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    PROPARGITE     JMPR 1977

    IDENTITY

    Chemical names

    2-(4-tert-butylphenoxy)cyclohexyl prop-2-ynyl sulphite
    2-(p-tert-butylphenoxy)cyclohexyl propargyl sulphite

    Synonyms

    Omite(R), DO 14, ENT 27226

    Structural formula

    CHEMICAL STRUCTURE 11


    Other information on identity and properties

    The technical grade material is a light to dark brown liquid of low
    volatility. It is miscible with most organic solvents. Solubility in
    water is about 0.5 mg/kg. The basic manufacturer states the
    composition of the technical product to be:

         85%  active ingredient
         7%   "high molecular weight sulphites"
         5%   "unreacted starting materials"
         1%   propylene oxide stabilizer

    (remainder unidentified)

    Propargite is commercially available in 68.1% and 755% emulsion
    concentrates, a 30% wettable powder, and a 4% dust. The manufacturer
    states that the technical product shows no degradation after 12 months
    when stabilized with propylene oxide. The odour of SO2 indicates
    breakdown.

    The product was introduced in the U.S.A. on an experimental basis in
    1967 as a replacement for Aramite, another product of the same
    manufacturer, which was withdrawn from use on food crops in the U.S.A.
    The two compounds have similar chemical structures and properties.

    EVALUATION FOR ACCEPTABLE DAILY INTAKE

    BIOCHEMICAL ASPECTS

    Absorption, distribution, excretion and biotransformation

    Extensive degradation of propargite could be shown in in vitro as
    well as in vivo experiments.

    In vitro studies with liver homogenates showed that the major
    primary metabolites appear to be propargyl alcohol, the glycol ether
    and their conjugates, which are further degraded to secondary
    metabolites (Sullivan, 1968).

    In in vivo metabolism studies in rats that were orally treated with
    a single dose of 200 mg/kg propargite, propargyl alcohol and glycol
    ether were also found as primary metabolites in the excreta as well as
    in tissue samples. Following analysis of the excreta and tissues only
    about 5% of the administered dose was accounted for as unchanged
    propargite or the primary metabolites, indicating that the primary
    metabolites are further degraded (Sullivan, 1968).

    The oral administration of a single close of 271 mg/kg benzene ring
    labelled 140 propargite to rats was followed by fast excretion of the
    radiocarbon. Within 72 hours postdosage, 47% of the administered dose
    was eliminated via the urine. 32% via the faeces. The total carcass
    contained approximately 90% of the administered radioactivity.
    Identified metabolites excreted with the rat urine and faeces were
    tert-butylpyrocatechol and glycol ether (Ryer and Sullivan, 1969a)

    In cows treated with a single oral close of 4 mg/kg b.w. combined
    non-radioactive and 14C labelled propargite a similar excretion
    pattern was found. 54% of the administered dose was eliminated with
    the urine, 17% with the faeces. Approximately 0.3% was found in the
    milk. Identified metabolites were tert-butylpyrocatcohol, glycol
    ether and tertbutylphenol (Ryer and Sullivan, 1969b).

    In a feeding study, dairy cows were maintained on a diet containing
    14C-labelled and unlabelled propargite at dosage levels of 3 and 20
    ppm for 12 consecutive days. Peak urinary excretion observed at the
    seventh test day reached values of 4 and 23 mg/kg respectively for the
    3 and 20 ppm dietary level; peak faecal excretion was approximately 1
    and 4 mg/kg. Maximum milk residue values reached on the fourth test
    day were 0.02 and 0.06 mg/kg at the 3 and 20 ppm dose levels
    respectively. Residues in selected tissues ranged from 0.02 to about
    1.3 mg/kg (Kennedy et al., 1970).

    Similar results were obtained after daily administration of a diet
    containing 50 and 100 ppm propargite to lactating cows for a period of
    27 days (Smith and Roger, 1975).

    Pigs were maintained on a diet containing propargite at dosage levels
    of 20 and 100 ppm for 30 days. Residues in kidney and liver were below
    the detection limit of 0.1 mg/kg at both feeding levels and residues
    in muscle and fat ranged from below 0.1 to about 2 mg/kg (Ladd et al.,
    1974).

    Residues studies in hens that were treated with 3, 10 and 30 ppm 14C
    propargite in their diet for 30 days showed residue levels in eggs
    from 0.13, 0.49 and 0-145 g/kg respectively at the 3, 10 and 30 ppm
    dose levels. Residues in muscle ranged from 2-12 g/kg, liver 18-174 
    g/kg kidney 2-25 g/kg and fat 7-116 g/kg depending on exposure
    level (Jenkins et al., 1972).

    After continuous exposure to a concentration of 0.025 mg/l 14C
    propargite in water for 35 days tissue residues in edible portions of
    fishes were about 2 mg/kg. After transfer to uncontaminated water 70%
    of the radioactivity present in the edible tissues was eliminated
    within 14 days (Sleight III, 1972),

    The in vivo metabolism studies in several animal species confirmed
    the rapid degradation of propargite already shown in in vitro
    experiments. The metabolic reactions are hydrolysis of the parent
    ester followed by other cleavage. The formed products are polar
    alcoholic and phenolic compounds which can rapidly be excreted or
    further metabolized and incorporated into natural tissue constituents
    by biochemical reactions which are well documented in the literature.

    See also the section "Fate of residues", "In animals".

    TOXICOLOGICAL STUDIES

    Special study on teratogenicity

    Female rats were orally dosed with 0, 50 and 100 mg/kg from day 6
    through 15 of gestation. The treatment had no effect on maternal body
    weight, mortality or fertility. No reproductive adverse effects were

    found with respect to implantation and resorption sites. Embryonic and
    foetal development was not affected by the treatment
    (Haley et al., 1972).

    Special study on reproduction

    Rat

    See "Long term study".

    Special study on carcinogenicity

    Rat

    See "Long term study".

    Dog

    See "Short term study".

    Acute toxicity

    Species      Sex      Route       LD50             References
                                      mg/kg
                                                                        
    Rat          M, F     oral        approx. 2200     Carson, 1963

    Rabbit       M, F     dermal      approx. 3200     Weir, 1967
                                                                        

    Rat

    Groups of 5 male and 5 female rats were treated for 90 days with
    amounts of propargite in their diet to provide daily intakes of 10,
    20, 40, 100 and 200 mg/kg b.w. corresponding to dietary levels in
    adult animals of 200, 400, 800, 2000 and 4000 ppm respectively. The
    control group existed of 15 male and 15 female rats. Treatment with
    2000 and 4000 ppm caused a dose-related growth retardation and
    reduction of food intake. Haematological examinations and clinical
    chemistry tests revealed no abnormalities. At 2000 and 4000 ppm the
    relative liver weights were increased, the relative kidney weights

    were increased only in the 4000 ppm groups. Gross and microscopic
    examinations of tissues disclosed no treatment-related pathological
    alterations (Carson, 1964).

