A new report that appears in the American Chemical Society’s journal ‘Environmental Science & Technology’ has laid one urban myth to rest. Now it seems that, contrary to popular belief, birth control pills account for less than 1 percent of the estrogens found in US drinking water supplies.
The researchers – Amber Wise, Kacie O’Brien and Tracey Woodruff – noted in their analysis the ongoing concern about possible links between chronic exposure to estrogens in the water supply and fertility problems and other adverse human health effects. These effects are related to the concern about estrogen as an endocrine disruptor with possible adverse effects on people and wildlife once it enters into drinking water supplies.
Almost 12 million women of reproductive age in the United States take the pill, and thus their urine contains the hormone estrogen. This is the basis of the belief that oral contraceptives are the major source of the hormone in lakes, rivers, and streams. However, it seems that sewage treatment plants remove virtually all of the main estrogen — 17 alpha-ethinylestradiol (EE2) — in oral contraceptives and so the scientists decided to pin down just what the main sources of estrogens in water supplies actually were.
Their analysis found that EE2 has a lower predicted concentration in U.S. drinking water than natural estrogens from soy and dairy products and animal waste used untreated as a farm fertilizer. And that all humans (men, women and children, and especially pregnant women) excrete hormones in their urine, not just women taking the pill. Some research cited in the report suggests that animal manure accounts for 90 percent of estrogens in the environment. Other research estimates that if just 1 percent of the estrogens in livestock waste reached waterways, it would comprise 15 percent of the estrogens in the world’s water supply.
As it seems that animals, and not humans, are chiefly responsible for the hormones in our water supply we can stop feeling guilty about our method of contraception, or HRT, damaging the environment – although we can’t always say the same for our health.