Get Healthy!

• Posted January 20, 2026

Some Popular Bottled Waters Contain Unregulated Chemicals, Researchers Say

Reaching for a bottle of water may feel like the safest way to stay hydrated. But new research suggests bottled water isn’t as pure as many people think and may contain harmful chemicals.

Researchers found dozens of chemicals in popular bottled water brands, including some chemicals that are not regulated by the government.

The study — scheduled for publication in the March issue of the journal Water Research — tested 10 popular bottled water brands for 64 regulated and unregulated chemicals called disinfection byproducts, or DBPs.

All bottled waters tested contained DBPs, albeit at much lower levels than tap water, the researchers found.

"Overall, I think this is a good finding for bottled water," study co-author Susan Richardson, a chemistry professor at the University of South Carolina, told Newsweek. "Before this study, there was almost no information on the vast majority of toxic priority, unregulated DBPs. Now we have it."

Disinfecting water is essential to prevent deadly illnesses like cholera and typhoid. But the process can also create disinfection byproducts, which may pose health risks.

"Many human epidemiologic studies show a risk of bladder cancer; some show a risk of colorectal cancer, and some show a risk of miscarriage and birth defects," Richardson said.

In this study, she and her team found that:

• Bottled waters labeled as spring water generally had lower levels of DBPs.

• Bottled waters made from purified tap water had higher levels.

• Two grocery-store brands showed especially high toxicity, up to 43 and 83 times higher than other bottled waters tested.

On average, researchers found three types of DBPs in bottled water, compared with 37 types typically found in tap water.

One specific chemical of concern, dibromoacetonitrile, is a possible cancer-causing chemical that is not regulated. Researchers said its levels were low and similar to what’s found in tap water.

The U.S. Food and Drug Administration (FDA) regulates some chemicals in bottled water, including bromate and trihalomethanes. 

But many of the chemicals identified in the study are not regulated by either the FDA or the U.S. Environmental Protection Agency.

"Unregulated DBPs are of greatest concern because of their toxicological profile, however, study of their health effects has not produced evidence that has required them to be regulated yet," said Natalie Exum, an assistant professor at Johns Hopkins Bloomberg School of Public Health, who reviewed the findings. "This means that we may be consuming them without proper understanding of their harm to our health."

Some experts say the findings don’t mean bottled water is safer overall.

"In my opinion tap water is still safer than bottled water," Sherri Mason, director of Project NePTWNE at Gannon University in Erie, Pennsylvania, told Newsweek. Project NEPTWNE aims to improve the quality of Lake Erie water.

She added that other research shows bottled water can contain high levels of microplastics and chemicals like benzene.

Tap water, she noted, is tested many times a day, while bottled water is tested far less often.

Despite the findings, researcher Richardson said she does not recommend switching from tap water to bottled water unless there is a known contamination issue.

"I think of all the plastic that gets into the environment from bottles," she said. "And, the cost is so much higher to buy bottled water."

More information

Washington State Department of Health has more on disinfection byproducts.

SOURCE: Newsweek, Jan. 16, 2026