    Dog

    Groups of 3 male and 3 female dogs were maintained on a diet
    containing propargite at dose levels of 0 and 2000 to 2500 ppm
    (increase of dosage after 3 weeks) for 90 days. The treatment did not
    affect appearance, behaviour, results of haematological. and clinical
    chemistry tests and urinalyses. In most treated dogs reduced food
    consumption and body weight loss and an increase of relative liver and
    kidney weights were observed, No compound-related alterations were
    found macroscopically. Histopathological examinations revealed an
    increased amount of pigment in the liver reticuloendothelial cells and
    increased haemosiderosis of the spleen (Holsing, 1968).

    Groups of 8 dogs were fed a diet containing propargite at 100, 300 and
    900 ppm for 24 months. The control group consisted of 12 animals. The
    treatment had no effect on growth rate, results of clinical laboratory
    studies, urinalyses and organ weights. Gross and microscopic
    examination did not reveal abnormal pathological findings. No tumours
    were found (Osert 1966).

    Long term Study

    Rat

    Groups, each comprising 25 male and 25 female rats were fed dietary
    levels of propargite to provide daily intakes of 5, 15 and 45 mg/kg
    b.w. corresponding to adult levels of 100, 300 and 900 ppm for a
    period of 24 months. The control group consisted of 37 animals of each
    sex. After 26 test weeks without noticeable evidence of a
    treatment-related effect, a supplementary study was started with a
    control-and a test group comprising 25 male and 25 female rats
    receiving 100 mg/kg b.w. corresponding to 2000 ppm for 78 weeks. Rats
    that died during the study and those sacrificed after 104 and 78 weeks
    were examined grossly and microscopically. The treatment had no effect
    on appearance, behaviour, growth rate and mortality at the dietary
    levels up to and including 900 ppm. At the 2000 ppm level at the end
    of the study there was a reduction of food consumption and also a
    reduction of the body weight gain of about 30%; mortality of the male
    rats increased to 32% compared to 7% of the corresponding control.
    Haematological examinations and clinical laboratory studies did not
    reveal abnormal findings. Absolute and relative liver and kidney
    weights of the animals treated with dietary levels of 100, 300 and 900
    ppm which died or were sacrificed after 104 weeks showed inconsistent
    variations without any dose-relationship. At 2000 ppm an increase of
    the relative liver and kidney weights of about 30%. were observed.
    Gross autopsy findings in 1 male (of 25) and 7 females (of 23) in the
    2000 ppm group were enlarged and/or dark red lymph nodes which in some
    cases were involved in abdominal masses. In the corresponding control
    group 2 male rats of 29 animals showed this alteration. No

    dose-dependent increase of the frequency of this lymph node alteration
    was found at the 100, 300 and 900 ppm levels. A variety of benign and
    malignant tumours was observed in the control and treated groups. No
    dose-relationship of the frequency of tumours was found. Four sarcomas
    were found in rats sacrificed after 78 weeks ingestion of 2000 ppm,
    whereas in the corresponding control group no sarcomas were seen
    (Oser, 1966).

    Additionally a 3-generation reproductive was included in the 2-year
    feeding experiment with 20 pairs of male and female rats from the
    control and 100 ppm test groups. Dosage was raised to 300 ppm in the
    F2 pups at the time of weaning. The treatment revealed no abnormal
    findings (Oser, 1966).

    COMMENTS

    Propargite is readily absorbed from the gastrointestinal tract and is
    excreted rapidly as metabolites which are formed mainly by hydrolysis
    of the sulphite ester.

    After feeding a diet containing 20 ppm of propargite the residues in
    milk or in tissues were of the order of 0.1 mg/kg.

    The compound is not teratogenic in the rat.

    In a 3-generation reproductive study no adverse effects were revealed
    at concentrations up to 300 ppm. This concentration is therefore
    regarded as a no-effect level.

    In a 2-year feeding study with up to 900 ppm in dogs which included
    extensive laboratory and histological investigations, no adverse
    effects were noted. A 2-year feeding study in rats up to 2000 ppm
    showed appreciable but not dose-related variations in the relative
    liver and kidney weights in all treated groups. However, no major
    adverse effects were seen. Owing to a poor survival rate and the
    termination of the study with the high dose animals after 78 weeks,
    the finding that the tumour incidence was not elevated is of limited
    value. This study was not considered to fulfil the criteria for an
    acceptable lone-term study. Therefore a safety factor of 200 was used.

    Propargite is structurally related to Aramite, a compound which is
    suspected of being a carcinogen. Although there are no indications
    that propargite acts similarly, the need for satisfactory
    carcinogenicity studies was expressed.

    TOXICOLOGICAL EVALUATION

    Level causing no toxicological effect

         Rat: 300 mg/kg in the diet, equivalent to 15 mg/kg bw
         Dog: 900 mg/kg in the diet, equivalent to 22 mg/kg bw

    ESTIMATE OF TEMPORARY ACCEPTABLE DAILY INTAKE FOR HUMANS

    0-0.08 mg/kg bw

    RESIDUES IN FOOD AND THEIR EVALUATION

    USE PATTERN

    Propargite is an acaracide said to be effective on a variety of mites
    on food crops and ornamentals. Table 1 shows the use patterns
    registered in the U.S.A. Information has been received that the
    product is also used in Italy, Australia, New Zealand, South Africa,
    Argentina, Mexico, and France. The government of the Netherlands has
    informed the Meeting that the compound was used until 1976, at which
    time its use was discontinued. A country statement was received from
    New Zealand regarding uses and tolerances. The uses permitted in these
    countries generally parallel those shown in Table 1. Significant
    exceptions are included in the footnotes.

    RESIDUES RESULTING FROM SUPERVISED TRIALS

    A submission to the Joint Meeting contained data from supervised
    trails on twenty-six crops (Uniroyal, 1977). Most of the trials were
    conducted in the U.S.A. A country statement was received from New
    Zealand with data on peaches. Analyses in all U.S. trials, the
    procedure described under "Methods of residue analysis" (PAM II,
    1973). Analyses of untreated controls (crop blanks) were reported in
    each experiment, along with the recovery of propargite from fortified
    controls. Controls were generally reported as 0 and recoveries were
    adequate. A brief discussion of the residue finding for each crop
    follows. Data are summarized in tabular form when feasible.

    The use patterns employed in Mexico and France on apples, peaches,
    plums and citrus differed significantly from the other countries. In
    the absence of residue data reflecting good agricultural practice in
    those countries, it was not possible to predict residue levels. The
    recommended DIRLs for apples, peaches, plums and citrus therefore are
    based on the national use patterns which can be related to supervised
    residue trails.

