Embryonic Treatment with Xenobiotics Disrupts Steroid Hormone Profiles in Hatchling Red-Eared Slider Turtles (Trachemys scripta elegans) Emily Willingham, Turk Rhen, Jon T. Sakata, and David Crews Institute of Reproductive Biology, The University of Texas, Austin, Texas, USA Abstract Many compounds in the environment capable of acting as endocrine disruptors have been assayed for their developmental effects on morphogenesis ; however, few studies have addressed how such xenobiotics affect physiology. In the current study we examine the effects of three endocrine-disrupting compounds, chlordane, trans-nonachlor, and the polychlorinated biphenyl (PCB) mixture Aroclor 1242, on the steroid hormone concentrations of red-eared slider turtle (Trachemys scripta elegans) hatchlings treated in ovo. Basal steroid concentrations and steroid concentrations in response to follicle-stimulating hormone were examined in both male and female turtles treated with each of the three compounds. Treated male turtles exposed to Aroclor 1242 or chlordane exhibited significantly lower testosterone concentrations than controls, whereas chlordane-treated females had significantly lower progesterone, testosterone, and 5-dihydrotestosterone concentrations relative to controls. The effects of these endocrine disruptors extend beyond embryonic development, altering sex-steroid physiology in exposed animals. Key words: Aroclor 1242, chlordane, PCBs, steroid hormone, xenobiotic. Environ Health Perspect 108:329-332 (2000) . [Online 22 February 2000] http://ehpnet1.niehs.nih.gov/docs/2000/108p329-332willingham/ abstract.html Address correspondence to D. Crews, Institute of Reproductive Biology, University of Texas at Austin, Austin, TX 78712-1064 USA. Telephone: (512) 471-1113. Fax: (512) 471-6078. E-mail: crews@mail.utexas.edu We thank the five anonymous reviewers for their helpful comments and S. Woolley for her technical assistance. This work was supported by NSF IBN-9723617 to D.C., an Individual National Research Service Award (MH 11369) from the National Institute of Mental Health to T.R., and an NSF Predoctoral Fellowship to J.T.S. Received 14 July 1999 ; accepted 29 October 1999. The full version of this article is available for free in HTML or PDF formats. |