Hexavalent chromium is best known as the chemical compound at the center of Erin Brockovich's 1993 lawsuit against PG&E, which resulted in a $333 million settlement. The chemical had contaminated drinking water supplies in Hinkley, Calif.
The complaint, citing DPH studies, claims that "at least one-third of drinking water sources sampled statewide ... are contaminated with hexavalent chromium at concentrations higher than those" state officials have deemed safe.
San Jose's water supply, the suit notes, is "one of the five" most contaminated cities among those tested.
The environmental groups base this assessment on the California Office of Environmental Health Hazard Assessment, which sets a "public health goal" for hexavalent chromium at .02 parts per billion and classifies that chemical as a carcinogen (through both inhalation and consumption). The public health goal, according to the COEHHA, is intended as an "estimate of the level of a contaminant in drinking water that is not anticipated to cause or contribute to any adverse health effects, or that does not pose any significant risk to health." Some studies have suggested that chronic consumption of the chemical increases the risk of cancer.
DPH tests over the years, though, have taken thousands of drinking water samples that exceed this mark, with hundred containing as much a 1.0 parts per billion, according to the suit. But because the department has not yet set "maximum contaminant levels," these water supplies cannot be officially ruled as unsafe.
The environmental groups allege that the department has not dedicated enough resources toward regulating hexavalent chromium.
Not that California's standards are necessarily outdated. The Environmental Protection agency has not set federal drinking water standards for the compound either.