Sponsored jointly by FAO and WHO


    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



         Date for the estimation of an acceptable daily intake for
    bitertanol were evaluated by the 1983 Joint Meeting which estimated a
    temporary acceptable daily intake. This evaluation considers residues
    in food and gives details of the identity of the compound.

    Chemical name:           all-rac-1-(biphenyl-4-yloxy)-3,3-

    Registry number          [55179-31-2]

    Synonyms:                Baycor, Sibutol

    Structural formula:                                         KWG 0599


    Empirical formula:       C20H23N3O2

    Molecular weight:        337.4



         Bitertanol is a broad-spectrum fungicide said to be effective for
    the control of scab and Monilinia fruit diseases, banana and peanut
    leaf spot diseases, and rusts and mildews on a variety of crops. It is
    available as a wettable powder, emulsifiable concentrate and
    suspension concentrate, all applied by spraying. It is also used as a
    seed treatment for cereals. Only the wettable powder is recommended
    for pome fruit owing to possible foliage or fruit injury by the EC

         Bitertanol is said to be registered and marketed in over 20
    countries in Europe, Africa and South America and registration is
    being sought in additional countries. Recommendations by geographical
    areas are listed in Table 1.


         Residue field trials have been conducted on a variety of crops,
    primarily fruits and vegetables. Data provided to the JMPR are
    summarized in Table 2.

    Pome Fruit

         Residues trials in apples have been conducted in four countries,
    although according to Table 1 bitertanol is currently approved for use
    in only one of the four. The trial in this country reflects European
    uses. Where reported, controls were <0.01 mg/kg. With maximum
    residues of 1.0 mg/kg at the recommended 14-day interval, these data
    and the supporting data from other countries indicate that a 2 mg/kg
    limit would be required with a 14-day pre-harvest interval. Additional
    data are desirable from countries with approved uses.


         Trials on cucumbers (under glass) were available from one country
    with WP application at approximately the approved rate and EC at twice
    the approved rate. Maximum residues were 0.41 mg/kg at the normal
    harvest interval. Residues from the two EC applications were similar
    to those from six with the WP at similar intervals. These limited data
    indicate a possible need for a 0.5 mg/kg limit at a 3-day pre-harvest
    interval, but are not sufficient to support a limit.


         In trials in one country reflecting approved application rates
    (but excessive numbers of applications) no residues were detected
    (<0.1 mg/kg) 9-14 days after the last application. Analyses were
    apparently on shelled nuts. Data are not sufficient to support a


         Data were available from trials in three countries, but approved
    use information was available from only one of these. From the country
    with approved uses residues in dry bean pods at 16 days (28-day safety
    interval required) were 0.1 - 0.18 mg/kg at the normal application
    rate. This compares with 0.1 mg/kg in untreated controls. Similar
    application rates in South America resulted in <0.05 mg/kg residues
    (3 samples) at 26-43 days post-treatment, but it is not clear whether
    the beans were shelled or in pod. Data are insufficient to support a

        Table 1.  Use Pattern - spray treatment


    Region and                                     Number of            Safety interval,
    Commodity                   g a.i./ha          treatments           days


    Pome fruit 1, 2             187 - 375          6 - 12               14 - 42

    Stone fruit                 375 - 562          2 - 3                *

    Snake gourd )
    (Cucumber   ) under
    Peppers     ) glass         9003               2 - 6                3
    Melons      )

    South Africa

    Peanuts                     195 - 240          2 - 4                as dry feed 42

    Stone fruit                 140 - 240          2 - 3                28

    Beans                       126 - 250**        2                    (as dry feed 42)


    Bananas                     125 - 150          26

    South America

    Bananas                     125                18 - 26

    *  Not later than at the end of flowering stage; following this application no residues are 
    ** aerial application
    1  Registration (pre-harvest WP on apples) at 0.05 - 1.0% and a 28-day PHI is under way in 
    2  Netherlands - 25 WP at 50-80 g a.i./100 1 and 300EC at 22.5 g/l. Both 14-day pre-harvest 
    3  300 EC in The Netherlands.

    Seed treatment - Federal Republic of Germany
    Wheat            75 g a.i./100 kg seed
    Rye              56 g a.i./100 kg seed
    Oat              56 g a.i./100 kg seed

        Table 2.  Bitertanol residues in crops resulting from supervised trials


                           Dose a i.              No. of                        Days after
    Crops                  (Formulation)          Applications    Country       last                Residue (mg/kg)            Report
                                                                  (year)        Application   Range              Average       No.

    Pome fruit                                                                                                                 Bayer
    Apples                 187 - 375 g/ha         10-12           FRG           14            0.13 - 1.8         0.65 (6) 1    10303/79
                           (25% WP)                               (1979-1982)   21            0.12 - 1.0         0.43 (6)      10305/79

                           1-4 oz/100 gal.        6-14            USA           0             0.53 - 2.54        1.62 (5)      64382+83
                           (50% WP)                               (1979)        14            0.24 - 1.5         0.9 (5)
                                                                                21            0.18 - 1.2         0.8 (4)
                                                                                28            0.27 - 0.91        0.6 (4)

                           1-2 oz/100 gal.        5-8             Canada        66-67         0.06 - 0.10        0.07 (4)      Mobay
                           (50% WP)                               (1983)        74-92         < 0.01 - 0.04      0.02 (12)     68282-86

                           0.8 g/tree             4               Finland                                                      Siltanen
                                                                  (1979)        32            0.2 (1)                          and Makinen
                                                                  (1980=        49            0.1                              1980
                                                  5               (1981)        67            0.04                             Siltanen
                                                  6                             35            0.1                              and Makinen
                                                  8                             24            0.4                              1981

    Cucumbers              875 - 1200 g/ha        2(EC)           NL            0- 1          0.4 - 0.7          0.54 (4)      Bayer
    (Snake gourds,         (200 g/1 EC or         6(WP)           (1979-1980)   3- 4          0.25 - 0.41        0.34 (3)      10326/79
    under glass)           50% WP)                                              7-10          0.06 - 0.25        0.15 (5)      10314-15/80


    Table 2 (continued)


                           Dose a i.              No. of                        Days after
    Crops                  (Formulation)          Applications    Country       last                Residue (mg/kg)            Report
                                                                  (year)        Application   Range              Average       No.

    Peanuts                250 - 300 g/ha         4-5             S.Africa      9-14          < 0.1              < 0.1 (3)     Bayer
    (Shelled?)             (300 g/L EC or                         (1979-1983)                                                  10301/77
                           25% WP)                                                                                             10313/78

    Beans                  225 - 250 g/ha         4               Costa         26            0.05               0.05 (1)      Bayer
    (mature, dry)          (300 EC)                               Rica          37            0.05               0.05 (1)      10332-33/80
                                                                  Columbia      43            0.05               0.05 (1)      10342/81

    Beans                  125 g a.i./ha                          S. Africa                                                    S. Africa
    (dry)                  (300 EC)                               (not avail.)                                                 submission
    whole plt.                                    1                             1             23 : 30
                                                                                4             2.5 : 3.4
                                                                                8             3.7 : 3.8
                                                                                16            0.36 : 0.3

                           250 g a.i./ha                                        1             43 : 39.4
                           (300 EC;                                             4             6 : 6.8
                           double rate)                                         8             4.5 : 5.0
                                                                                16            0.3 : 0.32

    pods                   125 g a.i. /ha         1                             11 sic?       2.7 : 2.4
                           (300 EC)                                             4             0.13: 9.19
                                                                                8             0.15: 0.13
                                                                                16            0.18: 0.10

    Table 2 (continued)


                           Dose a i.              No. of                        Days after
    Crops                  (Formulation)          Applications    Country       last                Residue (mg/kg)            Report
                                                                  (year)        Application   Range              Average       No.