    Alfalfa

    There are no national tolerances or registrations for propargite use
    on alfalfa. However, the submission to the Meeting contained some
    residue data on alfalfa hay, fresh forage and trash. Single and
    multiple applications were made at 1.4 to 4.7 kg a.i./ha. Residues on
    fresh forage ranged 0.0 to 328 mg/kg at 28 and 0 day intervals from
    treatment, respectively. Residues on hay and trash ranged from 2.6 to
    100 mg/kg with intervals from treatment of 22 to 52 days. With a 28
    day pre-harvest interval, MRLs of 50 and 75 mg/kg on fresh alfalfa and
    alfalfa hay, respectively, would be adequate.


        TABLE 1. Registered use patterns for propargite (USA)
                                                                                                              
                                  Application           No. of        Pre-harvest
    Crop           Formulation    rate, a.i.            treatments    Interval (days)         Notes
                                                                                                              

    Almond         30% WP         0.03-0.05%(4)         2             28(5)                   low volume
                   68.1% EC       2.5-3.4 kg/ha         1             post-harvest            aerial
                                                                                              application
                                                                                              only
    Apples         30% WP         0.04-0.05(1)(6)       3             7(2)(7)(12)
    Apricots       30% WP         0.05%(4)              2             14(5)                   low volume
                   68.1% EC       1.7-2.5 kg/ha         2             post-harvest            aerial
                                                                                              application
                                                                                              only
    Cranberries    68.1% EC       1.6 kg/ha             1             14
    Beans          75% EC         2.8 hg/ha(4)          2             7(fresh)(5)
                                                                      28 (dry)

    Corn           75% EC         1.9 kg/ha             1             30
    (field)
    Cotton         75% EC         0.85-1.9 kg/ha        3             before bolls open
    Figs           30% WP         0.03-0.05%(3)(4)(11)  2             14
    Grapes         30% WP         1.7-3.0 kg/ha         2             21
                   4% Dust        0.2 kg/ha             2             14
    Grapefruit,    75% EC         0.025-0.05(4)(8)      2             7 (5)
    oranges
    Lemons         30% WP         0.05% (8)             2             7
    Hops           68.1% EC       1.7 kg/ha(4)          2             14 (5)
                   30% WP         1.7 kg/ha             2             14
    Mint           68.1% EC       1.7-2.5 kg/ha         2             14
    Nectarines     30% WP         0.05% (4)             2             14 (5)
    Peaches        30% WP         0.04-0.05%(4)(8)      2             14(5)(10)(13)
    Peanuts        30% WP         1.0-1.7 kg/ha         2             14
    Pears          30% WP         0.04-0.05%(8)
    Plums          30% WP         0.04-0.05(4)(8)       2             14(5)(10)
    Potatoes       75% EC         1.4-2.4 kg/ha         2             14
                   68.1% EC       1.7-2.5 kg/ha         2             14

    TABLE 1. (Continued)
                                                                                                              
                                  Application           No. of        Pre-harvest
    Crop           Formulation    rate, a.i.            treatments    Interval (days)         Notes
                                                                                                              
    Sorghum        75% EC         1.5-1.9 kg/ha         1             30 silage
                                                                      60 grain
    Strawberries   30% WP         1.7-3.4 kg/ha(9)      3             3
                   4% Dust        1.8 kg/ha             3             3
    Walnuts        68.1% EC       0.03-0.05% (4)        2             14 (5)
                                                                                                              

    (1) France 0.12, Italy 0.06%
    (2) France 21, Italy 15, New Zealand 14
    (3) France 0.6-0.9 kg/ha
    (4) Italy 0.06%
    (5) Italy 21
    (6) Mexico 0.08-0.12%
    (7) Mexico 28
    (8) Mexico 0.12%
    (9) East U.S.A. 0.84 kg/ha
    (10) Argentina 21
    (11) Argentina 0.05%
    (12) South Africa 14
    (13) South Africa 21

    

    Almonds

    Field trials were conducted in California: 63 samples of nut meats
    were anlayzed. Residues on the nut meats from two applications of 0.03
    and 0.06% sprays were < 0.1 mg/kg at post-treatment intervals of 21
    to 28 days.

    Residues on almond hulls from treatment with 0.05% spray (30% WP)
    followed by 3.4 kg a.i./ha (68.1% EC) ranged from 5.2 to 31 mg/kg with
    pre-harvest intervals of 28-35 days. Under good agricultural practice,
    residues are not likely to exceed 55 mg/kg.

    Apples

    Field trials were conducted in nine U.S.A. states, South Africa and
    Australia, some 452 samples being analysed. The residue data are
    summarized in Table 2. All controls were reported zero. Residues from
    applications of up to 0.06% spray after 7 days were less than 3 mg/kg.

    Residue data indicate that residues remain associated with the apple
    pomace and are not destroyed in drying. Residues in the juice were
    barely detectable (ca. 0.02 mg/kg) while residues in the wet and dried
    pomace were 16-21 mg/kg and 56-80 mg/kg, respectively. Thus, residues
    concentrate by factors of 15-22 in the manufacture of dried pomace
    from treated apples (Uniroyal, 1972), An MRL of 80 mg/kg in dried
    apple pomace is therefore appropriate.

        TABLE 2. Range of residues in apples, mg/kg.
                                                                                   
    Application rate,        Interval (days, last treatment to harvest)

    %                     0-1         6-7        14         21         28
                                                                                   

    0.03                  0.1-3.1     0.6-1.8    0.2-1.0    0.2-0.7    0.2-0.9
    0.06                  0.3-6.3     0.5-1.6    0.3-2.4    0.5-1.1    0.2-0.6
                                                                                   
    
    Apricots, peaches and plums

    Field trials were conducted in California, Connecticut, Georgia, North
    and South Carolina, Maryland, Michigan, Pennsylvania, Washington, New
    York and New Zealand. Some 385 test samples of fresh fruit and 65
    controls were anlaysed from one and two applications at four dosage
    rates, including the maximum and twice the maximum label rates (Table
    1). The residue data are summarized in Table 3. Only one residue on
    peaches was greater than 7 mg/kg at 14 days after treatment at the
    maximum rate. Residues will not exceed 7 mg/kg from sprays up to
    0.06%, provided that treatments are not made within 14 days of
    harvest.

    A study was conducted on plums (fresh prunes) using a standard
    commercial drying process to determine residues on dried prunes. The
    average residue value for the dried fruit was ca. 20% of the average
    value for the fresh fruit. Thus no additional MRL is needed for the
    dried fruit.


