Study: Drinking California tap water over lifetime could increase cancer risk

A new study released Tuesday by an environmental advocacy group claims that drinking California tap water over the course of a lifetime could potentially increase your risk of cancer. 

The study, released by the Environmental Working Group, claims the increased risk is due to contaminants found in public water systems in California. The greatest risks found in the water were from arsenic, byproducts of disinfectant chemicals, radioactive elements like uranium, and hexavalent chromium, or chromium-6, the notorious “Erin Brockovich” chemical. 

"The array of toxic pollutants in California drinking water could in combination cause more than 15,000 excess cases of cancer," EWG said in a press release.

According to EWG, most U.S. drinking water systems meet all state and federal legal limits. In California, 90 percent of systems met all federal standards for the past seven years, according to the state’s Safe Drinking Water Information System.

"But legal doesn’t always mean safe," the report said. "Legal limits are based on economic and political considerations that usually don’t reflect the lower levels that scientists have found pose health risks. Indeed, over 85 percent of the cancer risk calculated in the EWG study is due to contaminants that were below legal limits."

EWG has created a "Tap Water Database" to help individuals and families ensure that they are drinking the cleanest, safest water possible. If harmful contaminants were found in your water, even at levels below the federal legal limits, EWG highly recommends filtering your water.