Monitoring of pyrethroid metabolites in human urine using solid-phase extraction followed by gas chromatography-tandem mass spectrometry

A method was developed for the determination of cis-, and trans-3-(2,2-dich lorovinyl)-2,2-dimethylcyclopropane-1-carboxylic acid (Cl(2)CA), cis-3-(2,2 -dibromovinyl)-2,2-dimethylcyclopropane-1-carboxylic acid (cis-Br(2)CA cis- , trans), 2-(4-chlorophenyl)-3-methylbutyric acid (2-CIBA), and 3-phenoxybe nzoic acid (3-PBA) in human urine. These compounds are major metabolites of commonly used synthetic pyrethroids permethrin, acrinathrin, cypermethrin, fenvelarate, deltamethrin, cyfluthrin and cyhalothrin, The method involves extraction of metabolites using solid-phase extraction, additional liquid- liquid extraction clean-up and derivatization followed by detection and qua ntification by sensitive gas chromatography-tandem mass spectrometry. 3-(2- methoxyphenoxy) benzoic acid was used as an internal standard. Recoveries o f spiked compounds ranged between 92.3 and 113.3%, and 87.4 and 121.1% at f ortification levels of 100 and 10 ng ml(-1), respectively. The relative sta ndard deviation was lower than 14.6% in all cases. The method was employed to detect and quantify pyrethroid metabolites in the urine of pest control operators and non-occupationally exposed subjects. The concentration of met abolites ranged from 269 pg ml(-1) for one of the non-exposed subjects to 2 .8 ng ml(-1) for one of the exposed pest control operators. (C) 1999 Elsevi er Science B.V. All rights reserved.