Procedural contamination as a critical factor in the determination of polychlorinated biphenyls in biological matrices with low contamination levels: Advantages of supercritical fluid extraction

摘要

An analytical procedure for polychlorobiphenyls (PCBs) based on supercritical fluid and extraction (SFE) in mollusk and fish samples is presented. It uses isotopically labeled standards allows direct injection of the extract without any further manipulation other than solvent volume reduction. An evaluation of the accuracy and precision of the method is presented; the limit of determination is 10 pg/g per congener. The advantages of SFE in the analysis of samples with low (less than or equal to 1 ng/g total PCBs) contamination levels are illustrated. It is estimated that, at a contamination level of 1 ng/g total PCBs, the blank contribution of a traditional analytical method varies between 14 and 28%, whereas for an SFE method, it is significantly (at least three times) lower. (C) 1998 Academic Press. [References: 13]