California acts to limit pollutant targeted by Erin Brockovich
The California Environmental Protection Agency has issued the nation’s first public health goal for hexavalent chromium, the cancer-causing heavy metal made infamous after activist Erin Brockovich sued in 1993 to prove it had contaminated groundwater in the Southern California town of Hinkley.
At that time, the average hexavalent chromium levels in Hinkley's water was 1.19 parts per billion (ppb). The new state goal was set Wednesday at 0.02 ppb, judged to be the minimum amount of the element that poses a significant health risk in water, according to state officials.
That means for every million people who drink tap water with that level of hexavalent chromium, also called chromium 6, daily for 70 years, there is likely to be one additional case of cancer attributable to exposure to the metal, state officials said.
“As the nation’s first official goal for this contaminant, it will be an important tool that the Department of Public Health will use to develop a regulatory standard that will protect Californians from the health risks of chromium 6 in drinking water,” said Dr. George Alexeeff, acting director of the department’s Office of Environmental Health Hazard Assessment.
Chromium 6 occurs naturally in some drinking water, but often enters the water supply from industrial contamination, leaching from sites such as the disposal ponds of Pacific Gas & Electric's Topock Compressor Station in Hinkley. It can be removed using expensive reverse osmosis filters, but many people don't even know they're drinking it.
At least 74 million Americans in 42 states drink chromium-polluted tap water, much of it likely tainted with hexavalent chromium, according to studies by the nonprofit Oakland-based Environmental Working Group. They also found chromium 6 in tap water from 31 of 35 cities tested last year, with some of the highest levels in Riverside (1.69 ppb) and San Jose (1.34 ppb).
Environmentalists praised the new state goal, saying they hoped it would pressure state and federal officials to set new, enforceable standards for the metal and other drinking water contaminants.
California lawmakers passed legislation in 2001 requiring an enforceable drinking water standard for hexavalent chromium by 2004, but the requirement was never met (although the state did produce a timeline to show what they were doing).
California officials cautioned that the new state goal for was “not a regulatory level for cleanup of groundwater or surface water contamination,” meaning it cannot be used to justify investigations in places where residents suspect their water is making them sick, such as Hinkley or Kettleman City.
The national drinking water limit for chromium is 100 ppb, but water systems are not required to distinguish what percentage of chromium 6 versus other ions such as chromium 3 are contained in their drinking water, although U.S. EPA officials did recommend in January that water system officials start testing for chromium 6.
State officials said the new goal reflected recent research that showed young children were more susceptible to health risks from exposure to hexavalent chromium and other carcinogens. They noted that mice and rats that drank water containing high levels of the element developed gastrointestinal tumors, according to a 2007 study by the National Toxicology Program.
-- Molly Hennessy-Fiske
Photos, from top: An house stands empty in Hinkley in the path of a plume of groundwater tainted with hexavalent chromium; Erin Brockovich testifies before a state Senate committee in Sacramento in 2001 about tainted drinking water in Hinkley. Credits: Wally Skalij / Los Angeles Times; Robert Durell / Los Angeles Times