4       0.08   (0.04)    0.08  (0.04)   (0.02)  (0.02)  (0.01)   (<0.01)   0.11    0.06
                     2.5EC

                                     7          4      (0.01)  <0.01     0.05  (0.04)   (0.02)  (0.02)  (0.01)   (0.01)    0.08   (0.06)

                                    14          4      (0.01)  <0.01    (0.04) (0.03)   (0.03)  (0.02)  (0.01)   (0.01)   (0.08)  (0.06)

                                    28          4      <0.01   <0.01    (0.01) <0.01    (0.02)  (0.01)  (<0.01)  (<0.01)  (0.03)  (0.02)

    * Total metabolite max. based on max. for any individual sample

    CONT'D
                                                       Phenolic residues (18 samples)           DBA                       Ref.
                                                                                                                                           
                                                                                                                          I-13,
                                     0          4      All phenolics <0.01 mg/kg at             (0.11)                    15
                                                                                                [0.01-0.11]7
                                     7          4      all intervals except one                 (0.17)
                                                                                                [0.11-0.2]
                                    14          4      0.03 mg/kg estimated residue             (0.13)
                                                                                                [<0.1-(0.15)]
                                    28          4      at 0 day                                 (0.14)
                                                                                                [0.11-0.18]
                                                                                                                                            

    Table 3c (4)

                                                                                                                                              

                  Application**                                               Residues, mg/kg                             Ref. 1-21
                                                                                                                                       
    Country,                                                                            3-Hydroxy-      3-Keto-
    year,              Rate       Interval,  No. of    Carbosulfan      Carbofuran      carbofuran      carbofuran           Total
    crop        No.  kg a.i./ha   Days       Samples   Max     Ave      Max    Ave      Max     Ave     Max      Ave      Max     Ave
                                                                                                                                              

    USA         2      1.7           0          8      1.7      0.53    0.39   0.23     0.83     0.16    0.06    (0.03)   2.3     0.94
    (CA,AZ) ,                        7          4      0.87     0.27    0.86   0.42     0.36     0.12    0.19     0.08    2.2     0.89
    1982,                           14          8      0.35     0.15    0.77   0.47     0.36     0.14    0.18     0.08    1.7     0.83
    oranges                         28          8      0.11    (0.04)   0.31   0.26     0.22     0.08    0.08     0.05    0.55    0.43

                4      1.7           0          8      0.95     0.58    0.58   0.28     0.08    (0.04)  (0.04)   (0.01)   1.5     0.91
                                     7          8      0.41     0.27    0.90   0.38     0.19     0.07    0.14     0.05    1.5     0.76
                                    14          8      0.27     0.14    0.70   0.40     0.15     0.07    0.09     0.05    1.0     0.65
                                    28          8      0.10    (0.03)   0.51   0.29     0.09     0.05    0.06    (0.03)   0.66    0.33
                                                                                                                                              

    * Total max. based on max. total in any one sample
    ** All 2.5EC formulation

    Table 3c (4) (continued)

                                                                                                                                              

                                                                   Phenolic and DBA residues
                                                                                                                       
                     Rate
                   kg a.i./                                                         3-Hydroxy-
    Cont'd           ha     Days  Samples  7-Phenol              3-Keto-7-phenol    7-phenol           Phenolics          DBA           Ref.
                                                                                                                        
                                           Range         Ave.    Range      Ave.    Range      Ave.    Range        Ave.
                                                                                                                                              
                                                                 3
                            0     8        (0.01)2 0.09  (0.04)  ND (0.02)  (0.01)  ND-(0.02)  (0.004) (0.02)-0.12  0.09  all studies
                                                                                                                          0.38  0.24   I-
                2    1.7    7     24       ND 0.17       0.05    ND- 0.06   (0.02)  ND- 0.06   (0.02)  (0.02)-0.25  0.09                6,7

                            14    8        (0.02)-0.10   0.05    ND- 0.06   (0.02)  ND- 0.06   (0.02)  (0.02)-0.22  0.09  [0.08-1.8]7

                            28    8        (0.01)-(0.04) (0.03)  ND-(0.04)  (0.02)  ND-(0.04)  (0.01)  (0.01)-0.11  0.09

                            0     8        (0.03)-0.10   0.07    ND (0.02)  (0.01)  ND-(0.03)  (0.01)  0.05-0.11    0.08

                            7     24       ND-0.11       0.05    ND-0.05    (0.02)  ND-(0.03)  (0.01)  ND-0.19      0.08

                4    1.7    14    8        ND-0.12       0.06    ND-(0.04)  (0.02)  ND-(0.02)  (0.01)  ND-0.19      0.09

                            28    8        ND-0.07       (0.03)  ND-(0.043) (0.02)  ND-(0.03)  (0.01)  ND-0.12      0.06
                                                                                                                                              

    Table 3c (5)

                                                                                                                                 

                       Application                                                  Residues, mg/kg
    Country,                                                                                                                     
    year,                                   Interval,                      3-keto-       3-OH-
    crop             No.    kg a.i./ha      days          7-phenol         7-phenol      7-phenol      DBA             Ref.
                                                                                                                                 

    USA (CA,AZ),
    1982,            2      1.7              0            [<0-01-0.09]7    <0.01         <0.01         0.42            I-12,
    grapefruit              2.5EC                                                                                      16
                            formulation     7-8           [(0.03)-0.05]    at all        at all        0.2-0.4
                                                                           intervals     intervals
                                            14            (0.02)                                       0.16

                                            28            [0.01-0.03]                                  0.28
                                                                                                                                 

    Table 3c (6)

                                                                                                                                       

                Application                                                 Residues, mg/kg                               Ref. 1-24
                                                                                                                          Total
    Country,                                                                            3-Hydroxy-      3-Keto-           carbamate
    year,            Rate         Interval,  No. of    Carbosulfan      Carbofuran      carbofuran      carbofuran        metabolites
    crop        No.  kg a.i./ha   Days       Samples   Max     Ave      Max    Ave      Max     Ave     Max      Ave      Max     Ave
                                                                                                                                       

    USA (FL),   4    l(2x)           0       4          0.09   0.06     0.36   0.30     0.57    0.44    (0.04)   (0.03)   0.95    0.76
    1982,            4.2(2x)         7       4         (0.01)  ND       0.40   0.26     0.49    0.37    (0.04)   (0.03)   0.93    0.66
                     2.5EC          14       4           ND    ND       0.25   0.22     0.50    0.39    (0.03)   (0.03)   0.74    0.64
                     formulation    28       4           ND    ND       0.19   0.18     0.42    0.36    (0.03)   (0.03)   0.64    0.57
                                                                                                                                       

    ND = none detected = <0.01 mg/kg

                                                                                                                                       

                                                                              Phenolic and DBA residues
                                                                                                                                       
                                                                         3-kote        3-OH            Total
                                                       7-phenol          7-phenol      7-phenol        phenolics    DBA (Max)     Ref.
                                                                                                                                       

                     Cont'd       0         4          (0.04)            (<0.01) to    0.06            0.11         0.43-0.49     I-11,
                                                       [(0.03)-0.05]7    (0.02)        [0.05-0.07]                                14
                                  7         4          0.03              at all        0.09            0.13         0.41-0.48
                                                       [(0.01-0.05]      intervals     [0.05-0.12]
                                  14        4          (0.02)                          0.07            0.1          0.32-0.36
                                                       [0.02-0.03]                     [0.05-0.08]
                                  28        4          (0.02)                          0.06            0.09         0.29-0.40
                                                       [(0.02)]                        [0.05-0.07]
                                                                                                                                       

    Table 3c (7)

                                                                                                                                       

                   Application                                     Residues, mg/kg10
    Country,                                                                                                                           
    year,               Rate,                         Interval,                                              3-Hydroxy-
    crop           No.  kg a.i./ha                    Days         Carbosulfan           Carbofuran          carbofuran        Ref.
                                                                                                                                       

                                                                   Fruit      Peel       Fruit     Peel      Fruit     Peel
    Italy,         2    75g/hl                           0          0.67       3.9        0.48      1.1      <0.05     0.15    VI-3
    1982,               25EC                             0          0.71       3.5        0.47      1.7     +<0.05     0.13
    oranges             formulation     untreated        0         <0.05      <0.05      <0.05     <0.05     <0.05    <0.05    VIII-5
                                                        14          0.96       3.4        1.07      1.9       0.07     0.31
                                                        14          0.66       1.8        0.90      1.2       0.05     0.17
                                        untreated       14         <0.05      <0.05      <0.05     <0.05     <0.05    <0.05
                                                        28          0.46       1.3        1.51      2.3       0.15     0.19
                                                        28          0.27       1.1        0.75      1.6       0.08     0.12
                                        untreated       28         <0.05      <0.05      <0.05     <0.05     <0.05    <0.05
                                                        42          0.30       1.2        1.09      2.6       0.06     0.36
                                                        42          0.28       0.71       0.95      1.8     +<0.05     0.23
                                        untreated       42         <0.05      <0.05      <0.05     <0.05     <0.05    <0.05
                                                        56          0.7        2.9        0.08      0.3
                                                        56          0.25       0.4        0.67      2.2     +<0.05    <0.05
                                        untreated       56         <0.05      <0.05      <0.05     <0.05     <0.05    <0.05
                                                                                                                                       

    Table 3d.  Residues of carbosulfan and metabolites in pome fruit resulting from supervised field trials

                                                                                                                                                

                      Application                                                                 Residues, mg/kg
                                                                                                                                                
    country,                                                                                                              Total
    year,        Rate,                     Interval   No. of                                  3-Keto-      3-Hydroxy-     carbamate
    crop         kg a.i./ha  formulation   Days       Samples   Carbosulfan    Carbofuran     carbofuran   carbofuran     metabolites**   Ref.
                                                                                                                                                

    USA (16      2.2           4EC            0          8      0.12 - 0.71    0.12 - 0.32       ND*       0.04 - 0.34    0.17 - 0.55     III-1,
    trials, 8    (delayed      +                                Average=0.52   Average=0.21                Average=0.18   Averaqe=0.39    2,6
    states),     dormant       4EC
    1981,        (1X) +                      14          8      0.07 - 0.96    0.04 - 0.29       ND        0.04 - 0.31    0.08 - 0.55
    apples       1.1                                            Average=0.36   Average=0.16                Average=0.16   Average=0.31
                 foliar
                 (3X)                        28         24      0.05 - 0.96    0.03 - 0.38       ND        ND - 0.33      0.33 - 0.68
                                                                Average=0.32   Average=0.16                Average=0.12   Average=0.28

                 2.2           4EC            0          4      0.26 - 0.56    0.25 - 0.35       ND        ND - 0.05      0.27 - 0.40
                 (delayed                                       Average=0.40   Average=0.29                Average=0.03   Average=0.32
                 dormant       +
                 1X) +                       14          4      0.11 - 0.45    0.05 - 0.14       ND        ND - 0.05      0.05 - 0.19
                 1.1           25WP                             Average=0.26   Average=0.10                Average=0.03   Average=0.13
                 foliar
                 (3X)                     27-28          8      0.06 - 1.60    0.04 - 0.72       ND        0.02 - 0.23    0.08 - 0.95
                                                                Average=0.50   Average=0.29                Average=0.11   Average=0.40
                                                                                                                                                

    *ND = <0.02 mg/kg          **Total carbamate max. is max. for any one sample

    Table 3d. (continued)

                                                                                                                                                

                               CONTINUED                 Phenolic residues                               Dibutylamine residues
                                                                                                                                                
                             No. of
                   EC + EC   Samples   Days   Range or average, corrected, mg/kg
                                                                                                   
                                              7-Phenol     3-Keto-     3-Hydroxy-                  No. of              Average
                                                           7-phenol    7-phenol     Total          Samples    Days     [range], mg/kg
                                                                                                                                                

                                                                                                      8         0      0.23
                                                                                                                       [0.15-0.27]
                   Range               0-     ND*-0.15     ND-0.05     ND-0.08      ND-0.24          10        14      0.22
                   Average   44        28     0.06         0.01        0.02         0.09                               [0.09-0.37]
                                                                                                     26        28      0.2
                                                                                                                       [<0.1-0.52]
                   EC + WP
                   Range     18        0-     0.02-0.17    ND-0.03     ND-0.06      ND-0.06
                   Average             28     0.06         0.01        0.02         0.02
                                                                                                                                                

    ND = <0.01

    Table 3d (2)

                                                                                                                            

                       Application                                      Residues, mg/kg
                                                                                                               
    Country,                                          Carbosulfan         Carbofuran          3-OH-carbofuran
    year,                    Rate,                        Site                Site                Site
    crop           No.       kg a.i./ha     Days      1         2         1         2         1         2         Ref.
                                                                                                                            

    Italy,         2         75 ga.i/hl     0         2.1       0.8       0.5       0.1       0.08      0.1       VIII-2
    1981,          (site 1)  25EC                     2.5       1.7       0.5       0.2       0.3       0.1
    apples         3         fomulation
                   (site 2)  (aerial)       14        1.2       1         0.2       0.2       0.1       0.2
                                                      1.9       0.7       1.2       0.1       0.4       0.1

                                            21        1.4       0.7       0.8       0.2       0.3       0.2
                                                      1.4       0.7       0.3       0.2       0.07      0.1

                                            28        0.3       0.8       0.6       0.2       0.1       0.2
                                                      1         0.8       0.6       0.3       0.3       0.2

                                            35        0.7       0.2       0.9       0.2       0.4       0.2
                                                      1.2       0.8       0.3       0.2       0.2       0.1

                                            42        1         0.2       0.6       0.1       0.4       0.1
                                                      0.1       0.2       0.9       0.2       0.3       0.3
                                                                                                                            

    Table 3d (3)

                                                                                                                                  

                                                                           Residues, mg/kg
                                                                                                                      
                   Application                        Carbosulfan            Carbofuran           3-Hydroxycarbofuran
    country,                                                                                                          
    year,               Rate,          Interval    Site        Site        Site        Site         Site       Site
    crop           No.  kg a.i./ha     Days      1     2     3     4     1     2     3     4      1     2     3     4       Ref.
                                                                                                                                  

    UK,            4-5  0.1            7                     1     1.4               0.2   0.5                0.1   0.3     VIII-1
    1980,               (foliar
    apples (Cox,        spray to       10        2.3   0.7               0.6   0.5                0.3   0.3
    Bramley,            run-off)                 2.1   0.7               0.6   0.2                0.3   0.2
    George Cave)        25EC
                        formulation    13-       0.9   0.7   0.6   1.5   0.3   0.5   0.2   0.5    0.2   0.3   0.09  0.08
                                       14        1.5   0.6               0.7   0.3                0.2   0.2
                                                 1.4   1                 0.7   0.6                0.4   0.5
                                                 0.3   0.8               0.8   0.6                0.2   0.5

                                       21                    0.4   0.6               0.2   0.4                0.08  0.2

                                       28        1     1.1   0.6   0.3   1.1   0.5   0.3   0.3    0.8   0.6   0.1   0.2
                                                 0.8   0.6               0.8   0.4                0.7   0.5

                                       35                    0.2   0.4               0.2   0.3                0.2   0.2

                                       42        0.91  0.6               0.8   0.5                0.5   0.4
                                                 0.7   0.2               0.5   0.3                0.3   0.3
                                                                                                                                  

    Table 3d (4)

                                                                                                                                                
                                                                                           Residues, mg/kg
                       Application                                                                                                    
    Country,                                                                                                           Total
    year,       Rate,                    Interval  No. of                                  3-Keto-      3-Hydroxy-     carbamate
    crop        kg a.i./ha  formulation  Days      Samples   Carbosulfan    Carbofuran     carbofuran   carbofuran     metabolites**    Ref.
                                                                                                                                                

    USA (6      2.2           4EC          0                 0.18 - 1.07    0.04 - 0.11       ND*       ND - 0.06      0.06 - 0.16      III-11
    trials,     delayed                                      Average=0.58   Average=0.06                Average=0.04   Average=0.11
    4 states),  dormant       +
    1981-82,    1X + 1.1                  14                 ND - 0.08      ND - 0.04         ND        0.05 - 0.09    0.05 - 0.10
    pears       foliar 2X     4EC                            Average=0.05   Average=0.03                Average=0.06   Average=0.09

                                          28                 ND - 0.23      ND - 0.03         ND        0.02 - 0.08    0.02 - 0.09
                                                             Average=0.08   Average=ND                  Average=0.05   Average=0-06

                2.2           4EC          0                 0.38 - 0.92    0.04 - 0.08       ND        ND - 0.04      0.04 - 0.12
                delayed                                      Average=0.67   Average=0.07                Average=0.02   Average=0.08
                dormant       +
                1X + 1.1                  14                 0.12 - 0.19    0.02 - 0.05       ND        0.03 - 0.06    0.05 - 0.11
                foliar 2X     25WP                           Average=0.15   Average=0.03                Averaqe=0.04   Average=0.08

                                          28                 0.05 - 0.17    ND-0.03           ND        0.02 - 0.05    0.02 - 0.08
                                                             Average=0.09   Averace=0.02                Average=0.03   Average=0.05
                                                                                                                                                
                                                                            3-Keto            3-Hydroxy Total                           Ref.
                                                             7-Phenol       7-phenol          7-phenol  Phenols        Dibutylamine     III
                                                                                                                                                
                              EC+EC
    as above    as above      Range        0       36        ND*-0.10       ND - ND           ND - 0.03 ND - 0.11      0.11 - 0.36      10
                              Avg.        28                 0.02           ND                0.01      0.03           0.22             12,
                                                                                                                                        13

                as above      EC+WP
                              Range        0       36        ND - 0.11      ND - ND           ND - 0.01 ND - 0.01      0.04 - 0.2
                              Avg.        28                 0.04           ND                ND        0.04           0.11
                                                                                                                                                

    Table 3e  Residues of carbosulfan and its metabolites in cereal grains, forage and fodder resulting from
              supervised field trials

                                                                                                                            

                         Application                                               Residues, mg/kg
    Country,                                                                                                  
    year,                    Rate,          Interval,   No. of                                     3-Hydroxy-
    crop              No.    kg a.i./ha     Days        Samples      Carbosulfan    Carbofuran     carbofuran       Ref.
                                                                                                                            

    France,           1      0.5 - 1.5      89-193      16           <0.05          <0.05          <0.05            VII-3
    1978-79,                 5G
    grain (mature)           formulation

    plant (whole)                           90-120      32           <0.05          <0.05 - 0.1*   <0.05 - 0.12*
                                                                                                                            

    * Only value >0.05 mg/kg 90 days post-treatment.

