Two major environmental groups have filed suit against the California State Department of Public Health for what they call a failure by the state to set rules for the safe amount of a toxic chemical in drinking water. Hexavalent chromium, also known as chromium-6, gained widespread attention as the chemical that sickened residents in the film Erin Brockovich.
The Natural Resources Defense Council and the Environmental Working Group claim that the state missed a 2004 deadline imposed by the Legislature for establishing a maximum limit on how much of the pollutant can exist in drinking water without endangering public health. The suit was filed today in Alameda Superior Court and claims the delay is unjustified. In 2011, the California Environmental Protection Agency issued a public health goal of less than 0.02 parts per billion for chromium-6 in drinking water.
According to a 2011 report by the state’s Water Resources Control Board, Los Angeles, San Bernardino and Fresno Counties have the highest occurrences of chromium-6 pollution in the state. Of the 6,565 water sources surveyed by the state, 3,107 of them showed instances of chromium 6 above the threshold required for reporting.
The Water Resources Control Board describes the health effects of hexavalent chromium as follows:
Hexavalent chromium is known to cause cancer in humans when inhaled. Hexavalent chromium can also damage the lining of the nose and throat and irritate the lungs. A number of scientific studies have found elevated rates of lung cancer in workers with occupational exposure to hexavalent chromium by inhalation. A few studies of workers exposed to hexavalent chromium by inhalation have shown an increase in cancers of the gastrointestinal tract. When swallowed, hexavalent chromium can upset the gastrointestinal tract and damage the liver and kidneys. In recent scientific studies of laboratory animals, hexavalent chromium has been linked to cancer when ingested, although ingested hexavalent chromium is rapidly converted to Cr 3 after entering the stomach and contact with organic matter.
Common sources of chromium pollution include discharges from dye and paint pigments, wood preservatives, chrome plating operations, and leaching from hazardous waste sites.