Endocrine-Disrupting Compounds and Mixtures: Unexpected Dose–Response
- 1 February 2004
- journal article
- research article
- Published by Springer Science and Business Media LLC in Archives of Environmental Contamination and Toxicology
- Vol. 46 (2), 265-269
- https://doi.org/10.1007/s00244-003-2110-1
Abstract
The current study examined the effects on the red-eared slider turtle of extremely low doses of three endocrine-disrupting compounds (EDCs)—trans-Nonachlor, chlordane, and p,p′-DDE—singly and in mixtures. Previous studies using the red-eared slider turtle have proven its value as an organism for obtaining information about the effects of endocrine-disrupting compounds. The sex of the turtle, easily manipulated by exposure during embryogenesis, continues to be a marker of effects. When red-eared slider turtle embryos incubating at a temperature that normally produces a male-biased sex ratio are exposed to these compounds singly, the sex ratio of the resulting hatchlings shifts significantly to a female bias. The current work offers further evidence that the red-eared slider turtle provides a way to quantify the effects of mixtures and has the potential as a model for evaluating additivity and synergy. The results provide information about how very low doses (parts per billion) of these compounds behave in mixtures. The dose ranges were 0.125–0.5 ng/egg for trans-Nonachlor and chlordane and 7–28 ng/egg for p,p′-DDE. Results suggest the possibility that two of the compounds may exert effects in mixtures via complementary pathways; when applied singly, the effects of chlordane and p,p′-DDE were inversely related to dose, but in mixtures, which were essentially a greater dose of EDC, the compounds had an increased effect. In all cases, mixtures resulted in 100% females.Keywords
This publication has 3 references indexed in Scilit:
- Endocrine Disruptors: Present Issues, Future DirectionsThe Quarterly Review of Biology, 2000
- Embryonic treatment with xenobiotics disrupts steroid hormone profiles in hatchling red-eared slider turtles (Trachemys scripta elegans).Environmental Health Perspectives, 2000
- Sex Reversal Effects of Environmentally Relevant Xenobiotic Concentrations on the Red-Eared Slider Turtle, a Species with Temperature-Dependent Sex DeterminationGeneral and Comparative Endocrinology, 1999