    Table 3e (2)

                                                                                                                                                
                     Application                                                    Residues, mg/kg
    Country,                                                                                                                     
    year,               Rate,        Interval,  No. of                                   3-OH-          3-Keto-        Total
    crop           No.  kg a.i./ha   Days       Samples    Carbosulfan    Carbofuran     carbofuran     carbofuran     carbamates     Ref.
                                                                                                                                                

    USA,           1    3.4 (in-
    1981,               furrow
    field corn          at-plant)
    grain               4 EC         114-170    11         <0.01          <0.02          <0.02          <0.02          <0.07          V-5
                        formulation
    fodder                           114-170    11         <0.01          <0.02          <0.01          <0.05          <0.18
                                                                                         [<0.02-0.75]   [<0.02-0.25]   [<0.02-1.03]

    silage                           86-131     11         <0.01          <0.2           <0.2           <0.02          <0.02
                                                                          [<0.02-0.03]   [<0.02-1.6]                   [<0.02-1.6]
                                                                                                                                                

                                                                               phenolic residues
                                                                                                                           DBA
                                                                                    3-Keto       3-Hydroxy
                                                           Crop Part   7-Phenol     7-Phenol     7-Phenol     Total                     Ref.
                                                                                                                                                

    as above       1    as above     86-131     11         Silage
                                                           Range       <0.01-0.56   <0.01-1.30   <0.01-1.69   <0.01-3.55   <0.01-0.03   V-
                                                           Average      0.050.2    <0.110.03    0.140.4                  0.2         2,
                                                                                                                                        3,
                                     114-170    11         Grain                                                                        4
                                                           Range       <0.01        <0.01        <0.01        <0.01        <0.01
                                                           Average     <0.01        <0.01        <0.01        <0.01        <0.01
                                                                                                                                        3,
                                     114-170    11         Stover
                                                           Range       <0.01-0.26   <0.01-0.57   <0.01-1.03   <0.01-1.66   <0.01-0.11
                                                           Average      0.030.06    0.090.2     0.16+0.3     0.280.5    <0.02        3,

                                                                                                                                                
    * Average of duplicate determinations

    Table 3e (3)

                                                                                                                      

                   Application                                             Residues, mg/kg
                                                                                                                      
    Country,
    year,              Rate,         Interval,   No. of                                  3-OH-
    crop        No.    kg a.i./ha    Days        Samples   Carbosulfan    Carbofuran     carbofuran     Ref.
                                                                                                                      

    Brazil,     1      0.23-0.30     101         4         <0.02          <0.02          <0.02          III-21
    1982,              kg a.i./ha
    rice grain         (0.75-1 kg
                       a.i./100 kg
                       seed)
                       25 STD
                       formulation

    Greece,                                                Analytical results available, but no sample history provided
    1983,                                                                                               V-1
    grain

    Brazil,     1      625-875g      115         3         <0.02          <0.02          <0.02          III a-32
    1983,              a.i./100 kg               (in
    wheat              seed=0.75-                dupl.)
                       1 kg a.i./ha
                       25 STD
                       formulation
                                                                                                                      

    Table 3e (4)

                                                                                                                                             

                       Application                                               Residues, mg/kg
    Country,                                                                                                                                 
    year,                  Rate,          Interval,   No. of                                     3-OH-           Total
    crop             No.   kg a.i./ha     Days        Samples     Carbosulfan    Carbofuran      carbofuran      carbamates      Ref.
                                                                                                                                             

    USA (10 trials,  4     1X 2.2         30-39                                                                                  III-15
    7 states),             10G at plant
    1981,                  + 3X 0.56
    sorghum                foliar 4EC

    stalk                                             10*         [<0.1-1.13]    [<0.1-0.-65]    [(0.05)-0.85]   [0.12-2.27]
                                                                  0.25 Av.       0.16 Av.        0.43 Av.        0.84 Av.
                                                                  0.29          0.18           0.27           0.52

    grain                                             10*         [<0.02-0.14]   [<0.02-0.29]    [(0.02)-0.35]   [(0.02)-0.56]
                                                                  (0.04) Av.     0.05 Av.        0.10 Av.        0.19 Av.
                                                                  0.05          0.06           0.09           0.17
                                                                                                                                             

                                                                                                               
                                                                             Phenolic residues
                                                                                                               
                                                                           3-Keto-      3-Hydroxy-
                                                              7-Phenol     7-phenol     7-phenol     Total       DBA
                                                                                                                             

    stalk                                             10*     [0.02-2.5]   [0.14-0.74]  [0.08-0.84]  [0.42-4.1]  [0.16-1.8]     III-14
                                                              1.00.6      0.440.2     0.340.2     1.81.0     0.80.49       16,17

    grain                                             10*     [0.08-0.61]  [0.06-0.46]  [0.02-0.48]  [0.24-1.6]  [0.19-1.1]
                                                              0.190.1     0.140.1     0.160.1     0.490.3    0.480.28
                                                                                                                                             

    * In duplicate

    Table 3f.  Residues of carbosulfan in grass and clover resulting from supervised residues trials

                                                                                                                                                

                       Application                                                        Residues, mg/kg
    Country,                                                                                                                                    
    year,         Rate,        Interval,  No. of                                       3-Keto-            3-Hydroxy-       Total
    crop          kg a.i./ha   Days       Samples  Carbosulfan       Carbofuran        carbofuran         carbofuran       carbamates       Ref.
                                                                                                                                                

    USA (32       Ground or
    trials),      aerial
    1980-81,      spray
    grass &
    clover

    green grass   0.28          7          6       0.46[0.07-1.1]    0.67[<0.03-1.8]   0.04[<0.03-0.11]   10.6010.08-1.2]  1.3[0.04-4.4]   III-
                  0.56         14         10       0.55[0.04-1.5]    0.37[<0.03-2.1]   0.03[<0.03-0.20]   1.7[<0.03-2.4]   1.1[0.04-4.4]   A
                                                                                                                                           29
    green clover  0.28          7          7       0.39[0.04-1.2]    0.47[0.09-1.8]    0.13[<0.03-0.44]   0.87[0.41-1.4]   1.5[0.71-3.4]
                  0.56         14         10       0.22[<0.02-0.54]  0.44[0.04-1.8]    0.6[<0.03-0.34]    1.2[<0.03-4.1]   1.7[0.08-5.1]

    grass hay     0.28          7          6       1.1[0.16-2.4]     1.2[0.24-6.0]     0.07[<0.05-0.25]   1.2[0.26-2.0]    3.0[0.50-8.2]
                  0.56         14         10       0.77[<0.05-3.9]   1.7[<0.05-12.2]   0.05[<0.05-0.35]   [1.6[<0.1-7.2]   3.6[ND-19.8]

    clover hay    0.28          7          7       0.46[0.08-1.1]    1.5[0.10-3.5]     0.23[<0.05-1.1]    2.0[<0.1-5.1]    3.7[0.10-8.8]
                  0.56         14         11       0.31[0.06-0.71]   1.1[<0.05-3.6]    0.19[<0.05-1.0]    6.3[0.22-14.6]   7.7[0.30-17.1]
                                                                                                                                                

    Table 3f. (continued)

                                                                                                                                                
                                                                         Phenolic residues
                                                                                                                                          Total
                                                                     3-Keto            3-Hydroxy-         phenolic
                                                   7-Phenol          7-phenol          7-phenol           metabolites      DBA
                                                                                                                                                

    green grass   0.28          7                  0.40 [ND**-1.51]  0.15[ND-0.36]     0.45[ND-1.64]      1.00[0.07-2.41]  1.6[0.6-3.8]    III-
                  0.56         14                  0.41 [ND-2.69]    0.16[ND-0.47]     0.35[ND-1.66]      0.91[0.04-4.82]  1.1[0.01-2.4]   A
                                                                                                                                           22,
    green clover  0.28          7                  0.28[0.09-0.60]   0.26[0.08-0.45]   0.06[ND-0.16]      0.60[0.18-1.03]  1.7[0.6-3.4]    25,
                  0.56         14                  0.38[0.07-0.99]   0.44[0.12-0.96]   0.12[ND-0.31]      0.94[0.25-2.12]  2.0[0.6-4.9]    26

    grass hay     0.28          7                  0.86[0.12-1.78]   0.34[0.09-1.18]   1.20[ND-5.88]      2.39[0.61-8.06]  2.9[0.2-4.7]
                  0.56         14                  0.70 [ND-3.36]    0.32[ND-1.31]     0.64[ND-2.89]      1.67[0.04-6.70]  1.7[<0.01-3.6]

    clover hay    0.28          7                  1.08[0.06-2.62]   0.94[0.11-2.17]   0.45[ND-0.89]      2.47[0.30-5.43]  5.3[<0.01-12.7]
                  0.56         14                  1.38[0.06-3.86]   1.56[ND-03.60]    1.177[ND-1.95]     3.67[0.08-8.97]  7.3[<0.05-21]
                                                                                                                                                

    * All single applications of 4EC formulation
    ** ND = not detectable = <0.01 mg/kg green; <0.02 mg/kg hay.

    Table 3f (2)

                                                                                                                                          

                                                                                     Residues, mg/kg                      Ref. III-A
                                                                                                                                  30
                                                                                                         Total
    Country,       Application                                                                           cholinesterase
    year,          rate,       Interval,                               3-Keto-           3-Hydroxy-      inhibiting       No.of
    crop           kg a.i./ha  Days      Carbosulfan     Carbofuran    carbofuran        carbofuran      metabolites***   Samples
                                                                                                                                          

    USA (9 states  0.84
    15 trials),    (ground
    green grass    or air)     21        0.28[ND**-1.0]  0.25[ND-1.2]  0.50 [0.06-0.92]  0.04 [ND-0.13]  0.78 [0.06-1.9]  7

    green clover               21        0.29[ND-1.9]    0.34[ND-2.4]  1.2 [ND-2.9]      0.05 [ND-0.17]  1.6 [ND-4.7]     9

    grass hay                  21        0.43[ND-2.0]    0.38[ND-1.3]  0.94 [0.14-1.9]   0.05 [ND-0.23]  1.4 [0.14-3.4]   7

    clover hay                 21        0.43[ND-3.2]    0.57[ND-3.5]  2.8 [0.14-6.5]    0.10 [ND-0.32]  3.5 [0.24-7.6]   9

                                                                                                                                          

    Table 3f (2) (continued)

                                                                                                                                          
                                                      Phenolic residues
                                                                                                              
                                                                          3-hydroxy-                              DBA
                   Crop           7-phenol            3-keto-7-phenol     7-phenol            Total phenols                      Ref.
                                                                                                                                          

                   Green grass    0.29[0.06-0.52]     0.26[0.10-0.69]     0.26[ND**-0.52]     0.82[0.59-0.17]     1.3[ND-2.4]    III-A
                                                                                                                                 23,
                   Green clover   0.28[0.02-0.85]     0.39[ND-1.14]       0.25[ND-1.40]       0.91[0.02-3.07]     1.4[0.4-2.9]   24,

                   Grass hay      0.50-[0.21-1.15]    0.76[0.16-2.42]     1.04[0.18-2.39]     2.30[0.79-5.19]     2.4[0.5-4]     27

                   Clover hay     0.82[0.05-2.06]     0.96[0.03-1.86]     0.43[ND-1.01]       2.21[0.05-3.97]     3[0.8-6.2]
                                                                                                                                          
    *    All single applications of 4EC formulation.
    **   ND = non-detectable: <0.03 mg/kg carbamates and 0.01 mg/kg phenols in green; <0.05 mg/kg carbamates and 0.02
         mg/kg phenols in hay; <0.1 mg/kg DBA in all.
    ***  Max. is total for any one study.

    Table 3f (3)

                                                                                                                       

    Country,       Application                                                  Residues, mg/kg
    year,          rate,*         No. of         Interval,                                                             
    crop           kg a. i ./ha   Samples**      Days           Carbosulfan         Carbofuran          Ref.
                                                                                                                       

    USA,
    1981,
    Clover         0.56

    seeds                            3              0           1.8 [0.51-3.2]      0.07[0.03-0.17]     III-A
                                     3              3           0.72 [0.18-1.7]     0.22[ND-0.66]       28
                                     3              7           0.17 [ND-0.40]      0.11[ND-0.23]
                                     3             14           0.26 [0.04-0.74]    0.20[ND-0.55]
                                     3             21           0.16 [ND-0.30]      0.16[ND-0.37]
                                     2             28           0.12[0.04-0.24]     0.16[0.09-0.23]

    stems                            3              0           28.3 [8.4-63.6]     1.6 [0.77-3.4]
                                     3              3           14.1 [2.0-33.6]     1.5 [0.38-3.8]
                                     3              7           12.1 [0.34-35.4]    2.0 [0.09-5.1]
                                     3             14           4.3 [0.75-7.1]      1.5 [0.21-2.7]
                                     3             21           2.1 [0.45-5.8]      0.91 [0.11-1.5]
                                     2             28           3.6 [0.87-6.6]      2.0 [0.35-3.9]
                                                                                                                       

    * Single application of 4EC formulation.
    ** Two or more analyses on each sample.
    ND = not detected = <0.03 mg/kg for carbosulfan and <0.02 mg/kg for carbofuran.

    Table 3g.  Residues of carbosulfan and metabolites in alfalfa resulting from supervised trials

                                                                                                                                      

                                                                             Residues, mg/kg***                        Ref. II-13
    Country,         Application                                                                                     
    year,            rate,          No. of    Interval,                                  3-Keto-        3-Hydroxy-     Total
    crop             kg a.i./ha     Samples   days         Carbosulfan    Carbofuran     carbofuran     carbofuran     carbamates
                                                                                                                                      

    USA (10 states
    15 trials) ,
    1980-81,
    Alfalfa
    green            0.28 (ground)  11        7            0.43           0.11           0.02           1.5            2.1
                                                           [0.40-1.2]     [<0.03-0.25]   [<0.05-0.18]   [0.29-3.3]     [0.47-4.4]

                     0.56 (ground   16        14-15        00.25          0.09           0.02           2.9            3.2
                     or air)                               [<0.02-0.87]   [<0.03-0.22]   [<0.05-0.15]   [0.55-6.2]     [0.65-7.3]

    hay              0.28 (ground)  11        7            0.62           0.57           0.05           4.8            6.0
                                                           [0.10-2.6]     [<0.05-2.1]    [<0.05-0.35]   [1.5-9.8]      [1.7-12.8]

                     0.56 (ground   16        14-15        0.39           0.43           0.05           8.6            9.4
                     or air)                               [<0.05-1.6]    [<0.05-1.2]    [<0.05-0.34]   [0.88-23.0]    [1.2-25.5]
                                                                                                                                      

    Table 3g. (continued)

                                                                                                                                      

                                                                    Phenolic residues
                                                                                                                                      
                                                                    3-Keto-       3-hydroxy-
                                                      7-Phenol      7-phenol      7-phenol      Total          DBA            Ref.
                                                                                                                                      

    as above         0.28                     7       0.13          0.34          0.22          0.70           1.8            II-2,
    green                                             [0.02-0.28]   [0.10-0.65]   [0.03-0.56]   [0.15-1.3]     [<1-3.1]       4,8,9

                     0.56                     14      0.25          0.62          0.50          1.40           3
                                                      [0.06-0.68]   [0.17-1.30]   [0.08-2.10]   [0.31-4.10]    [<1-8.4]

    as above         0.28                     7       0.52          1.20          1.30          3.10           3.9
    hay                                               [0.08-1.30]   [0.45-3.20]   [0.09-4.10]   [0.66-8.50]    [<3.7.1]

                     0.56                     14      0.82          1.90          2.2           5.00           6.2
                                                      [0.11-2.30]   [0.22-4.40]   [0.25-5.70]   [0.77-11.00]   [<3.14]
                                                                                                                                      

    * All single applications of 4EC formulation.
    ** Most samples in duplicate
    *** <= below limit of detection

    Table 3g (2)

                                                                                                                                        

                                                                              Residues, mg/kg*
    Country,          Application                                                                                            
    year              rate,            Interval,                       3-Keto-             3-Hydroxy-          Total             Ref
    crop              kg a.i./ha       days        Carbosulfan         Carbofuran          carbofuran          carbamates        II-2
                                                                                                                                        

    USA (8 trials),
    1979,
    Alfalfa           0.56
                      1 application
    green             at each of 3        0        26.0 [13.9-62.1]    4.5 [1.9-9.4]       3.0 [0.73-8.3]      33.5 [16.9-73.0]
                      cuttings 4EC        7        1.1 [0.12-4.3]      0.33 [0.07-0.99]    4.5 [0.89-9.6]      6.0 [1.4-10.8]
                      formulation        14        0.32 [0<02-2.5]     0.20 [<0.03-1.4]    3.0 [0.48-8.1]      3.6 [0.58-9.6]

    hay                                   0        48.2 [0.09-141]     8.5 [0.66-34.0]     6.9 [0.79-21.0]     63.6 [4.9-185]
                                          7        2.1 [<0.05-11.9]    1.1 [<0.05-6.1]     10.5 [0.19-59.7]    13.7 [0.70-64.1]
                                         14        0.46 [0.05-2.6]     0.46 [0.05-1.9]     8.1 [0.88-22.8]     9.1 [1.1-25.3]
                                                                                                                                        

                                                                    Phenolic residues, mean and [range]
                                                                                                                                        
                                                                                           3-Hydroxy-                            Ref.
                                                   7-Phenol            3-Keto-7-phenol     7-phenol            Total             II-1
                                                                                                                                        

    green                                 0        1.0 [0.54-1.3]      0.08 [0.06-0.12]    0.08 [0.05-0.12]    1.2 [0.68-1.5]
                                          7        0.43 [0.24-0.68]    1.1 [0.70-1.4]      0.70 [0.48-0.85]    2.2 [1.4-2.7]
                                         14        0.24 [0.04-0.85]    0.78 [0.10-1.7]     0.40 [0.04-1.3]     1.4 [0.18-4.2]

    hay                                   0        2.5 [1.3-4.0]       0.61 [0.11-1.7]     0.48 [0.12-1.4]     3.6 [1.5-7.1]
                                          7        1.0 [0.57-1.7]      2.4 [1.8-3.7]       1.6 [1.0-2.3]       5.0 [3.4-7.7]
                                         14        0.59 [0.09-1.6]     1.6 [0.14-3.4]      0.97 [0.09-2.1]     3.2 [0.32-6.1]
                                                                                                                                        

    * <= below limit of detection.

