California Office of Environmental Health Hazard Assessment
could lower the 6 parts per billion standard
Morgan Hill – State health officials may revisit the “public health goal” for perchlorate in drinking water after reviewing recent research that shows even minute traces of the rocket-fuel chemical lowers essential thyroid hormones in women causing metabolic problems and neurological damage to fetuses.
The study, released in October by the Centers for Disease Control and Prevention, is under review at the California Office of Environmental Health Hazard Assessment.
Based on that review, the environmental agency could lower the 6 parts per billion standard it set in 2004, said spokesman Alan Hirsch.
“This is a very important study,” Hirsch said, adding a full-scale review of the public health goal would likely take a year to complete. “The department would have to put together a whole new document, hold public review and peer review from independent scientists.”
The decision could affect the longevity of a “Maximum Contamination Level” being forged by the California Department of Health Services. The state cannot legally set the MCL lower than the public health goal.
“Our number one goal is to get a safe drinking water standard out there. What we don’t want to do is delay the process,” said Patti Roberts, a spokeswoman for the California Department of Health Services. “But we can go back and revisit the standard if (the Office of Environmental Health Hazard Assessment) changes the public health goal.”
A public comment period on the proposed MCL of 6 ppb ended Nov. 3. The regulation could be adopted in February 2007, Roberts said.
In July, Massachusetts set the nation’s first drinking water standard for perchlorate of 2 ppb.
Santa Clara Valley Water District Director Rosemary Kamei said there is too much evolving research to assume 6 ppb is a safe long-term standard for Californians.
“I’d rather err on the side of being more conservative than liberal when it comes to health effects,” Kamei said.
The Centers for Disease Control and Prevention study found a significant link between exposure to perchlorate at levels as low as 3 ppb and reduced thyroid levels in women.
Assemblyman John Laird, D-Santa Cruz, in October encouraged the California Department of Health Services to act quickly should a lower public health goal be established in the future. In a letter to the department, he also applauded efforts to set a 6 pbb standard “considering the lengthy delay.”
Sylvia Hamilton, chair of the Perchlorate Community Advisory Group, which advises water officials on matters relating to a 10-mile plume of perchlorate-contaminated groundwater stretching south from Olin Corporation’s road flare plant in Morgan Hill, also hopes new research leads to a stricter standard in California.
As to Olin’s obligation to meet the Regional Water Quality Control Board’s cleanup and abatement order, which requires cleanup to a level of “background,” Laird and Hamilton each indicated the new MCL may play a role in improving the groundwater monitoring requirements for the contaminated area.
“You’re supposed to clean up the water to where it was before the contamination took place,” Hamilton said. “But this would set upper limits.”
A revised cleanup plan from Olin is due Dec. 6.
Tony Burchyns covers Morgan Hill for The Times. Reach him at (408) 779-4106 ext. 201 or tburchyns@morganhilltimes.
