Determination of dieldrin in wool products by gas chromatography with microwave-assisted extraction

Abstract

Dieldrin is a moth-proofing agent that was banned by the Stockholm Convention in 2001. The amount of dieldrin in wool products was measured by a microwave-assisted extraction (MAE) method. The optimal conditions were as follows: extraction solvent, acetone/n-hexane (1:1 v/v); extraction temperature, 110 degrees C; extraction time, 10 min; solvent volume, 25 mL. When six samples were used, dieldrin contents determined by GC with the proposed MAE agreed closely with those by the Japanese official method using GC with solvent extraction and cleanup by column chromatography. The proposed MAE has two merits. First, the pretreatment of the MAE needs only 4 h for 11 samples, while that using the Japanese official method needs 2 days for six samples. Second, the volume of organic solvents used for the proposed method was only about one-tenth of that used in the Japanese official method. Our proposed method seems to be easy and useful for daily (routine) tests. Dieldrin contents of 28 used wool products, which were obtained from local clothing shops and ordinary homes, were determined by GC with the proposed MAE, and six products contained dieldrin (0.310-175 ppm). The dry cleaning of the woolen yarn containing 175 ppm dieldrin did not remove a significant amount of dieldrin. Therefore, it seems likely that dieldrin is still distributed slightly but widely throughout the world.

Simple Determination of 40 Organophosphate Pesticides in Raw Wool Using Microwave-Assisted Extraction and GC-FPD Analysis

“…These methods either need a cleanup step prior to GC analysis − or do not accomplish all of the necessary analytical quality control standards (i.e., high relative standard deviations (RSDs)) . Recently, microwave-assisted extraction (MAE) has been applied in pesticide residue analysis. − Stability problems under MAE conditions for some thermally labile OPs have been also reported . MAE has only been used for the analysis of dieldrin in processed wool products .…”

“…Recently, microwave-assisted extraction (MAE) has been applied in pesticide residue analysis. − Stability problems under MAE conditions for some thermally labile OPs have been also reported . MAE has only been used for the analysis of dieldrin in processed wool products . To our knowledge, analysis of OP residues in raw wool by MAE has never been undertaken.…”

“…13 MAE has only been used for the analysis of dieldrin in processed wool products. 8 To our knowledge, analysis of OP residues in raw wool by MAE has never been undertaken. The aim of this study was to develop and validate a fast and environmentally friendly multiresidue method for the analysis of OPs in raw wool samples.…”