Most pharmaceutical estrogens and xenoestrogens are introduced into the environment through municipal waste water treatment plant (WWTP) effluent sources. These effluents contain synthetic compounds; surfactants, flame retardants and halogenated hydrocarbons that can mimic estrogens; and are discharged directly into rivers and lakes. As rivers and lakes are used for water and food supply, and recreation, and wastewater effluent usage increases, the presence and concentration of xenoestrogens in surface water becomes a valid public health concern. Additionally, many USA cities have significant combined sewer overflows releasing untreated sewage directly into surface waters, thus increasing the amounts of xenoestrogens finding their way into drinking water supplies and commercial and subsistence fishing habitat.
In the United States, humans are exposed daily to both pharmaceutical and xenoestrogens which have been implicated in various human health outcomes, such as testicular dysgenesis syndrome including testicular cancer and breast cancer in women. Also, they can have adverse reproductive effects in aquatic wildlife through sex reversals, production of intersex individuals, alterations in mating, and prevention of gonadal maturation. Combinations of estrogenic compounds are present in municipal WWTP effluents but, the natural estrogens, 17β-estradiol (E2) and estrone (E1), and the synthetic E2 derivate 17α-ethinylestradiol (EE2) are most responsible for in vitro estrogenic activity. Each xenoestrogen exhibits its own wildlife or human health risk, but synergistic effects could occur with xenoestrogen mixtures. Less than 1 ng/L EE2 can cause feminization of male fishes, 4 ng/L caused abnormal reproductive development (male fathead minnows). E2 has been detected at concentrations from 1 ng/L to 80 ng/L. Total estrogenicity (E2 equivalents) of 147 ng/L has been measured in WWTP effluent. Nonylphenol, a surfactant and brominated biphenyls, a flame retardant have been detected between 0.1–3.7 μg/L and 0.3–4.6 mg/kg (on suspended particles) respectively.
Understanding the species and xenoestrogen concentrations in surface water is imperative for environmental public health tracking of associated disease states. Such research will determine the necessity for utilizing limited and competing public financial resources to invest in technology to remove xenoestrogens from surface waters and, in regulation of fish or wildlife consumption from our rivers and lakes.