Publications (2)0 Total impact
[show abstract] [hide abstract]
ABSTRACT: A new, simple, and rapid procedure for determining chlorinated pesticide residues in milk is described. The entire acetonitrile extract from milk is passed through a 0.5 g activated charcoal chromatographic column. Chlorinated pesticides adsorbed on the charcoal are eluted with 100 mL acetone-hexane (1 + 1). The eluate is washed with water and 1% sodium carbonate solution, and chlorinated pesticides are extracted with hexane. The extract is concentrated and measured by electron capture gas chromatography. Recoveries from 50 mL milk samples fortified with 0.04-1.6 micrograms of different BHC isomers, 0.05-2 micrograms DDT and its metabolites, and 0.05-0.5 micrograms dieldrin ranged from 86.9 to 103.2%.Journal - Association of Official Analytical Chemists 12/1983; 66(6):1315-8.
Article: Simple analytical method for organophosphorus pesticide determination in unpolished rice, using removal of fats by zinc acetate.[show abstract] [hide abstract]
ABSTRACT: A rapid and simple method is developed for the determination of organophosphorus pesticides in unpolished rice. The new method incorporated acetonitrile-water (1 + 1) extraction, removal of fats by zinc acetate, and further cleanup on an activated charcoal chromatographic column. The higher fatty acids in the extract react rapidly with zinc acetate to form insoluble zinc carboxylates, which precipitate. Additional interferences were cleaned up on an activated charcoal chromatographic column, and organophosphorus pesticides adsorbed on the activated charcoal were eluted with acetone-hexane. Dimethoate is not retained on the activated charcoal and must be extracted with dichloromethane from the first acetonitrile-water eluate. Pesticides are measured by flame photometric gas chromatography. Recoveries from 50 g unpolished rice samples fortified with 5-50 micrograms diazinon, 6-30 micrograms parathion, 8-40 micrograms fenitrothion and IBP, 10-50 micrograms dimethoate and fenthoate, 20-100 micrograms malathion, or 40-200 micrograms EPN ranged from 75.7 to 95.8%.Journal - Association of Official Analytical Chemists 67(4):798-800.