Investigation finds possibly toxic chemical in drinking water

A previously unidentified chemical has been discovered in the tap water of about a third of American homes, a new study has foundand scientists are actively investigating whether it is toxic.

The chemical, called chloronitramide anion, is formed 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.” That was reported by NBC News.

About 40 years ago, scientists became aware of a chemical byproduct from water that was treated with chloramine, but only with new tests have scientists been able to identify exactly what it is.

Chloronitramide anion has never been studied before, so it may be years before scientists are able to understand whether it is dangerous to consume. The study was published to highlight potential safety concerns and encourage further research.

Although there is currently no conclusive evidence to suggest that chlornitramide anion is harmful to health, it has some similarities to other “toxic molecules,” David Wahman, Ph.D., study author and research environmental engineer at the Environmental Protection Agency, told NBC News.

Part of the reason for the concern over the chemical’s potential toxicity is that it appears to be widespread in American drinking water.

“We looked for it in 40 samples in 10 US chlorinated drinking water systems in seven states. We found it in all the samples,” Wahman said.

He added that it is likely to be found in all water treated with chloramine that about 113 million American residents get in their taps.

The study also draws attention to the possible health consequences of using certain chemicals to treat tap water, not just chloramine. Some studies have linked disinfected drinking water with increased incidence of certain types of cancer.

“We don’t know what’s driving these. We have no idea if this connection is in any way related to these results,” Julian Fairey, the study’s lead author and associate professor at the University of Arkansas, told NBC News. “But we have unexplained occurrences of certain types of cancer from treated drinking water.”

But treating drinking water with chemicals reduces the presence of dangerous bacteria, especially those that cause cholera and typhoid, said Alan Roberson, executive director of the Association of State Drinking Water Administrators.

“The reason you add the chloramine — you want to kill bacteria and viruses, you have a real risk-risk trade-off,” he explained.

So is tap water safe to drink? Is it time for you to invest in a water filter? Here’s what you need to know.

Do I need a water filter?

The US Centers for Disease Control and Prevention recommends testing your home’s tap water for the presence of harmful bacteria or chemicals. Then you can buy a water filter designed to remove what you specifically found in your water.

If your water has no harmful bacteria or chemicals, you may decide not to use a filter. The CDC also points out that most home filters, like those in your fridge or in a pitcher, do not remove bacteria and typically only remove heavy metals and make the water taste better.

If you get your water from a well or rain, you should test it regularly for the presence of harmful bacteria or chemicals. For people who get their water from a public system, your utility company must provide a water safety report every year.

Before buying a water filter, check for an NSF International certification to ensure the product works and NSF International database to see what types of bacteria and chemicals your filter is certified to remove.

When it comes to chloronitramide anion, the chemical that the recent study identified, you can check your utility company’s website to see if they use chlorine or chloramine. An activated carbon filter found in many refrigerators and pitcher filters can remove the byproducts of chemicals used to disinfect tap water, but more research is needed, Wahman said.