MANCOZEB         JMPR 1974


         Mancozeb was considered by the Joint Meetings in 1967 and 1970
    (FAO/WHO 1968, 1971). No tolerances were recommended in 1967, and a
    single temporary tolerance of 1 mg/kg in potatoes was recommended in
    1970. Since it was recognized that mancozeb is used in several
    countries on a wide variety of crops the Meeting concluded that the
    following information was required before further tolerances could be

         "Further study on the biotransformation of the compound in plants
    to determine the chemical nature of the residues, followed by
    appropriate toxicological studies. The extensive residue data already
    submitted need to be validated by the diethylamine method and by
    measuring the level of ethylenethiourea. (Some of these data are known
    to be available but were not submitted in time for detailed scrutiny
    by the Meeting)".

         In response to these requirements the following information was

    Ethylenethiourea (ETU) content in the technical and formulated

         Bontoyan and Looker (1973a,b) studied the initial
    ethylenethiourea content of various ethylenebisdithiocarbamate (EBDC)
    products. The average ETU content in 76 different lots of mancozeb
    manufactured at 6 different locations throughout the world was 0.07%.

         Povlsen et al. (1974) analysed 9 samples of mancozeb, alone or as
    a mixed product with dinocap. The ETU content (expressed as % w/w of
    the declared EBDC content) varied between <0.01 and 0.04%.

         Bontoyan and Looker (1973a) studied the effect of storage
    conditions on the ETU content of formulated EBDC products. Samples of
    mancozeb, maneb, and zineb were stored for 39 days at 48°C and a
    relative humidity of 80%, thus simulating storage conditions which may
    occur in normal practice during summer. The initial ETU content in
    mancozeb formulations was about 0.02%, and in "maneb 80%" 0.05 -
    1.26%. After 39 days of storage the ETU content in the formulated EBDC
    products increased; in mancozeb to 0.13%. in "maneb 80%" preparation
    to 0.58 - 14.04%, and in "zineb 80%" to 3.48 - 10.44%. The rate of ETU
    formation was greatest in the maneb products; the zineb formulations
    were degraded less rapidly and at a more uniform rate and the mancozeb
    products were degraded slowly and formed little ETU.

    TABLE 1  Residues of CS2 and ETU resulting from supervised trials with mancozeb


                                     Application*                     Pre-harvest interval in days
    Crop and                 No      rate             0/1        0/1         7          7         14         14         21         21
    Country                          kg a.i./ha       CS2+       ETU        CS2        ETU        CS2        ETU        CS2        ETU

    USA (1972)               9       4.2                         <0.01-                <0.01-                <0.01-                <0.01
                                                                 0.02                  0.02                  0.02

                             11      4.8                                                                     <0.01-                <0.01

                             6       4.8                                                                     <0.01                 <0.01

                             4       6.4                                                                     <0.01                 <0.01

    Banana (pulp)
    Honduras (1972)          1       6.75             0.1        <0.01      0.1        <0.01      0.1        <0.01
                                                      1.1        <0.01      0.9        <0.01      0.9        <0.01

                             1       6.75             0.2        <0.01      0.2        <0.01      n.d.       0.01
                                                      0.1        <0.01      0.2        <0.01      n.d.       <0.01

                             1       10.5             0.1        <0.01      0.1        <0.01      0.1        <0.01
                                                      1.6        <0.01      3.1        0.02-      3.1        0.03-
                                                                                       0.05                  0.04

                             1       10.5             0.1        <0.01      0.2        <0.01      0.2        <0.01
                                                      0.2        <0.01      0.2        <0.01      0.1        <0.01

                             1       10.5             n.d.       0.01       n.d.       <0.01      n.d.       <0.01
                                                      0.3        <0.01      1.2        <0.01      1.4        <0.01

                             1       10.5             n.d.       <0.01      0.1        <0.01      0.1        <0.01
                                                      n.d.       <0.01      n.d.       <0.01      n.d.       <0.01

    TABLE 1  (Cont'd.)


