ABSTRACT
The Frog Embryo Teratogenesis Assay-Xenopus (FETAX), first developed in 1983 and ASTM International-approved, is one of the longer-running toxicity testing tools available to researchers seeking to understand the influences of contaminants on aquatic organisms. Toxicity tests and bioassays in support of Ecological risk assessment (ERA) are intended to provide indications that contaminated site conditions are health-offsetting to biota. ERA would be interested in the assay's outcomes if naturally, midblastula to early gastrula embryos somehow shed their jelly coats. Standard FETAX application that provides for skewed and overly protective aquatic assessment should, at a minimum, promote a much-needed dialogue on the purpose and design of toxicity testing in ERA. Beyond amending FETAX where the method has been demonstrated in one or more ways to be unnecessarily identifying unhealthful aquatic conditions, a cautious review of other established toxicity tests and bioassays should proceed.
