MP5 Agrochemicals and Pesticides
Monday, 14 November 2005: 8:00 AM - 5:30 PM in Exhibit Hall

(JOH-1117-835471) Dynamic sonicator-assisted extraction for organophosphates and carbamate insecticides from avian tissue and gut contents.

Paulson, B.¹, Sandercock, B.², Johnson, K.^{1, 3}, ¹ Department of Chemistry, Southern Illinois University, Edwardsville, IL, USA² Division of Biology, Kansas State University, Manhattan, KS, USA³ Environmental Sciences Program, Southern Illinois University Edwardsville, Edwardsville, IL, USA

ABSTRACT- A great amount of effort has been put into the reduction of non-target insecticide exposure to wildlife. However, insecticide effects on wildlife remain a threat to many non-target species, especially avian species. Organphosphorus (OP) and carbamate (CB) insecticides are widely used around the world and have replaced the more persistent organochlorinated insecticides such as DDT. Currently, OPs and CBs are being phased out in the United States. They are, however, widely used in third world countries and will remain in use for some time. As such, it is important to have affordable methods available to monitor these insecticides in a variety of matrices. Traditional methods include Soxhlet extractions, which are time consuming, costly, and generate a large volume of solvent waste. Currently, a number of researchers are developing methods using accelerated solvent extractions. These techniques use low volumes of solvents and can take as little as 25 minutes; however, the instrumentation can be cost prohibitive. To aid those with cost constraints, we have developed a method to extract trace amounts of insecticides in 1- to 25 g tissue/gut content samples using a dynamic sonication with an in-situ cleanup. Briefly, solvent is pumped through coiled tubing that is in a heated water bath with a sonicator containing a large diameter column with the sample inside. The sample is packed in the column such that the solvent first flows through the sample, then anhydrous sodium sulfate, followed by florisil. A variety of parameters, such as solvent, pressure, flow rate, water bath temperature, and solvent volume were evaluated. Recoveries of a number OPs and CBs were over 90% using this novel method compared to 80% using a modified separatory funnel method. Currently, this technique is being utilized in a study evaluating the ecotoxicity of insecticides on neotropical migratory shorebirds.

Key words: organophosphates, carbamates, dynamic sonication, extraction method