                           250 g a.i./ha                                        11?           3.2 : 2.9
                           (300 EC;                                             4             0.16: 0.1
                           double rate)                                         8             0.4 : 0.4
                                                                                16            0.23: 0.21

                                                                                              A       B
    Stone fruit                                                   A
    Nectarines             100- 100 g/ha          4               S.Africa      0             0.53 - 1.5                       SABS
                           (300 EC)                               (1982)        3             0.47 - 0.68 (1)*   311/88419
                           data:                                                10            0.21 - 0.54 (1)    W 212
                           A = 0.125% a.i.                                      14            0.18 - 0.51
                           B = 0.25% a.i.                                       24            0.18 - 0.37 (1)

    Peaches                100 - 200 g/ha         3               S. Africa     0             0.6 - 1.8 (1)*                   SABS
                           (300 EC)                               (1982-1983)   5             0.4 - 1.2 (1)*                   311/88421/
                           data:                                                11            0.3 - - (1)*                     W214
                           A = 0.125% a.i.                                      19            0.2 - 0.5 (1)*
                           B = 0.25% a.i.                                       26            < 0.1 - - (1)*

        ripe               375 g/ha               3               France        0             1.7
                           (25& WP)                               (1979)        7             1.2
                                                                                14            1.3
                                                                                21            0.91

                           300 & 400 g/ha         3               Italy         0             0.8 - 1.2(1)*      (3.5cm fruit) Bayer
                           (300 EC)                               (1981)        7             0.3 - 0.4(1)*                    10346-47/81
                                                                                14            0.2 - 0.2(1)*
                                                                                20            0.11- 0.13(1)*     (5-7cmfruit)


    Table 2 (continued)


                           Dose a i.              No. of                        Days after
    Crops                  (Formulation)          Applications    Country       last                Residue (mg/kg)            Report
                                                                  (year)        Application   Range              Average       No.

    Plums                  250 - 370 g/ha         1               S. Africa     0             0.7 - 0.8(1)*
                           (300 EC)                               (1982)        3             0.8 - 0.8(1)*
                           data:                                                9             0.6 - 0.5(1)*
                           A = 0.025% a.i.                                      16            0.5 - 0.6(1)*
                           B = 0.0375% a.i.

    Bananas                120 - 300 g/ha         6 - 26          Costa Rica                                                   Bayer
    unbagged               (EC 200-300;                           Columbia      2             0.015              0.015(1)      10309-11/78
    pulp                   WP 25%)
                                                                  Taiwan        4             ND                 ND (1)        10320-21/80
                                                                  Kamerun       8             0.014-0.019        0.017(2)      10330-31/80
                                                                  (1978-1980)   23            < 0.1              < 0.1 (1)     10350-80
                                                                                40            ND                 ND (1)        10344-45/81
                                                                                78            ND                 ND (1)        10366/81

       peel                                                                     2             0.14               0.14(1)
                                                                                4             ND                 ND (1)
                                                                                8             0.12 - 0.15        0.14(2)
                                                                                23            0.025              0.025(1)
                                                                                40            ND                 ND (1)
                                                                                78            ND                 ND (1)

       total (calculated)                                         2             0.06          0.06(1)
                                                                                4             ND                 ND (1)
                                                                                8             0.047-0.055        0.051 (2)
                                                                                23            < 0.01             < 0.01 (1)
                                                                                40            ND                 ND (1)
                                                                                78            ND                 ND (1)


    Table 2 (continued)


                           Dose a i.              No. of                        Days after
    Crops                  (Formulation)          Applications    Country       last                Residue (mg/kg)            Report
                                                                  (year)        Application   Range              Average       No.

    bagged                                                                      0             ND                 ND (2)
       pulp                                                                     2             ND                 ND (1)
                                                                                6             ND                 ND (1)
                                                                                8             < 0.01             < 0.01 (2)
                                                                                11            ND                 ND (2)
                                                                                12            ND                 ND (1)

      peel                                                                      0             ND                 ND (2)
                                                                                2             0.019              0.019 (1)
                                                                                6             0.1                0.1 (1)
                                                                                11            ND                 ND (2)
                                                                                12            ND                 ND (1)

    Total (calculated)                                            0             ND
                                                                                2             < 0.01
                                                                                6             < 0.01
                                                                                8             < 0.01-0.015
                                                                                11            ND
                                                                                12            ND

    Bananas, green         125 - 300 g/ha         9 - 12          Honduras      0/3                                            Mobay
    unbagged,              (300 EC) or                            Costa                                                        68896-900
     unwashed              25 or 50% WP)                          Rica -                                                       80469-473
     pulp                                                         (1980-1982                  0.03-0.13          0.07(6)
     peel                                                                                     0.10-0.76          0.39(6)
     total                                                                                    0.06-0.33          0.19(6)

    unbagged, washed pulp                                                       0.03-0.17     0.09(5)
     peel                                                                                     0.09-0.73          0.37(5)
     total                                                                                    0.05-0.36          0.19(5)


    Table 2 (continued)


                           Dose a i.              No. of                        Days after
    Crops                  (Formulation)          Applications    Country       last                Residue (mg/kg)            Report
                                                                  (year)        Application   Range              Average       No.

    bagged, unwashed
     pulp                                                                                     < 0.01-0.01        < 0.01(4)
     peel                                                                                     < 0.01-0.05        0.03(4)
     total                                                                                    < 0.01-0.03        0.02(4)

    bagged, washed
     pulp                                                                                     < 0.01-0.02        0.01(5)
     peel                                                                                     0.03-0.15          0.06(5)
     total                                                                                    0.02-0.06          0.03(5)

    Bananas, ripe
    unbagged, unwashed
     pulp                                                                                     < 0.01-0.08        0.05(3)
     peel                                                                                     0.03-0.32          0.19(3)
     total                                                                                    0.01-0.17          0.10(3)

    Bananas, ripe
     unbagged, unwashed pulp                                                                  0.02-0.14          0.09(3)
     peel                                                                                     0.05-0.51          0.34(3)
     total                                                                                    0.03-0.28          0.18(3)

    Bananas, ripe
     pulp                                                                                     < 0.01-0.01        < 0.01(3)
     peel                                                                                     < 0.01-0.12        0.05(3)
     total                                                                                    < 0.01-0.05        0.02(3)


    Table 2 (continued)

                           Dose a i.              No. of                        Days after
    Crops                  (Formulation)          Applications    Country       last                Residue (mg/kg)            Report
                                                                  (year)        Application   Range              Average       No.
    bagged, washed
     pulp                                                                                     < 0.01-0.02        0.02(3)
     peel                                                                                     0.03-0.08          0.05(3)
     total                                                                                    0.01-0.04          0.03(3)

    Oats, Green forage     56 g/100 kg seed       1               FRG           94/97         < 0.05             < 0.05(2)     Bayer
     Grain                 (375 FS)                               (1983)        140-141       < 0.05             < 0.05(2)     10212+13/83
     Straw                                                                      140/I41       < 0.05             < 0.05(2)

    Rye, Green Forage      56 ml/100 kg seed      1               FRG           220/224       < 0.05             < 0.05(2)     10210+11/83
     Grain                 (375 FS)                               (1983)        291/295       < 0.05             < 0.05(2)
     Straw                                                                      291/295       < 0.05             < 0.05(2)

    Wheat, Green Forage    75 ml (g)/100 kg seed  1               FRG           56-77         < 0.1              < 0.1 (7)     10341+43/80
     Ears                                                         (1980-1982)   73-90         < 0.05-0.1         < 0.05-0.1(5) 10370+71/80
     Grain q               (375 FS)                                             130-154       < 0.05-0.1         < 0.05-0.1(5)
     Straw                                                                      87-154        < 0.05-0.1         < 0.05-0.1(7)

    Oats, Green Forage     200g product/100       1               FRG           63-86         < 0.1              < 0.1 (1)     10366+67/82
     Ears                  kg seed (0.132                         (1982)        75-86         < 0.1              < 0.1 (2)
     Grain q               kg a.i./ha)                                          131-139       < 0.05             < 0.05(2)
     Straw                 (37.5% DS)                                           131-139       < 0.05             < 0.05(2)

    Rye Green Forage       0.08-0.11 kg           1               FRG           219-254       < 0.1              < 0.1 (7)     10363-65/82
     Ears                  a.i./ha(150 g                          (1981-1982)   228-254       < 0.1              < 0.1 (4)     10372-82
     Grain                 production/100 kg -                                  291-308       < 0.05             < 0.05(4)
     Straw                 seed) (37.5 or                                       291-308       < 0.05             < 0.05 (4)
                           3.75 DS)


    1  Number in parenthesis = number of samples
    *  One sample per dose level (mean of duplicate analyses)
    Stone Fruit

         Data were available from three countries, all of which have
    approved uses, or are in close geographical proximity to countries
    with them. While European trials on peaches reflect recommended
    European dosage rates, applications were apparently made after the end
    of flowering, and therefore do not appear to reflect the recommended
    time of application (Table 1) for Europe. South African trials also
    reflect recommended application rates in that country, but the pre-
    harvest interval was not available to the meeting. The only available
    PHI for stone fruit was 21 days for cherries in one European country
    (see "National maximum residue limits". A 1 mg/kg limit for stone
    fruit can be supported at a 21-day pre-harvest interval. Additional
    residue data and good agricultural practice information for stone
    fruit are desirable, especially for small fruit such as cherries.

