Yesterday, I wrote a post in praise of a collaboration between PBS News Hour and the Center for Public Integrity which took a twenty-years-after look at story of Erin Brockovich. As you may recall, Brockovich was the crusading law clerk (made famous in a movie starring Julia Roberts) whose work led to multimillion settlement from the California utility company, PG&E, to a residents of a small town in California.
That settlement was based on years of chemical dumping that led to hexavalent chromium contamination of the ground water in that area - and years of a company coverup. As these latest stories pointed out, the ground water is still contaminated (although PG&E is working on a clean up plan) and the town of Hinkley is now pretty a ghost town. The part of the reporting that I found most fascinating was the evidence of the way the company manipulated the state regulatory system following the crisis. As I noted, this is important background for anyone trying to follow agencies charged with protecting the public.
But there's another aspect to this story - highlighted in a very smart piece in Slate today by veteran science writer George Johnson - which looks more specifically at the health claims related to cases such as the contamination of Hinkley. Titled "Cancer Cluster or Chance" the article scrutinizes the sometimes hyperbolic claims of cancer clusters related to industrial pollution and concludes that they are based, at best, on shaky evidence. Johnson points out that the cancer rate in Hinkley was actually somewhat lower than of the general population.
And he goes onto make the same point about another well-publicized industrial chemical case in Toms River, New Jersey, which is the subject of environmental journalist Dan Fagin's newly released book (titled Toms River). "After five years and an investigation that cost more than $10 million, it is not certain that anyone in Toms River got cancer from toxic waste discharged by local companies into the atmosphere," Johnson writes.
Johnson, a long-time New York Times staff writer and a blogger at Discover, also has book coming out in August, called The Cancer Chronicles, which we can expect to explore these issues in greater detail. But for now I'd like to acknowledge his point that this is an uncertain science. To acknowledge that not all industrial exposures are hazardous exposures. And to also suggest that our obsession with the carcinogen question sometimes causes us to overlook the other, equally interesting (or troubling) aspects of exposure. For instance, lead, for instance, while suspect in some cancers, is more often problemmatic as a neurotoxic agent.
It's not a bad guiding prinicple, as we sort through the risks and non-risks of environmental exposures, to remember that these are never one-note stories.
--- Deborah Blum