Oral contraceptives are not a major estrogen source in drinking water- Industrial Ag is!
Environmental Health News Dec. 7, 2010
Wise, A , K O’Brien and T Woodruff. 2010. Are oral contraceptives a significant contributor to the estrogenicity of drinking water? Environmental Science & Technology http://dx.doi.org/10.1021/es1014482.
A new study finds that oral contraceptives are not the main culprit in estrogenic pollution of US and European rivers and drinking water. Instead, the contribution of contraceptives is quite small compared to other human, industrial and agricultural sources.
People are increasingly concerned about estrogenic pollution due to scientific studies that document the feminization of fish and other aquatic animals. Other studies have suggested that long term exposure to low levels of estrogens in water may adversely affect human health. This new information should ease concerns that contraceptives are a major factor contributing to feminized fish and frogs.
To see if OCs are mainly to blame, the researchers reviewed scientific studies from Europe and the United States that identified sources of estrogens in surface, source and drinking water. They paid close attention to the main estrogen in OCs, 17 alphaethinylestradiol (EE2). They also evaluated the public health impact of estrogenic pollution in drinking water.
The authors find that agricultural sources are an important source of estrogens in waterways because livestock produce 13 times more solid waste than humans. The animals can excrete both natural and pharmaceutical hormones. One study estimates that up to 90 percent of total estrogens in the environment could come from animal waste.
Water is also polluted with other human sources of estrogen chemicals, including natural hormones and other estrogen-containing prescription drugs, such as hormone replacement therapy.
Additionally, industrial and agricultural sources not only discharge estrogens, but they also release other harmful chemicals, such as pesticides, which can mimic estrogen. These compounds add to the overall estrogenic pollution of our water supplies.
The good news is that many wastewater and drinking water treatment plants can remove 80 to 99 percent of the synthetic estrogens. These treatments also seem to be effective at removing natural estrogens, too.
However, there is a downside. Natural and synthetic estrogens and estrogen-like compounds from agricultural sources – especially livestock – commonly enter waterways without treatment. Future efforts to reduce exposures may need to focus on reducing all types of estrogens in waterways.