Meeting Abstract

P1.78  Sunday, Jan. 4  Effects of 4-tert-octylphenol on amphibian metamorphosis WOLFF, S.W.*; ELY, T.E.; CHANTAROJWONG, T.M.; HELBING, C.C.; PROPPER, C.R.; Northern Arizona University; Northern Arizona University; Northern Arizona University; University of Victoria; Northern Arizona University sw245@nau.edu

Many chemicals released into the environment impact physiological function. These compounds are often referred to as endocrine disrupting compounds (EDCs). Some EDCs impact thyroid function. Because metamorphosis in amphibians is under direct regulation by thyroid hormone, this developmental marker provides a strong endpoint for evaluation of a compounds potential to disrupt thyroid hormone function. Estrogen exposure can impact thyroid and/or thyroid hormone function. Octylphenol (OP), a common organic pollutant found in wastewater effluent has estrogen-like actions. We looked at effects of environmentally relevant levels of octylphenol on metamorphosis in the amphibian model, Xenopus laevis. We exposed animals (90/treatment) to control water, water containing 10^-9 M estradiol as a positive control, and three concentrations of octylphenol (10^-7 M, 10^-8M or 10^-9M). We evaluated timing of development and growth. We found no effects on developmental stages or mass across any of the treatment groups, suggesting that neither low levels of E₂ nor OP impacts thyroid hormone- related development. Our results demonstrate that exposure to OP at environmentally relevant levels does not impact thyroid-mediated developmental measures. Future studies will examine how OP impacts development of the gonads.