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.
The Summary A newly identified chemical byproduct may be present in drinking water in about a third of U.S. homes, a study found. Scientists do not yet know whether the byproduct is dangerous. But some are worried that it could have toxic properties because of similarities to other chemicals of concern. About a third of U.S. residents have been receiving tap water containing a previously unidentified chemical byproduct, a new study has found. Some scientists are now concerned — and actively investigating — whether that chemical could be toxic. The newly identified substance, named "chloronitramide anion," is produced when water is treated with chloramine, a chemical formed by mixing chlorine and ammonia. Chloramine is often used to kill viruses and bacteria in municipal water treatment systems. Researchers said the existence of the byproduct was discovered about 40 years ago, but it was only identified now because analysis techniques have improved, which finally enabled scientists to determine the chemical's structure. It could take years to figure out whether chloronitramide anion is dangerous — it's never been studied. The researchers reported their findings Thursday in the journal Science, in part to spur research to address safety concerns. The scientists said they have no hard evidence to suggest that the compound represents a danger, but that it bears similarities to other chemicals of concern. They think it deserves scrutiny because it's been detected so widely. "It has similarity to other toxic molecules," said David Wahman, one of the study's authors and a research environmental engineer at the Environmental Protection Agency. "We looked for it in 40 samples in 10 U.S. chlorinated drinking water systems located in seven states. We did find it in all the samples." Chloronitramide anion is produced as chloramine decays over time. It's likely to be found in all drinking water treated via this method, he said. The fact that a byproduct with unknown…