    Table 3g (3)

                                                                                                                                             

                                                                          Residues, mg/kg**
                                                                                                                                             
                                                                                                        Total
    Country,          Application                                                                       cholinesterase
    year,             rate,       Interval,                               3-Keto-        3-Hydroxy-     inhibiting
    crop              kg a.i./ha  days      Carbosulfan    Carbofuran     carbofuran     carbofuran     metabolites      DBA            Ref.
                                                                                                                                             

    USA (10 states
    11 trials) ,
    1981-82,
    Alfalfa           0.84        21        0.08           0.05           0.02           1.7            1.8              1.6            II-5,
    green             (ground or            [<0.03-0.44]   [<0.03-0.23]   [<0.03-0.28]   [<0.03-5.1]    [0.14-5.3]       [ND-5.2]       11,
                      air)                                                                                                              14

    hay                           21        0.12           0.12           0.05           3.5            3.7              3.5
                                            [<0.05-1.1]    [<0.05-0.69]   [<0.05-0.54]   [0.27-16.6]    [0.27-17.8]      [0.04-15.1]
                                                                                                                                             

    Table 3g (3) (continued)

                                                                                                                                             

                                                                                                                  Total
                                                                                                                  cholinesterase
                                                                                    3-Hydroxy-     3-Keto-        inhibiting
                                            Cutting   Carbosulfan    Carbofuran     carbofuran     carbofuran     metabolites         Ref.
                                                                                                                                             

    USA (8 states),   2.1
    1982-83,          (at plant)
    Alfalfa                                 1         <0.03          0.05           1.3            0.11           1.4                 II-15
    Spring                                                           [<0.03-0.29]   [<0.05-8.1]    [<0.05-1.1]    [ND-8.8]
    green hay                     58-196    2         <0.03          <0.03          0.09           0.05           0.09
                                                                                    [<0.05-0.62]                  [ND-0.62]

                                            1         <0.03          0.06           2.1            0.03           2.2
                                                                     [<0.03-0.39]   [<0.05-11.7]   [<0.05-0.21]   [ND-12.1]
                                            2         <0.03          0.02           0.27           <0.05          0.29
                                                                     [<0.03-0.14]   [<0.05-1.9]                   [ND-1.9]

    Fall                          161-      1         <0.05          <0.05          0.03           0.01           0.05
    green hay                     346                                               [<0.05-0.14]   [<0.05-0.06]   [ND-0.20]

                                            2         <0.05          <0.05          <0.05          <0.05          ND

                                            1         <0.05          0.02           0.22           <0.05          0.24
                                                                     [<0.05-0.08]   [<0.05-0.47]                  [ND-0.55]
                                            2         <0.05          <0.05          <0.05          <0.05          ND
                                                                                                                                             

    * All single applications of 4EC formulation.
    ** <= below limit of detection.

    Table 3h.  Residues of carbosulfan and metabolites in hops and beer resulting from supervised trials

                                                                                                                  

                                                                          Residues, mg/kg
    Country,                                                                                                      
    year,                         No. of    Interval,                                    3-OH-
    crop           Application    Samples   days           Carbosulfan    Carbofuran     carbofuran     Ref.
                                                                                                                  

    W. Germany,    6 x 9.75
    1981-82,       kg a.i ./ha,     11         0           8.1            2.6            1.5            VIII-4
    hops           25 EC                                   [0.5-19.4]     [0.9-6.2]      [0.5-19]
    dry            formulation
                                    11         7           1.7            0.4            10
                                                           [0.16-3.4]     [0.05-0.9]     [0.24-21]

                                    11        14           0.9            0.4            10
                                                           [0.09-2]       [<0.05-1.6]    [0.36-22]

                                    11        21           1.6            0.3            6
                                                           [0.2-3.4]      [0.09-0.9]     [0.7-11]

                                    11        28           0.6            0.08           3.7
                                                           [0.07-2.1]     [<0.05-0.24]   [0.06-8]

    green                            5         0           2.6            0.7            1.1
                                                           [1.2-6.4]      [0.6-1.5]      [0.7-3]

                                     5         7           0.8            0.4            1.5
                                                           [0.2-3]        [<0.05-1.2]    [0.3-2.3]

                                     5        14           0.2            0.1            1.2
                                                           [0.1-3]        [<0.05-0.25]   [0.08-2.1]

                                     5        21           0.07           0.07           1.2
                                                           [<0.05-0.1]    [<0.05-0.13]   [0.6-2.8]
                                                                                                                  

    Table 3h.  (continued)

                                                                                                                  

                                                                          Residues, mg/kg
    Country,                                                                                                      
    year,                         No. of    Interval,                                    3-OH-
    crop           Application    Samples   days           Carbosulfan    Carbofuran     carbofuran     Ref.
                                                                                                                  

                                     5        28           0.08           0.05           1.1
                                                           [<0.05-0.2]    [<0.05-0.06]   [0.7-2.5]

    W. Germany,    as above
    1982,
    Spent hops                       2        21           [<0.05]        [<0.05]        [<0.05]

    beer                             4        21           [<0.05]        [<0.05]        [<0.05]
                                                                                                                  

    Table 3i.  Residues of carbosulfan and metabolites in rapeseed resulting from supervised trials

                                                                                                                 

                                                                         Residues, mg/kg
    Country,                                                                                                     
    year,                         No. of    Interval,                                3-OH-
    crop           Application    Samples   days        Carbosulfan    Carbofuran    carbofuran      Ref.
                                                                                                                 

    France,
    1979,
    rapeseed       1 x 0.45-0.9   8         287-304     <0.05         <0.05        <0.05          VI-2,
    (grain)        (in furrow)                                                                       VIII-7
                   5G formulation
                                                                                                                 

    Table 3  Footnotes and References

    1  No. of samples is in parenthesis after residue value if not in a separate column
    2  Two week intervals;
    3  maturity (160 days or more)
    4  3 samples
    5  10 samples
    6  Corrected for recovery
    7  Square brackets indicate range throughout Table 3, usually accompanied with mean value
       immediately above, below or to the side
    8  Residue values in parentheses are estimates, above the limit of detection, but below the
       limit of determination
    9  Total maximum residue from an individual sample within a study
    10 Residues of all three compounds were each <0.05 mg/kg in pulp. Values for fruit and peel are
       duplicates at each interval

    References: See Table 3 references in reference section.

    
         No data were available for the more leafy members of this group,
    so a group limit would not be appropriate.

    Legume Vegetables

         Only minimal data were available (on dry beans) from one country
    (Table 3b). Total carbamate residues were <0.06 mg/kg, but results
    were too few to support a limit on beans, even if approved use
    information were available.

    Citrus Fruit

         Data on more than 25 supervised trials were available to the
    meeting, but there was no information on nationally approved uses in
    either of the two countries in which the trials were conducted
    (Table 3c). Most of the data were from the U.S.A. where uses on citrus
    are proposed, but as yet unregistered. The application rates and
    number of applications in the trials are consistent with those
    permitted for experimental purposes only or in one case with the
    "suggested" 11g a.i./l water. No safety interval was available.

         In most trials samples were analyzed for carbosulfan, carbofuran,
    3-hydroxycarbofuran, 3-ketocarbofuran, total carbamates, individual or
    total phenolics and dibutylamine (DBA). In general levels of
    individual and total carbamates were relatively constant over the 0-28
    days-after-last-treatment intervals for any one group of similar
    trials. In some trials on grapefruit however, the proportion of
    ketocarbofuran increased during the 28-day trial from about 8% to 20%
    of the total carbamate. This appears to be typical of the proportion
    of 3-ketocarbofuran in citrus relative to the total carbamate residue.
    The highest residues found in any of the trials on day 0 and on day 28
    respectively were carbosulfan 1.7 and 0.46 mg/kg; carbofuran 0.63 and
    1.51 mg/kg; 3-hydroxycarbofuran 0.83 and 0.46 mg/kg; 3-ketocarbofuran
    0.1 and 0.27 mg/kg; and total carbamates 2.3 and 2.1 mg/kg. In
    general, except on the day of last application when carbosulfan was
    frequently higher, carbofuran and 3-hydroxycarbofuran were the
    predominant carbamate residues and frequently at similar levels.
    Figure 1 illustrates a typical carbamate residue profile in citrus and
    is derived from Table 3c (Ref. 1-19; average residues from five
    applications).

         As in the case of the carbamates, average phenolic and DBA
    residues were relatively constant from 0 to 28 days after the last
    treatment. The maximum total phenolic and DBA residues found in any
    trial were 0.55 and 1.8 mg/kg respectively.

         Table 15 illustrates the distribution of carbamate and phenolic
    residues in peel, edible fruit and whole mature oranges. Residues are
    shown to be almost entirely in the peel. Similar results were observed
    for lemons (FMC, 1984, 1-10) and grapefruit (FMC, 1984, I-9), although
    up to 8% of the average phenolic residues in grapefruit were in the
    edible portion. Most samples were stored at -18C although 

    FIGURE 1

    harvest-to-analysis intervals were not provided. Storage trials (see
    "Fate of Residues-In Storage") showed no carbosulfan or carbofuran
    losses after one year storage of citrus at -18C.

    Pome Fruit

         No pome fruit residue data were available from the one European
    and two Asian countries where EC and WP formulations respectively are
    approved for use (Table 1). Pre-harvest intervals were not provided
    even for these countries and information on application rates,
    although summarized in Table 1, was received too late for
    consideration. Except in one study, "suggested" application rates of
    50-75g a.i./1001 water for deciduous fruit could not be compared with
    the rates used in the trials. Residue data were available on apples
    from two European countries whose approved uses were not known, and on
    apples and pears from the U.S.A. where uses are not yet registered.
    Data are summarized in Table 3d.

         Applications were with EC and/or WP formulations which were
    applied by ground or aerially. The highest residues in any trial at 0
    and (28) days after the last application were: carbosulfan 2.5 mg/kg
    (1.6 mg/kg), carbofuran 0.5 (1.1) mg/kg, 3-hydroxycarbofuran 0.34
    (0.8) mg/kg, and total carbamates 3.3 (2.9) mg/kg. In trials in one
    country from which no O-day data were available, maximum residues even
    after 10 days were 2.3 mg/kg carbosulfan, 0.6 mg/kg carbofuran and
    0.3 mg/kg 3-hydroxycarbofuran. When included in the analyses,
    3-ketocarbofuran was not detected (<0.02 mg/kg). In general
    carbosulfan was the major residue over a 28-day interval followed in
    order by carbofuran and 3-hydroxycarbofuran.

         Where compared, residues of total carbamates were similar for WP
    and EC applications. The aerial applications indicate that carbamate
    residues increase with the number of applications and most of the
    studies indicate that they are persistent and fairly constant up to 28
    days after the last application.

         The highest total phenolic residue measured was 0.24 mg/kg. With
    average total phenolic residues of 0.12, 0.07 and 0.09 mg/kg at 0, 14,
    and 28 days respectively after the last application (FMC, 1984,
    III-1), phenolics were shown to be fairly constant from 0-28 days.
    Where compared, average individual and total phenolic residues were
    similar from WP and EC formulations.

         The highest DBA residue in any trial was 0.52 mg/kg and average
    DBA residues were relatively constant from 0-28 days after the last
    application. In one set of similar trials average DBA residues
    resulting from EC application were twice those from WP over the 28-day
    period.

         Harvest-to-analysis storage conditions were not provided in many
    cases. Storage was at -18C in the U.S. trials, but intervals were not
    stated. The U.K. samples were stored at 20C (5-29C before shipment
    to the laboratory). No information was provided for the Italian
    trials. No storage stability data were provided.

    Cereal Grains

         Residue data were available from European, North American or
    South American countries on corn, rice, sorghum and wheat (Table 3e).
    Information on nationally approved application rates was received too
    late for consideration. No information was provided on safety
    intervals.

    Maize.  Data were available from one European country whose approved
    uses were provided too late for consideration. Data were also
    available from a North American country where the use is not yet
    registered, although information on uses permitted in experimental
    programmes only was provided. In the European trials individual
    residues of carbosulfan, carbofuran and 3-hydroxy-carbofuran in mature
    grain from in-furrow 5G applications at 0.5-1.5 kg a.i./ha were
    <0.05 mg/kg (limit of determination). In whole plants, residues of
    each were <0.12 mg/kg. The 1.5 kg a.i./ha furrow rate is twice the
    maximum "suggested" granular rate.

         In the North American studies at-plant in-furrow EC applications
    were at what appears to be three times the experimental permit rate or
    suggested rate. Residues in grain were less than the limits of
    detection for carbosulfan, carbofuran, 3-hydroxycarbofuran and
    3-ketocarbofuran and hence <0.07 mg/kg for total carbamates.
    Carbosulfan residues were less than the 0.01 mg/kg limit of detection
    in grain, fodder and silage. 3-hydroxycarbofuran was the predominant
    residue in fodder and silage. The maximum total carbamate residues
    were 0.03 mg/kg and 1.6 mg/kg in fodder and silage respectively.

         Maximum total phenolic residues were <0.01, 3.5 and 1.7 mg/kg in
    grain, silage and stover respectively. Corresponding maximum DBA
    residues were <0.01, 0.03 and 0.11 mg/kg.

    Rice.  Residue data were available from one European country and one
    South American country, although no information on uses was available
    for either. Carbosulfan is registered for rice in several countries,
    but none in proximity to those from which data were available. The
    limited data show individual residues less than the 0.02 mg/kg limit
    of detection for carbosulfan, carbofuran and 3-hydroxycarbofuran
    (<0.06 mg/kg total).

         Application rates could not be compared to the "suggested"
    2.5-3.5 g a.i./box of seed (granular); 0.15-0.3g a.i. granular/10 sq.m
    seed bed; 0.75-1 kg a.i./ha granular broadcast or 0.2-0.5 kg a.i./ha
    EC foliar treatments.

    Wheat.  Limited data on residues (<0.02 mg/kg each of carbosulfan,
    carbofuran and 3-hydroxycarbofuran) but none on use were available
    from one country. A 25EC formulation is permitted in one country not
    in close proximity.

    Sorghum.  Data were available from one country in which carbosulfan
    is not yet registered. Other use information was available from
    European countries where 5G in-furrow applications are permitted, but
    not in time for consideration. In the trials for which data were
    available, application rates reflected those allowed for experimental
    purposes only, except that an at-plant 10G application was also made
    in addition to the three foliar EC applications. Maximum residues in
    grain 30-39 days after the last application were: carbosulfan 0.14,
    carbofuran 0.29, 3-hydroxycarbofuran 0.35 and total carbamates (for
    any one sample) 0.56 mg/kg. In stalks the corresponding maximum
    residues were 1.13, 0.65, 0.85 and 2.27 mg/kg. Maximum residues of
    total phenolics were 4.1 and 1.6 mg/kg for stalks and grain
    respectively, and of DBA 1.8 and 1.1 mg/kg respectively.

         Information was minimal on harvest-to-analysis storage conditions
    for cereals. In the French trials, maize samples were stored up to 9
    months at 20C. U.S. and Brazilian samples of field corn, rice and
    wheat were stored at -18C and sorghum samples at -20C but no storage
    periods were provided. Storage stability data were available only for
    corn forage (see "Fate of Residues-In Storage") where carbosulfan
    decreased by 50% and total residues by 30% within one year during cold
    storage.

    Grass Fodder

         Extensive residue data on grass (green and hay) were available
    from one country (Table 3f), but no information on approved uses (not
    even "suggested" uses). Seven to 21 days after single, ground or
    aerial applications of 4EC at 0.28, 0.56 or 0.84 kg a.i./ha to grass,
    maximum residues in green grass and (hay) were: carbosulfan 1.5
    (3.9) mg/kg, carbofuran 2.1 (12.2) mg/kg, 3-hydroxycarbofuran 2.4
    (7.2) mg/kg, 3-ketocarbofuran 0.92 (1.9) mg/kg, total carbamates 4.4
    (19.8) mg/kg, total phenolics 4.8 (8.1) mg/kg and DBA 3.8 (4.7) mg/kg.

    Legume Animal Feeds

         Data on residues in alfalfa and clover from one country, but no
    information on nationally approved or even "suggested" uses, were
    available.

