According to a new report from the Environmental Working Group, there may be cancer-causing products in tap water.
Researchers said they found 22 carcinogens in tap water, including arsenic, uranium and radium.
The group said there may be a health risk even though most tap water meets the legal standards put in place by the federal government.
The combination of chemical pollutants in U.S. drinking water could result in more than 100,000 cancer cases, according to the study, which was published in the journal Heliyon.
"Drinking water contains complex mixtures of contaminants, yet government agencies currently assess the health hazards of tap water pollutants one by one," said Sydney Evans, lead author of the paper and a science analyst at EWG. "In the real world, people are exposed to combinations of chemicals, so it is important that we start to assess health impacts by looking at the combined effects of multiple pollutants."