Study Finds California Tap Water May Increase Cancer Risk

CNN recently reported on findings from an Environmental Working Group study that revealed “contaminants found in public water systems in California could contribute to about 15,500 cancer cases”.

The main takeaway from this report was that it’s not just the presence of one specific contaminant in California’s tap water, but multiple contaminants together that increase this risk.

The study looked at 2,737 water systems in California, which serve approximately 98 percent of the state. Some of the water contaminants mentioned in the article include arsenic, hexavalent chromium, uranium, and radium.

Here are some additional stats from the report:

  • 1 in 1,000 was the cancer risk for people being served by water systems deemed to be in the “highest risk” category
  • 495 water systems in California were found to be in the “highest risk” category
  • 4,860 cancer diagnosis were estimated to come from people drinking water from the “highest risk” systems over the course of a lifetime
  • 47% of estimated lifetime cancer cases were due to arsenic pollution in drinking water

So what should homeowners living in California (or other areas) who are worried about tap water contamination do to protect themselves?

In the article, Environmental Working Group senior scientist Tasha Stoiber suggests taking steps like adding a certified filter to reduce exposure. The article notes:

“Filters should be targeted to the contaminants and can either be applied right where consumers use their water, like a faucet filter or water pitcher, or a large whole house system that treats water as it enters the house.”