    Alfalfa.  Residue data were available from 34 trials with
    0.28-0.84 kg a.i./ha EC applications by ground or air and from a
    single at-plant EC application on green alfalfa and hay (Table 3g).
    Only experimental use information was available; the trials uses were
    generally consistent with experimental permits. Data for hay were not
    corrected for moisture which varied from 4-52%, but averaged
    approximately 23%.

         Maximum residues 0-21 days after the last application over all
    the foliar treatments in green alfalfa and (hay) were: carbosulfan 62
    (141) mg/kg, carbofuran 9.4 (34) mg/kg, 3-hydroxycarbofuran 9.6
    (59.7) mg/kg, 3-ketocarbofuran (not measured in all the trials)
    0.28 (0.54) mg/kg and total carbamates 73 (185) mg/kg. Highest
    residues generally occurred on the first day and total carbamates
    decreased to about one-tenth of the initial level by 14 days.

         In general air and ground applications resulted in similar
    residues especially on green alfalfa. Residues of 3-ketocarbofuran
    were generally about 1-5% of the total carbamate residue. Data
    provided to the meeting clearly show that there was no increase in
    carbamate residue levels in second and third cuttings when there was
    on application per cutting.

         Maximum total phenolic residues from foliar applications at 0-21
    days were 4.2 and 11 mg/kg in green alfalfa and hay respectively.
    Average phenolic residues were similar from ground or air applications
    after 14 days and the data provided (Ref. II-1 Table 3g) show no
    increase in average phenolic residues 14 days after 2nd and 3rd
    cuttings. However, 0- and 7-day samples from 2nd and 3rd cuttings were
    not analyzed so no conclusion can be drawn on residue increases at
    these intervals.

         Maximum DBA residues 21 days after foliar ground or aerial
    applications were 5.2 and 15.1 mg/kg in green alfalfa and hay
    respectively.

         In general residues in green alfalfa or hay from at-plant
    applications were significantly lower than those from applications
    0-21 days before harvest. No residues of carbosulfan per se
    remained, but up to 9 and 12 mg/kg carbamate metabolites were present
    in spring green alfalfa and hay, respectively, 58-196 days after
    treatment.

    Clover.  Extensive supervised trials data were available from one
    country (Table 3f). Maximum residues on green clover and (hay) 7-21
    days after ground or aerial EC applications at 0.28-0.84 kg a.i./ha
    were: carbosulfan 1.9 (3.2) mg/kg, carbofuran 2.4 (3.6) mg/kg,
    3-hydroxycarbofuran 4.1 (14.6) mg/kg, 3-ketocarbofuran 2.9 (6.5) mg/kg
    and total carbamates 5.1 (17.1) mg/kg. The 3-ketocarbofuran was
    generally <5% of the total carbamate residues. Maximum residues of
    carbosulfan and carbofuran were 3.2 and 0.17 mg/kg respectively in
    clover seeds and 63.6 and 3.4 mg/kg respectively in the stems on the
    day of application. Carbosulfan residues decreased to about one-tenth
    of their initial levels by day 28 while carbofuran residues remained
    relatively constant.

         Maximum total phenolic residues in green clover and hay in any
    trial were 3.1 and 9 mg/kg respectively, while maximum DBA residues
    were 4.9 and 21 mg/kg.

         Harvest-to-analysis storage periods for alfalfa and clover were
    not provided, although macerates were stored at -18C. Field-incurred
    residues of carbosulfan in green alfalfa have been shown to be stable
    at -18C (see "Fate of Residues-In Storage").

    Oilseed

         Limited data on residues in rapeseed resulting from an in-furrow
    granular application were available from one country. Residues of
    carbosulfan, carbofuran and 3-hydroxycarbofuran were each less than
    the 0.05 mg/kg limit of determination (Table 3i). No information on
    uses was available.

    Unclassified Commodities

    Hops.  No information on registered or even "suggested" uses was
    available. Substantial residue data from one country were available on
    green and dry hops, spent hops and beer (Table 3h). Except on the day
    of last application, when carbosulfan was the major residue,
    3-hydroxycarbofuran was the predominant residue over the 28-day
    period. Maximum residues of carbosulfan, carbofuran and
    3-hydroxycarbofuran respectively ranged from 19.4, 6.2 and 19 mg/kg in
    dry hops on the day of last application to 2.1, 0.24 and 8 mg/kg after
    28 days. Corresponding levels on green hops ranged from 6.4, 1.5 and
    3 mg/kg on the day of last application to 0.2, 0.06 and 2.5 mg/kg
    after 28 days. Residues of each compound were less than the 0.05 mg/kg
    limit of determination in spent hops and beer.

    FATE OF RESIDUES

    General

         The fate of carbosulfan has been investigated in plants,
    animals, soil, water and light and in storage under a variety of
    conditions. In general, carbosulfan, carbofuran, 3-hydroxycarbofuran
    and 3-ketocarbofuran are the principle carbamate residues in plants
    with relative amounts varying from crop to crop and with time.
    Phenolics and dibutylamine contribute an analytically significant part
    of the total residue.

         The fate in non-food animals is considered under "Biochemical
    Aspects". This section describes the fate in goats and poultry.
    Residues are rapidly excreted from goats, primarily in the urine.
    The principle poultry tissue residues in decreasing order are
    3-hydroxycarbofuran, the 3-keto-7-phenol and 
    3-hydroxy-N-hydroxymethylcarbofuran. No residues of carbosulfan or
    carbofuran were detected. Residues in goats and eggs were not
    identified.

         The names and structures of some carbosulfan-related compounds
    are listed in Figure 2.

    In animals

    Goats.  The distribution of radioactive residues from 
    14C-ring-labelled carbosulfan was studied in the urine, faeces,
    blood, milk, expired air and tissues of two lactating goats dosed
    twice daily by gelatin capsule for seven days (Huhtanen, 1979; Wu,
    1980). The doses were equivalent to average daily dietary carbosulfan
    intakes of
    4.43 ppm for goat I and 11.4 ppm for goat II. The distribution of
    excreted and retained radioactivity is shown in Tables 4 and 5.

         Residues in whole milk were directly related to the dose and
    became level by day three in both goats. Similar levels were found in
    skim milk. Maximum levels in the cream of animals I and II were 25.8
    and 69.9 g/l respectively. Residue levels in blood were also directly
    related to the dose and increased throughout the 7-day test period,
    ranging from 3.6 to 13.1 g/l for goat I and from 8.9 to 29.8 g/l for
    goat II.

         It can be seen that maximum tissue residues occurred in kidney
    and liver with significantly less in fat and muscle.

         Two goats were dosed twice daily by capsule for ten days with
    14C-carbosulfan labelled in the C-1 position of the dibutylamine
    group (Wilkes and Wargo, 1981; Wu 1981). The total daily dose was
    10.1 mg/kg, equivalent to approximately 10 ppm in the diet. The
    distribution of residues in urine, faeces, blood, expired air, milk
    and tissues was determined in goat I which was sacrificed two hours
    after the last dose. Milk residues in goat II were monitored and
    tissues were analyzed after sacrificing 3.75 days after the last
    dosing. This provided data on the loss of residues after cessation of
    dosing. Results are shown in Tables 6 and 7.

         It is obvious that most of the radioactivity is excreted in the
    urine with some excretion in the faeces. Residues in the whole milk of
    both animals became steady on day three at 279 and 330 g/l for goats
    I and II respectively. In goat II residues declined to 24.6 g/l 3.75
    days after the last dose.

         As in other studies, 14C residues in blood increased throughout
    the dosing period and, as in the case of milk, decreased (from 119 to
    68.4 mg/l) during the 3.75-day withdrawal period.

    FIGURE 2

    FIGURE 2a;V084PR22.BMP

    Table 4.  Radioactivity excreted by goats dosed with ring-14C 
              carbosulfan

                                                                     

                                  14C, % of total administered dose
    Sample                        Goat I              Goat II
                                                                     

    urine                         81.5                79.8
    faeces                        2.3                 2.8
    milk                          0.6                 0.6
    expired gases                 2.1                 2.6

    Total Recoveries              86.5                85.9
    (adjusted)*

                                                                     

    * Adjusted to take into account urine losses and contamination 
      of faecal samples.


    Table 5.  Radioactivity in tissues, blook and milk of goats dosed 
              with ring-14C carbosulfan

                                                                     

                      Total 14C expressed as g/kg (ppb) carbosulfan
    Tissue                     Goat I             Goat II
                                                                     

    liver                      31.0               111.2
    kidney                     49.7               118.4
    heart                      9.9                25.2
    back muscle                4.2                16.1
    foreleg muscle             7.0                12.3
    hind leg muscle            6.2                22.7
    omental fat                5.2                6.1
    milk (maximum levels)      21.3 (mean 16)     50.8 (mean 43)
    blood (at sacrifice)       17.9               33.5
                                                                     

    Table 6.  Radioactivity excreted by goat dosed with 
              dibutylamine - 14C carbosulfan

                                                                     

                               14C excreted (goat I)
                                                                  
    Sample                                       % of
                            % of total dose     adjusted dose*
                                                                     

    urine                   68.79               79.40
    faeces                  2.28                2.69
    milk                    1.40(2)**           1.40(2)**
    expired gases           0.62                0.62

    Total Recovery          73.09               84.10
                                                                     

    *  Excluding first and final days which did not represent full 
       24-hour periods.
    ** Goat II in parenthesis

        Table 7.  Radioactivity in tissues, blood and milk of goats dosed with
              dibutylamine-14C carbosulfan

                                                                                    

                                     Total 14 expressed as g/kg (ppb carbosulfan
                                                                                    
    Tissue                              Goat I                      Goat II
                                  (2 h after last dose)      (3 days after last dose)
                                                                                    

    liver                                541.9                       341.2
    kidney                               611.4                       149.4
    heart                                 75.9                        43.4
    back muscle                           71.7                        29.3
    foreleg muscle                        77.3                        31.9
    hind leg muscle                       72.1                        34.1
    omental fat                            7.7                        27.5
    subcutaneous fat                      11.6                        19.4
    milk (maximum level)                 312.4                       363.0
    blood (last day of dosing)           109.2                       119
    blood (at sacrifice)                 109.2                        68.4
                                                                                    
    
         Also confirming other studies, residues were highest in kidney
    and slightly less in liver in the goat killed shortly after the last
    dose, whereas 3.75 days after cessation of dosing the residue in the
    kidney was less than half that in the liver. Residues in other 
    non-fatty tissues of goat II declined to about half those in goat I. It
    also appears that fat residues increased substantially during the
    withdrawal period. This is probably due to cleavage of the fat-soluble
    dibutylamine side chain.

    Poultry.  The fate of carbosulfan in laying hens dosed by capsule
    was investigated in three closely interrelated studies (Wilkes et
    al., 1981; Markle, 1982a, b). The hens were dosed daily for 14 days
    at levels equivalent to 0.5, 1.5 and 5 ppm in the diet (0.05, 0.15 and
    0.5 mg/kg body weight) with 14C-ring or 14C-dibutylamine 
    (DBA)-labelled carbosulfan. Eggs were collected throughout and the
    hens slaughtered at 6h. and 7 and 14 days after the last dose. Total
    residues were determined by oxidative combustion and identification
    was by chromatographic and spectrometric techniques. Dibutylamine was
    derivatized with phenyl isocyanate for analysis.

         In eggs, residues of both labelled compounds became steady after
    7-10 days with those from the highest dose reaching approximately 0.01
    and 0.03 mg/kg carbosulfan equivalents in egg whites and yolks
    respectively for the ring label and 0.1 and 2 mg/kg respectively for
    the DBA label. As evident in Table 8, residues were dose-dependent
    with both labels, higher in yolks than whites and higher in yolks and
    whites from the DBA label than from the ring label. On cessation of
    dosing residues from the ring label decreased to the 0.002 mg/kg limit
    of detection after 11 days, whereas residues had decreased only to
    0.06 mg/kg (yolk) by 12 days after cessation of the DBA-label feeding.

         In tissues from ring-label feeding, residues were less than the
    0.002 mg/kg carbosulfan equivalents limit of detection at all three
    dose levels after 7 days of dosing. Dose-related residues occurred on
    the first day of dose administration and from the high dose level were
    0.3 mg/kg in liver and 0.2 mg/kg in other tissues. Seven days after
    cessation of dosing residues had decreased to approximately the limit
    of detection in all tissues, with depletion fastest from liver and
    slowest from fat.

         The residue profile in liver and thigh muscle is shown in Table 9
    for the high dose level at day 0. It can be seen that the 
    3-hydroxy-7-phenol, at 16% of the total, is the major residue in
    liver, whereas 3-hydroxycarbofuran at 37% of the total is the major
    thigh muscle residue. Other metabolites occurred also, but neither
    carbosulfan nor carbofuran was found. The residue profile in eggs was
    not determined for the ring-label feeding.

        Table 8.  Maximum residues in eggs following dosing with 14C-ring- or 
              DBA-labelled carbosulfan

                                                                             

                                        Radioactivity calculated as 
                                            carbosulfan, mg/kg
                                                                             

    Dietary                         Ring Label               DBA Label
    Feeding                       White     Yolk           White     Yolk
    Level (ppm)
                                                                             

    0.5                           <0.002*   <0.002         0.014     0.18

    1.5                           <0.002     0.007         0.033     0.58

    5                              0.012     0.031         0.13      2
                                                                             

    * Limit of detection.

    Table 9.  Residues in thigh muscle and liver of chicken, 6h after dosing with
              14C-ring-carbosulfan at 5 mg/kg bw.

                                                                                        

    Fraction                              Thigh Muscle                 Liver
                                                                                    
                                       % of muscle
                                       residue       mg/kg      % of liver   mg/kg
                                                                                        

    Extractable residues

    Carbosulfan metabolites

    Carbosulfan                           -          <0.002           -     <0.002
    Carbofuran                            -          <0.002           -     <0.002
    3-OH, N-hydroxymethylcarbofuran     9.3           0.007         2.1      0.004
    3-OH-7-phenol                       7.1           0.004        16.1      0.021
    3-OH-carbofuran                    36.9           0.026         1.1     <0.002
    3-Keto-7-phenol                     6.4           0.003         2.5      0.003
    3-Keto-carbofuran                   1.7          <0.002         1.7      0.003
    7-Phenol                              -          <0.002         3.3      0.004
    Minor metabolites                   2.1          <0.002         0.5     <0.002

    Extractable unknowns
    MW > 500                            3.0           -             8.3      -
    Other                               3.6           -             2.4      -

    Total % Extractable                70.1           -            37.9      -

    Aqueous                           14.6*           -           44.9*      -

    Post-extraction solids              1.6           -           18.6*      -

    Total % recovered                  86.3           -           101.4      -
                                                                                        

    * These fractions were hydrolyzed with 0.25N HCl. Hydrolysis products include
      unknowns and 2.1% of individual tissue residues, 3-keto carbofuran,
      3-keto-7-phenol and 7-phenol.
    
         As in the case of eggs, tissue residues from the DBA label were
    significantly higher than from the ring label. From the high DBA label
    dosing at day 0 residues in liver were 1.4 mg/kg carbosulfan
    equivalent, fat 0.4 mg/kg, gizzard 0.3 mg/kg and heart, skin and
    muscle all <0.24 mg/kg. Tissue residues generally decreased over
    the test period except in skin where they were relatively constant and
    in fat where they apparently increased, especially at the lower dosing
    levels. On cessation of dosing residues decreased to <0.1 mg/kg in
    all tissues except fat and skin in which they remained constant or
    even increased slightly during the 14-day withdrawal period.

         The predominant identified 0-day tissue residue from the high
    DBA-labelled dose was dibutylamine at 0.12 mg/kg (22.5% of the tissue
    total) in muscle and 0.18 mg/kg (36.9% of the total) in liver. The
    other residues in these tissues were for the most part unidentified.
    In fat only 3.1% of the residue was DBA with another 81.7%
    characterized as extractable unknowns. This increased to 99.2% after
    14 days.

         In eggs only approximately 4% of the residue (after 9-12 days,
    yolk and white) was identified as DBA with 86% in the yolks
    characterized as extractable unknowns and 72.5% in the whites as
    either water-soluble (6.5%) or post-extraction solids (66%). It was
    confirmed by GCMS that the 14C label was incorporated into individual
    fatty acids, thus identifying a major route for the DBA side-chain
    metabolism. The same was found for chicken fat samples.

         Feeding studies were conducted with egg-bearing white leghorn
    chickens fed daily by capsule for 28 days with non-labelled
    carbosulfan and separately with non-labelled dibutylamine equivalent
    to dietary levels of 1.5 ppm carbosulfan and 10 ppm dibutylamine. Eggs
    were collected periodically throughout the study and liver, fat and
    muscle samples taken on days 28, 31 and 35 (Tilka, 1983; Leppert,
    1983a). Using analytical methods similar to those used in
    carbosulfan metabolism studies, tissue samples were analyzed by
    thermionic-nitrogen-phosphorus GLC for carbosulfan, carbofuran,
    3-hydroxycarbofuran and 3-ketocarbofuran (the latter after hydrolysis
    and ethoxylation). The limits of determination and detection were 0.05
    and 0.005 mg/kg for each compound in each tissue. Analytical
    recoveries from 0.05-0.1 mg/kg fortifications were >70% for all
    compounds in all tissues except 3-hydroxycarbofuran at 65 and 68% in
    muscle and fat respectively and 3-ketocarbofuran at 66% in fat. No
    residue was detected in any of the tissues at the 0.005 mg/kg limit of
    detection. This is consistent with results from the chicken metabolism
    studies, with labelled carbosulfan.

