The Los Angeles Times
Monday 26 November 2007
A House committee says an agency lapsed by not assessing health damage from solvent pollution in Southern California aquifers.
A House committee is demanding to know why federal regulators failed to assess potential public health damage from extremely high levels of a toxic industrial solvent found in Southern California drinking water before the mid-1980s.
Trichloroethylene, widely used in the defense industry, was discovered in aquifers under the San Gabriel and San Fernando valleys, which supplied drinking water to nearly 2 million residents. Across the nation, the chemical is one of the most widespread water contaminants.
A letter sent today to the chief of the Agency for Toxic Substances and Disease Registry by the House Energy and Commerce Committee said the agency failed to conduct the recommended health evaluations in communities across the nation, an apparent lapse that went unnoticed for more than a decade.
"We are concerned that the agency has failed to complete or act on health recommendations and studies," Rep. Joe Barton (R-Texas), ranking member of the committee, wrote to Julie Louise Gerberding, administrator for the agency.
Trichloroethylene, or TCE, is classified as a carcinogen by California's Environmental Protection Agency and some international agencies. It is suspected that residents of dozens of Southern California communities from Burbank to West Covina were exposed for an unknown number of years to levels of TCE hundreds or even thousands of times above the current federal drinking-water standard of 5 parts per billion.
By the early 1990s, the California Department of Health, working jointly with federal authorities, recommended that a health assessment be conducted to measure whether past contamination had significantly affected the health of residents, according to a series of documents unearthed by the House Energy and Commerce Committee.
Barton's staff believes that an exhaustive health review could alert residents who might have been contaminated to get annual health screening and that early medical intervention could save significant numbers of lives.
The Agency for Toxic Substances and Disease Registry is part of the Centers for Disease Control and Prevention in Atlanta - the main federal agency for epidemiological studies of diseases in the general public.
"The most important recommendation was to minimize exposure, to make sure people had safe water," said agency spokeswoman Dagny Olivares. "Because exposures were reduced or eliminated as the contamination was found, [the agency] felt that public health was being protected."
Any retrospective examination of health damage would be difficult, she said. Barton's office, however, said the toxic-substances agency is conducting a multiyear program to assess the health of veterans who served at Camp Lejeune in North Carolina, where tens of thousands of Marines were exposed to TCE. It has found evidence of elevated instances of leukemia.
If the agency can do that for the Marines and their families in North Carolina, Barton's staff believes that it should also be conducting such assessments for other military bases and civilian populations.
Olivares said that at Camp Lejeune, contamination researchers "had detailed information on the population, including who was exposed and who was not exposed, and we were able to measure specific health outcomes of interest among these individuals. This type of information is not available for the San Fernando or San Gabriel sites."
The site reviews and recommendations found by Barton's staff are dated from 1992 and 1993. They say that "people were probably exposed to . . . contaminated ground water before 1980" and recognized "the public health need to evaluate possible past exposure" in the case of the San Fernando Valley. Another site review for the San Gabriel Valley recommends: "Conduct a health consultation consisting of a retrospective assessment of exposure to groundwater contaminants prior to 1979."
TCE has been enveloped in growing controversy over the last few years as evidence mounts that it causes cancer. It is the most widespread water contaminant in the nation, affecting hundreds of military bases, aerospace centers, government laboratories and general industrial sites.
The U.S. Environmental Protection Agency abandoned in 2003 a draft health risk assessment that found that the chemical was many times more carcinogenic than earlier thought.
The matter was sent to the National Research Council for an exhaustive review. Last year it issued a 379-page report that found increasing evidence that TCE does cause cancer and advised the EPA to complete its earlier health risk assessment.
Dr. David M. Ozonoff, a Boston University TCE expert, has long argued that federal regulators were not properly recognizing the cancer risk of TCE. But Ozonoff said he was far from certain that it would be possible to conduct a broad epidemiological study in Southern California.
"It would be pretty hard, logistically," Ozonoff said. "You would have to go back and create a list of a million people and then find them and then follow their health for 10 years. It would be incredibly difficult and costly."
Another major question is whether screening and early medical intervention could save lives, he added. TCE is associated with kidney cancer, leukemia and non-Hodgkin's lymphoma, which are difficult to detect early, he said. Still, California has some of the biggest TCE contamination sites.
More than 30 square miles of the San Gabriel Valley, about 18% of it, lie in one of four Superfund sites in which the main contaminants are TCE and its close chemical cousin perchloroethylene, a dry-cleaning agent. Much of the contamination was traced to defense contractors.
The contaminated aquifer supplies water for about 1 million residents, though it now meets the federal limit of 5 parts per billion. A cleanup over the last 20 years has cost more than $120 million and will continue for decades. The operation pumps and filters 37 million gallons of polluted water at Whittier Narrows every day.
The San Fernando Valley is also over a large TCE plume grouped into three separate Superfund sites that have cost more than $150 million to clean up so far. The plume extends 4 miles and contaminates water for 800,000 residents. The 1992 evaluation found that the highest concentration of TCE in a well was 18,000 parts per billion.
Much of the pollution was traced to the former Lockheed Martin facilities in Burbank. Litigation in the 1980s and 1990s, in which residents claimed they were poisoned, was settled out of court or dismissed.
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