        TABLE 3. Range of residues on apricots, peaches and plums, mg/kg

                                                                                 

    Application rate.       Interval (days, last treatment to harvest)

    %                   0-1            6-7            13-14          21-23
                                                                                 

    0.03                0.4-12         0.2-7.0        0.4-10.0       0.3-5.0
    0.05                0.7-6.7        2.6-14.0       0.6-5.6        0.0-1.7
    0.06                1.3-17.0       1.3-8.7        0.2-5.5        0.3-9.3
    0.10                1.6-27.0       0.3-8.4        0.8-11.0       0.8-3.5
                                                                                 

    
    Beans

    Field trials were conducted in the states of Washington, California
    and Idaho on snap beans, succulent lima beans and dry beans. 52
    analyses were reported. Single and multiple applications were made at
    the maximum and at twice the maximum label rate (Table 1), by aerial
    and ground application. The residues are summarized in Table 4 for
    fresh and dry beans, 7 and 28 days after the last treatment,
    respectively. No residue data were submitted for bean vines; however
    there is a restriction against the feeding or foraging of treated bean
    vines. The only other feed item, cannery waste, would consist of cull
    beans with some bean vines and pods present as a result of mechanical
    harvesting. Residue levels would not be likely to exceed 20 mg/kg on
    cannery waste.

        TABLE 4. Range of residues in beans, mg/kg
                                                                                
                                            Application rate, kg a.i./ha
                                             2.8                  5.6
                                                                                
    Fresh (7 days after last treatment)      <0.2-15              <0.2-12
    Dry (29 days after last treatment        <0.1-0.1             <0.1-0.24
                                                                                

    
    Maize

    Residue data for maize were made available from five U.S.A. sites, two
    in California and one each in Colorado, Texas and Nebraska. Following
    applications at the maximum and twice the maximum label rates (Table
    1), silage stage maize sampled 28-35 days after application contained
    maximum residues of 2.4 and 18 mg/kg, respectively; maize stover,
    sampled after 47-105 days, contained maximum residues of 4 and 11
    mg/kg, respectively. Interpolation of the 2X data shows that MRLs on
    maize forage and fodder of 10 mg/kg are appropriate.

    No detectable residues (< 0.1 mg/kg) were found on either the grain
    or ears of maize sampled 60-105 days after the above applications. No
    data on grain reflecting a 30 day pre-harvest interval were submitted.
    However, since propargite does not translocate to any extent, residues
    on grain are not expected to exceed 0.1 mg/kg.

    Cotton

    Five field studies from locations in California, Arkansas and
    Mississippi were reported. The studies reflect treatment at the
    maximum and twice the maximum label rate (Table 1). Analyses were
    performed on 96 samples of cottonseed and processed products, hulls,
    oil, meal and soapstock. All values on cottonseed were reported as
    < 0.1 mg/kg. All samples of meal and soapstock contained
    < 0.05 mg/kg as did all but on refined oil sample which contained a
    level of 0.1 mg/kg after treatment at an excessive rate. Almost all of
    the hull samples had low but detectable residues, 0.03-0.06 mg/kg.
    Thus, an MRL of 0.1 mg/kg is appropriate for cottonseed. There is a
    restriction in the U.S.A. against feeding treated foliage or cotton
    trash to livestock.

    Cranberries

    Seven studies were reported from Massachusetts, with a total of 36
    analyses. The studies reflect applications at 1.68 kg a.i./ha (4 by
    ground and 3 by air) with one study at 3.36 kg a.i./ha. Several of the
    studies show decline rates (at 7, 14 and 21 days). The residue
    declines rapidly between 0 and 7 days and then shows little further
    decline from 7 to 21 days. At the recommended rate (Table 1), residues
    are not likely to exceed 10 mg/kg. Residues are summarized in Table 5.

        TABLE 5. Range of residues in cranberries, mg/kg
                                                                                
    Application rate,        Interval (days, last treatment to harvest)
    kg a.i./ha               0            7            14           21
                                                                                
    1.68                     2.2-11       <0.1-1.9     <0.1-7.1     0.1-1.0
    3.36                                               3.3-14.9
                                                                                
    
    Figs

    The residue data for figs consists of four studies made in California,
    including two decline studies. Various applications were made
    including the maximum and twice the maximum label rate (Table 15).
    Residues on fresh figs are summarized in Table 6. While the data are
    limited, it is not likely that residues will exceed 3 mg/kg at 14 days
    after treatment.

        TABLE 6. Residues on figs, mg/kg

                                                                                             

    Application rate,           Interval (days, last treatment to harvest)
    kg a.i./ha                  0-1         7           13-14        21          28
                                                                                             

    1.27                        3.3         1.9         0.8          0.45
    2.02                        1.6-2.8     1.0-1.4     0.2-1.4                  0.3-0.6
    4.04                        2.5-5.3     2.2-3.2     0.7-4.2
                                                                                             

    
    Grapefruit, oranges and lemons

    Field trials were conducted in Texas, Florida and California. Some 281
    harvest samples were analyzed. One and two applications were made at
    the recommended and twice the recommended rates (Table 1). The results
    are summarized in Table 6. For applications up to 0.06% spray with a
    7 day interval, 5 mg/kg would not be exceeded.

    Washed oranges bearing residues of 1.9 mg/kg were processed to dried
    pulp by a procedure simulating the commercial process. The residue in
    the dried pulp was 15.5 mg/kg. The residue in the dried pulp is about
    eight times that on the whole fruit, so 40 mg/kg is an appropriate
    MRL.

    TABLE 6. Range of residues in grapefruit, oranges and
    lemons, mg/kg
                                                                       

    Application rate,   Interval (days, last treatment to harvest)
    %                   0           7          14          28
                                                                       

    0.03                0.3-0.5     0.2-0.8    0.2-0.3     0.9-1.0
    0.05                1.7-3.6     0.2-4.8    1.1-2.1     0.6-3.1
    0.06                1.0-1.4     0.9-2.5    0.0-0.9     0.6-1.2
    0.10                1.0-5.1     0.8-7.2    1.2-3.2     1.2-2.9
                                                                       

    Grapes

    Residue trials were conducted in Washington and California, with
    analyses of 254 samples of grapes. A wide range of experimental
    conditions in the various field tests and the resulting variation in
    residues preclude a tabular summary of the data. No residues exceeded
    10 mg/kg from the maximum recommended rate with a 21 day interval
    after treatment.

    A residue concentration factor of 2.5 was observed in the commercial
    production of raisins from fresh grapes. Thus a 25 mg/kg MRL for
    raisins would be appropriate. The data showed a concentration of
    residues on dried grape pomace to 4 times that found on fresh grapes,
    therefore, 40 mg/kg would be appropriate for grape pomace.

    Hops

    Eight field trials were conducted in the State of Washington. Residues
    on green hops resulting from three applications at the maximum and
    twice the maximum label rate (Table 1) are summarized in Table 7.
    Residues on green hops from good agricultural practices are not likely
    to exceed 15 mg/kg. Residues on dried hops ranged from 11 to 30 mg/kg
    14 days after treatment. A 30 mg/kg MRL would be appropriate for dried
    hops since residues from two applications will probably be somewhat
    lower than those noted above.

