Sex reversal effects of environmentally relevant xenobiotic concentrationson the red-eared slider turtle, a species with temperature-dependent sex determination

Xenobiotics suspected of being estrogenic-the PCB aroclor 1242 and the pest icides toxaphene, dieldrin, p,p'-DDD, cis-Nonachlor, trans-Nonachlor, p,p'- DDE, and chlordane-were examined for their ability to override a male-produ cing incubation temperature and result in female hatchlings in the red-eare d slider, a turtle with temperature-dependent sex determination. Compounds were assayed in the environmentally relevant concentrations detected in all igator eggs from Lake Apopka, Florida, singly, in concert with one another, and with estradiol. Compounds assayed alone and resulting in significant s ex reversal were trans-Nonachlor, cis-Nonachlor, aroclor 1242, p,p'-DDE, an d chlordane. When administered with estradiol, only one of the compounds, c hlordane, caused sex reversal at significant levels. When applied together, however, the eight compounds assayed resulted in significant sex reversal. (C) 1999 Academic Press.