One-Third of the Drinking Water in the U.S. Contains Possibly Toxic Chemical

Did you know the cool, refreshing glass of water you pour from your tap may be hiding a secret? According to a study spearheaded by a research environmental engineer with the Environmental Protection Agency (EPA), based on sampling, something like one-third of water in the U.S. is likely to contain chloronitramide anion.

If you've never heard of the chemical before, you're not alone. The compound has yet to be studied, which means experts don't yet know whether it's dangerous for the public. The good news is that the experts say they do have some ideas based on some of the known molecules considered in its makeup, which means they have a pretty good idea of whether it's harmful to your health to drink it.

Here's what we know about the drinking water chemical.

According to a November 2024 study published in Science, 40 samples of drinking water taken from 10 water systems tested positive for chloronitramide anion. The anion is a result of the chemical process that happens in water treated with chloramines, which help keep potentially harmful microorganisms from growing in our public water systems.

While scientists have known for years that anions can develop as part of this process, they were unable to figure out exactly which ones are created until the time of this study.

That means they haven't been able to test the chloronitramide anion's toxicity levels, which is how they determine whether or not it presents a problem to the humans who consume it. One thing they do know, however, is that the molecules closely resemble known toxins, which raises some concerns.

According to the study's co-author, David Wahman, who spoke with NBC News, it's likely that 113 million U.S. residents have been drinking this compound in their tap water for the last 40 years, which is when they first became aware that something was being created as part of the chloramine process.

Wahman told the outlet that there are possible connections between the chemicals used to treat public water systems, including an increase in cancer rates.

"We don’t know what’s driving these," lead study author Julian Fairey told NBC News. "We have no idea if this compound is in any way related to those outcomes. But we have unexplained incidents of certain types of cancer from treated drinking water," he explained.

That may leave people with questions about whether or not they can filter that compound out of their water at home. It seems like the answer to that question is maybe.

Today notes that an activated carbon filter may remove some byproducts from the chloramine process. However, there just hasn't been enough research done to know whether that includes chloronitramide anion.

To find out whether your tap water may contain the compound you can check the website of your utility company and see if they use chloramine in the first place. If they don't, your water is likely free from chloronitramide anion.

Even if they do use chloramine, it doesn't sound like there's any reason to panic since researchers have yet to make any connections between the compound and adverse health outcomes.