Water is very rarely pure H2O. It tends to grab particles from things it passes and brings them along for the ride. Whether flowing in a mountain stream or pouring out of your faucet, water usually contains more than just oxygen and two hydrogen atoms. Some of these piggybackers are harmless, but many are not.
The U.S. Environmental Protection Agency, which oversees the safety of tap water, currently regulates different contaminants. The agency recognizes but does not regulate an additional 51 contaminants.
Water is one of few common resources on which all of us depend for life, so it’s important for us to be responsible stewards. Read on to learn about some of the potential dangers hiding in your tap and what you can do about them.