An Associated Press investigation in March, 2008 found a variety of prescription medications in the drinking water in 24 metropolitan areas. The drugs end up in the water supply because people who take drugs do not absorb all of the medication that they take—so it is flushed down the toilet. The sewage is treated before the water is released into the drinking supply. However, all of the drug residue is not removed.
The AP found that drugs had been detected in the water systems of 24 metropolitan areas throughout the country. Drugs like antibiotics, sex hormones, pain medications, antidepressants and cholesterol medication are found in very small amounts throughout the nation’s water supply. The AP found that 28 of 35 metropolitan areas were contaminated with pharmaceutical residue. Six of those where residue was not found did not test for drugs, and one was awaiting results at the time the article went to press.