California: 15,000 cancer cases could stem from chemicals in tap water

(CNN) A new study finds that drinking tap water in California over the course of a lifetime could increase the risk of cancer.

Researchers from the environmental advocacy group Environmental Working Group estimated that the contaminants found in public water systems in California could contribute to about 15,500 cancer cases there over the course of a lifetime. These contaminants include chemicals such as arsenic, hexavalent chromium and radioactive elements such as uranium and radium. The study was published Tuesday in the journal Environmental Health.

"We need to look at contaminants as a group — not just one at a time. It’s more important to analyze co-occurring contaminants to understand the real world exposure," said lead author Tasha Stoiber, a senior scientist with EWG. She explained that cancer risks are typically determined at the individual element level.

Stoiber and her colleagues evaluated 2,737 different public water systems across the state of California by assessing the level of reported contaminants in the systems. These water systems are the main providers of drinking water in California, serving 98% of the state’s population. They are regulated by the federal Safe Drinking Water Act and overseen by state regulators.

Water systems test for a […]

Full article: Study estimates 15,000 cancer cases could stem from chemicals in California tap water