Method Development, Validation, and Analysis of Bifenthrin Residues in Fresh and Dry Cilantro Foliages and Cilantro Seeds Using GC-ECD

摘要

Pesticides of various chemical structures are used worldwide in agriculture industry to attack pests which result in better crops, increased yields and lower input costs. Although these chemicals are considered to he important to agricultural development, there is a growing public concern about the residues of these chemicals on health, environmental contamination, and ecological conditions. Bifenthrin, CAS number 82657-04-3, formula C_(23)H_(22)ClF_3O_2, IUPAC name [2-methyl-(l,1'-biphenyl)-3-yl]-methyl-3-(2-chloro-3,3,3-trifluoro-l-propenyl)-2,2-dimethyl cyclopropanecarboxylate, is a member of the pyrethroid pesticide chemical class which affects the nervous system and causes paralysis in insects (Briggs 1992, Walker et al. 1992). Bifenthrin is non-polar and has a high octanol-water coefficient (K_(oW) = 1.0 x 10~6), indicating bifenthrin has a low solubility and a correspondingly strong tendency to bind to crops (FMC 1983). Pure bifenthrin is an off-white to pale tan waxy solid with faint, slightly sweet smell (Meister 2002). Typical chemical structures of bifenthrin are given in Figure 1. In the United States, bifenthrin has been registered for used on greenhouse ornamentals and cotton (US EPA 1997).