Organochlorine pesticide analysis in oil seeds and vegetable oil: simplification of silica gel clean-up and elimination of chlorinated solvents

Abstract

For the determination of organochlorine pesticides (OCPs) in vegetable oils and oil seed samples, a solid-phase extraction method is described, modified from that developed by Steinwandter, with silica gel columns activated with a 10% water content. In comparison to the method developed by Steinwandter, we reduced the amount of solvents and chemicals required for sample preparation and substituted dichloromethane by the much less toxictert-butylmethyl ether in the eluent mixture. In this manner the sample preparation technique becomes more convenient, cheaper and ecologically more justifiable. Under the specified sample preparation and elution conditions 1 g silica gel retained about 16 mg triglycerides whereas the OCPs were quantitatively eluted. The recoveries for hexachlorobenze, (HCB) α-HCH, Lindane (γ-HCH) γ-HCH, Heptachlor, Heptachlorepoxid,o,p′-DDE,p,p′-DDE, Dieldrin,o,p′-DDT,p,p′-DDT were between 75 and 90%. The reproducibility of the total method was excellent as well as its ruggedness.