A study released Monday by the Environmental Working Group, a nonprofit research and advocacy organization, found hexavalent chromium in tap water from 31 cities, including Chicago’s Lake Michigan water available to the Chicago and suburbs. The study tested 35 cities. The highest levels were discovered in Norman, Oklahoma; Honolulu, Hawaii; and Riverside, California. The Lake Michigan water level of hexavalent chromium (Chromium 6 or Chromium VI or Cr-6) was measured at 0.18 parts per billion (ppb), which was also the average level of the 35 cities tested. The Average Cr-6 levels in Hinkley, California, famous in the motion picture film Erin Brockovich, were recorded as 1.19 ppb with a peak of 3.09 ppb. The Pacific Gas and Electric Company (PG&E) Topock Compressor Station, where Cr-6 was used to prevent rust in machinery, averaged 7.8 ppb and peaks at 31.8 ppb based on the PG&E Background Study. California’s proposed health goal for drinking water is .06 ppb, which puts Lake Michigan water at three times the safety limit proposed last year by California officials.
City Population Cr-6 Level
Norman, Oklahoma 89,952 12.90 ppb
Honolulu, Hawaii 661,004 2.00 ppb
Riverside, California 280,832 1.69 ppb
Madison, Wisconsin 200,814 1.58 ppb
San Jose, California 979,000 1.34 ppb
— EWG, Environmental Working Group
PG&E wastewater dissolved the hexavalent chromium from the cooling towers and was discharged to unlined ponds at the site. Some of the wastewater percolated into the groundwater, affecting an area near the plant approximately two miles long and nearly a mile wide. The case was settled in 1996 for USD $333 million, the largest settlement ever paid in a direct action lawsuit in US history.
In response to a new study that found cancer-causing hexavalent chromium in tap water from Chicago and 30 other cities, Illinois Senators. Mark Kirk and Dick Durbin are demanding to know what the EPA and federal regulators plan to do about contamination from the toxic metal.
Durbin, the assistant Senate majority leader, and Kirk, the state’s newly elected senator, plan to meet Tuesday with U.S. Environmental Protection Agency Administrator Lisa Jackson to discuss Chromium-6 levels.
EPA scientists originally thought stomach digestion reduced Chromium-6 to a harmless variant of Chromium, Chromium-3, an essential nutrient. Recently the EPA has become increasingly concerned about hexavalent chromium. Chicago and the other cities are not required to test for chromium-6. Currently, the EPA does not limit chromium-6 levels in drinking water. The EPA now only limits total chromium content, which includes another form of the metal, chromium-3
Critics say federal rules, last updated in 1992, need to be strengthened to reflect new science that shows drinking water contaminated with chromium-6 can cause stomach cancer. The EPA now only limits total chromium content, which includes another form of the metal, chromium-3, an essential nutrient. The Maximum Contaminant Level (MCL) currently set by the United States Environmental Protection Agency(EPA) for TOTAL Chromium is 0.10 ppm (PARTS PER MILLION).
Hexavalent chromium (chromium VI) refers to chemical compounds that contain the element chromium in the +6 oxidation state. Hexavalent chromium is transported into cells via the sulfate transport mechanisms, taking advantage of the similarity of sulfate and chromate with respect to their structure and charge. Trivalent chromium (chromium-3), which is the more common variety of chromium compounds, is not transported into cells.
The Environmental Working Group (EWG) is an environmental organization that specializes in environmental research and advocacy in the areas of toxic chemicals, agricultural subsidies, public lands, and corporate accountability. EWG is a non-profit organization.
Every year the Environmental Working Group publishes its famous “Dirty Dozen” list of the most pesticide-infested foods that should always be bought organic by consumers.
According to EWG, The National Toxicology Program has concluded that hexavalent chromium (also called chromium-6) in drinking water shows “clear evidence of carcinogenic activity” in laboratory animals, increasing the risk of gastrointestinal tumors. In September 2010, a draft toxicological review by the U.S. Environmental Protection Agency (EPA) similarly found that hexavalent chromium in tap water is “likely to be carcinogenic to humans.”
See also …
Environmental Working Group — ewg.org