More than 113 million Americans drink water that has been treated with chloramine, a compound created when chlorine and ammonia are combined. Getty Images/iStockphoto Researchers say they have identified a previously unknown, potentially toxic chemical in ...

A newly identified chemical byproduct may be present in drinking water in about a third of U.S. homes, a study found. Scientists think it might be toxic but do not yet know.

Scientists have identified the byproduct of a chemical used to disinfect tap water and prevent waterborne illnesses. Researchers urge testing for toxicity.