         The eggs (whole) were analyzed for the same compounds with limits
    of determination of 0.02 mg/kg for carbosulfan and carbofuran and
    0.01 mg/kg for 3-hydroxycarbofuran and 3-ketocarbofuran. Average
    recoveries were 70% for carbosulfan, 65% for carbofuran, 83% for
    3-hydroxycarbofuran and 66% for 3-ketocarbofuran, although individual
    recoveries were frequently only 50% (except 3-hydroxycarbofuran
    >60%). Fortification levels were generally 0.02-0.1 mg/kg. The

    analytical procedure for eggs was similar to that for tissues except
    that carbosulfan and carbofuran were initially extracted with
    acetonitrile instead of ethanol/diethyl ether/hexane. As in the case
    of tissues, no residues were detected at the 0.005 mg/kg limit of
    detection.

         Neither tissue nor egg samples were analyzed for the carbamate
    3-hydroxy-N-hydroxymethylcarbofuran which was identified as 9.3% of
    the total thigh muscle residue in chicken metabolism studies (Table
    8), nor were any samples analyzed for dibutylamine although some hens
    were fed a 10 ppm dietary level.

    In plants

    Apples.  The persistence of carbosulfan and its 
    cholinesterase-inhibiting metabolites on apple leaves after three 1.1
    kg a.i./ha foliar sprays of EC and WP formulations was investigated
    during re-entry studies (Leppert, 1982). Half-lives of carbosulfan and
    carbofuran were 4-5 and 12.5-16 days respectively: the dissipation
    followed first order kinetics. Dissipation rates were similar for the
    two formulations. Residues of 3-hydroxycarbofuran were approximately
    one-hundredth and one-tenth of the carbosulfan and carbofuran residues
    respectively at day 1 and were at about the same level (0.03 mg/cm2)
    on day 21. Residues of 3-ketocarbofuran were <0.01 mg/kg (limit of
    detection) throughout the 21-day study.

    Cotton and corn.  The fate of carbosulfan was studied in the cotton
    plant at 1, 3, 6 and 10 days after painting leaves with an
    ethanol:acetone:water solution of 14C-carbosulfan labelled in the
    dibutylamine side chain (Nishioka et al.). Surface residues and
    organosoluble, unextractable and water-soluble fractions were analyzed
    by GLC. Extraction was with buffered methanol containing N-ethylamide
    (NEM) as a sulfhydryl scavenger.

         The total radioactivity recovered ranged from 88 to 101% of that
    applied. Surface residues decreased from 13.6% of the applied a.i. at
    day 1 to 3.2% at day 10 (9.5% to 0.6% as carbosulfan). Internal
    organosoluble residues accounted for 86-96% of the applied activity,
    and by day 10 dibutylamine accounted for approximately 60% of it
    (mostly as internal residue). A significant proportion of this was
    scavenged with the NEM. Three other major internal organosoluble
    metabolites were not identified, but accounted for 9.1, 16.6 and 10.5%
    of the applied radioactivity. Carbosulfan in the internal fraction
    accounted for <1.1% of that applied.

         The absorption, translocation and metabolism of 14C-ring- and
    carbonyl-labelled carbosulfan were studied in cotton and corn plants
    following both foliage applications and stem injections (Umetsu et
    al., 1979). Carbonyl-14C carbosulfan residues remained at the point
    of application (up to 9 days) when the carbosulfan was applied near
    the tips of corn and cotton leaves, but were translocated to the whole
    leaf within 24 hr when it was applied to the base of a cotton leaf.
    Most of the radioactivity remained for up to 6 days with little

    translocation to opposite leaves. Radioactivity from stem injections
    of ring- or carbonyl-labelled carbosulfan in cotton and corn was
    rapidly translocated to the plant extremities, but only slightly to
    new growth.

         In cotton plants after stem injection of 14C-ring or 
    carbonyl-labelled carbosulfan total organosoluble radioactivity
    decreased from approximately 90% of that applied at day 1 to 55% at
    day 10, while water-soluble conjugates increased from approximately 9%
    to 40%. For both labels by day 10 carbosulfan and carbofuran were the
    major residues, at roughly the same levels, together accounting for
    approximately 50% of the applied radioactivity. 3-hydroxy-carbofuran
    (mostly conjugated) was the next major metabolite with either label,
    increasing from approximately 10% of the applied radioactivity at day
    1 to 20-30% by day 10. The three compounds therefore accounted for
    approximately 70-80% of the injected radioactivity. Other identified
    residues were 3-hydroxyphenol <3%, 3-ketocarbofuran <8% and
    N-hydroxymethylcarbofuran <5% of the injected carbosulfan.

         The same metabolites were found in corn after stem injection of
    14C-carbonyl-labelled carbosulfan, although conversion to carbofuran
    was more rapid in corn (56% of the applied carbosulfan appeared as
    carbofuran at day one) and most of the metabolites remained
    unconjugated.

         When carbonyl-labelled carbosulfan was painted on cotton leaves,
    the distribution of radioactivity after 1 and 10 days respectively was
    69 and 15% of that applied in surface residues; 18.9 and 12.5% in
    internal extracts and 11 and 66% as water-soluble conjugates. The
    surface and internal residues found are shown in Table 10.

         Similar results were found with 14C-ring-labelled carbosulfan
    except that additional metabolites in the water-soluble conjugate
    fraction were the 3-ketophenol (10% of the applied radioactivity), the
    phenol (<3%), and the 3-hydroxyphenol (<5%).

         Corn metabolism studies were conducted on the basis of in-furrow,
    at-plant soil-sprayed applications of either ring-14C or DBA-14C
    carbosulfan at an equivalent of 3.3 kg a.i./ha (FMC, 1984, V,(1)).
    Plants were grown in tanks in a greenhouse but simulating field
    conditions, and harvested at 31, 60, 110 (silage stage) and 136 days
    (maturity). Stalks, leaves, husks and grain of mature grain plants
    were analyzed. Analysis of free and (after HC1 hydrolysis) conjugated
    residues was by HPLC and scintillation counting. The dibutylamine
    fraction was reacted with phenyl isocyanate before analysis.

         In the ring study the major residues (combined conjugates and
    non-conjugates) were as shown in Table 11.

        Table 10.  Residues from foliar application of 14C-carbonyl 
               carbosulfan to cotton

                                                                          

                                              % of applied radioactivity
                                                                          
    Residue                                   Day 1          Day 2
                                                                          

    Surface
    Carbosulfan (free)                         18.1            1.6
    Carbofuran (mostly free)                   49.2           12.6
    3-hydroxycarbofuran                        19.6           62.1
    (mostly conjugated)

                                               86.9           90.7

    3-ketocarbofuran                                  <2%
    N-hydroxymethylcarbofuran                         <5%
    3-hydroxy-N-hydroxymethylcarbofuran               <0.7%

                                              Day 1          Day 10
    Internal organosoluble
    carbofuran                                 14              7.9
    carbosulfan                                 3.4            1.7
    others (each)                              <1             <1.4
                                                                          
    


        Table 11.  Residues in corn from soil treatment with ring-14C-labelled carbosulfan

                                                                                                             

                                                                  % of recovered radioactivity
                                                                         Interval (days)
                                                                                                             
    Residue                                      31        60        110       136
                                                                                                             
                                                                               Stalks
                                                                               &
                                                                               Leaves    Husks     Grain
                                                                                                             

    3-hydroxycarbofuran                          24.9      22.3      13.6      12.2      10.3
    carbofuran                                   23.8      16         2.6       1.7       0.2
    3-keto-7-phenol                               4.8      15.1      11         9.7       6.7
    3-ketocarbofuran                              3.2       3.1       1.2       2.1       2.9
    3-hydroxy-7-phenol                            2.2       2.1       6.7       4.7       9.8
    7-phenol                                      0.5       3.2       3.7       2.1       3.1
    3-hydroxy-N-hydroxymethylcarbofuran           0.3       0.6       -         -         -
    unidentified (organosoluble)1                18.5      18.5      15.3      16.9       8.6
    Total organosoluble                          78.2      80.9      55.5      49.4      42.9        6.4

    Total 14C expressed as carbosulfan mg/kg     20         6.4       4.4      25.1       1.8        1.1
                                                                                                             

    1  No one compound exceeded 6.5%
    


         Carbosulfan, its keto and hydroxy metabolites and its sulphone
    and keto sulphone (also free) were each <0.02%, and were detectable
    only at the 31-day interval. Carbofuran and its 3-hydroxy metabolite
    were mostly (>60%) unconjugated at 31 days, but conjugated or bound
    residues were predominant by the silage stage.

         In the study with DBA-labelled carbosulfan total 14C expressed
    as carbosulfan ranged from 3.6 mg/kg at 31 days to 1.2 mg/kg at 110
    days. Non-conjugated metabolites in corn plants ranged from 40% of the
    total radioactivity at 31 days to 19% in mature stalks and leaves.
    Dibutylamine was the major residue ranging from 31% at 31 days to 8%
    in mature plants with none in the husks or grain.

         Carbosulfan and its keto, hydroxy, and sulphone metabolites
    occurred only at 31 days with residues of carbosulfan 0.3%,
    carbosulfan sulphone 0.4% and 3-ketocarbosulfan sulphone 2% of the
    total recovered activity.

         At the silage and mature stages DBA was the only residue
    identified (9.3 and 7.6% of the recovered radioactivity respectively).
    In husks and grain over 90% of the recovered radioactivity was polar
    or bound unidentified residue.

         Thus, these corn studies indicate that carbofuran, its 3-hydroxy
    metabolite and dibutylamine are the predominant identified residues in
    corn from soil treatments with only low levels of parent compound and
    its sulphur-containing metabolites in immature plants.

    Alfalfa.  Tank-grown alfalfa was foliarly treated under simulated
    field conditions with either ring-14C or DBA-14C labelled carbosulfan
    as an emulsifiable concentrate at a rate equivalent to 0.5 kg a.i./ha.
    Ring-14C carbofuran was similarly applied for comparison, but a
    flowable formulation was used. In each case residues were
    characterized, identified and quantified at 7 and 14 days. After an
    initial methanol/phosphate buffer extraction, samples were separated
    into non-polar and polar fractions for analysis by scintillation
    counting or HPLC. Conjugates were hydrolyzed with 0.25 N HC1 and
    C-dibutylamine was derivatized with phenyl isocyanate to permit HPLC
    analysis (Bixler, 1982).

         The 14C-carbofuran study demonstrates that non-conjugated
    carbofuran is the major residue at 7 or 14 days, accounting for
    approximately 46% of the recovered radioactivity. The next most
    abundant is 3-hydroxycarbofuran, approximately 14% at 14 days, mostly
    as a conjugate. Combined unidentified conjugates and non-conjugates
    accounted for 13.1 and 12.9% of the recovered radioactivity at 7 and
    14 days respectively (each compound 44%). Unidentified water-solubles
    and unextractables together accounted for another 17%. Total carbamate
    residues (conjugated and free) accounted for 60% of the recovered
    radioactivity (50% of that applied). Phenols accounted for the rest of
    the identified residues.

         In the 14C-DBA study, free carbosulfan at 46.8 and 26.3% of the
    recovered radioactivity at 7 and 14 days respectively was the major
    residue. Dibutylamine at 14.3% and 38% at the same intervals was the
    major metabolite, followed by free 3-hydroxycarbosulfan at 1.7 and
    1.5% respectively. Other identified non-conjugated carbamate
    metabolites were each <1% at both intervals. Conjugated compounds
    were not identified. Unidentified non-conjugates were up to 18.7%
    (each <6.5%) and unidentified water-solubles and non-extractables up
    to 17 and 5% respectively, depending on the interval, with 
    water-solubles decreasing and non-extractables increasing from 7 to 14
    days.

         In the 14C-ring study, 72% of the recovered respectively was
    identified at 7 days, but only 50.2% at 14 days. Total carbamate
    residues (free and conjugated) decreased from approximately 64% of the
    recovered 14C at 7 days to 40% at 14 days while phenolics and
    unidentified residues increased. The identified residues at 7 and 14
    days are listed in Table 12.

         Unidentified residues (after 7 and 14 days) were characterized as
    combined conjugates and non-conjugates 11 and 22.7%, water-solubles
    5.6 and 10.9% and non-extractables 11.2 and 16.2% at 7 and 14 days
    with no individual conjugate exceeding 3.1 and 7.5%.

         Comparison of the flowable 14C-carbofuran and 14C-ring-labelled
    carbosulfan studies indicates that carbosulfan was degraded more
    rapidly, possible because there was more penetration by the EC
    formulation.

    Rice.  Tank-grown rice was treated via the soil, under greenhouse
    conditions simulating field conditions, with 14C-ring labelled
    carbosulfan and carbofuran. Application was at rates equivalent to
    1.1 kg a.i./ha carbosulfan and 1.0 kg a.i./ha carbofuran. Grain heads
    were also treated with carbosulfan only by syringe at 2 Ci/head 148
    days after the soil treatment (Capps, 1980a). In all cases application
    was in ethanol solution. Tanks were flooded after ethanol dissipation
    and transplanting of 2-week-old plants. Plants from the soil
    application were harvested at 11 and 30 days after treatment (15 days
    for carbofuran). Grain was sampled 45 days after the grain head
    treatment. Combined conjugated and non-conjugated residues in the
    plants from the soil treatment and in the grain from the grain head
    treatment from carbosulfan applications are shown in Table 13.

         From the soil application carbosulfan is evidently rapidly
    degraded to carbofuran which is translocated and metabolized.
    Carbofuran and its major metabolite 3-hydroxycarbofuran decline with
    time while other metabolites, especially phenolics, increase. Even low
    levels of the parent compound are taken up in time, although not
    detectable initially. As would be expected, conjugated residues
    increase with time. Carbamates accounted for 69% of the recovered
    radioactivity at 11 days in the plants and 56% in the grain. Of the
    recovered grain residues 94.6% were polar non-extractables but
    residues were too low for identification.

    Table 12.  Residues from foliar application of 14C-ring 
               carbosulfan to alfalfa

                                                                     

    Residue                             % of recovered radioactivity

    Major                                      Day 7        Day 14
                                                                     

    3-hydroxycarbofuran (conjugated)           19.3          6.1
    carbosulfan (free)                         14.3          5.9
    carbofuran (free)                          11.4          8.8
    3-hydroxycarbofuran (free)                  8.8          9.1

    Minor
    carbofuran (conjugated)                     3.2          1.6
    3-keto-7-phenol (conjugated)                3.2          5
    3-ketocarbofuran (free)                     2.4          2.5
    3-hydroxy-7-phenol (free)                   2.1          1.2
    3-keto-7-phenol (free)                      1.6          1.0
    3-ketocarbofuran (conjugated)               1.6          1.4
    carbosulfan sulphone (free)                 1.2          1.6
    7-phenol (conjugated)                       0.8          4.1

    Trace (<1%)

    3-keto carbosulfan (free), hydroxycarbosulfan (free) and 
    3-hydroxy-N-hydroxymethylcarbofuran.
                                                                     

        Table. 13.  Residues in rice plants and grain from soil and grain head treatment 
                with 14C carbosulfan

                                                                                    

                                                     Plants             Grain (head
    Residue                                     (soil treatment)        treatment)

                                               11 days     30 days      45 days
                                                                                    

    carbofuran                                  45.3        12           29.1
    3-hydroxycarbofuran                         20.2         9.4          7.7
    3-keto-7-phenol                              3.3         7.6          4.3
    3-keto-carbofuran                            2.1         0.9          2.3
    3-hydroxy-7-phenol                           1.6         1.7          1.8
    7-phenol                                     1.2        13.6          2.2
    desmethyl-carbofuran                         1.1         2.6          2.2
    3-hydroxy-N-hydroxymethylcarbofuran          0.1         0.6          0.4
    carbosulfan                                  0           0.2          5.7
    N-hydroxymethyl-3-ketocarbofuran             0           0            1.9
    3-hydroxy-7-phenol                           -           0            1.8
    carbosulfan sulphone                         -           -            1.7
    3-hydroxycarbosulfan                         -           -            1.0
    others                                       6.7a       17.2         11b
    aqueous                                      1.7        15.4          2
    non-extractable (or bound)                  16.5        18.4         44.5c
                                                                                    

    a  none exceeded 2.2%
    b  none exceeded 3.2%
    c  9% carbofuran, 17.8% bound, others <5%
    
         More metabolites were identified in head-treated grain than in
    plants from the soil treatment. The major products were similar, but
    the proportion of carbosulfan (mostly free) was much higher in the
    grain. The major residues in rice plants were shown to be similar at
    11 or 15 days whether carbosulfan or carbofuran was used in the soil
    treatment.

         In whole-plant autoradiography studies (Capps, 1980b) carbosulfan
    and carbofuran showed the same movement with residues concentrating in
    leaf tips and roots after soil treatment with the 14C-ring-labelled
    compounds. When 14C-dibutylamine-labelled carbosulfan was used
    however, radioactivity was evenly distributed throughout the leaves.
    The major soil degradation products carbofuran and dibutylamine
    initially accumulated in young plants. The similarity of distribution
    could be accounted for by the initial degradation to carbofuran and
    its metabolites. This would be consistent with the study described
    above (Capps, 1980a) and would indicate little if any systemic
    penetration of rice by carbosulfan per se from soil application.

         In another 14C study carbosulfan labelled in the dibutylamine
    group was applied to soil in which rice seedlings were grown under
    simulated field conditions (greenhouse), or as a foliar application to
    rice plants. The soil application rate was the same as in the study
    with ring-labelled carbosulfan. Planting and sampling were similar
    with the same 11- and 30-day harvest intervals. Separation and/or
    analyses were by GLC, HPLC and sintillation counting (Capps, 1980c).