        TABLE 7. Range of residues on green hops, mg/kg
                                                                                

    Application rate,             Interval (days last treatment to harvest)
    kg a.i./ha                    0         6-7       13-14     20
                                                                                

    1.7                           24-50     5-17      6-15      2-6
    3.4                           36-92     24-66     11-43     6-24
                                                                                

    
    Mint

    Field studies were conducted in Washington, Oregon and Idaho. A total
    of 89 analyses were made on fresh hay, spent hay and mint oil, 
    including controls. In four studies, two applications were made at
    rates of 2.5 and 5 kg a.i./ha resulting in maximum residues of 19 and
    50 mg/kg respectively, 15-17 days after treatment. Three residue
    decline studies were also submitted. Samples were taken 0, 1, 2 and 4
    weeks after a single aerial application at 1 and 2 times the maximum
    label rate (Table 1). From a decline curve based on these data,
    residues resulting from the recommended use are ca. 50 mg/kg on fresh
    mint hay.

    Five samples of fresh mint hay bearing residues of 8.7-50 mg/kg were
    fractionated by steam distillation and the resulting mint oil and
    spent hay contained residues of 1.6-7.9 mg/kg and 12-97 mg/kg
    respectively. Residues in mint oil are not likely to exceed those on
    fresh mint hay and there is a restriction against feeding spent mint
    hay to livestock.

    Nectarines

    Seven trials were conducted at locations in California and
    Pennsylvania. One or two applications were made at one and two times
    the maximum label rate (Table 1). The residue data are summarized in
    Table 8. Residues were no higher than 3-4 mg/kg at the prescribed
    pre-harvest interval. However, extrapolation of data from peaches,
    apricots, and plums would indicate that a 7 mg/kg MRL would be
    appropriate.

        TABLE 8. Range of residues in nectarines, mg/kg

                                                                               

    Application rate,           Interval (days, last treatment to harvest)
    %                           0            6-7        13-15       20-21
                                                                               

    0.05                        0.66-7.3     0.24-3.1   0.44-3.4    0.39-1.3
    0.10                        1-3-10.5     0.34-5.1   0.91-3.4    0.41-1.5
                                                                               

    
    Peanuts

    Residue studies were conducted in Georgia, Florida, North Carolina,
    Oklahoma, Mississippi and Arkansas. Two applications were made in all
    but four decline studies on peanut vines, where only one application
    was made. Dosages ranged from 0.6 times to twice the maximum
    recommended rate (Table 1). Six of the studies reflect a 14 day
    preharvest interval, but in the other ten studies intervals were from
    19 to 66 days.

    Peanut kernels

    All residue values were reported as < 0.1 mg/kg. Since no detectable
    residues were found in peanuts, no MRLs are needed for peanut
    by-products, meal, oil and soapstock.

    Peanut hulls

    Residues were < 0.1 mg/kg in five of seven studies. Residues of
    0.14 mg/kg, 0.3 mg/kg and 1.2 mg/kg were found after applications at

    twice, 6 times and 1.2 times the recommended rates respectively, in
    the other two studies.

    Peanut vines and hay

    Residues were less than 10 mg/kg 14 days after application at the
    maximum rate. The data indicate that residues decline rapidly from a
    maximum of 38 mg/kg at 0 days to 3.6 mg/kg at 14 days.

    Pears

    Four field studies were conducted in California, Pennsylvania,
    Michigan and Washington, one and two applications were made with 0.03
    and 0.06% sprays. The residue data are summarized in Table 9. All
    residues were less than 3 mg/kg, 14 days after treatment.

        TABLE 9. Range of residues in pears, mg/kg

                                                                                    

    Application rate,        Interval (days, last treatment to harvest)
    %                        0              7             14            21
                                                                                    

    0.03                     0.6-1.6        0.3-1.2       0-2.7         0.1-2.4
    0.06                     2.2-4.1        0.9-2.6       0.3-2.2       0.1-1.7
                                                                                    

    
    Potatoes

    Seven residue studies were made available, four from Washington and
    one each from Idaho, Vermont and Illinois. After two applications at
    rates of 1.5 to 4.5 kg a.i./ha, all residues were less than the limit
    of detection of the method (0.1 mg/kg) 14 days after treatment.

    Sorghum

    Field studies were conducted in Texas, Nebraska and Iowa on grain
    sorghum. Applications were made at the maximum and twice the maximum
    recommended rates (Table 1). Samples of grain and forage or fodder
    were harvested at 28, 30, 44 and 50 days after application. Residues
    in forage ranged from < 0.1 to 4.1 mg/kg. Residues in forage and
    fodder are not likely to exceed 10 mg/kg 30 days after treatment.

    Residue levels in grain ranged from < 0.1 to 2.4 mg/kg 60 days or
    more after treatment. Thus an MRL of 5 mg/kg with a 60 day interval
    after treatment is appropriate for sorghum grain.

    Strawberries

    Field trials were conducted in California, Louisiana and Florida.
    Strawberries treated with two formulations in California, reflecting
    three applications at the maximum recommended rate (Table 1) had
    residues ranging from 0.19 to 4.0 mg/kg for 3 days after treatment.
    Residues from applications of 0.84 and 1.7 kg/ha in Louisiana and
    Florida are summarized in Table 10. Under good agricultural practice,
    residues are not likely to exceed 7 mg/kg.

    TABLE 10. Range of residues in stramberries, mg/kg

                                                                           

    Application rate        Interval (days, last treatment to harvest)
    kg a.i./ha              0                3                 7
                                                                           

    1.7                     0.9-2.0          0.3-3.8           0.2-0.7
    3.4                     1.4-4.1          0.7-9.2           0.4-1.1
                                                                           

    Sugar beets

    There are no national tolerances or registrations for propargite on
    sugar beets; however, this use is pending in the U.S.A. The submission
    to the Meeting therefore contained some residue data on sugar beet
    tops, roots and by-products. Sugar beet root samples from Idaho,
    Washington and California reflecting two treatments at 2.8 and 5.6 kg
    a.i./ha and a 21 day interval from treatment# showed residues ranging
    from 0.05 to 0.23 ind/kg and 0.13 to 0.28 mg/kg respectively.

    In a residue decline study, on sugar beet tops, a single application
    at 2.8 kg a.i./ha yielded residues of 40-114 mg/kg at 0 days.
    20-80 mg/kg at 14-17 days and 2.4-34 mg/kg at 27-28 days. Adiitional
    data for tops representing two ground treatments at 2.8 and 5.6
    kg a.i./ha show residues ranging from 11-24 mg/kg and 19-59 mg/kg
    respectively (21 day interval).

    In order to obtain data on processing fractions, sugar beet roots
    bearing 0.1 mg/kg residues were processed to wet and dry pulp,
    molasses and sugar. Propargite residues in wet pulp, molasses and
    sugar were less than or equal to 0.1 mg/kg. The data for dry pulp show
    a maximum residue concentration factor of 5, with residues from
    0.1-0.5 mg/kg.

