Simultaneous Analysis of Organochlorinated Pesticides and Polychlorinated Biphenyls from Animal Tissue using Gas Chromatography-Mass Spectrometry Combined with Accelerated Solvent Extraction

The majority of fat and impurities in animal tissues influence the analysis result for low concentration organic compounds. To overcome this issue, the animal sample was extracted by accelerated solvent extraction (ASE) with methylene chloride/acetone (V:V=1:1), which reduced the co-extraction lipids during the extraction process. Gel Permeation Chromatography (GPC) combined with solid phase extraction (SPE) was applied to remove lipids from the sample solution. The GPC can remove most of the macromolecular lipids in samples, and the SPE with florisil can sufficiently reduce fat and small molecule impurity. The accuracy and sensitivity of the method can be improved by this pretreatment process. The compounds, including 17 organochlorinated pesticides and 7 indicator polychlorinated biphenyls in animal tissue, can be simultaneously analysed by Gas Chromatography Mass Spectrometry. The recoveries of 25 of the target compounds were in the range of 81.6%-113.4% and the method detection limits for dry samples were 1.02-3.59 ng/g. These results were superior to those of the national standard. This method improved the purification effect of animal samples, reduced the method detection limit, and enhanced the accuracy. It can be used to quickly and accurately determine the low content of persistent organic pollutants in animals.