The AP reports that trace levels of prescription drugs have been found in drinking water of 24 major metropolitan areas, including San Francisco. The drug found in San Francisco’s drinking supply is estradiol. I looked up estradiol on Wikipedia. I’ve always loved the taste of San Francisco’s water, but this is frightening.

Estradiol (17β-estradiol) (also oestradiol) is a sex hormone. Mislabelled the “female” hormone, it is also present in males; it represents the major estrogen in humans. Estradiol has not only a critical impact on reproductive and sexual functioning, but also affects other organs including bone structure.

Several studies have noted that sperm counts have been declining in many parts of the world and it has been postulated that this may be related to estrogen exposure in the environment.[2] Suppression of estradiol production in a subpopulation of subfertile men may improve the semen analysis.[3]

Estradiol should not be given to women who are pregnant or are breastfeeding, women with unexplained uterine bleeding, certain forms of cancer, or prone to blood clotting disorders. The medication is to be kept away from children. Detailed prescription information is available [11]