         Residues on peaches were significantly more persistent from WP
    applications than from EC formulations.


         Supervised trials data were available for three Asian and three
    South American countries and generally reflected the application rates
    and number of applications (WP or EC) recommended in those
    geographical areas. Since no national pre-harvest intervals were
    provided, it must be assumed that application on the day of harvest,
    as included in the trials, reflects practice. Data were available for
    both green and ripe, bagged and unbagged, and washed and unwashed
    bananas and on pulp and peel. In general, average residues were
    approximately 5-10 times higher in peel than in pulp, whether ripe or
    green, bagged or unbagged, washed or unwashed. As might be expected,
    residues were higher on unbagged fruit. Washing (in the field) does
    not appear to affect average residues significantly.

         Maximum residues on bagged bananas (whole, green, washed) were
    0.06 mg/kg. Maximum residues on whole ripe, unbagged, washed bananas
    were 0.28 mg/kg as compared to 0.36 mg/kg for green, unbagged, washed

    Untreated controls (peel, pulp or whole) were all <0.01 mg/kg. A 0.5
    mg/kg limit was estimated.

    Cereal crops

         No residues of bitertanol were detected in the green forage,
    ears, grain or straw of oats, rye or wheat when the seeds were treated
    pre-plant with recommended rates. The limit of determination ranged
    from 0.05 - 0.1 mg/kg among the 15 studies. The available data would
    support a limit of 0.1 mg/kg (at the limit of determination) limit for
    seed treatments only. Additional data from other countries with
    approved uses for cereal grains are desirable.



         The fate of bitertanol has been studied in animals, plants, soil
    water and light. A proposed metabolic pathway is given in Figure 1.
    The structures and chemical names are presented in Table 3 which also
    indicates where the compounds have been identified. Although the
    metabolic picture is somewhat limited in scope, the data in general
    demonstrate that metabolism in animals is much more extensive than
    degradation by other routes. Bitertanol is the predominant residue in
    plants. Bitertanol and p-hydroxybitertanol are the major residues in

    In plants

    Uptake and translocation.  Golden Delicious variety apples were
    individually syringe-treated to run-off with a 50% wettable powder
    formulation at 0.15 g a.i./l of 14C-bitertanol labelled
    uniformly (UL) in the biphenyl ring. Sampling was immediately after
    drying, at 3 and 7-days and thereafter at 7-day intervals through 49
    days (Phul and Hurley, 1979c). Analysis was by TLC using
    radiochromatogram scanning and autoradiography techniques. The peel
    contained 95% of the total recovered radioactivity even after 49 days,
    the rest being in the pulp, showing that little migration had
    occurred. Surface residues decreased from 92% at day 0 to 43% at 49
    days while the radioactivity in the peel organic extract increased
    from 7 to 43.5% of the total. Peel solids increased to 12% in the same

         The two diasterioisomers of bitertanol were the major residues,
    in roughly equal proportions throughout the 49-day study. The level of
    the two combined in peel and pulp ranged from 98.4% of the total
    radioactivity at day 0 to 83% at 49 days, with lower surface residues
    and greater peel uptake by the end of that time. The two had
    penetrated the pulp by day 7 from which time residues were relatively
    constant at about 3% over the remaining test period. Minor metabolites
    were bitertanol ketone and 4-hydroxy-biphenyl, together never
    exceeding 3% of the total radioactivity. All of these metabolites were
    in the peel. The half-life of bitertanol in this experiment was
    estimated at approximately 150 days.

         The metabolism of bitertanol by peanut plants has also been
    studied (Phul and Hurley, 1981). In preliminary studies, the authors
    obtained evidence that foliar applications result in poor leaf
    absorption (96% unchanged bitertanol on the leaf surface after 14
    days), with no observable volatility losses. Only very little
    translocation (acro- and basi-petal) was observed, as well as little
    translocation to opposite leaves Bitertanol - 14C uniformly labelled
    in the biphenyl ring was sprayed as a 50% WP formulation to both young
    (1 mo.) and old (2 mo.) potted peanut plants at an approximate
    equivalent field rate of 0.5 kg a.i./ha. Young plants were sampled at

    FIGURE 1

        Table 3. Bitertanol, its degradation products and their occurrence  a


    Chemical Name                              Common, trivial or        Soil      Water      Plant    Animal     Light
                                               code name


    P-(1,1'-Biphenyl)-4-yloxy-o-(1,1-          Bitertanol                X         X          X        X          X
    ethanol. Bitertanol


    1-[1,1-Biphenyl]-4-yloxy),3,3-             Bitertanol ketone         X                    X
    dimethyl-1-(1H-1,2,4-triazol-1-yl)-        BUE 1662


    4-(1,1'-Biphenyl)-4-yloxy)-2,2-            Bitertanol alcohol
    dimethyl-4-(1H-1,2,4-triazol-1-yl)         KWG 1714                                                X
    Note 1. 1,3-Butanodiol-1,3-butanediol

    Table 3. (continued)


    Chemical Name                              Common, trivial or        Soil      Water      Plant    Animal     Light
                                               code name


    -([1,1'-Biphenyl]-4-yloxy)-B-hydroxy-      Bitertanol acid                                         X
    1-yl)butyric acid


    -(1,1-Dimethylethyl)- -(4'-hydroxy         p-hydroxy-bitertanol                                    X
    1-(4'-hydroxy o)-3,3-dimethyl-1-(tr)


    Table 3. (continued)


    Chemical Name                              Common, trivial or        Soil      Water      Plant    Animal     Light
                                               code name


    4-(4'Hydroxy-[1-1'-biphenyl]-4-yloxy)                                                              X


    -Hydroxy- -(4'-hydroxy-[1,1'-              p-Hydroxy-bitertanol
    biphenyl]-4-yloxy-    -dimethyl-1H.1,2     alcohol                                                 X
    4-triazole-1-butanoic acid

    dimethyl-4-(tr)butyric acid


    Table 3. (continued)


    Chemical Name                              Common, trivial or        Soil      Water      Plant    Animal     Light
                                               code name


    - (1,1-dimethylethyl)-p-(x'-di-            Dihydroxy-bitertanol                                    X

    butan-2-olc(distal biphenyl ring


    -(1,1-Dimethylethyl)-B-(x-hydroxy-         Hydroxy, methoxyd
    x'-methoxy-[1,1'-biphenyl]-4-yloxy)-       bitertanol                                              X
    (tr)butan-2-old (distal biphenyl ring


    Table 3. (continued)


    Chemical Name                              Common, trivial or        Soil      Water      Plant    Animal     Light
                                               code name


     - Hydroxy- -(x'hydroxy-x'-methoxy-        Hydroxy,methoxyd
    [1,1'-biphenyl]-4-yloxy)-d,d-dimethyl      bitertanol acid.                                        X
    1H-1,2,4-triazole-1-butanoic acid
    dimethyl-4,4-(tr)butyric acidd
    (distal biphenyl ring substituted)


    4-([2-Hydroxy-3,3-dimethyl-1-[1H-          Bitertanol benzoic        X
    1,2,4-triazol-l-yl]butoxy)=benzoic         acid analogue
    acid                                         BUE 2684
    Note: Butoxybenzoic is one word


