State Moves to Control Chromium 6

Two state agencies announced Tuesday they will develop a specific standard for chromium 6 in drinking water, breaking with their previous policy of regulating the suspected carcinogen indirectly by setting limits on total chromium.

The action came after well-water surveys showed that chromium 6 was appearing in much higher concentrations than officials had anticipated, said David Spath, drinking water chief for the state Department of Health Services.

“A total chrome standard doesn’t make a lot of sense because it includes chromium 3, which is an essential nutrient and not a health risk in the levels we see in water,” Spath said. “It makes more sense to focus on chromium 6, which is the chemical of concern.”

The separate standard for chromium 6 was proposed jointly by the Department of Health Services and the state Office of Environmental Health Hazard Assessment. Spath said the standard would be the first in the nation for chromium 6, a chemical used in paint pigments and manufacturing processes such as chrome-plating.

Chromium 6 has been detected in water systems throughout the state, including industrial areas of Los Angeles and the San Fernando and San Gabriel valleys. Scientists say the chemical is a known carcinogen when inhaled as a vapor, but disagree over safe limits when it is ingested in water.

To address that issue, the California Environmental Protection Agency announced Tuesday that the University of California will convene at its request a panel of expert scientists from throughout the country to review the health hazard posed by chromium 6 when ingested in water.

California currently limits total chromium to 50 parts per billion. Two years ago, the Office of Environmental Health Hazard Assessment asked the state Department of Health Services to slash that level to 2.5 ppb, saying the tougher standard is needed to ensure optimum safety.

The OEHHA recommendation was based on an assumption that chromium 6 makes up about 7.2% of total chromium in water. But in reviewing that request, DHS officials conducted a survey that found chromium 6 comprised, on average, “more than 50% of total chromium,” state DHS Director Diana M. Bonta said in a memo Tuesday to OEHHA Director Joan Denton.

“Subsequent testing done by local water agencies, particularly in the Los Angeles area, appears to confirm the department’s finding,” Bonta wrote.

The DHS survey found:

* In Daly City near San Francisco, chromium 6 comprised 67% to 100% of total chromium, at levels of up to 28 ppb.

* In Davis, chromium 6 made up between 44% and 94% of total chromium sampled, at levels of up to 34 ppb.

* In the Los Angeles County communities of Arcadia, La Puente and San Gabriel, chromium 6 comprised between 58% and 85% of total chromium (that survey did not include the parts per billion).

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An OEHHA official said the discrepancy between their initial scientific assumptions and recent test results can be explained by a lack of studies focused on chromium 6.

“The 7.2% figure for chromium 6 was the best available number when we were putting together our public health goal back in 1998 and and there’s definitely more information about its prevalence in water now,” said OEHHA spokesman Allan Hirsch. “We’ve been open about the fact that there was very little data on this when we started three years ago.”

A new standard for chromium 6 is expected to be adopted by 2004, Spath said.

State Sen. Deborah Ortiz, (D-Sacramento), who had introduced legislation calling for a separate standard, applauded the action.

“This is what we had asked for, to make this a priority,” Ortiz said, “to help us gather the data and the scientific information necessary to make sound policy decisions.”

The state is also waiting for the results of an extensive study of chromium 6 being conducted in the San Fernando Valley in the wake of legislation (SB 2127) signed last year by Gov. Gray Davis. The bill was triggered by Times stories detailing delays in acting on the OEHHA recommendation.

In addition to calls for tighter chromium standards on the state level, U.S. Sens. Barbara Boxer (D-Calif.) and Dianne Feinstein (D-Calif.) have called on the U.S. Environmental Protection Agency to tighten federal standards for chromium from its standard of 100 ppb.

Alexis Strauss, director of the federal EPA’s water division, said the agency supports the state’s effort to come up with a separate standard for chromium 6 and to reassess its health threat.

“I think it’s a positive step,” Strauss said. “We need to address this matter, which is of such a concern in Southern California. And I trust that through this process a consensus will emerge.”