Extraction and Analysis Methods for the Determination of Pyrethroid Insecticides in Surface Water, Sediments and Biological Tissues at Environmentally Relevant Concentrations

Abstract

The aim of this study was to develop and validate chemical methods for measuring pyrethroid insecticides at environmentally relevant concentrations in different matrices. The analytes included six synthetic pyrethroids with the highest agricultural and commercial structural uses in California: bifenthrin, cyfluthrin, cypermethrin, esfenvalerate/fenvalerate, lambda-cyhalothrin, permethrin, and their corresponding stereoisomers, which includes enantiomers, diastereomers and racemic mixtures. Fortified water samples were extracted for analysis of synthetic pyrethroids using liquid-liquid extraction, while fortified sediment and fish tissue samples were extracted using pressurized fluid extraction followed by gel permeation chromatography (GPC) to remove matrix interferences. A florisil column was used for additional cleanup and fractionation of sediment and tissue extracts. Extracts were analyzed using dual column high resolution gas chromatography with electron capture detection (GC/ECD) and confirmation was obtained with gas chromatography mass spectrometry using a quadrupole ion trap detector in MS-MS mode. Method detection limits (MDLs) have been established for water (1-3 ng/L), sediment (0.5-4 ng/g dry weight) and tissue (1-3 ng/g fresh weight). Mean percent recoveries of fortified blanks and samples ranged from 75 to 115% with relative standard deviation (RSD) values less than 20% for all target compounds.

Effects of acute exposure to bifenthrin on some haematological, biochemical and histopathological parameters of rainbow trout (Oncorhynchus mykiss)

“…The water was extracted with ethyl acetate and the extract dried with sodium sulphate, concentrated and then analyzed by gas chromatography with an electron capture detector (µECD). The reporting limit for this method is 0.01 µg/l (Mekebri et al, 2008). During the test, water temperature and pH were 15.8-8.43, respectively.…”

Simultaneous determination of pyrethroids from pesticide residues in porcine muscle and pasteurized milk using GC

“…Therefore, extraction without an additional cleanup procedure was used in subsequent experiments in this study. It has been stated that SPE is not an effective extraction technique for PYRs, as they have a strong tendency to absorb to virtually all surfaces they come in contact with [26]. As recommended by the KFDA MRLs for Pesticides in Foods, Seoul, 2005, the fortification levels for the recovery tests were performed at half, two, and four times the MRL (n F 6).…”

“…The applicability of the method for analysis of incurred samples collected from major cities in the Republic of Korea was then evaluated. Many PYRs possess one or more halogenated atoms, which make them sensitive to GC-ECD [26].…”

The Effects of Pyrethroid and Triazine Pesticides on Fish Physiology

“…Tanks for all treated fish and controls were replicated, Presence of the tested substance (above 80% of the nominal concentration) was ensured through a 12 h exchange of the water bath. Determination of pyrethroid concentration in water was measured using gas chromatography (Mekebri et al, 2008). Forty-eight experimental (8 fish from each pesticide duplicated) carp or rainbow trout and sixteen control carp or rainbow trout were selected at random and used for haematological, biochemical, and histological examination at the end of the 96 h exposure.…”