Modeling Estrogenic Activity in Streams Throughout the Chesapeake Bay Watershed
Abstract
Estrogenic endocrine disrupting compounds (EDCs) vary in magnitude and composition in surface waters under the influence of different landscape sources and landcover gradients. Estrogenic activity in surface waters may lead to adverse effects in aquatic species at both individual and population levels and can be observed through the presence of biomarkers such as intersex (testicular oocytes; TO) and vitellogenin induction in male fish. In the Chesapeake Bay Watershed (CBW), TO have been observed in smallmouth bass in areas with increased estrogenic activity levels and are attributed to landscape sources of EDCs. However, there are many small catchments where smallmouth bass and other potentially affected fish species reside that have not been sampled for estrogenic activity, and thus little is known on the potential for endocrine disruption in these areas. Previous surface water sampling throughout the CBW to quantify estrogenic activity was leveraged to build random forest models to predict estrogenic activity at unsampled sub-catchments within the Watershed. Using the U.S. Environmental Protection Agency effects-based threshold of 1.0 ng/L 17 β-estradiol equivalents, sub-watersheds predicted to exceed this value were categorized as at-risk for adverse effects from exposure to estrogenic compounds and compared against state-designated healthy watersheds and recreation access locations. This study is the first Chesapeake Bay-wide assessment of estrogenic activity, providing a foundation for future risk assessment and management design efforts. This talk will highlight model results and key variables driving estrogenicity in the CBW and outlines future directions for Chesapeake Bay Watershed-scale analyses.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2020
- Bibcode:
- 2020AGUFMH116.0014G
- Keywords:
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- 0470 Nutrients and nutrient cycling;
- BIOGEOSCIENCES;
- 1831 Groundwater quality;
- HYDROLOGY;
- 1871 Surface water quality;
- HYDROLOGY;
- 1879 Watershed;
- HYDROLOGY