Mystery Chemical Found In Millions Of American's Tap Water Could Be Toxic
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Mystery Chemical Found In Millions Of American's Tap Water Could Be Toxic

Researchers have found and finally identified a mystery chemical in millions of American's tap water. The downside is that it could be toxic.

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The chemical baffled researchers for some time. But they finally identified chloronitramide anion in millions of Americans's tap water. Chloronitramide anion forms from chloramine as it decomposes. Chloramine is used to treat drinking water against diseases such as cholera.

However, it may have had an unintended side effect. According to the journal Science, researchers detected the mystery chemical in 40 drinking water samples from 10 US systems. Right now, more than 113 million Americans use chloraminated water.

Researchers believe that the chemical could be toxic.

"It's a very stable chemical with a low molecular weight," explained Julian Fairey, an associate professor of civil engineering at the University of Arkansas and first co-author of the new paper. "It's a very difficult chemical to find. The hardest part was identifying it and proving it was the structure we were saying it was."

They found that there were strong concentrations of 100 micrograms per liter. This is far beyond regulatory limits for disinfection products in the water supply. The chemical wasn't found in either ultrapure or chlorinated waters.

Mystery Chemical In Tap Water

Fairey sounded the alarm, saying there was a "good reason to investigate the toxicity."

"It's well recognized that when we disinfect drinking water, there is some toxicity that's created. Chronic toxicity, really," Fairey said. "A certain number of people may get cancer from drinking water over several decades. But we haven't identified what chemicals are driving that toxicity. A major goal of our work is to identify these chemicals and the reaction pathways through which they form."

That certainly doesn't sound ominous, does it? Meanwhile, studies have found that chlorine water isn't all that it is cracked up to be either. Studies found long-term exposure to chlorinated tap water linked to cancer and birth defects.

As such, municipal water supplies swapped from chlorine to chloramine. But now, they have to deal with this mystery chemical in the water.

Water expert Dr. David Sedlak told CNN this week that in "the last 30 years we've seen a little bit of buyer's remorse for this switch from free chlorine to chloramines, because we keep discovering these chloramine disinfection byproducts."

"The challenge is, we don't really know about the health impacts, because unlike the free chlorine disinfection byproducts, there just hasn't been as much toxicology done on these compounds," added Sedlak, vice chair for graduate studies and the Plato Malozemoff Professor of Environmental Engineering at UC Berkeley, who was not involved with the new study.