                                     Application*                     Pre-harvest interval in days
    Crop and                 No      rate             0/1        0/1         7          7         14         14         21         21
    Country                          kg a.i./ha       CS2+       ETU        CS2        ETU        CS2        ETU        CS2        ETU

                             1       1.4              n.d.       <0.01      n.d.       <0.01      n.d.       0.01
                                                      0.2        <0.01      0.8        <0.01      0.4        <0.01

    USA (1972)               1       1.6              3.7-       0.02-      2.0-       <0.01-     1.4-       n.d.       n.d.       n.d.
                                                      5.7        0.06       4.4        <0.02      1.8                   0.1

                             1       1.6                                    1.0-       0.01-      0.7-       n.d.       0.1-       n.d.
                                                                            2.8        0.02       0.8                   0.8

    USA (1972)               1       1.2                         0.05-                 <0.01                 n.d.
                                                                 0.14                  0.02

    USA (1972)               1       1.6                         0.02-                 0.03-                 <0.01
                                                                 0.03                  0.05                  0.02

    USA (1972)               13      1.6                         n.d.                  n.d.                  n.d.
                             13      2.4                         n.d.                  n.d.                  n.d.

    *  Formulation used in all cases was 80% wettable powder.
    +  All figures for CS2 and ETU expressed in mg/kg.



         Data on mancozeb residues in various crops (analysed as CS2) and
    on potatoes (analysed as ethylenediamine) were considered by the 1967
    and 1970 Joint Meetings respectively. More recently, residue data were
    obtained from apples, bananas, celery, spinach, tomatoes and maize
    (sweet corn) on levels of the parent compound, including some of the
    intermediate degradation products, by the CS2 method, and on levels
    of ETU. The figures are expressed in mg/kg CS2 and mg/kg ETU in Table


    General Comments

         Lyman (1971), Lyman and Lacoste (1974) reviewed the fate of
    mancozeb in plants, animals, water and soil. They demonstrated that
    breakdown in plants and animals is similar, and proceeds through a
    series of intermediates, the structures of most of which have been
    elucidated. The final products are metallic cations (Mn2+ and Zn2+),
    inorganic materials such as elemental sulphur, thiosulphate and
    sulphate ions and, via a series of organic intermediates,
    ethylenediamine. Earlier findings with respect to these intermediates
    were confirmed.

    In plants

         Several recent studies illustrate the degradation pattern of
    ethylenebisdithiocarbamates in plants, e.g. Czeglédi-Janke (1967);
    Vekstejn and Klisenko (1970); Engst et al. (1968, 1969); Vonk et al.
    (1970, 1974a, 1974b). A recent review of these studies by Engst and
    Schnaak (1974) gives the degradation pathway shown in Figure 1.

         According to the few results available the degradation products
    of EBDC compounds (mainly ETU and EBIS) vary in the extent of their
    production in different plants and under different conditions.

         According to Engst et al. (1968), EBIS and ETU residues increased
    from about 0.05 mg/kg immediately after application to about 0.1 mg/kg
    at the sixth day and then decreased rapidly up to the tenth day.
    Klisenko and Vekstejn (1971) obtained similar degradation curves with
    zineb in beets showing first an increase of EBIS and ETU then a rapid
    degradation. Yip et al. (1971), however, found 0.45 and 0.15 mg/kg ETU
    in maneb treated lettuce and cabbage respectively immediately after
    treatment, which was completely degraded within 7 days.

    FIGURE 1

         Vonk and Sijpesteijn (1970) studied the fate of the main
    metabolites of EBDC's in the green parts of cucumber plants after
    application of 14C-ethylene labelled nabam to the leaves. They found
    the following distribution of radioactivity in water extracts from
    cucumber leaves after 0.7 and 19 days. The compounds were separated by

    TABLE 2  Fate of nabam in cucumbers

                                       % of total detected radioactivity
                                            after interval (days)
    Compound                           0           7          19

    ethylene thiourea (ETU)            31          11         3.5

    2-imidazoline                      12          14         19

    ethyleneurea (EU)                  4           17         21

    polar material remaining
    at origin                          22          39.5       40

    other unidentified compounds       31          18         16.5

         From this and other experiments the conclusion could be drawn
    that from solutions of EBDC's in which ETU and EBIS (DIDT) are formed
    only ETU is taken up in the plants. This compound is converted almost
    quantitatively into a mixture of ethylene urea (EU) and 2-imidazoline.

         In a study with radio-labelled mancozeb (3H, 14C or 35S) on
    leafy plants such as sugar beets, lettuce or turnips, applied at
    exaggerated rates to facilitate identification of metabolites, the
    following intermediates could be detected 13 days after application by
    using reverse isotope dilution techniques (Lyman 1971).


