title: Comparing predicted estrogen concentrations with measurements in US waters.
abstract: The range of exposure rates to the steroidal estrogens estrone (E1), beta-estradiol (E2), estriol (E3), and ethinyl estradiol (EE2) in the aquatic environment was investigated by modeling estrogen introduction via municipal wastewater from sewage plants across the US. Model predictions were compared to published measured concentrations. Predictions were congruent with most of the measurements, but a few measurements of E2 and EE2 exceed those that would be expected from the model, despite very conservative model assumptions of no degradation or in-stream dilution. Although some extreme measurements for EE2 may reflect analytical artifacts, remaining data suggest concentrations of E2 and EE2 may reach twice the 99th percentile predicted from the model. The model and bulk of the measurement data both suggest that cumulative exposure rates to humans are consistently low relative to effect levels, but also suggest that fish exposures to E1, E2, and EE2 sometimes substantially exceed chronic no-effect levels.
authors.affiliation: Ecological Exposure Research Division, National Exposure Research Laboratory, U.S. Environmental Protection Agency, 26 W. Martin Luther King Drive, Cincinnati, OH 45268, USA. kostich.mitchell@epa.gov
authors.forename: Mitch
authors.initials: M
authors.lastname: Kostich
authors.forename: Robert
authors.initials: R
authors.lastname: Flick
authors.forename: John
authors.initials: J
authors.lastname: Martinson
mesh_terms: D052244:Endocrine Disruptors / Q000032:analysis; D004784:Environmental Monitoring; D004958:Estradiol / Q000032:analysis; D004964:Estriol / Q000032:analysis; D004967:Estrogens / Q000032:analysis*; D004970:Estrone / Q000032:analysis; D004997:Ethinyl Estradiol / Q000032:analysis; D005618:Fresh Water / Q000737:chemistry*; D014481:United States; D014874:Water Pollutants, Chemical / Q000032:analysis*; D014877:Water Pollution, Chemical / Q000706:statistics & numerical data*
chemical_list: D052244:Endocrine Disruptors; D004967:Estrogens; D014874:Water Pollutants, Chemical; D004970:Estrone; D004997:Ethinyl Estradiol; D004958:Estradiol; D004964:Estriol