Study finds chromium 6 in tap water throughout U.S.

A study of tap water released Monday shows that chromium 6 is found in water throughout much of the nation, but naturally occurring or background levels of the chemical are higher in Hinkley than most of the areas studied.

Detectable levels of chromium 6 were found in tap water in 31 of 35 cities within the United States in a study done by the non-profit organization Environmental Working Group. The study looked at tap water within major cities in the United States, as well as areas that had previously shown high levels of total chromium.

Total chromium includes chromium 6 as well as chromium 3. Chromium 6 is known to cause cancer when inhaled and studies have shown that large amounts of ingested chromium 6 cause tumors in rats and mice. Chromium 3 is considered to be an essential nutrient when taken at low levels.

The natural or background levels of chromium 6 in Hinkley are 3.1 parts per billion, which is higher than most of the levels found in the study. The only area in the study found with higher levels of chromium 6 was Norman, Okla.

All four California cities studied by Environmental Working Group had detectable levels of chromium 6 within tap water tested by scientists. The study showed that Riverside had the third highest levels of chromium 6 in its tap water. Los Angeles, San Jose and Sacramento also showed levels of chromium 6 above the proposed public health goal for the state of California.

Environmental Working Group is a nonprofit organization which specializes in environmental research and advocacy in the areas of farming, toxic chemicals, natural resources and energy. The organization states that most of its funds come from grants donated by foundations.

Even the lowest levels found in the study of California would still be over twice the proposed public health goal for the state if approved.

The Office of Environmental Health Hazard Assessment of the California Environmental Protection Agency has proposed a public health goal of .06 ppb of chromium 6 for drinking water. If the public health goal is approved, it would be the first step toward an enforceable maximum contaminant level.

California would be the first state to have any type of public health goal for chromium 6 by itself. Currently, the federal EPA has a maximum contaminant level of 100 parts per billion of total chromium.

Although Environmental Working Group states that part of the purpose of the study is to get the federal Environmental Protection Agency to set a maximum contaminant level for chromium 6, one organization feels that worries about chromium 6 are overstated.

Dr. Gilbert Ross, Medical Director of The American Council on Science and Health, said he felt Environmental Working Group is trying to worry people unnecessarily about chromium 6. He cited a recent study done by California Cancer Registry epidemiologist Dr. John Morgan, which showed that cancer rates in Hinkley were actually below the expected numbers for areas with similar demographics.

ACSH states that it is a consumer education consortium concerned with issues related to food, nutrition, chemicals, pharmaceuticals, lifestyle, the environment and health. The council consists of a board of 350 doctors, scientists and policy advisors. Although ACSH is a nonproft group, it has been criticized in the past because the organization receives a portion of their funding from corporations.

The chromium 6 contamination in Hinkley began in the 1950s when Pacific Gas and Electric used chromium 6 in cooling tower water in order to prevent rusting in its compressor station in Hinkley. The water was released into unlined ponds at the site, where it slowly seeped into the groundwater. The plume of contaminated water is now about 2 miles long and nearly a mile wide. PG&E has been ordered by the Lahontan Regional Water Quality Control Board to stop the spread of the chemical and reduce it to background levels.

The contamination in Hinkley became famous as a result of legal aid Erin Brockovich’s groundbreaking settlement for $333 million against PG&E. Julia Roberts played Erin Brockovich in an Oscar-winning film produced in 2000 about the settlement.

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