FAO/PL:1967/M/11/1 WHO/Food Add./68.30 1967 EVALUATIONS OF SOME PESTICIDE RESIDUES IN FOOD THE MONOGRAPHS The content of this document is the result of the deliberations of the Joint Meeting of the FAO Working Party of Experts and the WHO Expert Committee on Pesticide Residues, which met in Rome, 4 - 11 December, 1967. (FAO/WHO, 1968) FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS WORLD HEALTH ORGANIZATION Rome, 1968 CARBON DISULFIDE This pesticide was evaluated for acceptable daily intake by the 1965 Joint Meeting of the FAO Committee on Pesticides in Agriculture and the WHO Expert Committee on Pesticide Residues (FAO/WHO, 1965). Since no additional information on the toxicology of this compound has become available, the following monograph addendum is confined to evaluation for tolerances and a review of methods of analysis. EVALUATION FOR TOLERANCES USE PATTERN Post-harvest treatments Carbon disulfide is used as a fumigant to control insects in stored bulk grain, bagged grain, dry beans and peas, oilcake and potatoes. It is generally used with carbon tetrachloride (with or without ethylene dibromide) and in poured on the surface of the grain or in a shallow dish on top of the grain in silos and bins. The application rates are variable depending upon the type of commodity, storage facilities and the temperature. RESIDUES RESULTING FROM SUPERVISED TRIALS In wheat, 5.8 ppm carbon disulfide was found 5 days after fumigation treated at the rate of 275 ml/1000 kg, with a carbon disulfide-carbon tetrachloride mixture (20 : 80 per cent by vol) and 13.0 ppm after treatment at the rate of 825 ml/1000 kg with the same mixture (Keppel and Munsey, 1957). In another experiment the whole wheat, before cleaning, contained 1.1 and 1.9 ppm carbon disulfide (5 days after fumigation at the two rates mentioned above) and 0.5 and 0.7 respectively after cleaning and tempering (untreated wheat, before cleaning contained 0.6 ppm and after cleaning 0.4 ppm). A residue study in commercially fumigated grain (33 samples of wheat, 13 samples of corn, 9 of rough rice, 5 of oats and 4 of grain sorghum) showed maximum residues in wheat, presumably sampled before any turning, of 3.7 ppm of carbon disulfide 5 months after fumigation. Maximum residues in corn, rough rice, oats and grain sorghum were all lower than those in wheat (Lynn and Vorhes, 1957). FATE OF RESIDUES In storage and processing Milling Straight flour, shorts and bran milled from wheat containing 5.8 ppm carbon disulfide, contained 6.0, 5.9 and 8.3 ppm carbon disulfide respectively, and from wheat containing 13.0 ppm, 0.7, 3.4 and 1.6 ppm respectively. A part of the study mentioned above indicates that in practice the loss of residues during the cleaning and tempering process before milling will range upwards to 70 per cent at high initial residue levels. Only traces of the residue will carry through into the flour. In flour, shorts, bran and germ (untreated samples contained 0.4, 0.4, 0.4 and 0.3 ppm carbon disulfide respectively), milled from wheat containing 1.1 ppm residues of 0.5, 0.5, 0.5 and 0.5 ppm respectively wore found, and from wheat containing 1.9 ppm, 0.5, 0.4, 0.5 and 0.4 ppm respectively (Lynn and Vorhes, 1957). Baking Carbon disulfide added at the rate of 10.6 and 7.0 ppm to commercial bakers' flour and bread bases respectively, approximately 10 times the maximum levels found in flour after normal fumigation, resulted in residues in the baked bread of 0.5 ppm (Munsey et al., 1957). Cooking Quick-cooking rolled oats, treated with 10.4 ppm carbon disulfide, after cooking for one minute, resulted in average residues of 1.2 ppm, thus loss in cooking was 88 per cent. It is unlikely that any measurable amount of carbon disulfide would be left in cooked commercial rolled oats which had hem treated at normal dosages (Munsey et al., 1957). Comments From the available data it appears that initial residues are fairly high and that these residues decrease up to 70 per cent during cleaning and processing. During baking and cooking much of the remaining residue disappears. METHODS OF RESIDUE ANALYSIS Martens and Nangniot (1963) refer to a polarographic method originally developed by Zuman. The method is suitable for determination of carbon disulfide residues in foodstuffs up to a concentration of 2 × 10-4M. Berck developed a gas chromatographic method suitable for determination of carbon disulfide alone and a multidetection method for microgram amounts of 34 fumigant gases (Berck, 1965). Bielorai and Alumot (1966) developed an electron-capture gas chromatographic method for determination of residual fumigants in cereal grains. NATIONAL TOLERANCES Country Tolerance, ppm Crop Bulgaria 0 ppm Cereals Brazil exempt Cereals India exempt Cereals Netherlands 0 ppm Grains U.S.A. (established) exempt Barley, oats, corn popcorn, rice, rye, sorghum (milo), wheat. RECOMMENDATIONS FOR TOLERANCES None recommended because of lack of recommendation for an acceptable daily intake (FAO/WHO, 1965). FURTHER WORK Further work required before acceptable daily intakes and tolerances can be recommended. It the use of carbon disulfide for the fumigation of certain types of food proved to be essential, then research would have to be carried out : 1. on the nature and quantity of the residues present in the treated food. 2. on the long-term effects in at least two animal species of carbon disulfide and the products to which it may give rise by reaction with the protein constituents of food. REFERENCES PERTINENT TO EVALUATION FOR TOLERANCES Berck, B. (1965) Determination of fumigant gases by gas chromatography. J. Agr. Food Chem. 13: 373-377. Bielorai, R., Alumot, E. (1966) Determination of residues of a fumigant nature in cereal grain by electron-capture gas chromatography. Jour. Agr. Food Chem. 14: 622-625. FAO/WHO. (1965) Evaluation of the hazards to consumers resulting from the use of fumigants in the protection of food. FAO Mtg. Rpt. PL/1964/10/2; WHO/Food Add./28.65. Keppell, G.E., Munsey, V.E. (1957) A second adaptation of Lowen's dithiocarbamate method. Jour. Assoc. Off. Agr. Chem. 40 : 171-174. Lynn, G.E., Vorhes, F.A. (1957) Symposium: Residues in food and foods resulting from fumigation of grains with the commoner liquid formulations of carbon disulfide, carbon tetrachloride, ethylene dichloride and ethylene dibromide. Jour. Assoc. Off. Agr. Chem. 40: 163-209. Martens, P.H., Nangniot, P. (1963) La détermination de résidus d'insecticides et de fongicides par la méthode polarographique. Residue Rev. 2: 26-50. Munsey, V.E., Mills, P.A., Klein, A.K. (1957) Effect of cooking on fumigant residues. Jour. Assoc. Off. Agr. Chem. 40: 201-202.
See Also: Toxicological Abbreviations Carbon disulfide (EHC 10, 1979) Carbon disulfide (ICSC) Carbon disulfide (PIM 102) Carbon disulfide (FAO Meeting Report PL/1965/10/2) Carbon disulfide (FAO/PL:1968/M/9/1) Carbon disulfide (WHO Pesticide Residues Series 1) Carbon Disulfide (CICADS 46, 2002)