    Compound                                          Percentage of 3H

    mancozeb                                                   9

    ethylene thiourea (ETU)                                    6

    ethyleneurea (EU)                                         17

    ethylenediamine                                           11

    2-imidazoline                                              8

    N-formylethylenediamine                                    8

    (DIDT or EBIS)                                             7

    (Jaffe's base)                                            4

                                       Total                  62


         The quantitative figures are an example and do not necessarily
    indicate a typical distribution of percentages of metabolites present
    in a residue.

    Uptake and translocation of ETU in plants

         It was shown by Sato and Tomiziwa (1960) and Vonk and Sijpesteijn
    (1970, 1971) that ETU can be taken up by the roots and translocated
    through the plant. In another study by Lyman and Lacoste (1974), 14C
    ETU was applied either to the leaves or to the soil around young
    potato or tomato plants. The tomato plants had 1 - 3 fruits at the
    time of application. Only small amounts of radioactivity moved from
    the site of application to the fruits or to other parts of the plant
    (Table 3).

    TABLE 3  Translocation of radioactivity from 14C ETU

                                    14C activity expressed as ETU
                                   (mg/kg) after indicated interval
                             in potatoes                    in tomatoes
    Application      tuber     foliage    roots           fruit      foliage
                     90 days   90 days    60 days         28 days    28 days

    Leaves           0.14      24         0.05            0.8        64

    Soil             n.d.*     0.84       n.d.            0.4        6

    *  n.d. no detectable radioactivity = (<0.0001 mg/kg ETU)

    In water

         Exposure of mancozeb to spray tank conditions did not produce
    significant ETU build-up during normal residence times. Analysis of a
    spray tank slurry of "mancozeb 80%", containing 0.1% a.i. showed an
    ETU content of 2.08 mg/kg after 1 minute increasing to 3.62 mg/kg
    after 4 hours.

         Lyman and Lacoste (1974) studied the hydrolysis of 14C labelled
    mancozeb in water at PH 5, 7 and 9. Sterile water was used to
    distinguish chemical from biological degradation. Suspensions of 20
    ppm mancozeb were agitated for 28 days at 25°C in amber bottles (to
    avoid photodecomposition). Samples taken at selected intervals were
    analysed by TLC. Two different chromatographic systems were used to
    provide confirmation of the identity of the spots. The radioactive
    zones were detected by autoradiography and were subsequently
    quantitated by liquid scintillation counting. The nonradioactive
    standards were located on the TLC plates by UV light or with a spray

         It was shown that mancozeb is not stable in water and that the
    half-life in the pH 5 - 9 range is less than 1 day (Table 4).

    TABLE 4  Hydrolysis of 14C labelled mancozeb


                         % of total 14C found as parent mancozeb
                         after indicated interval

              hours                  days
    pH        2      24     48       3      6      10     14     21     28

    5         62.3   27.2   11.5     15.2   13.6   10.6   4.0    6.4    6.1

    7         25.6   13.6   14.8     16.9   2.3    10.0   8.2    7.0    4.2

    9         0

         The nature and quantity of the degradation products are
    pH-dependent. ETU and ethyleneurea are found within the range studied.

         Cruickshank and Jarrow (1973) showed that aqueous solutions of
    ETU exposed to UV light (above 285 mm) undergo a very slow photolysis:
    the process is markedly accelerated by photosensitisers. When kept in
    the dark ETU is stable to hydrolysis over the pH range 5 - 9 at 90°C.
    These results were confirmed by Bontoyan and Looker (1973b).

         Ross and Crosby (1973) observed that photosensitisers present in
    agricultural drainage water will catalyze the photodegradation of ETU
    (Table 5). The degradation does not occur in the absence of UV light.
    Laboratory experiments carried out by Lyman and Lacoste (1974) showed
    similar results to those of Ross and Crosby.

    TABLE 5  Effect of UV irradiation on degradation of ETU in
             agricultural drainage water


    Duration (hours) and      % of initial 14C found as ETU*
      type of exposure        in sterile water    in non-sterile water

        5      UV             75                  92

        24     UV             none                none

        48     UV             none                none

        48     dark           104                 101

    *  confirmed by reverse isotope dilution

    In soil

         A recent study of EBDC compounds in soil by Hylin (1973)
    illustrates the degradation pattern discussed previously. Kaufman
    (1973) studied the fate of 14C labelled ETU in two types of soil
    (Hagerstown silty clay loam and lakeland sandy loam) both sterile and
    non-sterile. Essentially all of the ETU was converted to
    2-imidazolidone within two days in the Hagerstown silty clay loam
    treated with 2 and 20 mg/kg ETU and within 8 days in this soil treated
    with 200 mg/kg ETU. A slower but steady conversion of ETU to
    2-imidazolidone occurred in sterile (autoclaved) soil. In the
    non-sterile Hagerstown silty clay loam further degradation occurred
    rapidly. Within 7 days after treatment with 2, 20 and 200 mg/kg ETU
    43.4, 8.9 and 0.9% respectively of the initial 14C was evolved at
    14CO2 was evolved from the sterile, autoclaved soil.

