Bioassay Guided Fractionation (Toxicity Identification and Evaluation) for the Determination of Estrogenic Agents in Environmental Samples

摘要

Toxicity Identification Evaluations (TIEs) have been an integral component of environmental toxicology for the determination of causal factors impacting biological responses in environmental matrices. Modifications of the "bioassay-guided" fractionation scheme have allowed environmental toxicologists to target specific biological responses in an attempt to determine "cause". This particular review focuses on the biological response of feminization or estrogenic activity resulting from exposure to environmental estrogens in aqueous media. While the approach has shown some promise with regard to specific estrogen receptor ligands, a more challenging aspect has been determining causative agents for the in vivo process of feminization, which is of more ecological relevance. Feminization is a complex biological response with multiple targets for xenobiotics to impair. Consequently, a whole animal approach calibrating vitellogenin to estradiol equivalents in environmental media will allow a more relevant assay for estrogenic activity that incorporates multiple mechanisms of action.