Perchlorate and chromium are on EPA's bucket list of 'toxic chemicals'

EPA Goes After Perchlorate and Chromium: The Media Follow Along Without Questioning

By —— Bio and Archives--February 10, 2011

Global Warming-Energy-Environment | Comments | Print Friendly | Subscribe | Email Us

Perchlorate and chromium are on EPA’s bucket list of ‘toxic chemicals’ on which it proposes to set new limits. Neither has been given fair coverage by the main-stream media. Quotes can be found from environmental groups supporting the action, but nothing from scientists and others with an opposing view, typical of the unbalanced reporting that has covered the perchlorate and chromium issues.



The scientific literature is rife with reports overwhelmingly pointing to the conclusion that perchlorate levels do not need to be changed, but these have been ignored by the press including The New York Times, The Wall Street Journal and The San Francisco Chronicle. (1-3)

Scientists have reported that thyroid function problems are only produced at doses more than an order of magnitude greater than the 5 to 20 parts per billion levels generally found in groundwater in the southwestern US. (4) A report by the National Academy of Sciences agrees with these numbers (5), and this conclusion has been supported by six additional studies. (6-8)

Want something to worry about besides that fact the Mother Nature naturally produces perchlorate and it can be found about anywhere?

  • A serving of spinach inhibits iodine absorption in the thyroid gland 300 times more than one part per billion of perchlorate someone might consume by drinking two quarts of groundwater.(9)
  • One serving of rhubarb has about 10 times as much iodine absorption interference as perchlorate and one serving of turnip greens 10 times. (10)

Wayne Lusvardi observes, “It appears more and more that perchlorate may not be a health or environmental scandal but a moral scandal of putting billions of dollars of our resources on the wrong health priority.” (9)

Are you aware that perchlorate has been found on Mars? Some researchers speculate that perchlorate properties have implications for the possible habitability of the Martian subsurface. As an article in the prestigious science journal Nature concludes: If you want to fuel speculation, rather than rockets, the possibility of liquid water and microbe food on Mars is about as good as it gets.” (11)

Interesting isn’t it? On Earth folks are raising a fuss about perchlorate while now that it’s been found on Mars it’s suggested as a possible mechanism for life on that planet at one time.


Hinkley, California, the town made famous in the Oscar-winning Julia Roberts movie Erin Brockovich, does not show any evidence of an increased rate of cancers This was reported by a few media outlets on December 13, 2010. (12,13) One would have thought this was good news and should have been covered more widely. But the fact that it was good news, means it was not news. You would think this would be cause for celebration—no cancer clusters, no cancers above expected limits—but not so. In fact, Erin Brochovich is back in Hinkley pursuing claims about a return of the chromium plume. (12)

Then a strange thing happened a week later. On December 20, a number of major media outlets headlined a study that found ‘cancer-causing chromium in tap water.’ The New York Times was prominent in the coverage. (14)

Some background- Hinkley is the place where Erin Brockovich successfully took PG&E to court forcing it to pay a record $333 million class-action settlement because it was determined that the company allowed a toxic plume of hexavalent chromium (Cr6) to be released from a natural gas pipeline.

Recently, the California Cancer Registry reported on three studies that show cancer rates remained normal from 1988 to 2000. From 1996 to 2008, cancers in Hinkley were 12.5% below the state average. (13)

All of the above news about less cancers in Hinkley, was reported on December 13 but as mentioned earlier this was mostly ignored. Then a timely event happened on December 20. This time The New York Times joined the fray with the headline. “Probable Carcinogen Found in Tap Water of 31 US Cities.” They discussed a report by the Environmental Working Group (EWG) that said drinking supplies in 31 of 35 cities tested contained some level of Cr6, and 25 contained higher levels than the California goal of 0.06 parts per billion. (14) Dr. Robert Baratz, an expert on metal exposure who teaches at the Boston University and Tufts University Schools of Medicine, questions drawing valid scientific conclusions from the single samples EWG took from water taps in a variety of cities. (15)

The EWG study reported that chromium caused cancer in laboratory mice and rats. In spite of this, Cr6 has never been shown to be carcinogenic to humans in any degree when dissolved in drinking water. The only cancer that can be attributed to Cr6 is with workers who inhaled massive amounts over many years. The EPA oral reference dose (RfD) for Cr6, which includes a monster safety factor of 300, is way above the levels of Cr6 detected by the EWG. (16)