         In the lakeland sandy loam a similar but somewhat slower
    degradation of ETU was observed. Besides 14CO2, two products were
    identified by co-chromatography as 2,4-imidazolidinedione and
    1-(2'-imidazolin-2'-yl)-2-imidazolinethione (Jaffe's base). A third
    was tentatively identified as a subsequent degradation product of the
    latter compound, and a fourth was unidentified.

         Lyman and Lacoste (1974) studied the fate of ETU applied at
    exaggerated rates on a sandy soil under field conditions. The high
    dosage rates applied provided considerably more ETU than could be
    expected from the application of mancozeb at recommended dosages. The
    experiment illustrates that ETU when exposed to field conditions
    degrades rapidly in or on the top one cm of a relatively inert

    TABLE 6.  Decline of ETU in sand


    Dosage rate         ETU (mg/kg) at interval (days) after spraying
       kg/ha             0           1           3           7

       0.77             8.2         0.35        0.02        0.02

       0.77             9.8         1.53        0.01        n.d.*

       0.036            0.03        n.d.        n.d.        n.d.

    *  n.d.: No detectable residues (<0.01 mg/kg).

         In a study in which 10 and 20 mg/kg 14C labelled mancozeb and
    10 mg/kg 14C labelled ETU were applied to Hagerstown salt loam soil
    it was demonstrated that both mancozeb and ETU are readily degraded by
    soil micro-organisms to the point of releasing their ethylene carbons
    as CO2. The 14CO2 released was trapped in sodium hydroxide and
    measured by liquid scintillation to determine the loss of the best

         The experiments with each compound were done in both sterile and
    non-sterile soils. No evolution of 14CO2 was observed from sterile
    soil, but in non-sterile soil both mancozeb and ETU are rapidly
    degraded to 14CO2. The half-life for ETU at the 10 mg/kg level is
    about 22 days and that for 20 mg/kg mancozeb about 50 days. The
    experiment with 10 mg/kg mancozeb was continued for 170 days; the
    half-life was about 90 days.

    Leaching experiments

         Lyman and Lacoste (1974) studied the leaching of 14C mancozeb
    and its degradation products in 5 different types of soil. The organic
    matter in these soils ranged from 0.4 to 15% and the pH from 4.7 to

         An aqueous slurry of 14C labelled mancozeb was mixed with soil
    which was then applied to the top of a 45 cm high column with a
    diameter of 12.3 cm. The dosage applied was equivalent to a field
    application of 8 kg mancozeb a.i./ha i.e. about 15.6 mg of mancozeb
    80% to each column. Once a week for 9 weeks 2.5 cm of water was
    applied to the top of each column. Radioactivity in the water emerging
    from the column was determined by liquid scintillation counting. After
    9 weeks the columns were cut into 2.5 cm sections and a sample from
    each section was combusted to 14CO2, which was trapped and measured
    by liquid scintillation counting. No radioactivity leached through
    four of the 5 soils, and leaching beyond the top 2.5 cm was slight. In
    cecil clay, however, 2 - 5% of the activity was leached from the
    column and 37 - 47% was found below the top 2.5 cm. This soil was a
    kaolinite clay containing 32% sand, 54% clay, 14% silt and 0.49%
    organic matter. The pH was 4.7. Losses of radioactivity by
    volatilization or by complete metabolism to CO2 were significant in
    all soils except the cecil clay soil.

    Effect of processing and cooking

         Haines and Adler (1973) studied the effect of normal cooking (20
    minute boiling) ETU residues in spinach. Various samples were selected
    from field studies with mancozeb at different intervals (0-14 days)
    after the application of 7 x 1.5 kg "mancozeb 80%"/ha. In cases where
    ETU residues were found in the uncooked samples (0.03 - 0.11 mg/kg) no
    residues were found after cooking (Table 7).