    Table 3. (continued)


    Chemical Name                              Common, trivial or        Soil      Water      Plant    Animal     Light
                                               code name


                                               Bitertanol glucoside                           X


    4-Hydroxybiphenyl                          p-Hydroxybiphenyl                   X          X        X          X


    Table 3. (continued)


    Chemical Name                              Common, trivial or        Soil      Water      Plant    Animal     Light
                                               code name


    4,4'-Dihydroxybiphenyl                     p,p,'-dihydroxy-
                                               biphenyl                                       X        X          X        X


    1,2,4-triazol                                                                                                          X


    Carbon dioxide                                                       X


    Table 3. (continued)

    a     An X indicates that the compound has been found to occur as a degradation product of bitertanol in the substrate 
          concerned (or on irradiation). A blank indicates it has not been found there, but does not exclude its presence in 
          amounts too small to detect.
    b     tr = 1-H-1,2,4-Triazol-l-yl
    c     The position of the hydroxy groups is uncertain
    d     The positions of the hydroxy and methoxy groups are uncertain.
    12 and 28 days after treatment and the older plants and nuts after 2.5
    months. In young plants, 61-72% of the total recovered radioactivity
    was surface residue, the remainder being mostly (27-36%) extractable.
    In the older plants the distribution was 46% surface and 50%
    extractable. In both cases most of the extractables were 
    organo-soluble. The composition of the residues is shown in Table 4.
    As in the case of apples most of the residue, both surface and
    extractable, was bitertanol I and II and a metabolite (R-1)
    tentatively identified as a bitertanol I glucoside.  Low levels of 4-
    hydroxybiphenyl (0.6% of the total shoot residues) were also detected.
    The authors conclude that the lower I:II isomer ratios in the surface
    residues in the older plants compared to the 1.33 ratio of the
    starting material indicates faster absorption of the I isomer and that
    the 1.10 ratio of I:II in the combined surface and absorbed residues
    gives evidence that isomer I is metabolized faster than II. Faster
    isomer I absorption is supported further by the 1.64 ratio of
    (bitertanol I + metabolite R-1):bitertanol II in the absorbed residues
    in the old plants and experimental evidence suggesting increased
    levels of the tentatively identified glucoside of isomer I (R-1) as
    opposed to isomer II. There is no convincing evidence as to whether
    isomeric conversion also occurs to account for the lower bitertanol
    I:II ratio in the total residue. The half-life in peanuts has been
    estimated at 141 days.

         In a similar and related experiment in the same set of studies
    with 8.9 mg a.i./plant (approximately twice the rate per plant in the
    above), residues in nut meats were 0.06 mg/kg bitertanol equivalent
    (0.008% of the total plant residue) 2.5 months after treatment. A
    similar level was found in the shells. It cannot be concluded from
    this study whether nut residues resulted from the foliar application
    or from soil uptake.

         Seven days after growing peanuts in a 1 mg/l 
    14C-biphenyl-labelled bitertanol nutrient solution followed by 7 days
    in an unfortified nutrient solution 94.3% of administered
    radioactivity was recovered with 28.8% in the roots, 14.9% in the
    shoots, 40% in the fortified nutrient solution and 10.6% in the 
    non-fortified solution. Radioactivity was concentrated in the veins,
    but distributed throughout the plant. No translocation to new growth
    occurred after removal of the fortified solution. Radioactivity in the
    non-fortified solution suggests desorption from within or from the

         Of the absorbed radioactivity, 32.1% was in the shoots and 67.9%
    in the roots with the distribution in the organo-soluble fraction
    shown in Table 5.

        Table 4.  Composition of bitertanol residues in peanut shoots following spray application of 
              14C-biphenyl-laballed bitertanol


                                        YOUNG PLANTS (1 month)                OLD PLANTS (2 months)
                                 12 day2    Ratio3   28 day2    Ratio3        2.5 mos.2  Ratio3

    Surface Residues
      bitertanol II              31.3       1.25     26.7       1.24          20.7       0.98
      bitertanol I               39                  33                       20.5
      metabolite R-11            -

    Absorbed (organosoluble)
      bitertanol II              11.2                                                    1.64
      bitertanol I               11.9       1.27     13.4       1.3           15
      metabolite R-1             2.4                 13.1                     18.9
                                                     4.3                      5.8

    1  Tentatively identified as the 6-0-malonyl-B-D-glucoside of bitertanol I.
    2  Interval after treatment.
    3  Ratio of bitertanol I to bitertanol II in surface residues; ratio of 
         (bitertanol I + metabolite R-1) to bitertanol II in absorbed residues.

        Table 5.  Distribution of organo-soluble radioactivity absorbed by peanut plants.


    Compound            Shoots                Roots               Total
                        % of      Ratio*      % of     Ratio*     % of         Ratio*
                        absorbed              absorbed            absorbed
                        14C                   14C                 14C

    bitertanol II       10.7                  20.4                31.1         1.32

    bitertanol I        8.6       1.17        16.1     1.39       24.7

    metalite R-1        3.9                   12.3                16.2
                        23.2                  48.8                72.0

    Ratio of (bitertanol I + metabolite R-i) to bitertanol II.
         Unextracted residues were 18.3% of the absorbed activity.
    Assuming R-1 is a glucoside of bitertanol I as postulated the ratio of
    (I + R-1) to II (1.32) n the total absorbed residue is essentially
    identical to that in the starting material. This suggests equal root
    absorption rates of bitertanol I and II. The finding of higher levels
    of both R-1 and bitertanol I in the roots than in the shoots suggests
    faster translocation of bitertanol II through-out the plant and/or
    more rapid metabolism of bitertanol I. There was no evidence of
    volatility from leaf surfaces.

         Of the 18.3% unextracted but absorbed residue, 5 and
    13.3%, respectively, was in shoots and roots. The metabolite
    4-hydroxybiphenyl was detected in both (64% of the root-concentrated

         Other peanut studies (Scheinpflug and Van den Boom, 1981) also
    show bitertanol to be slowly absorbed by peanut leaves from surface
    application with little translocation from petiole applications.

    In animals

         The fate of residues in rats and other non-food animals was
    evaluated by the 1983 meeting. This evaluation considers the fate in
    cows and chickens.

    Cow.  A single dose of phenyl-UL-14C bitertanol was fed to a
    341 kg Holstein dairy cow at 0.2 mg/kg body weight by gelatin capsule,
    and excreta and milk were analyzed periodically for six days. The I:II
    isomer ratio was 53:47. Food consumption was not recorded (Obrist et
    al. 1981). Eighty per cent of the dose was eliminated within 48
    hours: urine 8.3%, faeces 70.4% and milk 0.2%, with milk residues
    becoming steady after 32 hours. Ninety two per cent was eliminated by
    6 days. Residues in the blood peaked at
    0.13 mg/l after 12 hours.

         Six days after the single dose the same cow was dosed daily at
    the same rate for an additional 5 days. The 14C residues (as
    bitertanol equivalent) in tissues and milk, 2.5 hours after the last
    dose were: liver 0.82 mg/kg; kidney 0.11 mg/kg; muscle
    0.01 mg/kg; fat 0.03 mg/kg; milk 0.008 mg/l.

         The 0.008 mg/l in milk from the multiple dosing is comparable to
    0.009 mg/l found from the single dosing. None of the residues were
    identified. Summary data were provided on the identity and
    distribution of residues in the tissues, milk and urine of cows fed
    UL-14C-phenyl-labelled bitertanol at 0.2 mg/kg, but the study itself
    was not provided (Obrist, et al, 1983).

    Chickens.  Laying hens (average weight 1170g) were administered
    single oral doses of 14C-phenyl-UL bitertanol (I:II isomer ratio
    53:47) by gelatin capsule at 2.5 mg/kg body weight for excretion
    studies (5 trials) and blood level determinations (10 birds). Three
    birds were dosed daily for 5 days at a rate of 8 mg/kg body weight for
    tissue analyses. Food consumption data were not provided (Obrist et
    al, 1982).