         From the soil treatment 76 and 81% of the plant radioactivity was
    non-extractable at 11 and 30 days respectively. The non-extractables
    were not identified in the 11-day samples but, after hydrolysis,
    dibutylamine accounted for 3.3% of the recovered radioactivity at 30
    days. At 11 days, of the 24% extractables only carbosulfan and
    dibutylamine were identified (0.7 and 2.5% respectively of the total
    recovered radioactivity or together 13% in that fraction). From the
    foliar treatment, 92% of the recovered radioactivity at 30 days in the
    mature grain was unidentified non-extractable residue.

         In grain from the foliar treatment, radioactivity was 54%
    extractable and 40% non-extractable at 30 days. 15.6% of the
    extractable radioactivity recovered from the grain was carbosulfan and
    39.6% was dibutylamine. Other carbamates (sulphenylated) and unknowns
    each accounted for <2.0%.

    Soybean.  Potted soybean plants were grown in soil treated with
    ring-14C or DBA-14C labelled carbosulfan under greenhouse conditions.
    Immature plants were harvested for analysis at 30 and 60 days and
    soybeans at maturity. The residues found are shown in Table 14.


        Table 14. Residues from treatment of soybeans with 14C carbosulfan

                                                                                                  
                                                         % of recovered radioactivity
                                                                                                  
                                                     Ring label                   DBA label
                                                                                                  
                                            30-day   60-day     Mature         30-day   60-day
                                            plants   plants     beans          plants   plants
                                                                                                  

    carbofuran                               27.7      9.7       -
    3-hydroxycarbofuran                      20.1      8.6       0.5
    3-keto-7-phenol                          13.8     24.2       4.3
    3-hydroxy-7-phenol                        5.9      2.2       2.1
    7-phenol                                  3.7      7.3       0.5
    3-keto-carbofuran                         2.1      1.1       -
    3-hydroxy-N-hydroxymethylcarbofuran       0.6      0.3       -
    carbosulfan metabolites                    ND1      ND       -
    3-ketocarbosulfan sulphone                -        -         -              4
    carbosulfan                               -        -         -              0.4      0.02
    unidentified                              7.42    15.42      8.83           9.14     7.74
                                                                                                  

    1  ND = none detected by HPLC
    2  Non-conjugated and conjugated, none >3.2%
    3  conjugates, none >2.8%
    4  non-conjugates, each <3.2%
    

         These data confirm that carbofuran and its 3-hydroxy metabolite
    are the major carbamate plant residues from soil application, with
    negligible residues of carbosulfan and its metabolites suggesting
    little systemic action. Dibutylamine was not detected in this study.
    Carbofuran was mostly non-conjugated, whereas the 3-hydroxy metabolite
    was more or less equally non-conjugated and conjugated.

    In soil

    Adsorption and leaching.  In adsorption/desorption experiments,
    14C-labelled carbosulfan, carbofuran and dibutylamine were compared
    with DDT and 2,4-D in four soils ranging from fine sand to sandy clay
    loam with pH values between 5 and 7 (Robinson, 1980). Carbosulfan was
    found to be more tightly bound in each soil than 2.4-D and carbofuran,
    although not as tightly as DDT. Carbofuran was slightly less strongly
    bound than 2,4-D in silt or clay loam and fine sand and dibutylamine
    more bound than 2,4-D, but significantly less than carbosulfan. These
    results were generally confirmed by thin layer investigations,
    although carbosulfan was degraded to carbofuran on the silt and clay
    loam plates (Robinson, 1981).

         The leaching of seven-day-aged carbosulfan residues in fine sand,
    sandy loam and silt loam was investigated in soil columns (Reynolds,
    1982). Soil radioactivity was shown to be fairly evenly distributed
    throughout the bottom portion of the 2.5  30 cm columns after eluting
    the fortified soil plug into similar untreated soil below.
    Approximately 98% of the recovered radioactivity was retained by the
    silt loam after elution with 250 ml water, while in fine sandy and
    sandy loam 46.7 and 73.8% respectively were eluted, with most of the
    remaining radioactivity in the treated soil plugs. There appeared to
    be no relation between the extent of elution and soil texture, organic
    matter or pH. The propensity for elution was, oddly and perhaps
    coincidentally, inversely related to cation exchange capacity.

         Carbofuran was shown to be the major residue in aged soil as well
    as in eluates, with only low levels of carbosulfan (<0.8% of the
    recovered radioactivity) in soil and none in eluates. Low levels
    (<0.6% of recovered radio activity) of 3-ketocarbofuran were
    detected in eluates and up to 2% of the recovered activity in soil and
    eluate was the 7-phenol. Low levels of unidentified extractable
    metabolites were also detected in column soil or eluate, but
    constituted <2.1% of the recovered activity. This would probably
    include a number of carbosulfan or carbofuran metabolites which were
    identified in the aged soil before elution, no one of which exceeded
    the 1.6% of 7-phenol and 1.4% of carbosulfan sulphone which were among
    those identified. These studies confirm earlier results showing low
    potential for carbosulfan leaching but substantial degradation to and
    elution of its metabolites, primarily carbofuran.

         The retention of carbosulfan was confirmed by citrus field
    studies in which soil samples were analysed after four applications of
    carbosulfan (two at 4.2 kg a.i./ha and two at 1.1 kg a.i./ha, in a
    2.5EC formulation) (Leppert, 1983c). The study showed that carbosulfan
    remained in the topsoil and/or adhered to sediments. Carbofuran
    penetrated 1.2m of sand to an underlying clay layer, although at low
    levels.

    Dissipation of residues.  The dissipation of carbosulfan in soil has
    been investigated following applications to an alfalfa field, citrus
    groves and an apple orchard. Degradation under aerobic and anaerobic
    conditions was also studied.

         In the alfalfa study silt loam and clay soils were analysed for
    carbosulfan and carbofuran at 0-15 and 15-30 cm depths at various
    intervals after three 1.1 kg a.i./ha 4EC applications, (one
    application per cutting) (Leppert, 1981a). The highest carbosulfan
    residue at any interval, depth or cutting was 0.18 mg/kg after a
    second cutting in the 0-15 cm sample on the day of application. The
    corresponding carbofuran residue was 0.09 mg/kg. The maximum
    carbofuran level at any interval or cutting was 0.12 mg/kg (second
    cutting, 0-15 cm depth, 7-day interval). The maximum total of the two
    combined in any sample was 0.27 mg/kg. After 30 days carbosulfan was
    <0.05 mg/kg in all 0-15 cm samples and carbofuran was <0.06 mg/kg
    (only one sample exceeded 0.05 mg/kg). All 15-30 cm samples contained
    <0.05 mg/kg carbosulfan and carbofuran except one which contained
    0.1 mg/kg carbofuran. There was no evidence of residue accumulation
    from one cutting to the next.

         Carbosulfan and carbofuran were determined in the sandy soil of
    citrus groves after a single treatment with a 4EC formulation at
    1.0 kg a.i./ha and after two additional applications at 4.1 kg a.i./ha
    followed by a 1.0 kg a.i./ha application (Leppert, 1981b). The highest
    carbosulfan residue from the single treatment was 0.34 mg/kg in
    0-15 cm soil on day 0 and this had decreased to <0.05 mg/kg (limit of
    determination) by 28 days. The maximum carbofuran residue was
    0.14 mg/kg after 3 days. Both compounds were <0.01 mg/kg at all
    intervals in 15-30 cm soil.

         After the last 3 treatments, the highest O-day carbosulfan
    residue in 0-15 cm soil was 0.09 mg/kg, lower than after the single
    application, but 3-day carbofuran was higher (up to 0.38 mg/kg).
    Residues were also higher in 15-30 cm soil with maxima of 0.02 mg/kg
    carbosulfan and 0.07 mg/kg carbofuran after 3 days.

         Sandy citrus grove soil was also analysed for carbosulfan and
    carbofuran after a single 15G application at 11 kg a.i./ha (Leppert,
    1981c). As might be expected because of the higher application rate
    and the type of formulation, and possibly because of the lower average
    temperatures and significantly less precipitation, residues were
    higher than in the study described above. Maximum carbosulfan and

    carbofuran residues were 21.6 mg/kg (0-day) and 4.8 mg/kg (3 days)
    respectively in 0-15 cm soil samples, with a maximum total in any one
    sample of 23 mg/kg. Maximum residues after 56 days were carbosulfan
    0.46, carbofuran 0.92 and total 1.36 mg/kg. Residues were lower in
    15-30 cm soil samples. To minimize storage decomposition (see "In
    storage") all samples were analysed within three weeks of receipt as
    compared to 3-166 days (60 days for three applications) in the alfalfa
    study. This too could have contributed to higher residues.

         Carbosulfan and carbofuran residues were also determined in soil
    from an apple orchard after foliar treatment 2.2 kg a.i./ha (4EC) when
    dormant, followed by three 25WP foliar applications during the growing
    season (Leppert, 1983b). No carbosulfan was carried over to the fourth
    application from the three earlier applications. In 0-15 cm soil
    samples maximum average carbosulfan residues from duplicate
    determinations decreased from 0.12 mg/kg at day 0 to 0.04 mg/kg
    (0.05 mg/kg limit of determination) after 42 days, while carbofuran
    increased from 0.03 mg/kg at day 0 to 0.09 mg/kg after 21 days. Total
    average residues (of duplications) decreased only from 0.15 mg/kg at
    day 0 to 0.1 mg/kg after 42 days. Average residues were less than
    0.05 mg/kg in all 15-30 cm soil samples.

         Because the carbosulfan metabolite dibutylamine (DBA) is a
    secondary amine which is theoretically subject to nitrosamine
    formation in soil, the stability of dibutylnitrosamine in soil was
    investigated to provide information on the likelihood of this
    potential hazard (Rogers, 1982). The persistence was investigated in
    sandy loam and silt loam soils (pH 5-5.7) either unfortified or with
    added nitrate or nitrite. Dissipation was most rapid in unfortified
    soil where only 22.5% of the applied nitrosamine was recovered on day
    0, decreasing to 0.2% by day 5. Dissipation was also more rapid in
    nitrate- than nitrite-fortified soil, decreasing from 29-34% of that
    applied on day 0 to 0.9-4.1% after 7 days. The half-life was less than
    3 days in all soils. Losses were attributed to volatilization or CO2
    formation, but this was not confirmed.

         The degradation of 14C-ring- and 14C-DBA-labelled carbosulfan
    has been investigated under aerobic and anaerobic conditions. In the
    study by Markle (1981a) carbofuran was the predominant ring-labelled
    metabolite. In aerobic conditions it increased from 5-12.5% of the
    total radioactivity on day 0 to 50% after 14 days; in anaerobic from
    40-75% at day 0 to 85% after 14 days. Carbosulfan decreased from
    73-86% and 10-34% on day 0 to 2-4% and 0.5-0.7% after 28 days, in
    aerobic and anaerobic conditions respectively. Extractables had
    decreased to 37-58% (aerobic) and 76-84% (anaerobic) after 28 days,
    indicating that bound residues are slower to form under anaerobic
    conditions. 3-ketocarbofuran was the next most abundant metabolite
    under aerobic conditions, and the 7-phenol under anaerobic conditions.
    This suggests that soil binding is oxygen-dependent under aerobic
    conditions. Other carbosulfan or carbofuran metabolites were
    identified, but at significantly lower levels. The half-life of
    carbosulfan in soil was 1-5 days under aerobic conditions.

         A 1-5 day half-life of DBA-14C-carbosulfan was also observed
    under aerobic conditions (Markle, 1981b) with the rapid formation of
    CO2 or DBA. The latter rapidly binds with soil. DBA was present
    throughout the study, but did not accumulate. It was also rapidly
    formed under anaerobic conditions and accumulated, with less CO2
    formation. Unextractable residues were higher under aerobic than
    anaerobic conditions, as with ring-labelled carbosulfan.

    Residues in rotational crops.  Nine months after single applications
    of phenyl-ring-14C-labelled carbosulfan at 1.5 and 3 kg a.i./ha to
    silt loam soil under field conditions, lettuce, spring wheat and sugar
    beets were planted and grown to maturity (Capps, 1980d). The mature
    lettuce, spring wheat, and sugar beets were harvested at 60, 90 and
    120 days respectively after planting (as were immature plants at
    shorter intervals). The radioactivity expressed as carbosulfan in
    mature samples from the higher application rate was equivalent to
    0.017 mg/kg in lettuce; 0.036, 0.025 and 0.019 mg/kg in the straw,
    chaff and grain of wheat respectively, and 0.004 and 0.005 mg/kg in
    sugar beet tops and roots. Approximately half these levels were found
    at the lower application rate.

    Interreaction with soil microorganisms.  Three investigations
    considered the possible effect of carbosulfan on soil microorganisms
    or vice versa. In one (Kinne, 1982), the numbers of microbial colony
    populations were not significantly affected within 14 days after an
    application of technical carbosulfan at an equivalent field rate of
    11 kg a.i./ha to silt loam soil.

         In a second study (Froelich, 1982) the effects on nitrification
    were investigated after the application of technical carbosulfan to
    silt loam and sandy loam soils at field rate equivalents of 11 and
    110 kg a.i./ha. Nitrate levels were significantly higher in untreated
    controls than in treated samples for 28 days, which was similar at
    both rates, was attributed to the acetone solvent since it was also
    found in an acetone-treated control. The experiment was not repeated
    using a solvent which does not suppress nitrification.

         In the third study the effect on cellulose, starch and protein
    degradation in silt loam and sandy loam soils was investigated after
    applications of carbosulfan at field-equivalent rates of 11 and
    110 kg a.i./ha (Froelich and El-Nagger, 1982). No significant effects
    were observed in the silt loam, while in sandy loam degradation of
    cellulose and starch appeared to be measurably increased. Although a
    decrease might have been of concern an increase in degradation was not
    considered by the author to be an adverse effect.

    In water

         The hydrolysis rate of carbosulfan in water in the dark, buffered
    at pH 5, 7 and 9 and unbuffered, has been investigated (El-Nagger and
    Reynolds, 1982). Half-lives were 0.2, 11.4 and 18.2 hours at pH 5, 7
    and 9 respectively. The half-life in distilled water at pH 7.3 was
    18.2 hours. The main products from ring-labelled carbosulfan were
    carbofuran at pH 5 and 7 and the 7-phenol at pH 9. Low levels of other
    carbosulfan and carbofuran degradation products were also detected.
    Each was <1% of the total recovered residues at pH 5 and 7 but
    at pH 9 3-ketocarbosulfan sulphone, carbosulfan sulphone,
    3-hydroxycarbofuran and 3-ketocarbosulfan each accounted for 2-3% of
    the recovered radioactivity after 240 hours.

         In surface and ground water studies conducted in citrus groves
    treated with 5 applications of 2.5 EC (two at 4.2, two at 1.1 and one
    at 4.2 kg a.i./ha) carbosulfan was not found ( <0.01 mg/l) in
    drainage tile or ditch water in or outside treated plots (Leppert,
    1983c). Carbofuran was found inside and outside the treated plots,
    initially higher in ditch water than drain tile water. A maximum of
    0.64 mg/l was found five days after the maximum application rate,
    following substantial rainfall. The pH of the water ranged from 6.5 to
    9.2. The maximum carbofuran level outside the treated plots was
    0.58 mg/l in the grove ditch, which water entered from the treated
    plot. <0.05 mg/l was found down-stream in the grove ditch water
    which drained into the county drain system. In general residues
    dissipation was related to time, application rate and rainfall.

    In storage

         Two reports were available on the storage stability of
    carbosulfan in soil and in various crops. In one study (Markle, 1980)
    the stability of field-incurred residues of carbosulfan and its
    metabolite carbofuran was investigated in crops stored up to one year
    at -18C. No losses of carbosulfan or carbofuran, green alfalfa
    containing 30 and 3.8 mg/kg or alfalfa hay containing 45 and 12 mg/kg.
    In sandy loam and clay loam soils stored at -18C, approximately
    50-60% of the carbosulfan was lost during one year. In clay loam the
    loss was accounted for by an equivalent increase in carbofuran. In
    sandy loam carbofuran increased by 100% but this did not account for a
    significant proportion of the loss. In silt loam degradation of
    carbosulfan was almost complete during the 3-hour fortification/
    extraction period in repeated attempts. The significant physical and
    chemical differences between the silt loam and the other two soils
    were a lower pH (4.8, 6 and 6.8) and higher cation exchange capacity
    (19.5, 11.8 and 12.9). It was found that leaching was inversely
    related to cation exchange capacity and that carbosulfan was
    significantly less stable at pH 5 than at pH 7 (see above). Since
    degradation has also been shown to be very rapid in dry soil (Capps,
    1981; see below), the fact that these samples were dried before
    fortification may partly explain the loss.

         In the second study untreated green alfalfa, cabbage, corn forage
    and potatoes were fortified with carbofuran and stored for periods up
    to 21 months at -18C (Burt, 1982). In green alfalfa carbosulfan
    decreased linearly by 40% in 21 months (20% in 12 months for
    comparison with the field-incurred residue). The loss was accounted
    for by an equivalent increase in carbofuran. In cabbage 50% of the
    carbosulfan was lost within 3 weeks, and the sum of carbosulfan and
    carbofuran decreased by 40% within this period, so most of the
    carbosulfan loss could not be accounted for. Carbofuran alone was
    shown to be stable for 12 months in cabbage at -18C. Losses in corn
    forage were approximately 20% in three months and 50% in 12 months.
    They were not linear and not fully accounted for by carbofuran
    increases since the combined carbofuran and carbosulfan residues
    decreased by approximately 10% and 30% in the 3- and 12-month periods.

         Carbosulfan was shown to be stable in ethyl acetate, ethanol and
    ethanol-acetone solutions. For example 99% was recovered from ethanol
    after one month. It was shown to be unstable under acidic conditions
    (pH3-5), but stable under neutral or alkaline conditions, over 90%
    being recovered after 9 days at pH 9. Under acidic conditions
    carbofuran was the major product.

