http://www.nytimes.com/2004/01/29/science/29VULT.html?ex=1075957200&en=3aa76c41184aca99&ei=5062&partner=GOOGLE<snip>There has been growing concern among scientists and environmentalists about the "vast amount of drugs that end up in the environment one way or another," he said, but no effect of this magnitude.
A study in 2002 by the United States Geological Survey found traces of many different pharmaceuticals and "personal care products" — including steroids, insect repellents and many others — in the American water supply. The effect of these traces is unknown, but the concern is about the unexpected. One laboratory study suggested, for example, that antidepressants like Prozac could trigger spawning in some shellfish.
The vulture finding in South Asia comes as a surprise: while environmental toxins had been suspected in the deaths, a pharmaceutical drug had not. Scientists in India and England suggested that disease was the cause of vulture deaths in India, but they found no infectious agent. The scientists who did the research in Pakistan said the situation in India was likely to be the same as that in Pakistan. But they said they did not have conclusive evidence.
Dr. Oaks said the investigation, which began in 2000, was prompted by reports of a 95 percent drop in the number of Asian white-backed vultures (Gyps bengalensis), Indian vultures (Gyps indicus) and slender-billed vultures (Gyps tenuirostris). All three are listed as critically endangered by the World Conservation Union, the international environmental agency based in Switzerland.