         From a single dose, 92% was eliminated in the excreta within 24
    hours with <0.1% in eggs (0.2% by 96 hours). Bitertanol equivalents
    after 4 days were 0.1 and 0.02 mg/kg in liver and kidney respectively
    (both 2X standard deviation) and <0.006 mg/kg in other tissues. In
    eggs, residues as bitertanol equivalent from a single dose ranged from
    <0.002 mg/kg (limit of determination) after 24 hours to 0.061 mg/kg
    (2X standard deviation) after
    96 hours. Dose-dependent residues from the multiple doses ranged from
    <0.002 to 0.38 mg/kg for the same time interval.

         Tissue and blood plasma residues, as bitertanol equivalent,
    45 minutes after the last of the 5 daily doses varied significantly
    (by factors of 5-20) among the 3 birds. They are shown in Table 6.

         The composition of the chicken tissue residues is given in Table
    7, where it can be seen that bitertanol and p-hydroxy-bitertanol were
    by far the main residues, with the latter predominating in liver,
    kidney and eggs, whereas bitertanol was predominant in the other
    tissues. Conjugation was also greater in liver, kidney and eggs.
    Combined unidentified and unextracted residues accounted for up to 19%
    of the chicken liver residue and less in other tissues.

         Residues in excreta (single dose) were 69.5% 
    p-hydroxy-bitertanol, 6.7% bitertanol, 13.7% unidentified and <3%
    each of other identified compounds. The same residues were identified
    in excreta as in tissues with the exception of dihydroxy-bitertanol,
    found only in the liver. Bitertanol acid and 
    p-hydroxy-methoxy-bitertanol acid found in rat faeces (Phul and
    Hurley, 1983) were not identified in chicken excreta or tissues.

         Summary data provided to the meeting (from Obrist et al 1983)
    suggest that residues in cow tissues and milk are similar
    qualitatively, and in some respects quantitatively, to those in
    chicken tissues except that the dihydroxy-bitertanol found in chicken
    livers was reportedly not identified in dairy cow tissues or excreta.
    Cow urine reportedly contained bitertanol acid and
    p-hydroxy-bitertanol acid, also identified in rat urine (Phul et
    al 1979b). The cow study itself was not provided. Further evaluation
    must await availability of the study.

    Table 6.  Tissue and plasma residues in chickens dosed with 14C


                                          14C residue
    Tissue            Bitertanol equivalent,mg/kg    % organo-soluble
                      Mean          Max

    liver             6.2           12.6                   86

    kidney            4.3           10.3                   91

    breast muscle     0.35          0.91                   95.2

    leg muscle        0.48          1.1

    fat               1.4           3.01                   93.2

    gizzard           0.72          1.7                    90.8

    heart             1.3           3.2                    92.9

    skin              0.63          1.4                    94.7

    blood plasma      1.8           4.5                    --

        Table 7.  Composition of residues in chicken tissues following administration of multiple oral doses of 
              bitertanol-phenyl-UL 14C at 8.0 mg/kg (from Obrist and Phul, 1982)


                                                                % of 14C in each tissue occurring as named compound
                                            Liver    Kidney     Muscle        Gizzard    Heart         Fat        Skin      Eggs

    Bitertanol                              34.7     27.2       67.8          62.4       66.0          78.2       74.9      36.6

      Free                                  14.7     27.7       23.2          14.8       17.1          12.1       13.2       6.4

      Conjugateda                           25.4     24.8        1.5          10.4        4.4            -         4.2      37.9

    Hydroxy, Methoxy-bitertanol
      Free                                   0.2      1.0         -             -          -             -          -        0.3

      Conjugateda                            1.5      1.2         -             -          -             -          -        0.7

    Bitertanol alcohol
      Free                                   1.2      1.8         -             -          -             -          -        0.5

      Conjugated                             0.8      1.1         -             -          -             -          -         -

    Dihydroxy-bitertanolb                    0.9       -          -             -          -             -          -         -

    p-Hydroxy-bitertanol alcohol
      Free                                   0.4      0.9         -             -          -             -          -        0.3

      Conjugateda                            0.2       -          -             -          -             -          -         -

    p-Hydroxy bipbenyl                       0.2      0.2         -             -          -             -          -        1œ3


    Table 7.  (continued)


                                                                % of 14C in each tissue occurring as named compound
                                            Liver    Kidney     Muscle        Gizzard    Heart         Fat        Skin      Eggs

    p,p'-Dihydroxybiphenyl                    0.7      0.2        -             -          -             -          -         -

    Unidentified residue                     11.9     12.0        4.9           5.9        5.4           2.9        2.4       9.3

    Unextracted                               7.2      1.9        2.6           6.5        7.1           6.8        5.3       6.7

         TOTALS                             100.0    100.0      100.0         100.0      100.0         100.0      100.0     100.0
         The accumulation, persistence and composition of residues of
    14C-bitertanol in bluegill fish maintained in aquarium water
    fortified at 10 and 10 mg/l for 30 days has been investigated (Lamb,
    1979). Residues on a whole fish basis reached a plateau in both cases
    by three days at 2.1 and 16.2 mg/kg at the 10 and 100 mg/l
    concentrations respectively, with maximum concentration factors of 203
    and 174 respectively.  Residues were quantitatively extracted with
    acetonitrile with 57-66% of the radioactivity in non-edible parts
    (head, viscera, scales) and 34-43% in edible parts. Residues were
    characterized by TLC as bitertanol II 40%; bitertanol I 34%;
    metabolite R-2 (unidentified) 7%; remaining at origin 13%; other
    unidentified 6%.

         Approximately 96% of the residues were excreted within 3 days
    when the fish were transferred to untreated water.

    In soil

    Adsorption/desorption.  In soil adsorption/desorption studies
    bitertanol was shown to be strongly adsorbed to three soils in the
    decreasing order: sand, loam and silty clay with adsorption
    coefficients (K values) of 39.9, 35.8 and 19.6 (Phul and Hurley,
    1979a). The data conformed to the Freundlich equation and in each case
    >84% was adsorbed under experimental conditions. Only 4-10% of the
    adsorbed compound was desorbed from sand.

    Leaching.  In TLC leaching experiments six soil types were examined
    by comparing Rf values (Obrist and Thornton, 1979). The Rf values
    ranged from 0.04 to 0.22, which places bitertanol in the two lowest
    mobility ranges of the five classes which have been proposed (Helling
    and Turner, 1968; Helling et al 1971). This is consistent with the
    high adsorption determined in adsorption experiments.  No significant
    difference was observed between the two bitertanol isomers.

         In aged soils (moist sandy loam) 44% of the initial radioactivity
    was lost during room temperature incubation for 30 days, probably by
    volatilization (Obrist, 1979). Less than 2% of the aged applied
    bitertanol was found in the leachate from 30 cm soil columns, leached
    at an equivalent of 13 mm/day for 45 days. Except for 55% further
    losses during leaching, most of the remaining residue was in the upper
    1.3 cm of the column.

         Similar results were found in 19 studies with either Dutch polder
    soil or a standard loamy sand containing aged bitertanol residues
    leached at an equivalent of 200 mm for 48 hours or up to 500 mm in
    polder soil after 72 additional hours (Brennecke, 1983). Only 0.8% of
    the aged soil residue was found in the leachate of polder soil after
    48 hours, and 3% after 120 hours. In experiments with 11 standard
    soils, the leachates contained <6.6% of the original radioactivity in
    the aged soil in all but one sample, where 48.9% was in the leachate
    and was identified as the bitertanol soil metabolite 
    4-[2-hydroxy-3,3-dimethyl-(1H-1,2,4-triazol-1-yl)butoxybenzoic acid
    (BUE 2684). A repeat of this experiment resulted in only 2.1% or less

    of aged residue in the leachate, although less leachate (approximately
    400 ml) was collected in the repeat, compared with approximately 650
    ml in the original experiment. No unchanged bitertanol was found in
    any leachate. Most leachate residues were BUE 2684 and traces of its
    methyl ester.

