Dec 6, 2012

Further thoughts about NRDC, ACSH, and environmental cancer

Adam M. Finkel, Sc.D. - I don’t know why (I could make an informed guess, but that would distract from the science-policy discussion) Gilbert Ross woke up on the wrong side of the cot the other day and disgorged his shrill post about NRDC’s “crackpot” theories of cancer causation.  I do know, however, that nothing in Jennifer Sass’ actual blogpost (http://switchboard.nrdc.org/blogs/jsass/we_wont_prevent_cancer_until_w.html) is untrue or even reasonably controversial. 

Other than an unremarkable recitation of the well-documented efforts of groups (who also fund Ross’s ACSH) to lobby against stronger regulation of toxic chemicals, Sass made the following statement about the cancer burden, in light of the Nature editorial pointing out that we will certainly fail to “cure breast cancer by 2020”:  “We will BEGIN to beat back cancer when we reduce, control and eliminate the industrial chemicals that cause cancer and end up the places we live, play, learn, and work” (emphasis added).

In response to this measured comment, Ross fired back with “No reputable scientist or physician, nor any authoritative textbook on cancer or its causation, considers environmental exposure to ‘toxic chemicals’ a credible factor.”

This is a truly bizarre utterance.  The SMALLEST credible estimate of the contribution of toxic chemicals in the general environment and workplace to the cancer burden, the widely-criticized 1980 apportionment by Richard Doll and Richard Peto, puts the share at roughly 5-8 percent (that is, roughly 100,000 cases per year or roughly 35,000 deaths per year, given current enumeration of the U.S. incidence and mortality statistics).  The President’s Cancer Panel (members appointed by GW Bush) recently opined that “the true burden of environmentally induced cancer has been grossly underestimated.”  The more recent IOM report in no way reaches a contrary conclusion: indeed, this panel concluded that “for some of the chemicals reviewed by the committee, it may be prudent to avoid or minimize exposure because the available evidence suggests biological plausibility for exposure to be associated with an increased risk of breast cancer.”  Sounds like a way to BEGIN to reduce the death toll, if you want to take your head out of the sand.

If we want to better pin down the true fraction of cancer (or breast cancer) attributable to environmental exposures, I want to make one additional observation reasonable people should not presume to dispute: epidemiology is running out of utility.  The IOM committee tends to fetishize epidemiology, but of course for a common tumor type like breast cancer, the signal of even an intolerable excess risk on the order of 1 chance per 100 will be lost in the noise of case-control or cohort data (and further lost in the “manufactured doubt” of advocates like Ross who insist on odds ratios of 2.0 and above to suit their purposes).  Thanks to the terrific archives that this listserv maintains, I found a 2006 post of mine that made this point: “Looking for environmental stressors only using epidemiology is like looking for distant galaxies using only binoculars.”

Finally, Ross’ grab-bag of misstatements contains this howler: “And lest we forget, they [NRDC] promulgated one of the most infamous hoaxes of all time, the Alar scare.”  How soon they forget that in the 1990 Uniroyal bioassay of UDMH (the hydrolysis product of daminozide (Alar), formed preferentially in the preparation of apple juice), which was published after the substance was withdrawn from the market, more rare malignancies were found, at lower doses, than had been found in the “discredited” 1973 study on which NRDC’s prior report was based.

I have a short article dissecting some of the many false claims about Alar (Book Review, 9 J. INDUS. ECOLOGY 243 (2005) (reviewing CASS SUNSTEIN, RISK AND REASON)) at the following URL, second item from the top: https://www.law.upenn.edu/cf/faculty/afinkel/
 
On this webpage ("Rodent Tests Continue to Save Human Lives," Washington Times, December 12, 1994, pp. 20-22.) one can also find a pair of 1994 articles about rodent toxicology written by the founder of group she called “the great defender of the petrochemical companies” (Ross’ boss) and by me.