Toxic ‘Forever Chemicals’ Detected in Drinking Water Supplies Across California

Drinking water sources for 74 community water systems serving 7.5 million Californians are contaminated with the highly toxic fluorinated chemicals called PFAS, according to an Environmental Working Group review of the latest state data.

Very low doses of PFAS chemicals in drinking water have been linked to an increased risk of cancer, reproductive and immune system harm, liver and thyroid disease, and other health problems. All of the detections in California water systems’ sources exceeded 1 part per trillion, or ppt, the safe level recommended by the best independent studies and endorsed by EWG.

More than 40 percent of the systems had at least one sample with a level of total PFAS over 70 ppt, the U.S. Environmental Protection Agency’s inadequate lifetime health advisory level for the two most notorious fluorinated chemicals, PFOA and PFOS. In addition to those two compounds, some California water systems detected up to six other PFAS chemicals.

Among the utilities with high maximum detections of PFAS in drinking water sources was the system for the southern part of Camp Pendleton, the sprawling Marine Corps base in San Diego County, where a combined concentration of 820 ppt for seven different PFAS chemicals was measured in a single well in 2017.

More than 578 ppt of eight PFAS chemicals was detected this year in a well of the City of Corona water system, and more than 450 ppt of six PFAS in a well of the California Water Service Company system for Oroville. In 2017, more than 400 ppt of six PFAS was found in a well of the California American Water Company system for Rosemont and other Sacramento suburbs.

See the full article on the Environmental Working Group's website here.

LAST UPDATED

October 21, 2024

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