         The low leaching potential of bitertanol under experimental
    conditions was supported by 30 additional reports provided to the

    Soil persistence.  The soil persistence of bitertanol applied to 7
    soil types as the 25 WP formulation at 11 kg a.i./ha to field plots in
    9 studies in scattered locations in North America was reported in 9
    Mobay reports (68296-68304). Half-lives ranged from 10 to 39 days with
    an average of 25 days, except in one study with Oregon loam in which
    the half-life was 131 days. The exceptionally long half-life did not
    appear to be accounted for by temperature, rainfall, pH or
    geographical area when compared to other studies.

         Under laboratory aerobic conditions the half-life on silt loam
    ranged from 14 to 20 days (Phul and Hurley, 1979b). Degradation was
    slower under anaerobic conditions and there was no significant
    degradation in sterilized soil after 31 days, showing the importance
    of soil micro-organisms in bitertanol degradation. Both
    diasterioisomers of bitertanol were degraded at approximately the same

         Under laboratory conditions bitertanol decomposed faster in
    alluvial loam soil (12 day half-life) than volcanic ash loam soil (30
    days half-life), while under field conditions decomposition was faster
    with volcanic ash/sandy loam than with alluvial loam soil (Takase and
    Yoshimoto, 1980).  In other laboratory tests bitertanol had a 
    half-life of 26 days in type 1 soil and 72-days in type 2 (Mobay
    Report No. 10.317/18), while in field tests half-lives ranged from 19
    to 27 days (Mobay Reports NO. 10.324/79, 10.325/79, 10 311/80 and

    Rotational Crops.  The uptake of 14C-biphenyl ring-labelled WP
    bitertanol by rotational crops planted 31, 118 and 364 days after the
    last of eight applications to outdoor tub-planted peanuts at an
    equivalent of 0.56 kg a.i./ha resulted in 14C residues in leafy
    vegetables at harvest ranging from 0.1 mg/kg bitertanol equivalent in
    the 118-day planting to 0.02 mg/kg in the 364-day planting (Phul et
    al. 1981). In sugar beets residues were 0.38 and 0.01 mg/kg for the
    same plantings, and in wheat heads 0.23 and 0.01 mg/kg for 31-day and
    364-day plantings. Residues in wheat straw were 1.4 mg/kg from the 
    31-day planting. The organo-soluble portion of the residue was
    <0.04 mg/kg bitertanol equivalent in all at-harvest samples except
    for 0.51 mg/kg in wheat straw. The benzoic acid derivative of
    bitertanol, BUE 2684 was identified in the 31-day wheat samples.

    Soil transformation.  The fate of bitertanol has been investigated
    in silt loam soil (pH 7.4) under aerobic and anaerobic conditions and
    in sterile soil (Phul and Hurley, 1979b). Soil was fortified at 1 and
    10 mg/kg for aerobic conditions and 1 mg/kg for anaerobic and sterile
    conditions. One mg/kg approximates the maximum residues expected from
    recommended field rates of 0.56 kg a.i./ha applied to peanuts. In the
    1 mg/kg experiment, bitertanol (I + II) and total organo-solubles
    decreased from 98.6 and 99.8% of the total 14C on the first day to 6
    and 8.4% after 121 days, while 14CO2 and unextracted residues
    increased from 0.8 and 4.6% on day 3 to 45.8 and 45% of the total
    radioactivity, respectively, after 121 days. A similar trend was
    observed with the 10 mg/kg fortification over the 29-day period
    examined. The two diasterioisomers of the bitertanol benzoic acid
    metabolite were observed at the 10 mg/kg fortification level (8.6% of
    the total radioactivity) but not at the 1 mg/kg level.

         Degradation was somewhat slower under anaerobic conditions than
    aerobic, but the distribution (bitertanol, total organic, 14CO2 and
    unextracted) was not markedly different at comparable intervals.

         Bitertanol still accounted for 95.4% of the total 14C in sterile
    soil after 31 days compared to 11% in non-sterile soil, indicating the
    importance of soil microbes in the metabolism of bitertanol; this was
    further demonstrated in another study (Phul et al 1979a). The
    identity of the microbes present in the soil of the latter study was
    investigated by Smedly and Hepler (1979).

         In other studies (Brennecke, 1982) 14C-biphenyl-labelled
    bitertanol was shown to be mineralized primarily into 14CO2, up to
    68% in "standard soil 2.1" and 49% in Netherlands polder soil. The
    bitertanol benzoic acid metabolite BUE 2684 (<19.1%) and an unknown
    (<1%) were also found in one of 5 experiments in standard soil.
    Bitertanol ketone (BUE 1662) was identified by TLC at <1.7% of the
    total radioactivity in polder soil.

    In water

         The stability of bitertanol in sterile aqueous solutions has been
    studied (Nichols and Thornton, 1979). No apparent degradation was
    observed after thirty days in sterile aqueous solutions, buffers at pH
    4, 7 and 9 and maintained at 25 and 40°C, which contained 0.25 and 2.5
    mg/l of bitertanol. After 30 days, 94-109% of the bitertanol was
    accounted for at the higher concentrations and 85-98% at the lower
    level. The 85% recovery was from 0.25 mg/l at pH 9 and 40°C. The
    slightly lower recovery at the lower fortification level was
    attributed to adsorption to the vials. This is consistent with the
    adsorption observed at low concentration in other studies (Phul and
    Hurley, 1979). After using a correction factor to account for vial
    glass adsorption, the recovery was 100% under all conditions of this

         Additional information on the hydrolytic stability of bitertanol
    was provided (Stegh, 1980) but not in the working language of the


         The photolysis of bitertanol has been investigated on soil and
    silica surfaces and in water. In the soil surface experiment,
    bitertanol-treated silt loam of 1 mm thickness irradiated for 35 days
    did not show substantially different extractability (91.5%) from dark
    controls (96.6%), (Sietsema, 1982). Volatile radioactivity accounted
    for <0.1% of the original amount. The extracted residue was shown to
    be bitertanol by mass spectrometry.

         A study on the photolysis of bitertanol on silica gel places
    (Stegh and Wilmes, 1982) and two reports on the photolysis in water
    and on silica gel (Wilmes, 1980; Stegh, 1980) were provided, but not
    in the working language of the meeting. Another report (Wilmes, 1981)
    discussed the hydrolytic behaviour and stability of bitertanol in
    solution. No data were provided, but reference was made to the two
    studies above which included data. Another bitertanol photolysis study
    (Sietsema, 1983) was brought to the attention of the meeting, but was
    not included in the data provided.


         An analytical method developed for the analysis of triadimefon in
    apples (Thornton, 1977) has been used for bitertanol in apples. The
    sample is ground with dry ice, blended with acetone and filtered. The
    filter cake is blended with dichloromethane and filtered, and the
    combined filtrates are partitioned with water, taken to dryness and
    cleaned up on a Florisil column with 60:40 hexane:ethyl acetate as
    eluant. The eluate is concentrated and bitertanol determined by GLC
    using an alkali flame detector.

         The procedure was validated for bitertanol in apples at
    0.05-0.1 mg/kg with recoveries of 86-108% and a blank of
    <0.01 mg/kg (Morris, 1979a)  Although detection was easily attainable
    at 0.05 mg/kg and probably 0.01 mg/kg, chromatograms showed
    interferences which would make quantitation below 0.05 mg/kg

         Interference studies have demonstrated that the basic procedure
    above permits analysis of bitertanol at levels equivalent to 0.1 mg/kg
    in samples in the presence of tolerance levels of 75 pesticides
    registered in the U.S.A. for apples or peanuts (1979), five compounds
    registered for bananas (1980) and three compounds registered for
    cherries, plums, peaches and pears (1981) (Obrist and Nichols,1979). 
    Several compounds interfered, but could be eliminated by a 1-hour
    reflux with 1 N NaOH and zinc or by partitioning with 0.1 N HC1.
    However, analytical recoveries from a crop matrix with these steps
    incorporated were not provided.

