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

Research conducted by the environmental advocacy group Environmental Working Group estimated that about 15,500 cancer cases in California were the direct result of contaminants found in public water systems. Much of the cancer risk was driven by an unsafe level of arsenic, which occurs naturally in groundwater. Even very low levels of arsenic can be highly carcinogenic. To read the full article, click here.