ABSTRACT
Sewage treatment processes clean wastewater to a level fit for reintegration into the aquatic environment. Sewage effluent has been determined as the point source for the endocrine disruption observed in biota, present in surface waters. The receiving aquatic environment for effluent discharge can be groundwater or more commonly surface waters. Estrogenic effects are reduced after discharge into receiving waters because of dilution, degradation, and sorption processes. Entrance of Endocrine disrupting chemicals (EDCs) to groundwater sources is by percolation or effluent recharge. The hydrophobic and low solubility nature of most EDCs decrease percolation through to underlying groundwater due to sorption to solid organic matter. The majority of data on EDCs are related to the aqueous environment from observations of abnormalities in biota, predominantly fish, present in surface waters. The presence of EDCs in receiving waters greatly impacts the organisms present. Consequences of EDCs in receiving waters can have adverse implications as evidenced by methylmercury poisoning in humans.
