Evaluation of extraction recoveries for organometallic determinations in environmental matrices

The extraction of organometallic compounds from environmental samples is a very complex matter in which two conflicting issues have to be balanced: obtaining an adequate recovery, on the one hand, and preventing losses - especially destruction of the compound(s) - on the other. The extraction should be done in such a way that the analyte is separated from the interfering matrix without Toss, contamination, or change of the speciation, and with a minimum of interferences. The quality control of analytical measurements implies that the extraction recoveries are verified, which can be done in several ways. Th is article discusses the evaluation of extraction recoveries, as carried out in collaborative projects on organotins, methylmercury and trimethyl-lead, and reviews current practices used in evaluating extraction recoveries for these compounds. (C) 2000 Elsevier Science B.V. An rights reserved.