         Another analytical procedure (also suitable for other crop
    protectants) has been tested for bitertanol on apples, bananas, beans,
    currants, cherries, damsons, wheat (green, grain and straw) and soil
    (Specht and Tillkes, 1980). Many of the analyses in the field trials
    were conducted with this basic procedure. Samples are extracted with
    2:1 acetone: water, partitioned with dichloromethane, cleaned up by
    gel permeation chromatography and analyzed by GLC utilizing a flame
    alkali detector. Where necessary (e.g. for straw) an additional silica
    gel column clean-up is used. Analytical recoveries were 74-112%,
    although fortification levels were described only as "0.02-0.1 ppm
    (lower limit of determination), and 1.0-3.0 mg/kg". For the compounds
    tested, the authors concluded that the lower limit of determination
    was 0.02 to 0.05 mg/kg for plants with >70% water content and 0.1
    mg/kg for cereals and soil. The information was not sufficient for the
    meeting to draw a conclusion on the limit of determination.

         A method developed for triadimefon in soil and water (Thornton
    and Lloyd, 1977) is also suitable for bitertanol in soil and water
    with minor modifications in the GLC column stationary phase (Morris,
    1979b). Water is simply extracted with chloroform, the extract is
    concentrated (a Florisil column clean-up is optional), and analyzed by
    GLC using a flame-alkali detector. Soil is extracted by refluxing with
    methanol/water, partitioned with chloroform, washed with water and
    cleaned up on a Florisil column. Recoveries from water fortified at
    0.005 and 0.01 mg/l were 94% and 78% respectively with a blank of
    <0.001 mg/l. Recoveries from six soils fortified at 0.05-0.5 mg/kg
    ranged from 76 to 121% (most were >90%) with blanks <0.01 mg/kg
    (Morris, 1979b). Chromatograms were consistent with the data.

         In a similar procedure for the analysis of bitertanol and
    numerous other fungicides in water (Brennecke and Vogeler, 1980),
    extraction is with dichloromethane and clean-up by gel permeation
    chromatography. The two recoveries for bitertanol were 108% and 104%
    for 0.005 and 0.5 mg/l fortifications respectively. The lower limit of
    determination was said to be 0.005 mg/l, although the meeting could
    not confirm this with the available data.


         The following national MRLs were reported to the meeting.


                                                interval     MRL
    Country             Crop                    (days)       mg/kg

    Australia           Apples                  14           1.0 1)
                        Peanuts                 14           0.2 1) 2)

    Belgium             Apples                  42           0.25
                        Pears                   42           0.25

    France              Apples                  15           1.0
                        Pears                   15           1.0

    Germany, Federal    Apples                  14
    Republic            Cherries                21

    Great Britain       Apples                  21
                        Pears                   21

    Greece              Apples                  21
                        Beans 4 crops           14
                        Pears 5 PHIs            7
                        Stone fruit             14

    Israel              Apples                  14

    Italy               Pears                   14
                        Beets                   30           1.0
                        Fruit                                1.0
                        Pome fruit              21
                        Stone fruit             21
                        Vegetables              14           0.5

    Morocco             Beans                   15

    Netherlands         Apples                  14
                        Blackberries                         0.05 2)
                        Cucumbers               3
                        Fruiting Vegetables                  1.0
                        Melons                  3
                        Pears                   14
                        Peppers                 3
                        Other commodities                    03)(0.05)

    New Zealand         Pome fruit              14
                        Strawberries            21



                                                interval     MRL
    Country             Crop                    (days)       mg/kg

    South Africa        Apricots                56           0.5
                        Beans                   28           0.1
                        Beans (fodder)          42
                        Peaches                 56           0.5
                        Peanuts                              0.05
                        Peanuts (fodder)        42
                        Plums                   56           0.5

    Spain               Pome fruit              15 1)
                        Stone fruit             15 1)

    Switzerland         Pome fruit              42           0.6

    Venezuela           Apples                  15           1.0
                        Broad beans             28           1.0
                        Peanuts                              0.2 (1)
                        Pears                   15           1.0
                        Stone fruit             42           0.6

    Yugoslavia          General                 28

    1) = Preliminary
    2) = Level at or about the limit of determination.
    3) = No residues should be present. Limit of determination 0.05 mg/kg.


         Bitertanol is a relatively new broad-spectrum fungicide
    introduced and being introduced in a number of countries. Its
    toxicology was evaluated by the 1983 JMPR which estimated a temporary
    ADI. The present meeting evaluated residues in food.

         To date only limited residue trials data have been provided and
    these have been evaluated. Data were insufficient to estimate residue
    levels in cucumbers and beans, but temporary limits were estimated for
    several commodities.

         The fate of bitertanol has been investigated in plants (apples
    and peanuts), animals, soil, light and water.

         In the plant studies bitertanol penetration from surface
    applications was minimal and there was little volatility. Residues are
    taken up by roots, although translocation into the plant is relatively
    low. There are some measurable but not major differences in
    absorption, translocation and plant metabolism rates of the
    two diasterioisomeric forms of bitertanol. Bitertanol is by far
    the main plant residue, with low levels of its ketone and
    4-hydroxybiphenyl. In apples, most of the residue in the peel.

         The fate of residues in non-food animals was evaluated by the
    1983 JMPR. The present meeting evaluated metabolism studies on
    poultry, cows and fish. Bitertanol is metabolized substantially more
    in animals than in plants. The products are rapidly excreted but low
    residues can occur in milk, eggs and tissues. These are predominantly
    in the liver and kidney, as demonstrated with exaggerated feeding
    levels. Bitertanol and p-hydroxy-bitertanol are by far the predominant
    residues in chicken tissues and eggs and are reported to be the major
    residues in cow tissues and milk, although other metabolites occur at
    significant levels in the latter. Although cow metabolism studies were
    available to the meeting the only one detailing the distribution of
    identified residues was received too late for evaluation, until it has
    been reviewed at a future meeting, no final conclusion can be drawn on
    the adequacy of information on the fate of residues in animals. The
    available data indicate that metabolism appears to be similar among
    rats, poultry and cows.

         Conventional feeding studies on poultry and ruminants, an
    analytical method for the analysis of bitertanol in animal products,
    and information on the fate of residues in apples during processing
    were all received too late for evaluation.

         Extensive information was available to the meeting on the fate of
    bitertanol residues in soil, in which it is of low mobility, and some
    data were available on water stability and photolysis. The water and
    photolysis data available in the working language of the meeting
    indicate a high degree of stability in each case. Other studies
    provided, but not in the working language of the meeting, were not

         Several analytical methods utilizing solvent extraction, GPC or
    Florisil clean-up followed by gas chromatography are available for
    determining residues in crops, soil and water. Further confirmation of
    the limit of determination is desirable.

         No information was provided on the fate of residues in storage,
    in processing, in commerce or at consumption.

         The meeting examined residue data from supervised trials
    reflecting good agricultural practice on a number of crops and was
    able to estimate the maximum residue levels which were likely to occur
    when bitertanol was used in practice and when the reported intervals
    between the last application and harvest were observed. These levels
    refer only to the parent compound.



    COMMODITY       MRL (mg/kg)1          Pre-harvest interval on 
                                          which recommendations
                                          are based

    Apples          2                                14
    Stone fruit     1                                21
    Bananas         0.5                              0
    grain           0.1*  )
    forage          0.1*  )
    straw           0.1*  )
    grain           0.1*  )
    forage          0.1*  )
    straw           0.1*  ) from seed treatment
    grain           0.1*  )
    forage          0.1*  )
    straw           0.1*  )

    *  At or about the limit of determination.
    1  Temporary irrespective of the status of the ADI.


    1.   Except for bananas for which substantial data reflecting approved
         uses were available, additional information on good agricultural
         practice and residue data reflecting approved uses for all
         commodities for which temporary limits have been estimated.
         Residue data should be from countries from which details of
         approved uses have been or will be provided, or those in close

    2.   Additional plant metabolism studies.

    3.   Additional residue data reflecting good agricultural practice for
         additional plant products likely to be used as animal feeds.


    1.   Analytical recoveries through the Thornton analytical method
         utilizing the NaOH and HC1 steps designed to remove

    2.   Confirmation of limits of determination for the Specht method.

    3.   Information on the stability of residues in crops during cold

    4.   Additional national maximum residue limits and safety intervals.

    5.   Photolysis/hydrolysis studies in English (Stegh and Wilmes, 1982;
         Wilmes, 1980; Stegh 1980 and Sietsema, 1983).