    In processing

    Citrus.  Several studies showed that residues of carbosulfan and its
    carbamate metabolites are almost all in the peel (Table 15 FMC, 1984,
    1-10, VI-3 and VI-7). The same is largely true of phenolic residues in
    oranges (Table 15), and in grapefruit (FCM, 1984, I-9) where peel
    residues were >92% of the total. Except on day 0, when the 7-phenol
    was higher, the 3-hydroxy-7-phenol predominated in grapefruit whereas
    the 7-phenol was predominant at all intervals in oranges.

         A citrus-processing study was conducted on Marsh Grapefruit and
    Valencia oranges, field-treated four or five times with a total of
    approximately 11 kg a.i./ha with a 2.5 EC carbosulfan formulation.
    (FMC, 1984, I-2, 5, 18). Average residues of carbosulfan and total
    carbamates in whole fruit on the day of last application were:

                        Oranges             Grapefruit
                        unwashed  washed    unwashed  washed

    Carbosulfan         0.17      0.08      0.12      <0.05
    Total carbamates    0.73      0.82      0.58      0.44

         Average concentration factors for residues in the processed
    products are given in Table 16 where the highest concentration factor
    for carbamate residues is shown by the oil, followed in order by dried
    pulp and molasses. Concentration factors for total phenols increase in
    the order oil <dry pulp (11-14% moisture) <molasses, with no
    concentration in juice or finisher pulp (80-86% moisture).


        Table 15.  Average residues in peel, edible fruit and whole fruit - oranges1 (FMC, 1984, I-10; I-23)

                                                                                                                            

                                                                   Residue, mg/kg2,3
                       Days                                                                                                 
                       from                                                                                       %
                       last                                         3-Hydroxy-      3-Keto-        Total          Residue
    Sample             Application    Carbosulfan    Carbofuran     carbofuran      carbofuran     carbamates     in Peel
                                                                                                                            

    Edible Fruit          0            (0.01)           ND             ND              ND          (0.01)
                          7             ND              ND             ND              ND           ND
                         14             ND              ND            (0.01)           ND          (0.01)
                         28             ND              ND            (0.01)           ND          (0.01)

    Peel                  0             5.02            0.98           0.21            0.10         6.31          99.6
                          7             1.21            2.36           0.45            0.43         4.45          99.8
                         14             0.27            2.00           0.42            0.36         3.05          99.8
                         28             0.03            1.46           0.55            0.32         2.36          98.8

    Residues as           0             1.58            0.31           0.07           (0.03)        1.99
    Whole Fruit4          7             0.38            0.74           0.14            0.14         1.40
     (Mature)            14             0.08            0.63           0.14            0.11         0.96
                         28            (0.01)           0.46           0.18            0.10         0.75

                                                     3-Keto-        3-Hydroxy-                     Total
                                      7-Phenol       7-phenol       7-phenol                       phenols

    Edible Fruit          0             ND2             ND             ND                           ND
                          7             ND              ND             ND                           ND
                         14             ND              ND             ND                           ND
                         28             ND              ND             ND                           ND
                                                                                                                            

    Table 15.  (continued)

                                                                                                                            

                                                                   Residue, mg/kg2,3
                       Days                                                                                                 
                       from                                                                                       %
                       last                                         3-Hydroxy-      3-Keto-        Total          Residue
    Sample             Application    Carbosulfan    Carbofuran     carbofuran      carbofuran     carbamates     in Peel
                                                                                                                            

    Peel                  0             0.30            ND             ND                           0.30          100
                          7             0.30            0.14           0.08                         0.52          100
                         14             0.28            0.15           0.06                         0.49          100
                         28             0.23            0.18           0.08                         0.49          100

    Residues as           0             0.10            ND             ND                           0.09
    Whole Fruit           7             0.09           (0.04)          0.03                         0.16
      (Mature)           14             0.09            0.05          (0.02)                        0.15
                         28             0.08            0.06          (0.03)                        0.15
                                                                                                                            

    1  Two applications of 2.5EC at 1.65 kg a.i./ha, one at early post-bloom and the second 21 days later.
    2  ND = none detected (<0.01 mg/kg).
    3  Numbers in parenthesis are estimated levels at or above limit of detection and below limit of determination (0.05 mg/kg).
    4  Whole fruit residue calculated, assuming a 2.2:1 pulp:peel ratio.

    Table 16.  Average residue concentration factors for processed citrus products (FMC, 1984, I-2).

                                                                                                                            

                                                      Average Concentration Factors1
                                                                                                                            
    Processed                  Valencia Oranges                                        Marsh Grapefruit
    Product                                                                                                                 
                                            3-Hydroxy-   Total                                     3-Hydroxy-     Total
                   Carbosulfan Carbofuran   carbofuran   carbamates  Carbosulfan     Carbofuran    carbofuran     carbamates
                                                                                                                            

    Juice          NCF2        NCF          NCF          NCF         NCF             NCF           NCF            NCF
    Molasses       <IX         1.6X         1.3X         1.1X        NCF             1.7X          2.9X           2.0X
    Dried
      pulp         <IX         1.2X         5.5X         2.9X        <1X             1.1X          4.0X           2.6X
    Finisher       NCF         <1X          <1X          <1X         NCF             NCF           NCF            NCF
      pulp
    Oil            7.2X        15.2X        <1X          7.1X        20.2X           11.3X         <1X            7.0X
                                                                                                                            
                               3-keto-      3-hydroxy-   Total                       3-keto-       3-hydroxy-     Total
                   7-phenol    7-phenol     7-phenol     phenols     7-phenol        7-phenol      7-phenol       phenols
                                                                                                                            
    Juice          NCF         NCF          NCF          NCF         NCF             NCF           NCF            NCF

    Molasses       8.3X        16.5X        19.1X        16.7X       3.8X            5.3X          11.6X          8.6X

    Dry pulp       3.5X        7.5X         9.2X         7.9X        2.5X            4.3X          5.6X           4.7X

    Finisher
      pulp         NCF         NCF          0.07X        0.05X       0.25X           0.5X          0.09X          0.2X

    Oil            10.8X       4.3X         0.07X        2.6X        3.5X            2.0X          NCF            1.2X
                                                                                                                            

    1  Concentration factors based on change from unwashed fruit residues.
    2  NCF = no concentration factor could be calculated.
    
         Dibutylamine was shown to be concentrated only in dry pulp
    (2.1 and 2.4 times in grapefruit and oranges respectively).

    Apples.  Processed products from apples from trees sprayed with a
    2.2 kg a.i./ha 4EC dormant application followed by three 1.1 kg
    a.i./ha summer sprays were analysed for carbosulfan and its
    cholinesterase-inhibiting metabolites (Witkonton, 1983a) phenolic
    residues (Witkonton, 1983b) and DBA residues (Witkonton, 1983c;
    Wright, 1983). Samples were harvested on the day of last application.
    Concentration factors (Table 17) were 2-4 in wet pomace and 3-12 in
    dry pomace. Only 3-hydroxycarbofuran was concentrated, 1.8 times, in
    apple cider. Residues in both canned and frozen apple sauce were lower
    than in the whole apples from which they were processed.

    Photodecomposition

         The photodecomposition of carbosulfan has been studied in aqueous
    solutions and soils (Capps, 1981). In soil photolysis experiments,
    14-ring- and DBA-labelled carbosulfan were applied at 25 mg/kg to a
    thin layer of air-dried silt loam soil which was irradiated for
    8 days. Decomposition was extremely rapid and, except during the first
    10 minutes, there was no significant difference between irradiated
    samples and dark controls, indicating that irradiation was not the
    controlling factor. Within 10 minutes, ring-labelled carbofuran
    accounted for 86.4 and 77% of the recovered radioactivity in
    irradiated and control samples respectively. The other prominent
    residues in the irradiated sample after 10 minutes were carbosulfan
    sulphone 94.5%), the 7-phenol (2.6%) and carbosulfan (1.2%).
    Carbofuran was by far the main residue throughout the 8-day
    experiment. Dibutylamine (38.6%) was the predominant identified
    DBA-labelled residue at 10 minutes. After 8 days 53% was unidentified
    (9-10 compounds, none >12.6%), while DBA at 7.7% was still the
    predominant identified residue.

         Carbosulfan was much more persistent in soil at 70% field
    moisture than in dry soil, accounting for 76-98% of the recovered 14C
    from 3-48 hours after the application of DBA-labelled carbosulfan
    while again there was little difference between irradiated and control
    samples or surface and incorporated application.

         Ring- and DBA-labelled carbosulfan at a concentration of 5 mg/l
    in buffered and distilled water was irradiated (>300 nm sunlamp) at
    1500 w/cm2. In pH 7 buffer, the half-life of the ring-labelled
    compound was 1.3 days. After 8 days, carbosulfan and carbofuran
    accounted for 1.8% and 59.7% of the 14C respectively. The
    corresponding proportions in unirradiated control samples were 46.3%
    and 37.6%, indicating the marked effect of irradiation. The half-life
    of 14C-DBA-labelled carbosulfan in buffered solutions was similar and
    the main identified residue after 4 days was DBA. In unexposed
    controls, carbosulfan was still the main residue after 8 days.


        Table 17.  Carbosulfan and metabolite concentration factors for processed apple products

                                                                                                                                               

                                    Residues, mg/kg in whole apples; concentration factors for processed products
                                                                                                                                               
                                                                    Total
                                            3-OH-       3-keto-     carbamate                   3-keto-      3-OH-       Total
    Product        Carbosulfan  Carbofuran  Carbofuran  carbofuran  metabolites   7-phenol      7-phenol     7-phenol    phenolics   DBA
                                                                                                                                               

    whole apples
                   0.24 mg/kg   0.2 mg/kg               <0.02 mg/kg               0.07 mg/kg    <0.03 mg/kg  0.03 mg/kg             0.23 mg/kg

    wet pomace     3.1X         2X          3X          UDC1        2.2X          2.9X          UDC          2.3         2.8X       4.2X

    dry pomace     12.1X        12X         4.6X        UDC         10.5X         7.7           UDC          3.3         6.7X       12.4X

    apple cider    no conc.     0.2X        1.8X        UDC         0.6X          0.6X          UDC          no conc.    0.6X       UDC

    apple sauce
    frozen         no conc.     0.2X        0.2X        UDC         0.2X          0.6X          UDC          no conc.    0.4X       UDC

    canned         no conc.     0.2X        0.2X        UDC         0.5X          no conc.      UDC          no conc.    no conc.   UDC
                                                                                                                                               

    1  UDC - Concentration factor could not be determined because residues in whole apples or product were below the limit of
       determination.
    
         In distilled water the half-life of ring-labelled carbosulfan was
    4 days. Carbofuran was again the major product of the radioactivity at
    4 days while carbosulfan accounted for 53%. The half-life of DBA-
    labelled carbosulfan was eight days.

    METHODS OF RESIDUE ANALYSIS

         An analytical method has been described for the determination of
    carbosulfan and carbofuran residues in various crops, water and soil
    (Leppert et al., 1983). High-moisture crops were extracted with
    hexane and isopropanol; low-moisture crops and soil with 9:2 methanol:
    buffer; high-terpene-oil samples (e.g. citrus oils) by acetonitrile
    partition from hexane solution, and water with methylene chloride.
    Sample clean-up varied according to crop type and included gel
    permeation for high-vegetable-oil crops. Additional clean-up was
    typically by Florisil column chromatography with hexane: ethyl acetate
    eluants, which separate carbosulfan and carbofuran, and by charcoal-
    Attaclay-alumina oxide columns. Determination was by gas
    chromatography using an unspecified nitrogen-selective detector.

         The procedure was validated for various crops (e.g. alfalfa,
    rice, citrus, brassica, corn, potatoes, sugar beets), water and soil
    at levels down to 0.05 mg/kg for most crops, 0.25 mg/kg for corn and
    sugar beets, 0.3 and 0.5 mg/kg for green alfalfa and alfalfa hay
    respectively, and 0.005 mg/l for water. Average recoveries were
    >75% in all cases and >85% in most. No attempt was made to
    define the limit of determination, although a peak at the retention
    time of carbofuran which would correspond to 0.02 mg/kg was said to be
    the limiting factor. While organosoluble metabolites other than
    carbofuran would probably be extracted, conjugated residues would not
    be measurable without hydrolysis. The procedure was not tested for
    other metabolites.

         Recovery of dibutylamine-14C carbosulfan from green or dry
    (16% moisture) alfalfa has been shown to be >86% efficient with 2:1
    v/v methanol: water or 9:1 v/v methanol: phosphate buffer (Findlay,
    et al., 1983).

         For the determination of dibutylamine, green alfalfa (Wright,
    et al, 1982a) and dry alfalfa hay (Wright, II-7) were extracted
    with 2:1 methanol/water, then with dichloromethane after basification.
    Samples were derivatized with dansyl chloride, partitioned with hexane
    and cleaned up on a Florisil column. Determination was by 
    electron-capture GC. Recoveries (corrected for controls) were 75 3%
    (69-79%) for green alfalfa at 1 and 10 mg/kg and 73.9 5% (67-77%) for
    hay at 3 and 25 mg/kg. The lower fortification levels were at the
    limits of determination, while the limits of detection were 0.1 and
    0.02 mg/kg for hay and green alfalfa respectively.

         The only published method provided to the meeting was that of
    Leppert, et al. (1983). In the field residue trials a variety of
    analytical methods were used, most of which were similar to the above,
    modified for particular situations. Typically carbamates were
    extracted with hexane/acetone or methanol buffered at pH 8, cleaned up
    by dichloromethane (DCM) partition and Florisil and/or silica column
    chromatography, and determined by thermionic GC. Samples were usually
    hydrolyzed to release 3-hydroxycarbofuran which was partitioned into
    dichloromethane and cleaned up by further partition and column
    chromatography before ethoxylation for analysis.

         Phenolics were typically hydrolyzed with HC1, partitioned with
    dichloromethane, ethoxylated with ethanol under reflux, and
    partitioned with DCM under basic and acidic conditions before silica
    gel (Sep-Pak) clean-up and analysis by GCMS.

         Dibutylamine was typically extracted with 2:1 methanol/water,
    cleaned up by several acid and basic DCM extractions, derivatized with
    dansyl chloride, cleaned up on Florisil and analysed by 
    electron-capture GC.

         Similar approaches were used for the analysis of poultry
    products, except that carbosulfan and carbofuran were extracted with
    actenitrile, partitioned with hexane, and cleaned up on 
    Darco-Attaclay/alumina and Florisil columns. In some cases carbamates
    were partitioned with ethanol/ether/hexane, 1:2:1, cleaned up on 
    gel-permeation columns and determined by HPLC.

         Limits of determination varied. They were usually <0.05 mg/kg
    for each of the carbamates, but were 0.1 mg/kg in cereal grain stalks,
    pome fruit, and grass or clover hay; 0.3-0.5 mg/kg in green grass,
    clover or alfalfa and 2 mg/kg in alfalfa hay. The limit of
    determination for phenolics where known was also generally
    <0.05 mg/kg but was 0.1 mg/kg in stover. Limits of determination
    for DBA were <0.05 mg/kg in pome fruit, 0.1-0.2 mg/kg in cereal
    grain and stover, and 0.3-0.5 mg/kg in cereal grain stalks and citrus.

         In general the analytical methods used in the field trials, if
    made available to regulatory authorities, appear to be adequate for
    enforcement, assuming further metabolism studies do not reveal other
    metabolites which should be determined.

    NATIONAL TOLERANCES REPORTED TO THE MEETING

         No information was provided.

    APPRAISAL

         Carbosulfan is a broad-spectrum carbamate pesticide closely
    related to its major metabolite carbofuran, a pesticide in its own
    right.

         Substantial residue data were available but because sufficient
    information on nationally approved uses was not provided or was
    provided too late for consideration, especially for those countries
    where supervised trials were conducted, the meeting could not with any
    confidence estimate maximum residue levels which would reflect
    established good agricultural practice. The meeting reviewed the data
    sufficiently to permit estimation of maximum levels at a future
    meeting (for commodities on which data are adequate) when nationally
    approved use information (including pre-harvest intervals) and other
    required information becomes available. Because sufficient residue
    data and information on corresponding proposed agricultural practices
    were available, a temporary limit was estimated for citrus fruit.

         The fate of carbosulfan has been studied in animals, plants,
    soil, water and light, although the meeting did not consider available
    metabolic information on animals and plants to be adequate. Carbofuran
    is a major metabolite and degradation product of carbosulfan, and
    available information indicates that the fate of carbosulfan in these
    matrices is to a large extent the same as that of carbofuran. The
    major difference in plants is the additional presence of carbosulfan
    and (at relatively low levels) various carbosulfan carbamate
    metabolites retaining the S-dibutylamine group (e.g. carbosulfan
    sulphone, 3-ketocarbosulfan or hydroxy- analogues of these) as well as
    dibutylamine which occurs as a major portion of the total residue in
    both plants and animals.

         Carbosulfan dissipation appears to be similar from WP or EC
    applications. The compound is unstable under acidic conditions but
    relatively stable under basic conditions. From foliar applications it
    is absorbed and metabolized, although translocation, at least in corn
    and cotton plants, is towards the extremities. Carbosulfan is rapidly
    translocated and metabolized from stem injections.

         From soil applications to rice, soybeans and corn there appears
    to be minimal uptake of carbosulfan per se, although its principal
    metabolites carbofuran, 3-hydroxycarbofuran and dibutylamine (DBA) are
    readily absorbed and translocated. Although no plant metabolism
    studies were provided for root vegetables, the predominance of
    carbosulfan per se, apparently after foliar or soil application,
    suggests that translocation and metabolism may differ between root
    vegetables and other plants. Metabolism studies on root crops are
    needed. Citrus metabolism studies are also desirable as the fate of
    residues in citrus may differ from that in other plants investigated.