Deborah Proctor reports in the Journal of Toxicology and Environmental Health, “The preponderance of evidence from recent epidemiological studies of Cr6—exposed workers does not support an increased risk of cancer outside of the respiratory system; studies of four environmentally exposed populations are negative; there is only one lifetime animal feeding study, and the findings from that study are considered to be flawed and inconclusive. In short, at concentrations at least as high as the current US maximum contaminant level (100 parts per billion), and probably at least an order of magnitude higher, Cr6 is reduced to Cr3 prior to or upon systemic absorption. The weight of scientific evidence supports that Cr6 is not carcinogenic in humans vie the oral route of exposure at permissible drinking-water concentrations.” (17)

Chromium is present in many foods: those that contain the most chromium, more than 300 parts per billion, are oysters, calf’s liver, egg yolk, peanuts, grape juice and black pepper. Many commonly eaten foods have some chromium, such as potatoes (18 ppb), beans (9 ppb), carrots (18 ppb) and apples (8 ppb). (18)

Tobacco has been reported to contain up to around 5,000 ppb hexavalent chromium. (19)

So EPA continues on its merry way to impose unnecessarily stringent regulations with the help of an unquestioning media.


  1. John M. Broder, “EPA Plans First Rules Ever On Perchlorate in Drinking Water,“greenblogs.nytimes,com, February 2, 2011
  2. Siobhan Hughes, “EPA seeks new limits on chemicals in drinking water,” The Wall Street Journal, February 3, 2011, Page A7
  3. Kelly Zito, “EPA to regulate harmful chemical in drinking water,” The San Francisco Chronicle, February 3, 2011, Page A6
  4. M. A. Greer, et al., “Health Effects Assessment for Environmental Perchlorate Contamination: The Dose Response for Inhibition of Thyroidal Radioiodine Uptake in Humans,” Environ. Health Perspect., 110, 927, 2002
  5. National Academy of Sciences, Health Implications of Perchlorate Ingestion, The National Academies Press, Washington, DC, 2005
  6. R. Penner, “Perchlorate report doesn’t dispel controversy,” Environ. Sci. Technol., 39, 96A, 2005
  7. R. Tarone et al., “The epidemiology of environmental perchlorate exposure and thyroid function: a comprehensive review,” J. Occup. Environ. Med., 52, 653, June 2010
  8. P. Buffler et al., “Thyroid function and perchlorate in drinking water: an evaluation among California newborns,” Environ. Health Perspec., 114, 798, May 2006
  9. W. Lusvardi, “News coverage of perchlorate issues is thirty miles wide but only one inch deep,” chronwatch.com, May 4, 2005
  10. R. B. Belzer et al., “Using Comparative Exposure Analysis to Validate Low-Dose Human Health Risk Assessment: The Case of Perchlorate,” in Comparative Risk Assessment Decision Making, NATO, United Nations, New York, NY, 2004, p11
  11. Eric Hand, “Strange brew,” Nature, 456, 692, December 11, 2008
  12. Tim Cavanaugh, “Erin Brockovich” Town Shows No Cancer Cluster,” Reason Magazine, December 13, 2010
  13. Warner Todd Huston, “No Cancer in Hinkley, California: Activist Hollywood Wrong AGAIN!”, Canada Free Press, December 16, 2010
  14. Elana Schor, “Probable Carcinogen Found in Tap Water of 31 US Cities,” The New York Times, December 20, 2010
  15. Eliza Barclay, “Some Scientists Skeptical of Report On Chromium In Drinking Water,” NPR’s Health Blog, December 22, 2010
  16. Steve Milloy, “EWG pulls an ‚ÄòErin Crockovich”, junkscience.com, December 20, 2010
  17. Deborah M. Proctor, “Is Hexavalent Chromium Carcinogenic Via Ingestion? A Weight-of-Evidence Review,” Journal of Toxicology and Environmental Health, Part A, 65, 701, May 2002
  18. John Emsley, Nature’s Building Blocks, (Oxford, Oxford University Press, 2001), 111
  19. Tor Norseth, “the Carcinogenicity of Chromium,” Environ. Health Perspec., 40, 121, 1981


Only YOU can save CFP from Social Media Suppression. Tweet, Post, Forward, Subscribe or Bookmark us

Jack Dini -- Bio and Archives | Comments

Jack Dini is author of Challenging Environmental Mythology.  He has also written for American Council on Science and Health, Environment & Climate News, and Hawaii Reporter.

Commenting Policy

Please adhere to our commenting policy to avoid being banned. As a privately owned website, we reserve the right to remove any comment and ban any user at any time.

Comments that contain spam, advertising, vulgarity, threats of violence and death, racism, anti-Semitism, or personal or abusive attacks on other users may be removed and result in a ban.
-- Follow these instructions on registering: