Assessing Levels and Potential Health Effects of Endocrine Disrupting Chemicals in Groundwater Associated with Karst Areas in Northeast Wisconsin

Background/Need:
In recent years, concern has risen over the presence of various nonpoint source pollutants in drinking water, including a class of organic chemicals called endocrine disrupting chemicals (EDCs). The growing prevalence of EDCs in environmental systems has been linked to the disruption of aquatic endocrine systems and increased incidence of certain human cancers. Groundwater in the Silurian aquifer of northeastern Wisconsin may be particularly susceptible to nonpoint source contamination due to the existence of shallow soils, dolomite bedrock, and karst features, which combine to facilitate the transport of surface runoff to groundwater. Land application of manure containing synthetic and endogenous hormones may be a significant source of nonpoint source pollutants, including EDCs, to groundwater in the heavily farmed regions of northeast Wisconsin.

Objectives:
The specific objectives of the study were:

1. To test for indicators of livestock and/or human fecal contamination (E. coli, fecal coliform, nitrates) in groundwater near farmland in the northeast Wisconsin counties of Brown, Calumet, Fond du Lac and Kewaunee.
2. To assess levels of EDC activity in groundwater near farmland in the northeast Wisconsin counties of Brown, Calumet, Fond du Lac and Kewaunee.
3. To determine whether EDC activity and fecal waste indicators in groundwater near farmland change after major recharge periods (e.g., rainfall; spring thaw).
4. To discern whether levels of groundwater contamination by EDCs correlate with other water quality indicators (nitrates, fecal coliform, E. coli levels).
5. To measure estradiol levels in water samples through use of an enzyme-linked immunosorbent assay (ELISA).