AWWA SOURCES55705

Endocrine disrupting chemicals present in natural water systems that receive treated wastewater can produce adverse health effects among exposed organisms. These include a degree of feminization, as evidenced by the production of vitellogenin by male fish. A variety of estrogens and other endocrine disruptors survive conventional wastewater treatment in trace quantities. In this study, wastewater effluent and groundwater samples were analyzed for estrogenic activity using a competitive receptor-binding assay. Samples were taken at various points along the treatment process from the Roger Road Wastewater Treatment Plant in Tucson, as well as from the Sweetwater Recharge Facility near the treatment plant. A 3-fold decrease in estrogenic activity typically occurred during secondary treatment. There was no further improvement in this respect during secondary clarification, chlorination, or dechlorination. Removal of estrogenic activity during infiltration and storage underground was also examined. Wastewater constituents that survived secondary treatment were further reduced when effluent was infiltrated through approximately 100 feet of unconsolidated sediments to the local aquifer. Residual estrogenic activity was typically reduced by> 95 percent during infiltration. Includes 12 references, tables, figures.