    TABLE 7  Residues of ETU in spinach, before and after cooking

    Interval after                     Residues, mg/kg
    application (days)       uncooked spinach     cooked spinach

                             mancozeb          ETU              ETU

    0                        6.8-8.3         0.9-0.11           n.d.*

    3                        2.6-3.8         0.03-0.03          n.d.

    7                        0.6-1.2         n.d.-n.d.          n.d.

    14                       0.6-0.8         n.d.-n.d.          n.d.

    *  n.d.: <0.01 mg/kg

         These results differ from those obtained by Watts et al. (1974)
    after cooking spinach fortified with mancozeb. They found that ETU was
    formed by cooking, the weight produced being about 20% of the weight
    of mancozeb originally added. The effect on other EBDC compounds was
    similar (Table 8). Newsome and Laver (1973) reported similar results
    after cooking spinach, potatoes and carrots containing residues of
    mancozeb and metiram.

    TABLE 8  ETU produced by cooking vegetables fortified with 10 mg/kg
             of EBDC compounds +

                                        ETU (mg/kg)
               EBDC               Fortified     Fortified      Percentage of
    Crop       compound           after         before         ETU formed by
                                  cooking       cooking        cooking*

    Spinach    maneb              0.16          1.82           16.6
               (Dithane M-45)     0.15          2.17           20.2
               (Manzate 200)      0.11          2.42           23.1
               metiram            0.07          2.72           26.5

    Potato     metiram            0.08          1.43           13.5
               maneb              0.08          1.20           11.2

    Carrot     metiram            0.09          1.42           13.3
               maneb              0.08          1.42           13.4
    +  After Watts et al. (1974).
    *  Weight ETU formed as percentage of weight of mancozeb added.


    Mancozeb and ethylenediamine-yielding metabolites

         A method for the determination of ethylenediamine (EDA) which is
    liberated from known components of residues [mancozeb, free
    ethlylenediamine (EDA), ethyleneurea (EU), ETU, EBIS (DIDT)] was
    presented at the 1970 JMPR by Rohm and Haas. A modified method was
    developed by Newsome (1974). The EDA is isolated, after hydrolysis of
    the residues with acid containing stannous chloride, by ion exchange
    chromatography and quantitated by gas liquid chromatography of its
    bis(triflouroacetate). Overall recoveries at levels of 0.16 - 1.3
    mg/kg parent compound mancozeb were greater than 80% and generally
    more than 95%. The limit of detection in terms of mancozeb is about
    0.1 mg/kg.


         Several methods are available for the determination of ETU
    residues in food, soil and water. The gas-chromatographic methods are
    suitable, or may be adapted, for regulatory purposes (Haines and Adler
    1973, Newsome 1974, Onley and Yip 1971, Nash 1974).

         Blazques (1973) developed a TLC method for the determination of
    ETU in plants, soil and water with a limit of detection of 0.1 mg/kg.
    Merek-Luenyo and Barragan-Allcaide (1974) developed a new TLC method,
    in which ETU is detected by nitrosation and subsequent colour reaction
    with N-(1-naphtyl)-ethylenediamine dihydrochloride. ETU, EBIS and
    ethylene thiuram disulfide appear as purple spots.

         Engst and Schnaak developed a polarographic procedure for the
    determination of ETU in vegetable and animal products. After
    extraction with methanol the interfering substances are separated by
    column and paper chromatography. ETU is converted to the
    nitroso-compound determined by its reduction wave using a cathode ray
    polarograph. The limit of detection is about 0.05 mg/kg ETU.


    a) Mancozeb

         Tolerances are in effect in a number of countries around the
    world. The tolerances are expressed and residues calculated as parent
    compound, as zineb, or as the CS2 moiety.

    b) ETU

         No national tolerances have been established.


         Mancozeb was considered by the 1967 and 1970 Joint Meetings. At
    the 1970 Meeting further data on the biotransformation of the compound
    in plants and animals was requested.

         Several new studies have been carried out which clarify to a
    large extent the metabolic pathway of mancozeb. It has been shown that
    the breakdown of the compound in plants and animals is qualitatively
    similar, and proceeds through a series of intermediates; the
    structures of most of them have been clarified. Several other
    ethylenebisdithiocarbamates (EBDCs) in common use show a similar
    breakdown pattern on plants, leading to several identical

         Information was obtained on the variation in the content of ETU
    in technical mancozeb from several different manufacturers and in
    various formulated products.

         It has been shown that cooking of commodities of plant origin
    containing mancozeb residues produce ETU to an extent corresponding to
    about 25% of the weight of the original residue. Other EBDC compounds
    gave similar results.