         In plants carbosulfan is typically the predominant residue at or
    near the last day of application, while thereafter carbofuran and/or
    3-hydroxy-carbofuran tend to be the predominant carbamate residues in
    many commodities, the latter primarily as a conjugate. Conjugation
    increases with time. There are exceptions as noted above. For example,
    carbosulfan was the main residue in clover stems and apples even after
    28 days, as it was in some root vegetables at harvest after foliar or
    in-furrow granular applications.

         3-ketocarbofuran is generally less than 10% of the total
    carbamate residue, ranging from undetectable in apples to 20% in
    citrus. Depending upon commodity and conditions, phenolics may
    typically account for 10-30% of the total residue and DBA has been
    found up to 60% in plant metabolism studies.

         As in the case of plants, the metabolism picture for animals is
    not complete as residues detected in ruminant studies were not
    identified. In general, available information suggests that the major
    qualitative difference between plant and animal tissue, milk or egg
    residues is the absence of carbosulfan or its derivatives retaining
    the -S-dibutylamine group in the animal products, whereas they occur
    in plants, although (except for carbosulfan itself) at relatively low
    levels. However, these compounds have been identified in rat urine.
    Low levels (<3% of the residue) of desmethyl carbofuran and
    N-hydroxymethyl-3-ketocarbofuran have also been reported in plants,
    but not in animal tissues or urine.

         A goat study with labelled carbosulfan showed rapid elimination,
    primarily in the urine, with residues in milk becoming constant after
    about 3 days and containing approximately 2% of the administered
    radioactivity. Maximum 14C residues decreased in the order kidney
    > liver > milk > other tissues, while fat residues increased during
    the withdrawal period. Residues in blood increased throughout the test
    period. Residues were not identified, leaving an incomplete metabolism
    picture.

         In poultry residues reached a plateau at 7-10 days and were 
    dose-dependent. The 3-hydroxy-7-phenol was predominant in liver and
    3-hydroxy-carbofuran in thigh tissues. No carbosulfan or carbofuran
    were found in either. From DBA-labelled carbosulfan, DBA was the major
    egg residue. Most of the residue was unidentified, although most of
    the radioactivity was shown to be incorporated into individual fatty
    acids. Egg residues from the ring-labelled carbosulfan study were not
    identified.

         Conventional poultry feeding studies and metabolism studies
    suggest that residues of carbosulfan, carbofuran, 3-hydroxycarbofuran
    and 3-ketocarbofuran would all be below their limits of detection
    after the consumption of major feed items (corn and sorghum)
    containing residues at the highest expected levels.

         No conventional feeding studies have been provided for cows.
    Until MRLs can be estimated which reflect nationally approved
    agricultural practice, and the plant and animal metabolism picture is
    more complete, no MRLs can be estimated for animal products.

         In soils carbosulfan is only of low mobility, although its major
    carbamate degradation product is substantially more mobile.
    Dibutylamine is a major non-carbamate product in soil.

         In water carbofuran is the major product under acidic conditions
    and the 7-phenol under basic conditions.

         The stability of carbosulfan in crops and soil under cold storage
    varies considerably depending on the commodity and whether the soil is
    dry or moist, stability being much higher in moist soils than dry. In
    the commodities tested, stability ranged from no loss in citrus after
    one year to 50% loss in brassica after three weeks. In some cases the
    loss is accounted for by an equivalent increase in the carbofuran
    content. Brassica was an exception where the carbofuran increase did
    not account for the carbosulfan loss. In general, the validity of
    residue data for samples stored for more than a few months (or less in
    the case of brassica) becomes increasingly doubtful as the storage
    time increases. For many of the residue trials there was no
    information on storage conditions or intervals. This is of particular
    concern for brassica for which this information should be provided.
    There is some evidence that field-incurred residues may be more stable
    than residue components added in fortification experiments. Further
    information is desirable.

         In processing, total carbamate residues in citrus were reduced
    somewhat by washing and carbosulfan itself by as much as 50% with most
    of the citrus residue being on the peel as it is for apples.
    Significant carbamate concentration occurs in citrus processing
    products, especially in the oil and dry pulp. Carbamate residues also
    concentrate in apple processing products, primarily in pomace and less
    in cider.

         No information is available on possible residue concentration in
    grain milling products and this is desirable. All of these will be of
    special significance for the eventual estimation of possible residue
    levels in animal products.

         Light has little effect on the degradation of carbosulfan in
    soil, but it affects degradation in water. In both cases carbofuran
    and DBA are the major products.

         Analytical methods suitable for enforcement have been developed.
    For carbamates extraction is followed by solvent partition, column
    chromatographic clean-up and GLC with thermionic detection. For the
    determination of 3-hydroxycarbofuran, samples are hydrolyzed and
    ethylated before analysis. Methods have also been developed for the
    determination of phenolic residues and dibutylamine.

    RECOMMENDATIONS

         The meeting examined residue data from supervised trials
    reflecting, in part, proposed (and possibly current) good agricultural
    practice on a number of commodities, and was able to estimate a
    maximum residue level for citrus fruit which may occur when
    carbosulfan is used as in the trials and when the reported interval
    between last application and harvest is observed. The level refers to
    the sum of carbosulfan, carbofuran, 3-hydroxycarbofuran and
    3-ketocarbofuran.

                                                                   

                                  Pre-harvest interval on which
                   MRL            recommendation is based
    Commodity      (mg/kg)1/      (days)
                                                                   

    citrus fruit      2                        28
                                                                   

    1/    MRL is temporary irrespective of the status of the ADI until
          required information is provided and found by the JMPR to be
          satisfactory.

    FURTHER WORK OR INFORMATION

    Required (1987)

    1.   Information on nationally registered, approved, or recommended
         good agricultural practices. This should include approved
         formulations, application rates (a.i./ha) number and type of
         applications and intervals between them, interval from last
         application to harvest and any other information for the meeting
         to determine whether residue field trials data reflect approved
         uses. Emphasis should be given to uses in countries where the
         trials were conducted or those in close proximity.

    2.   Metabolism studies on a root crop after uptake from both foliar
         and soil treatment.

    3.   Identification of residues found in ruminants tissues and milk.

    4.   A conventional ruminant feeding study.

    5.   Identification of residues found in eggs from ring-labelled
         carbosulfan metabolism studies.

    6.   Further information on the storage conditions and time for
         brassica samples. Additional field trials data may be required
         with a short harvest-to-analysis interval, depending on the
         information provided.

    Desirable

    1.   A citrus metabolism study.

    2.   Grain processing studies.

    3.   Further information on storage conditions and intervals for pome
         fruit.
    4.   Additional storage stability data, especially with field-incurred
         residues.

    5.   In addition to other carbosulfan metabolites determined, analysis
         of poultry tissues and eggs for 3-hydroxy-N-hydroxycarbofuran,
         which has been found in metabolism studies. If found in cow
         tissues at significant levels during metabolism studies, those
         tissues and milk should also be analysed for this compound in
         conventional feeding studies.

    6.   Information on poultry, egg and tissue residues of dibutylamine
         from studies in which it was fed at 10 ppm in the diet.

    REFERENCES

    Bixler, T.A., Metabolism of Ring-14C and Dibutylamine 14C Carbosulfan
    1982      in Alfalfa. Unpublished FMC Report M-4846, May 11, 1982.

    Butt, J.E., Carbosulfan Storage Stability Study In/On Various Crops.
    1982      Unpublished FMC Report M-4851.

    Capps, T.M., Metabolism of Ring-14C FMC 35001 In Rice. Unpublished
    1980a     FMC Report M-4492, September 17, 1980.

    Capps, T.M., Uptake of FMC 35001 Into Rice Plants - Whole Plant Auto-
    1980b     radiography. Unpublished FMC Report M-4624, December 5,
              1980.

    Capps, T.M., Metabolism of Dibutylamine-14C FMC 35001 In Rice.
    1980c     Unpublished FMC Report M-4625, December 8, 1980.

    Capps, T.M., Uptake of Soil - Aged FMC 35001 Residues into Outdoor
    1980d     Rotational Crops - 9 Month Interval. Unpublished FMC Report
              M-4619, November 25, 1980.

    Capps, T.M., Photodecomposition of FMC 35001. Unpublished FMC Report
    1981      M-4648, January 26, 1981.

    El-Nagger, S.F. and Reynolds, J.L., Hydrolysis of Carbofuran.
    1982      Unpublished FMC Report M-4844, May 6, 1982.

    Findlay, C.R. and Witkonton, S., Extractability of Plant Incorporated
    1983      Residue From 14-Advantage Treated Alfalfa. Unpublished FMC
              Report P-0750, November 2, 1983.

    Froelich, L.W., Nitrification Study With Carbosulfan. Unpublished FMC
    1982      Report M-4814.

    Froelich, L.W. and El-Nagger, S.F., Substrate Degradation Study With
    1982      Carbosulfan. Unpublished FMC Report M-4810, March 11, 1982.

    Huhtanen, Kurt, Goat Feeding Study With 14-FMC-35001 2,3 Dihydro-2,
    1979      2-Dimethyl-7-Benzofuranyl (Di-n-Butylaminosulfenyl) Methyl
              Carbamate. Unpublished FMC Report (Cannon Report 9E-4846),
              May 15, 1979.

    Kinne, L.P., The Effect of Microorganisms on Carbosulfan. Unpublished
    1982      FMC Report M-4812. March 12, 1982.

    Leppert, B.C., Dissipation of FMC 35001 Residues in Soils From Alfalfa
    1981a     Fields Following Multiple Applications. Unpublished FMC
              Report RAN-0002, March 6, 1981.

    Leppert, B.C., Determination of FMC 35001 and Carbofuran Residues in
    1981b     Soil from Treated Citrus Groves. Unpublished FMC Report RAN-
              0024, March 31, 1981.

    Leppert, B.C., Determination of Carbosulfan and Carbofuran Residues in
    1981c     Soil From Treated Citrus Groves. Unpublished FMC Report RAN-
              0034, December 8, 1981.

    Leppert, B.C., Determination of Dislodgable Carbosulfan and Its
    1982      Cholinesterase Inhibiting Metabolite Residues In An Apple
              Reentry Study. Unpublished FMC Report RAN-0066, November 19,
              1982.

    Leppert, B.C., Determination of Carbosulfan And Its Cholinesterase
    1983a     Inhibiting Metabolites in Eggs From a Poultry And Egg
              Residue Study With Carbosulfan Technical and Dibutylamine
              Technical In White Leghorn Chickens. Unpublished FMC Report
              RAN-0091, June-July, 1983.

    Leppert, B.C., Determination of Carbosulfan and Carbofuran Residues in
    1983b     Soil From a Michigan Apple Orchard. Unpublished FMC Report
              RAN-0074, February 3, 1983.

    Leppert, B.C., Final Report - Completion of Carbosulfan Surface and
    1983c     Ground Water Project. Unpublished FMC Report RAN-0076, March
              2, 1983.

    Leppert, B.C., Markle, J.C., Helt, R.C., and Fujie, G.H.,
    1983      Determination of Carbosulfan and Carbofuran Residues in
              Plants, Soil and Water by Gas Chromatography. J. Agric. Food
              Chem., Vol. 31, No. 2. P. 220-223, 1983.

    Markle, J.C., Cold Storage Stability of FMC 35001 Residues in/on
    1980      Various Crops and Soils. Unpublished FMC Report RAN-0016.

    Markle, J.C., Comparative Soil Degradation of Ring-14C FMC 35001
    1981a     Under Aerobic and Anaerobic Conditions. Unpublished FMC
              Report RAN-0031, September 21, 1981.

    Markle, J.C., Comparative Soil Degradation of Dibutylamine-14C FMC
    1981b     35001 Under Aerobic and Anaerobic Conditions. Unpublished
              FMC Report RAN-0033, December 9, 1981.

    Markle, J.C., Identification of 14C-Residues In Tissues And Eggs From
    1982a     Poultry Administered [Ring-14C] Carbosulfan. Unpublished
              FMC Report RAN-0052, June 1, 1982.

    Markle, J.C., Identification of 14C-Residues In Tissues And Eggs From
    1982b     Poultry Administered [Dibutylamino-14C] Carbosulfan.
              Unpublished FMC Report RAN-0052, June 1, 1982.

    Nishioka, Takaaki; Umetsu, Noriharu; and Fukuto, T. Roy, Side-Chain
              Group Metabolism of Dibutylaminosulfenyl Derivative of
              Carbofuran In Cotton Plant. Report for Pesticide
              Biochemistry and Physiology, provided by FMC, undated.

    Reynolds, J.L., Leaching of Carbosulfan and its Aged Soil Residues in
    1982      Various Soil Types. Unpublished FMC Report M-4826, March 29,
              1982.

    Robinson, R.A., Soil Adsorption/Desorption Characteristics of FMC
    1980      35001. Un-1980   published FMC Report M-4629, December 29,
              1980.

    Robinson, R.A., Soil Mobility of FMC 35001. Unpublished FMC Report
    1981      M-4647, January 22, 1981.

    Rogers, L., Stability and Persistence of Dibutylnitrosamine In Soil.
    1982      Unpublished FMC Report M-4835, April 16, 1982.

    Tilka, M.A., Determination of Carbosulfan and Its Cholinesterase-
    1983      Inhibiting Metabolites in Tissues From a Poultry and Egg
              Residue Study With Carbosulfan Technical in White Leghorn
              Chickens. Unpublished FMC Report RAN-0093, June-July 1983.

    Umetsu, Noriharu; Fahmy, Mohamed A.H.; and Fukuto, T. Roy, Metabolism
    1979      of 2,3-Dihydro-2,2-dimethyl-7-benzofuranyl(di-n-
              butylaminosulfenyl) (methyl) carbamate and 2,3-Dihydro-2,2-
              dimethyl-7-benzofuranyl-(morpholinosulfenyl) methylcarbamate
              In Cotton and Corn Plants. Pesticide Biochemistry and
              Physiology 10, 104-119 (1979).

    Wilkes, Laurie C.; Gustafson, David E.; Adams, Linda; and Wargo,
    1981      Joseph P., Jr., 14C-FMC 35001 Poultry Metabolism Study.
              Unpublished FMC Research Report ADC Project No. 592, January
              14, 1981.

    Table 3 References.  Table 3 references refer to volume references 
    1984      in FMC data 1984 package provided to the JMPR. report 
              numbers and dates are cross-referenced below:

    Volume -            FMC
    Reference           Report No.          Date
                                                      

    I     1               M-4650            02/02/81
          2                -4663            02/27/81
          3                -4847            01/25/82
          4                -4802            02/22/82
          5                -4824            03/29/82
          6                -4827            04/05/82
          7                -4834            04/13/82
          8                -4840            04/26/82
          9               P-0541            11/18/82
          10               -0642            05/18/83
          11               -0654            06/13/83
          12               -0663            07/12/83
          13               -0664            07/12/83
          14               -0747            11/02/83
          15               -0748            11/02/83
          16               -0749            11/02/83
          17            RAN-0020            02/13/81
          18               -0021            02/20/81
          19               -0028            06/11/81
          20               -0040            02/24/82
          21               -0044            03/26/82
          22               -0077            03/10/83
          23               -0080            03/31/83
          24                -008            04/15/83
    II    1               M-4709            06/16/81
          2                -4774            12/10/81
          3                -4846            05/11/82
          4               P-0488            09/19/82
          8              PC-0002            08/27/82
          9                -0003            08/27/82
          12            RAN-0019            02/13/81
          13               -0030            09/11/81
          14               -0081            04/08/83
          15               -0103            10/04/83
    III   1               P-0594            02/25/83
          2                -0601            04/13/83
          6                -0628            04/15/83
          11               -0623            05/03/83
          12              P-0624            04/29/83
          13             PC-0011            10/03/83

    Volume -          FMC
    Reference         Report No.            Date
                                                      

          14              M-4855            05/28/82
          15              M-4870            08/30/82
          16              P-0521            10/15/82
          17             PC-0005            09/20/82
          18              M-4492            09/17/80
          19              M-4624            12/05/80
          20              M-4625            12/08/80
          21            RAN-0100            09/13/83
    IIIa- 22              P-0586            02/04/83
          23              P-0671            07/25/83
          24               -0738            10/27/83
          25               -0760            11/16/83
          26             PC-0006            01/17/83
          27               -0013            07/25/83
          28            RAN-0053            06/10/82
          29               -0075            02/08/83
          30               -0085            05/31/83
          32               -0112            11/11/83
    V-    1               P-0566            01/10/83
          2                -0593            02/25/83
          3                -0690            08/23/83
          4              PC-0007            01/26/83
          5             RAN-0094            08/25/83
          6                -0109            11/08/83
    VI-   1         FCC41/821052            01/24/83
          2             27/82771            01/25/83
          3            40A/82583            05/18/83
          4          24/1/821053            01/26/83
          5     24/28/42/82/1050            02/25/83
          6            17/821049            01/25/83
          7           40/8/82584            05/18/83
    VII-  1                   17            04/15/83
          2                 none            04/15/80
          3                -73/1            1978
          4                 none            09/10/79
                                            11/14/80
          5               FCC 26            11/12/80
    VIII- 1                 none            04/82
          2                 none            04/82
          3               FCC 39            1981
          4                 none            04/83
          5                 none            1981
          9                 none            09/82



    See Also:
       Toxicological Abbreviations
       Carbosulfan (JMPR Evaluations 2003 Part II Toxicological)
       Carbosulfan (Pesticide residues in food: 1984 evaluations)
       Carbosulfan (Pesticide residues in food: 1986 evaluations Part II Toxicology)