A Comparison of Hormone Levels and Land Use Patterns in a North-Central Texas Watershed
Abstract:Endocrine disrupting compounds (EDCs) are chemicals that interfere with normal hormone function, often at extremely small doses. The North Bosque Watershed in North-Central Texas was studied to characterize EDC levels, specifically hormones. The North Bosque River flows from Stephenville to Waco, Texas. The surrounding watershed is impacted by dairy operations, other agricultural uses, and urban areas. The dairy operations, or concentrated animal feeding operations (CAFOs), impact the watershed as shown by significant nutrient loading in the receiving waters. Many small urban communities contribute wastewater treatment plant (WWTP) discharges and urban runoff to the river or one of its tributaries. Water was sampled monthly for steroid hormones at standard sampling locations and hormones were measured via enzyme immunoassay (EIA). The steroid hormones included in this study are 17β-estradiol (E2), Progesterone (P), and Testosterone (T). The correlation coefficients of regression models applied to dairy land use verses geometric mean hormone levels ranged from 0.58 to 0.69. Inclusion of additional variables, e.g., urban land use, increased the correlation coefficients of the regression model up to 0.94 (geometric mean E2 predicted by a combination of dairy, urban, and wood & range land uses). The reference location (Neils Creek), no urban land use or dairy waste application fields in the watershed, had the lowest geometric mean levels across all the sampling sites: 3.37 ng/L P, 0.50 ng/L E2, and 0.21 ng/L T. The highest geometric mean hormone levels found in the watershed were 14.58 ng/L P, 3.71 ng/L E2, and 1.96 ng/L T. Fish studies showed vitellogenin (VTG) induction after 2 weeks exposure at 50X E2, 400X E2, and 50X E2/10X P (1X is approximately the geometric mean hormone levels found in the watershed across all sites).
Document Type: Research Article
Publication date: 2004-01-01
More about this publication?
- Proceedings of the Water Environment Federation is an archive of papers published in the proceedings of the annual Water Environment Federation® Technical Exhibition and Conference (WEFTEC® ) and specialty conferences held since the year 2000. These proceedings are not peer reviewed. A subscription to the Proceedings of the Water Environment Federation includes access to most papers presented at the annual WEF Technical Exhibition and Conference (WEFTEC) and other conferences held since 2000. Subscription access begins 12 months after the event and is valid for 12 months from month of purchase. A subscription to the Proceedings of the Water Environment Federation is included in Water Environment Federation (WEF) membership.
WEF Members: Sign in (right panel) with your IngentaConnect user name and password to receive complimentary access. Access begins 12 months after the conference or event
- Subscribe to this Title
- Membership Information
- About WEF Proceedings
- WEFTEC Conference Information
- Learn about the many other WEF member benefits and join today
- Ingenta Connect is not responsible for the content or availability of external websites