A multiclass, multiresidue analytical method for determining pesticide residues in air

Abstract

A multiresidue method for chlorinated, organophosphate and N-methyl carbamate insecticides has been developed for use in the National Air Monitoring Program. The method involves partitioning and extracting the pesticides from the ethylene glycol trapping solvent with methylene chloride followed by fractionation and cleanup by elution through a silica gel column. The chlorinated compounds are determined by electron capture GC, phosphate compounds by flame photometric GC, and carbamates by electron capture GC after derivatization with pentafluoropropionic anhydride. Recovery data and limits of detectability are presented for 11 chlorinated, 7 phosphate, and 7 carbamate pesticides at high and low levels. It is expected that the method will be applicable to many other compounds not successfully determined by the present analytical procedure, and that it may be adaptable for the analysis of pesticide residues in foods and other environmental samples.

Determination of organochlorine pesticides and metabolites in drinking water, human blood serum, and adipose tissue

“…This procedure is based in part on the methods reported by Enos et al (1967) and Sherma and Shafik (1975).…”

Fate of carbofuran and its metabolites on strawberries in the environment

“…The trifluoroacetate derivatization of the carbofuran and related compounds was based on the method of Shafik et al (1972) as described by Sherma and Shafik (1975) and analyzed by GLC. The 7-phenol was analyzed as the PFB derivative since derivatization with TFA in our laboratory did not result in reproducible results with the desired analytical sensitivity and recovery.…”

Automatic multi-phase sampling device

“…For low level electron capture measurements, and when fractionation of several pesticides is required, the ethyl acetate extract of the XAD-4 resin could be subjected to column chromatography prior to gas chromatographic analysis. The silica gel cleanup/fractionation of Sherma and Shafik (9) has proved to be particularly efficient in this regard in our own work (14).…”