“…The ecosystem and human-health risks associated with exposure to environmental concentrations of biologically active ECs are not known. Groundwater, especially in shallow unconfined aquifers, is vulnerable to contamination from many sources, including onsite wastewater disposal systems (Conn et al, 2006(Conn et al, , 2010Swartz et al, 2006;Stanford and Weinberg, 2010), which serve 420% of US households and 440% of residences in nine eastern US states (USEPA, 2002;U.S. In 2010, 42% of US community water supplies (serving 89 400 000 people) had groundwater sources (USEPA, 2013), and approximately 12% of US housholds depend on private wells for drinking water (US Census Bureau, 2011).…”