What you need to know about a newly defined chemical byproduct found in drinking water

A chemical byproduct found in some treated drinking water in the US that remained a mystery for more than four decades may have finally been identified by scientists.

The authors of the study, published Thursday in the journal Science, have named the byproduct chlornitramide anion and believe it is a byproduct of the breakdown of chloramine, which is used as a disinfectant in tap water.

The study does not suggest that tap water containing the byproduct is unsafe to drink, but does call for more research. It is estimated that more than 113 million people in the US drink chlorinated water

“It gives a name to this chemical that has been in our water for many years,” Dr. Stephanie Widmer, a board-certified medical toxicologist and emergency room physician who was not involved in the study, told ABC News. “The reality is that no one really knows much about this chloronitramide and its impact on human health, and more research needs to be done.”

“These disinfectant chemicals have been providing us with clean drinking water for decades, so there is no reason to fear drinking water as a result of this research,” she added.

The study authors suggest that adding a carbon filter to a sink or a stand-alone can may be a good option for those involved.

Here’s what you need to know about chemicals in drinking water.

How is drinking water treated?

Historically, water systems used chlorine, a chemical element, as a disinfectant for drinking water to remove harmful bacteria, viruses and certain microorganisms.

However, some studies have shown that chlorine can have harmful health effects. At low exposure it may irritate the eyes, skin or respiratory tract. At high levels it can cause tightness in the chest and difficulty breathing.

Chlorine is still the most commonly used disinfectant in drinking water at treatment plants in the US, but the Environmental Protection Agency sets legal limits on the amount that can be in drinking water and is safe for consumption.

Some water systems decided to use chloramine, a chemical compound formed by mixing chlorine and ammonia, as a disinfectant instead. Chloramine forms fewer byproducts than chlorine and is believed to be more stable, making it useful for water systems that deliver water over long distances.

What is this byproduct?

Although chloramine was commonly used as a disinfectant for drinking water, scientists noticed that byproducts appeared to form as a result. Some were easy to identify, but one was harder to spot.

“Chloramine itself: When you add a chemical to water, which is itself another chemical, chemical reactions occur; byproducts are created,” Widmer said.

Widmer explained that the byproduct, chloronitramide, has been in treated drinking water for years, but has been difficult to isolate and identify due to its chemical complexity.

By conducting a chemical study, the authors were able to break down the compound and identify its composition. It was synthesized in a laboratory and sent for analysis. The byproduct was subsequently detected in 40 drinking water samples from 10 U.S. drinking water systems.

“It’s not that a new chemical has been found, it’s just been there,” Widmer said.

Is tap water safe to drink?

It is not known what levels of chlornitramide anion in drinking water may pose a health risk.

Widmer said more research is needed on the byproduct and on the water supply in general, but the findings show that research and monitoring of our water systems is ongoing and scientists continue to gather new information.

Unless a boil water notice is issued in a community, there is nothing to indicate that tap water in a community is unsafe to drink, she said.

“We health professionals encourage people to drink a certain amount of water per day,” Widmer said. “Water is good for you. We shouldn’t be afraid to drink our water. But it is so important that there is ongoing research and monitoring of our water.”

“But because of this research that came out, no one should be afraid to drink water,” she continued. “It hasn’t changed anything regarding our water. It’s just another piece of information that we need to follow up on.”

Widmer said people can use sink filters or water pitcher filters if they prefer, but he recommended people do their research on what is filtered out of the water before making a purchase.