Drugs in our water supply?

We put this question to Professor Chris Cooper:

That's an interesting question. There's always scare stories about what's in my water, what harm is it doing? There's a long-term slight concern about female hormones getting into the water at very low levels. It's not likely to be a big health problem but there have been concerns in the past. In terms of drugs and sport there's no way you can get enough drugs for you water supply to help with sport or to fail a drugs test. The small part of that question is not a problem. The general human health point is a whole other major issue which I think is probably overstated but it is out there.