Plumbed drinking water in developed countries is pretty clean, but invisible contaminants can still lurk. One mysterious “phantom chemical” has haunted drinking water for decades, and now researchers have identified it – and found it’s completely new to science.

For more than four decades, scientists have noticed a mysterious chemical in the treated drinking water of millions of people in the United States, but no one’s been able to pinpoint exactly what it is – until now.

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

Researchers have identified a chemical in certain tap water across the United States as chloronitramide anion. Here's what to know.

A chemical byproduct found in some treated drinking water in the U.S. that remained a mystery for more than 40 years may have finally been identified by scientists. The authors of the study, published Thursday in the journal Science,

Simply because you could be drinking water that could be harmful. About a third of U.S. residents have been receiving tap water containing a previously unidentified chemical byproduct, a new study has found.