    Tea

    There are no national tolerances or registrations for propargite in
    tea, however, a tolerance for this use is pending in the U.S.A. The
    submission to the Meeting contained some residue data on dried tea
    leaves, both green and black. The data are summarized in Table 11.

        TABLE 11. Range of residues in tea, mg/kg

                                                                                  

    Application rate,           Interval (days, last treatment to harvest)

    kg a.i./ha                  0              7            14           28
                                                                                  

    0.31                                       <0.1-0.3     <0.1-0.2
    0.75                        48-178         1.1-4.2      <0.1-0.2     <0.1
                                                                                  

    
    Walnuts

    Six field trials were conducted at locations in California. Both
    30% WP and 75% EC formulations were applied at the maximum recommended
    rate (Table 1). No residues were detected in any of the walnut meat
    samples 45 to 48 days after treatment. Although the interval is
    greater than that recommended (14 days), since propargite is
    non-systemic, any residues found on nut meats would be expected to
    arise as a result of contamination in de-hulling and de-shelling
    processes. Under good agricultural practice, an MRL of 0.1 mg/kg (at
    or about limit of determination) would be appropriate. There is a
    restriction against grazing or feeding livestock on cover crops growm
    in treated orchards, therefore no feed items are involved in this use.

    Meat, milk, poultry and eggs

    Propargite is used on a number of crops which yield by-products used
    commercially for animal feeds. Primary sources would be dried citrus
    pulp, sorghum grain, forage and fodder and maize forage and fodder.
    Some additional contribution could occur from dried pomace, almond
    hulls and dried grape pomace. Per this reason, some animal feeding
    studies were submitted. These are also referred to in the section
    "Biochemical aspects", where references are given.

    In one study, cattle were fed at levels of 3 and 20 ppm in the total
    dry diet for 12 days. Maximum residues in milk (whole milk basis) were
    0.059-0.067 mg/kg. The latter is equivalent to 1.7 mg/kg on the fat
    basis. Maximum residues in tissues were as follows: liver, 1.3 mg/kg,
    kidney, 0.27 mg/kg, fat, 0.21 mg/kg and muscle, 0.18 mg/kg.

    In a second study, cows received 0, 50 and 100 ppm in the diet for 27
    days. Analysis of milk showed all samples at both feeding levels to be
    < 0.08 mg/kg. Residues ranged up to 1.6 mg/kg on a fat basis.
    Residues in muscle, kidney and liver from both feeding levels were
    40.03 mg/kg (limit of determination). Residues in fat ranged from 0.32
    to 0.42 mg/kg at the 10 and 100 ppm feeding levels, respectively.

    Poultry were fed 3, 10 or 30 ppm in the diet for 30 days (3 chickens
    in each group). Eggs were sampled daily and the animals were
    sacrificed 24. hours after treatment. Maximum levels In eggs were
    0.013 mg/kg at the 3 PPM level, 0.043 mg/kg at the 10 ppm feeding
    level, and 0.106 mi/kg at the 30 ppm level. Liver tissue had the
    highest residue levels ranging from 0.047 to 0.089 mg/kg at the 10
    diet level and from 0.17 to 0.18 mg/kg at the 30 diet level.

    Hogs were fed 20 and 100 ppm in the total diet. Two hogs at each level
    and one control were maintained for 30 days. No residues
    (< 0.1 mg/kg) were found in liver or kidney. No residues were found
    in muscle at the 20 ppm level but up to 0.23 mg/kg at the 100 ppm
    intake. In fat, residues up to 0.18 and 0.2 mg/kg were found at the 20
    and 100 ppm intakes, respectively.

    The studies show that residues may transfer to meat, milk, poultry and
    eggs. A mixed ration for cattle could consist of 15% dried apple
    pomace, 15% dried citrus pulp and 70% sorghum grain, forage and fodder
    or maize forage and fodder. This diet could theoretically contain
    propargite residues of ca. 25 mg/kg.

    A maximum possible intake of 10 mg/kg could result from the hogging
    down of peanut fields and other swine feed items such as maize grain
    and cooked potatoes.

    Poultry feed items, sorghum grain, grape pomace, maize grain and
    cooked potatoes, could contribute ca. 8 mg/kg propargite to the diet.

    Residues are unlikely to exceed 2 mg/kg in milk fat and 0.1 mg/kg in
    the meat, meat by-product, and fat of cattle, goats, hogs, horses,
    poultry and sheep.

    FATE OF RESIDUES

    In animals

    The available data on metabolism by animals are more conclusive than
    those on metabolism by animals are move conclusive than those on
    metabolism by plants. See also "Biochemical aspects."

    Propargite -14C feeding tests have been conducted on a number of
    animals including the rat, cow, pig and chicken. Additional
    information on degradation was available from in vitro experiments
    with buffered liver homogenates.

    A general metabolism scheme has been proposed for animals, part of
    which has been verified experimentally, and part of which is based on
    analogy with biochemical reactions reported in the literature.
    Identification of some metabolites was by TLC comparison with prepared
    standards. In other cases less positive identification was made by
    partition co-effecients (p values) and solvent extraction scheme. In
    cow liver the bulk of the 14C activity was identified only as polar
    metabolites.

    The experiments apparently were carried out over a number of years,
    the studies in some animals being repeated with refinements in
    analytical techniques. None of the work on propargite submitted to the
    Meeting has been published. Certain general conclusions appear
    justified. (a) Propargite is metabolized in animals to polar compounds
    which are excreted, principally in the urine. (b) There is not a
    pronounced tendency to storage or accumulation in the body, but the
    compound is not completely metabolized because the parent compound was
    the principal residue in the milk of cows, was tentatively identified
    as a portion of the 14C activity in animal fat, and was found in
    excreta. (c) The parent compound is detected in the liver only for
    short periods after ingestion. d) The primary hydrolysis products, the
    glycol ether and propargyl alcohol, are further degraded. (e) Some
    polar metabolites are in conjugated forms.

    A list of the metabolits and the sites in which they were reported is
    given in Table 12. The sequence of the metabolic scheme is not
    definitely known.

    TABLE 12. Propargite metabolites
                                                                           
    Compound                        Found in
                                                                           
    Parent                          Cow: butter fat, body fat (1)
                                    Rat: liver (1)
                                    liver homogenate (1)

    Glycol ether                    Cow: urine, faeces, milk (2)
                                    Rat: faeces, liver (1)
                                    liver homogenate (1)

    Propargyl alcohol               liver homogenate (1)

    Butylphenol                     Cow: urine (2)
                                    Rat: liver (1)
                                    liver homogenate (1)

    Butylcatechol                   Cow: urine (2)
                                    Rat: urine, faeces (2)

    Cyclohexandiol                  urine (2)

    "Polar metabolites"             Rat: liver (2)
                                    Cow: liver (2)
                                                                           

    (1) Identified by GLC or TLC

    (2) Tentatively characterized by solvent
        fractionation scheme, p values, literature analogies.

