Last week I attended the EPA Listening Session for EPA's new-and-improved Draft Toxicological Review of Hexavalent Chromium. This is from the scientific experts at IRIS, the EPA's premiere Integrated Risk Information System, that provides top-notch scientific assessments of hazardous chemicals for use by regulators all over the country, and even the world, to set clean-up levels and exposure limits.
Hexavalent chromium is a highly hazardous industrial pollutant that is associated with several types of cancer, as well as damage to critical body organs and skin. The health harms it causes are permanent and irreversible. It has long been known to cause cancer when inhaled, and now there is sufficient evidence that ingestion of contaminated drinking water can also cause cancer, based on rodent studies conducted by the government National Toxicology Program. Importantly, dangerous uses of chromium are unnecessary, since good substitutes already exist for coatings, metal plating, pigments and dyes, and other uses.
The good news is that the new 2010 IRIS draft assessment has many health-protective improvements over the old 1998 assessment that is still up on the IRIS website. The new draft includes an oral reference dose (RfD) that is 3-fold more protective than the old one, and a first-time cancer risk estimate for drinking water exposures, based on evidence of cancer of the small intestine in rodent studies. The new draft is in agreement with the assessment of hexavalent chromium toxicity conducted by California Office of Environmental Health Hazard Assessment (OEHHA), which supports a proposed Public Health Goal (PHG) of 0.06 parts per billion (ppb) in drinking water.
The unfortunate news is that the chromium industry just isn't convinced yet. They need more evidence that drinking chromium-contaminated water is bad for you. So, they sponsored their own science, and then paid for it to undergo an 'independent' review. Apparently, a robust government (i.e. independent in real-life) study of rodents dying of small intestinal cancer after a lifetime of drinking chromium-laced water isn't good enough for those industry skeptics.
So, the industry ACC (American Chemistry Council) Hexavalent Chromium panel hired Tox Strategies, Inc to coordinate a series of studies, and have them reviewed by TERA. This is what they are calling "independent", although it is all paid for by the chromium industry. Moreover, the TERA representative at the listening session acknowledged that the industry sponsor has an opportunity to review all the studies before they are made public.
And, what did all this scientific independence conclude? Not surprisingly, that more study was required, more time, more science, and of course, that EPA should hold off on finalizing its draft until...well, until much much later, and maybe also in a galaxy far far away. More delay!
My favorite presentation by the industry at the IRIS listening session was the one where their paid experts analysed over 30 occupational studies and found almost no cases of small intestine cancer (Gatto et al, 2010). I pointed out that was probably because the workers were dying too fast from lung cancer from inhaling deadly levels of chromium in the air - no time to develop intestinal cancer from the bits that are swallowed. Sucks for the workers either way.
I was mildly nauseated by all of this, but really it's only what I've come to expect. IRIS staff scientists produce an assessment of a hazardous chemical, update the science, and provide an opportunity for public comment. The industry comes at them with a hundred reasons why the draft assessment should be delayed or denied. Industry hires scientists, funds research, and hires PR firms. So far, all well within the bounds of expected behavior.
But, this time I learned something that really bugged me. Remember the TERA peer review of the industry science, paid for by the industry? Well, turns out that one of the peer reviewers was an EPA staff scientist - a public servant, one of our guys (see page 11 of the TERA report)! In fact, at the IRIS Listening Session last week the TERA representative made a big deal about it, saying that by having EPA on their panel it sort of confirmed the independence of the process. No it doesn't! The process was paid by the chromium industry, so it is not independent. All it proves is that an EPA scientist acted inappropriately - how inappropriately will be determined once I receive a response to my Freedom of Information Request for documentation on the interactions.
The chromium industry attracted high level attention in 2006 from the Washington Post, LA Times, and USAToday for its intentional manipulation and obfuscation of data to deny the health harms of breathing chromium-contaminated air. A published documentation of these efforts reported that, “Faced with the threat of stronger regulation, the chromium industry initiated an effort to challenge the scientific evidence supporting a more protective [OSHA workplace] standard [for inhalation]. This effort included the use of "product defense" consultants [Exponent and ChemRisk] to conduct post hoc analyses of a publicly-funded study to challenge results viewed unfavorably by the industry” (Michaels et al, 2006).
It shouldn’t come as any surprise then to find that three years earlier, in 2003, the same two product defense consultant groups published an article finding no significant health risks from drinking chromium-contaminated water (Paustenbach et al, 2003; Proctor et al, 2002). Their article concluded that, “exposure to Cr(VI) in tap water via all plausible routes of exposure, at concentrations well in excess of the current U.S. Environmental Protection Agency (EPA) maximum contaminant level of 100 μg/L (ppb), and perhaps those as high as several parts per million, should not pose an acute or chronic health hazard to humans” (Paustenbach et al, 2003).
Haven't we heard enough baseless protestations and unsupported claims from this industry and its representatives?
Good job, EPA IRIS staff! Now, it is time to move ahead and finalize the assessment, and then get on with health-protective regulations.