    Mobay Reports are unpublished reports prepared by the Research and
    Development Dept., Agricultural Chemicals Division, Mobay Chemical
    Corporation, Kansas City, Mo. 64 120, USA.

    Nitokuno Reports are unpublished reports prepared by Nihon Tokushu
    Noyaku Seizo KK., No. 8, 2-chome, Nihonbashi, Chuo-ku, Tokyo, Japan.

    Bayer Reports:

         Leaching in Soil

         10.314 - 10.316/78  10.342 - 10.334/82
         10.318 - 10.320/78  10.348 - 10.350/82a
         10.334 - 10.336/80  10.374 - 10.376/82
         10.334A - 10.346A/8010.379 - 10.381/82b
         10.309  - 10.311/81 10.388 - 10.390/82b

         Soil Persistence

         10.317/78      10.324/7910.3257910.311/8010.312/80
         68 296         68 29868 30068 30268 304
         68 297         68 29968 30168 303

    Brennecke, R. Leaching characteristics of Aged [biphenyl-UL-14C]
    1983      bitertanol Soil Residues. Unpublished Bayer Report RA
              981/209B, October 1983.

    Brennecke, R. and Vogeler, K. Method for the Gas Chromatographic
    1982      Determination of Residues of Various Fungicides in Water.
              Bayer AG, Pflanzenschutz-Anwendungstechnik, unpublished
              Report RA-80, January, 1982.

    Helling, C.S. and Turner, B.C. Pesticide Mobility: Determination by
    1968      Soil Thin-Layer Chromatography, Science 162, 562 (1968).

    Helling, C.S., Kearney, P.C. and Alexander, M. Behaviour of Pesticides
    1971      in soils, Advan. Agron. 23; 147, 1971.

    Lamb, D.W., BAYCOR-14C Accumulation and Persistence of Residues in
    1979      Bluegill. Mobay Report No. 68 343 December 13, 1979.

    Mobay, Recovery Reports, Apples 68 249, Soil and Water 69 250.

    Morris, R.A. Recovery of Baycor from Apples. Unpublished Mobay Report
    1979a     68 249, November 19, 1979.

    Morris, R.A. Recovery of Baycor from Soil and Water. Unpublished Mobay
    1979b     Report 68 250, 1979.

    Nichols, S.S. and Thornton, J.S. The Behaviour of BAYCOR in Sterile
    1979      Aqueous Solutions. Mobay Report No. 68 273. October 22,

    Christ, J.J. Leaching Characteristics of Aged BAYCOR Soil Residues
    1979a     Mobay Report No. 68 271. September 25, 1979.

    Obrist, J.J. and Nichols, S.S. An Interference Study for the BAYCOR
    1979      Residue Method for Apples and Peanuts. Mobay Report No. 68
              311. November 27, 1979.

    Obrist, J.J., Phul, R.J. and Thornton, J.S. Excretion and Tissue
    1981      Levels of 14C  Following Oral Administration of BAYCOR-
              Phenyl-UL-14C to a Dairy Cow. Mobay Report NO. 69 400.
              March 24, 1981.

    Obrist, J.J., Phul, R.J. and Thornton, J.S. The Metabolism and
    1982      Excretion of BAYCOR-Phenyl-UL-14C by Chickens. Mobay Report
              No 82614. October 8, 1982.

    Obrist, J.J., Phul R.J. and Thornton, J.S. The Metabolism and
    1983      Excretion of BAYCOR-Phenyl-UL-14C Following Oral
              Administration to a Dairy Cow. Mobay Report, Manuscript in
              Preparation. 1983.

    Obrist, J.J. and Thornton, J.S. Soil Thin-Layer Mobility of BAYCOR,
    1979      BAYTAN, DYRENE, and PEROPAL. Mobay Report No. 68 272.
              October 22, 1979.

    Phul, R.J. and Hurley, J.B. Soil Adsorption and Desorption of BAYCOR.
    1979a     Mobay Report No. 68 003. July 18, 1979.

    Phul, R.J. and Hurley, J.B. The Metabolism and Degradation of BAYCOR-
    1979b     Biphenyl-UL-14C on Soil. Mobay Report NO. 67 998. August 6,

    Phul, R.J. and Hurley, J.B. The Metabolism of BAYCOR-Biphenyl-UL-14C
    1979c     in Apple Fruit. Mobay Report No. 68 305. November 5, 1979,
              Revised February 3, 1981A.

    Phul, R.J. and Hurley, J.B. Metabolism of BAYCOR-UL-14C in Peanut
    1981      Plants. Mobay Report No. 69 310. October 23, 1979, Revised
              June 18, 1981b.

    Phul, R.J. and Hurley, J.B. The Absorption, Excretion and Metabolism
    1983      of BAYCOR-Phenyl-UL-14C by Rats. Mobay Report, Manuscript
              in Preparation, 1983.

    Phul, R.J., Hurley, J.B. and Close, C.L. Total Radioactive Residues in
    1981      Rotational Crops Following a Target Drop of Peanuts Treated
              with BAYCOR-14C. Mobay Report No.80 059. September 11,

    Phul, R.J., Hurley, J.B. and Thornton, J.S. The effect of Soil
    1979a     Microorganisms on the Degradation of BAYCOR. Mobay Report
              No. 69 012. July 2, 1979.

    Phul, R.J., Obrist, J.J. and Pither, K.M. The excretion of
    1979b     BAYCOR-Phenyl-UL-14C Following Administration of a Single
              Oral Dose to Rats. Mobay Report NO. 68 307. November 19,

    Scheinpflug, H. and van den Boom, T. BAYCOR, A New Fungicide for
    1981      Tropical and Subtropical Crops.  PflanzenschutzNachrichten
              Bayer 34, 8-28.1981.

    Sietsema, W.K. Photodecomposition of BAYCOR on a Soil Surface. Mobay
    1982      Report No. 82 572. November 16, 1982.

    Sietsema, W.K. Photodegradation of BAYCOR in Water. Mobay Report (in
    1983      Preparation). 1983.

    Smedly, L.A. and Hepler, D.I. Identification of Microorganisms in
    1979      Samples of Kansas Loam Soil. Mobay Report No. 67 814. May 1,

    Specht, W. and Tillkes, M. Determination of Agrochemicals After
    1980      Clean-up using Gel Permeation Chromatography and Mini-Silica
              Gel Column Chromatography. Pflanzenschutz-Nachrichten Bayer
              33, 61 - 85. 1980.

    Stegh, R. Versuche zum Abbau von KWG 0599 in wässerigen Salzlosungen.
    1980      Bayer Experimental Notice. January 24, 1980.

    Stegh, R. and Wilmes, R. Light Induced Degradation of Agrochemical
    1982      Parent Compounds on Silica Gel as a Model for Degradation on
              Soil. Bayer Ag. Pflanzenschutz-Anwendungstechnik unpublished
              report PF1666. February 10, 1982.

    Takase, I. and Yoshimoto, Y. Residues of KWG 0599 in Upland Soils
    1980      Under Laboratory and Field Conditions.  Nitokuno Report No.
              1134. December 5, 1980.

    Thornton, J.S. A Gas Chromatographic Method for BAYLETON and its
    1977a     Metabolite in Apples. Mobay Report No. 54 166. December 30,

    Thornton, J.S. A Gas Chromatographic Method for BAYLETON and KWG 0599
    1977      in Soil and Water. Mobay Report NO. 51 231. January 31,

    Wilmes, R. Preliminary Studies on Stability to Light. Bayer Pharma
    1980      Unpublished Report, 1980.

    Wilmes, R. Abiotic Degradation of Bitertanol. Bayer summary Report.
    1981      March 31, 1981.

    See Also:
       Toxicological Abbreviations
       Bitertanol (Pesticide residues in food: 1983 evaluations)
       Bitertanol (Pesticide residues in food: 1987 evaluations Part II Toxicology)
       Bitertanol (JMPR Evaluations 1998 Part II Toxicological)