    In plants

    Propargite is generally considered to be "non-systemic" by mode of
    miticidal action. According to information made available to the
    Meeting aged residues are primarily surface residues of the parent
    compound (Uniroyall 1977). Residue decline was attributed to
    volatilization of the parent compound and hydrolysis to propargyl
    alcohol and the "glycol ether",
    2-(p-tert-butylphenoxycyclohexanol). The two hydrolysis products
    have not been detected in samples by chemical analysis at a detection
    level of 0.1 mg/kg. In experiments on bean plants to investigate
    possible photolytic degradation, the same two compounds could not be
    detected. It has been suggested that if the glycol ether and propargyl
    alcohol are intermediates in the degradation scheme, their presence is
    fleeting because of their volatility.

    Other evidence cited in the manufacturer's submission on the behavior
    of propargite in plants was: (a) comparison of surface and pulp
    analysis of apples showed no absorption (of parent); (b) mites
    confined to upper leaf surfaces were not affected by sprays on the
    lower surfaces (c) there was no effect on mites of an adjacent leaf
    when on leaf of a bean plant was treated; (d) volatility losses of the
    parent compound under field conditions have been correlated with model
    laboratory experiments (loss from aluminum foil).

    The above experiments partially support the idea that propargite is
    not translocated in plants and that the residue of concern is
    propargite per se. However, much of the evidence is indirect, and it
    would be desirable to have conventional metabolism studies on some
    representative crops, using 35S and/or 14C, to confirm the fate of
    propargite in plants.

    In soil

    Only a summary was made available (Uniroyall 1977). The half-life in a
    variety of soils was said to range from 2 to 18 weeks. Leaching is
    negligible. Laboratory and field studies have shown that propargite is
    hydrolysed in soil. The major soil degradation product found was the
    glycol ether.

    Summary, metabolism

    The available metabolism studies do not firmly identify the residue
    components in plants or animals. However, there is sufficient
    information to indicate a probable metabolic scheme. It is fairly
    certain that the primary metabolites are the hydrolysis products
    tert-butylphenoxycyclohexanol and propargyl alcohol. It is probable
    that further breakdown to butylphenol and cyclohexanediol occurs. If
    correlations are to be made between metabolic schemes and toxic
    potential for propargite and aramite, it should be noted that both
    compounds hydrolyze at the sulfite ester, aramite yielding

    2-chloroethanol and propargite yielding propargyl alcohol. Whether any
    further confirmatory studies are needed would depend on the toxic
    potential of the postulated fragments.

    EVIDENCE OF RESIDUES IN FOOD IN COMMERCE OR AT CONSUMPTION

    Propargite is detected in the multi-residue screening procedure
    employed by the Canadian Department of Health and Welfare, The
    compound is eluted from Florisil in fraction 3 as described in the
    method (15% acetone in hexane). Only 4 positive findings of propargite
    were reported in the Canadian surveillance programs (as of 1977). The
    highest residue was found in a nectarine sample at 0.57 mg/kg (Health
    Protection Branch, 1977),

    The U.S. Food and Drug Administration multi-residue method has not
    been validated for propargite. The specific GLC/FPD analytical method
    has not been applied in the U.S. surveillance programme. Therefore
    propargite has not been reported in foods in channels of commerce in
    the U.S.A. No reports from other governments have been received on
    occurrence in commerce.

    There were no data available on reduction of residues through washing,
    cooking or processing. The principal exposure through ingestion would
    be from fruits eaten raw and unpeeled.

    METHODS OF RESIDUE ANALYSIS

    The early residue data on propargite (mid 1960s) were obtained by gas
    chromatography with flame ionization or microcouclometric (SO2)
    detection. Some difficulties were experienced by government
    laboratories in validation studies on the method at that time were
    because the clean-up and extraction procedures were unsatisfactory.
    Through a series of modifications, a basic procedure using gas
    chromatography with flame photometric detection (FPB) has evolved
    which is satisfactory for a wide variety of fruits, vegetables, and
    animal tissues (Devine and Sisken, 1972).

    In the basic method, residues are extracted with 1:1 hexane and
    isopropanol, followed by an aqueous NaCl wash and Florisil column
    chromatography. For oily or waxy samples an optional step is included
    in which the residues are partitioned into nitromethane. Other
    modifications are prescribed for certain crops. The method has been
    validated in U.S. government laboratories on milk, apples and animal
    tissues (PAM III, 1973). Depending on the substrate, the limit of
    determination is about 0.05 to 0.2 mg/kg.

    A similar GC-FPD method for propargite residue in citrus has been
    reported by Westlake et al, (1971).

    Propargite is not known to be recovered through the U.S. Food and Drug
    Administration multiresidue procedure. Information received from


        NATIONAL TOLERANCES REPORTED TO THE MEETING
                                                                                                     

                                                 Tolerance, mg/kg

    Commodity                USA                 Canada              New Zealand    Australia
    
                                                                                                     

    Almonds                  0.1
    Almonds, hulls           55
    Apples                   3                   3                   3                 3
    Apples, pomace, dried    80
    Apricots                 7                                                         3
    Bananas                                                                            3
    Beans, dry               0.2
    Beans, succulent         20
    Citrus, dried pulp       40
    Corn, fodder             10
    Corn, forage             10
    Corn, grain              0.1
    Cottonseed               0.1                                                       3
    Cranberries              10
    Eggs                     0.1
    Figs                     3
    Grapefruit               5                   5
    Grapes                   10                  7
    Grapes, pomace           40
    Hops                     15                                                        3
    Hops, dried              30                  30
    Lemons                   5                   5
    Milk                     0.08

    NATIONAL TOLERANCES REPORTED TO THE MEETING (Continued)
                                                                                                     

                                                 Tolerance, mg/kg
    Commodity                USA                 Canada              New Zealand    Australia

                                                                                                     
  
    Milk, fat                2
    Mint                     50
    Nectarines               4                                                         3
    Oranges                  5                   5
    Passion fruit                                                                      3
    Peaches                  7                   7                                     3
    Peanuts                  0.1
    Peanuts, forage          10
    Peanuts, hay             10
    Peanuts, hulls           10                                      3
    Pears                    3                   3                                     3
    Plums (prunes)           7                   3                                     3
    Potatoes                 0.1
    Raisins                  25
    Sorghum, fodder          10
    Sorghum, forage          10
    Sorghum, grain           10
    Strawberries             7                   7                   3
    Walnuts                  0.1
    Meat, meat
    by-products and fat
    of cattle, goats, hogs,
    horses, poultry and
    sheep                    0.1

                                                                                                     

    

    Canadian authorities is that it is recovered through their
    multiresidue procedure. It is eluted from Florisil in fraction 3 of
    the Canadian procedure (15% acetone/hexane).

    APPRAISAL

    Propargite is an acaricide which has been used on a wide variety of
    food crops and ornamentals since its introduction in 1967. Available
    information indicates that the product is used in Australia, New
    Zealand, Argentina, Mexico, France, South Africa, Italy and the U.S.A.