         Additional data on the residues of mancozeb and ETU arising from
    treatments according to good agricultural practice were obtained and
    compared with those on zineb and maneb.

         Several new sensitive methods are now available for the
    determination of ethylenethiourea (ETU), the residue intermediate
    which gives most concern. Some of these methods, which allow the
    determination of ETU in plants and in products of animal origin at
    levels of about 0.005 - 0.01 mg/kg, are suitable for regulatory
    purposes. On the other hand, it is recognised that no specific methods
    for determining mancozeb or for distinguishing its residues from those
    of other EBDC compounds are available, and that development of such
    methods in the near future is unlikely. It may therefore be of value,
    in order to detect exaggerated uses of these compounds, to establish
    maximum residue limits on the combined basis of either the
    ethylenediamine or the CS2 moiety of the EBDC molecule, and the ETU
    content. For regulatory purposes the determination of CS2 is more
    convenient but suffers from the disadvantage of not distinguishing
    EBDC residues from those of dimethyldithiocarbamates or thiram, and
    toxicological considerations may make these distinctions important.
    The ethylenediamine method of analysis is more time consuming
    determination but more sensitive and not subject to interference by
    the dimethyldithiocarbamates or thiram. The Meeting therefore
    recommends (1) that residue limits should be based on the
    determination of the ethylenediamine moiety; (2) that the specified
    limit should be for ethylenediamine; (3) that limits for ETU should
    also be observed. Specific limits for ethylenediamine and ETU are


         The following temporary tolerances for ethylenediamine and ETU
    replace the single recommendation for "parent compound or sum of all
    dithiocarbamates present" in potatoes, made in 1970. Neither limit
    should be exceeded in any sample.



                                                        intervals on which
                        ethylenediamine     ETU         recommendations
                           mg/kg            mg/kg       are based (days)

    Potatoes                0.05            0.01*              14

    Apples, pears           2               0.02               14

    Banana pulp             0.05            0.01*               0

    Celery                  2               0.01*              14

    Lettuce                 2               0.01*              21

    Tomatoes                1               0.05                7

    Carrots                 0.2             0.01*              14

    Maize: sweetcorn
    cob and kernel
    (husks removed)         0.2             0.01*               7

    Beans (with pod)        3               0.1                 7 - 10

    *  at or about the limit of determination.



    1.   Residue studies in which both the ethylenediamine moiety and
    ethylenethiourea (ETU) are separately determined.

    2.   Further studies on the fate of residues during the preparation
    and processing of foods with Particular reference to their conversion
    to ETU.


    Benson, W.R., Rose, R.D., Chen, J.-Y.T., Barron, R.P. and Mastbrook,
    D. (1972) Structure of ethylene thiurem monosulfide. J. Ass. Off.
    Analyt. Chem., 55(1):44-46.

    Blazques, C.H., (1973) Residue determination of ethylene thiourea
    (2-imidazolidinethione) from tomato foliage, soil, and water. J. Agr.
    Food. Chem., 21(3):330-332.

    Bontoyan, W.R. and Looker, J.B. (1973a) Degradation of commercial
    ethylene bisdithiocarbamate formulations to ethylenethiourea under
    elevated temperature and humidity. J. Agr. Food Chem., 21(3):338-341.

    Bontoyan, W.R., Looker, J.B. (1973b) Report to the 1973 AOAC Meeting. 
    Washington, D.C.

    Cruickshank, P.A. and Jarrow, H.C. (1973) Ethylenethiourea
    degradation. J. Agr. Food Chem., 21(3):333-335.

    Czeglédi-Jankó, G. (1967) Determination of the degradation products of
    ethylenebis-dithiocarbamates by thin layer chromatography and some
    investigations of their decomposition in vitro. J. Chromat., 31:89-95.

    Dekhuijzen, H.M., Vonk, J.W. and Sijpesteijn, A. Kaars. (1971)
    Terminal residues of dithiocarbamate fungicides. Pesticide Terminal
    Residues Butterworth, London (Suppl. Pure Appl. Chem.) p. 233-242.

    Engst, R. and Schnaak, W. (1967) Untersuchungen zum Metabolismus der
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    See Also:
       Toxicological Abbreviations
       Mancozeb (ICSC)
       Mancozeb (FAO/PL:1967/M/11/1)
       Mancozeb (AGP:1970/M/12/1)
       Mancozeb (Pesticide residues in food: 1993 evaluations Part II Toxicology)