WP1 Wastewater Treatment Effluents: Endocrine Disrupters and Pharmaceuticals
Wednesday, 16 November 2005: 8:00 AM - 6:30 PM in Exhibit Hall

(GRA-1117-833014) Fate of environmental estrogens in a wastewater-dominated stream with feminized fish populations.

Gray, James¹, Vajda, Alan ², Woodling, John², Norris, David ², Barber, Larry ¹, ¹ US Geological Survey, Boulder, CO, USA² University of Colorado, Boulder, Boulder, CO

ABSTRACT- Wastewater impacted streams contain biogenic contaminants, such as 17-beta-estradiol (E2), that can elicit endocrine disrupting effects in fish at low concentrations (1 ng/L), and industrial chemicals, such as nonylphenol (NP), that induce similar effects at higher concentrations (>1000 ng/L). Furthermore, a variety of compounds found in wastewater effluents including steroids, detergents and certain human pharmaceuticals are known to be biologically active but have unknown effects at environmentally relevant concentrations. A Lagrangian sampling protocol was employed in conjunction with analysis of intrinsic geochemical tracers and a conservative tracer pulse to characterize contaminant hydrology in Boulder Creek, CO downstream of a wastewater treatment plant (WWTP) discharge. Ongoing work presented in a related abstract shows that white suckers (Catostomus commersoni) congregating downstream of the WWTP were feminized relative to upstream populations. Induction of vitellogenin and intersex gonadal tissue was only observed downstream of the WWTP and the sex ratio (85% female) was no longer evenly distributed. Although E2 and NP concentration gradients between the upstream and downstream sites were steep, other environmental factors also may contribute to the apparent feminization of white suckers below the WWTP. To account for these factors, juvenile white suckers and fathead minnows (Pimephales promelas) will be exposed to wastewater effluent and upstream water in flow-through aquaria where environmental variables will be controlled. These aquaria will be contained in an on-site laboratory, so fish will experience actual environmental exposures over the course of a 28-day experiment. During the course of the experiment, levels of endocrine disrupting chemicals in the aquaria will be monitored in order to establish a causative link between chemical exposure and abnormal sexual development in the fish.

Key words: endocrine disruption, environmental estrogens, fate and transport