    The primary manufacturer has submitted a report on supervised trials
    on 26 crops, all of which were conducted in the U.S.A. Limited residue
    data were received from New Zealand on peaches). U.S.A., Canada, New
    Zealand and Australia have set national tolerances (MRLs) for
    propargite.

    Propargite is non-syrtemic by mode of action against mites, and data
    indicate that residues which do occur are surface residues. Residues
    on the harvested commodities are primarily propargite per se. No
    significant metabolites or alteration products have been reported on
    harvested crops. However, much of the evidence regarding the fate of
    propargite on plants is indirect. It would be desirable to have 35S
    or 14C radiotracer studies to confirm the degradation pathways in
    plants.

    Radioactively labelled propargite (14C) has been used in some animal
    experiments, including studies on the rat, cow and chicken. Techniques
    used to fractionate and identify the activity were not as definitive
    as would be desired, but it is fairly certain that propargite is
    hydrolysed in the body to tert-butylphenoxyoyclohexanol and
    propargyl alcohol. It is probable that there is further degradation to
    butylphenol and cyclohexanediol and excretion as conjugates in the
    urine. However, some residues of unchanged parent compound do occur in
    milk, body fat and briefly in liver. If any correlations are to be
    made between the metabolism of propargite and the related compound
    aramite, it may be significant to compare the toxic potential of the
    hydrolysis product propargyl alcohol with that of the corresponding
    hydrolysis product of eremite, -chloroethanol.

    An analytical method suitable for regulatory purposes is available. It
    is a gas chromatographic method (published) with flame photometric
    detection that has been validated in government laboratories.
    Propargite is also measured by the multi-residue method employed in
    the Canadian surveillance programme. It has not been studies in the
    U.S. Food and Drug Administration's multi-residue method.

    RECOMMENDATIONS

    Temporary maximum residue limits for propargite on the following
    commodities are recommended.

    Commodity           Limit mg/kg         Pre-harvest intervals on which
                                            recommendations are based     
                                           (days)
    Apple pomace        80
    Alfalfa hay         75                  28
    Almond hulls        55                  28
    Alfalfa, fresh      50                  28
    Mint hay            50                  14
    Dried citrus pulp   40
    Grape pomace        40
    Dried hops          30
    Raisins             25
    Beans (in pod)      20                  7
    Corn fodder
    and forage          10                  30
    Cranberries         10                  14
    Grapes              10                  14-21
    Peanut hay
    and forage          10                  14
    Sorghum fodder
    and forage          10                  30 (if silaged)
    Apricots, peaches,
    plums, nectarines   7                   14
    Strawberries        7                   3
    Citrus              5                   7
    Sorghum grain       5                   60
    Apples, pears       3
    Pigs                3                   14
    Milk (fat)          2
    Beans, dry          0.2                 28
    Almonds             0.1*                28
    Cottonseed          0.1*                before bolls open
    Eggs                0.1
    Fat of poultry      0.1
    Fat of meat         0.1
    Maize (kernels)     0.1*                30
    Milk, whole         0.1
    Peanuts (kernels)   0.1*                14
    Potatoes            0.1*                14
    Walnuts             0.1*                14

    * At or about the limit of determination

    FURTHER WORK OR INFORMATION

    REQUIRED (Before July 1981)

    1.   A carcinogenic study

    DESIRABLE

    1.   Mutagenicity studies
    2.   Observations in humans
    3.   Data from supervised trials in countries other than the USA
    4.   Information on the occurrence of residues on commodities in
         commerce
    5.   Confirmation of the postulated degradation pathway in plants
         using radio-labelled propargite.

    REFERENCES

    Carson S. (1963)  Acute Oral LD50 in Rats. Unpublished report from
    Food and Drug Research Lab., submitted by Uniroyal Chemcial, Inc.

    Carson S. (1963) Subacute Feeding Studies with D-014 in Rats.
    Unpublished report from Food and Drug Research Lab., submitted by
    Uniroyal Chemical, Inc.

    Haley, G., Kennedy, G.L. and Keplinger, M.L. (1972) Teratogenic Study
    with Omite in Albino Rats. Unpublished report from Bio-Test
    Laboratories, submitted by Uniroyal Chemical.

    Health Protection Branch (1977) Personal communication, Canada Bu.
    Chem. Safety, Health Protection Branch to FAO Panel of Experts, 1977.

    Holsing, G.C. (1968) 13-Week Dietary Feeding - Dogs. Unpublished
    report from Hazleton Laboratories, Inc., submitted by Uniroyal
    Chemical.

    Jenkins, D.H., Kennedy, G. and Keplinger, M.L. (1972) Study with Omite
    in White Leghorn Chickens. Unpublished report from Industrial Bio-Test
    Laboratories, submitted by Uniroyal Chemical.

    Kennedy, G., Jenkins, D.H. and Keplinger, M.L. (1970) Metabolism of
    14C-Omite in the Cow. Unpublished report from Industrial Bio-Test
    Laboratories, submitted by Uniroyal Chemical.

    Ladd, R., Jenkins, D.H. and Keplinger, M.L. (1974) Tissue Residue
    Study with Omite in Crossbred Swine. Unpublished report from Bio-Test
    Laboratories, submitted by Uniroyal Chemical.

    Oser, B.L. (1966) Chronic (2-Year) Feeding Studies with D-014 in Rate
    and Dogs. Unpublished report from Food and Drug Research Lab.9
    submitted by Uniroyal Chemical.

    PAM II Pesticide Analytical Manual, Vol. II, revised (1973); U.S.
    Department of Health, Education and Welfare, Food and Drug
    Administration.

    Ryer, F.H. and Sullivany J.B. (1969) Rachiotracer Drug Metabolism
    Study with Omite 14C. Unpublished report from Hazleton Laboratories,
    Inc., submitted by Uniroyal Chemical.

    Ryer, F.H. and Sullivany J.B. (1969b) The Fate of Omite 14C in the
    Cow. Unpublished report from Hazleton Laboratoriesy Inc., submitted by
    Uniroyal Chemical.

    Sleight III, B.H. and Maceky K.J. (1972) 14C Omite Fish Accumulation.
    Unpublished report from Bionomics, Inc., submitted by Uniroyal
    Chemical.

    Smith, K.S. and Roger, J.C. (1975) Omite Milk and Tissue Residue Study
    in Dairy Cows: Unpublished report from Cannon Laboratories, submitted
    by Uniroyal Chemical.

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    See Also:
       Toxicological Abbreviations
       Propargite (Pesticide residues in food: 1978 evaluations)
       Propargite (Pesticide residues in food: 1979 evaluations)
       Propargite (Pesticide residues in food: 1980 evaluations)
       Propargite (Pesticide residues in food: 1982 evaluations)
       Propargite (JMPR Evaluations 1999 Part II Toxicological)