Cancer and Our Environment: Essential Reading

In the latest issue (well, the latest issue to arrive by post) of the Times Literary Supplement (Feb. 1, 2008) there is a wonderful (one of my favorite adjectives, so no doubt I overuse it) review by Sandra Steingraber of two books concerning the question of the relationship between possible and probable environmental causes of cancer and the citizens who by dint of circumstance are now "environmental detectives in their own communities: "Dead and Dyeing" (no, that's not a typo, you'll have to read the full piece to learn why).

The first book is by Devra Davis: The Secret History of the War on Cancer (New York: Basic Books, 2007). Davis earlier authored When Smoke Ran Like Water: Tales of Environmental Deception and the Battle Against Pollution (2004) and has been called "one of the world's leading epidemiologists and researchers on environmentally linked illness." Steingraber cites her impeccable credentials: directs the Center for Environmental Oncology at the University of Pittsburgh Cancer Institute, is a former adviser to the World Health Organization, served as a public-health scientist in both the Carter and Clinton Administrations, and is the founding director of the Board on Environmental Studies and Toxicology in the National Academy of Sciences.

The "basic thesis of this book," writes Steingraber, "is that 1.5 million lives have been lost, because Americans failed to act on existing knowledge about the environmental causes of cancer." Here are some of the factors as described in the review that "both acting together and independently of each other," led to this failure: a) "the cowardice of research scientists, who publish thoroughly referenced reports but pull their punches at the end, by claiming that more research needs to be done before action can be taken. Statements like these are then exploited by those who profit from the status quo;" b) "regulatory agencies have become unresponsive to new scientific evidence;" c) and perhaps one reason for the previous factor, namely, the well-known phenomenon of regulatory capture: "government agencies and charities whose mission it is to eradicate cancer...have had meaningful work on cancer prevention compromised by corporate interests;" d) for epidemiologists requiring access to industry (owing to the necessary focus on workers 'who are exposed to the highest amounts of suspected carcinogens') "the price for access, too often, is the promise of secrecy." "Having struck a Faustian bargain, occupational epidemiologists can have--and have had--their funds withdrawn if they go public with their results;" e) "various kinds of scientific evidence--such as animal research--have been gradually declared inadmissible in legal cases," the legal bar having been set rather high: "'Basically,' says Davis, 'before you can collect damages, you must get cancer or some other awful disease, show that someone else already got it from the same things you did, prove that you had specific exposure to a particular agent, find the firm that caused your harm and can now pay for it, and prove that they knew the exposure was harmful'" (I suspect the last is often an insuperable obstacle); and f) "outright harassment of researchers, including Davis herself...."

Our second title is Phil Brown's Toxic Exposures: Contested Illnesses and the Environmental Health Movement (New York: Columbia University Press, 2007). From the review:

"Brown, a medical sociologist at Brown University, has been a researcher in the field of environmental health for several decades, beginning with his groundbreaking work on the Woburn cancer cluster, made famous in the Hollywood movie A Civil Action. [....] As he demonstrates, almost all cases of cancer clusters, from Love Canal onwards, have been discovered by citizen activists--not by scientists, nor by government agencies [think Erin Brockovich]. This is because no governmental agency or scientific body engages in routine surveillance that would uncover sentinel health events [of course the government is adept at routine surveillance of another sort!]. It is also because cancer registries, which could function as early-warning systems, publish their results in obscure almanacs and do not actively investigate communities where cancer rates are elevated. Often, as Brown notes, these communities are never even informed that their cancer rates are statistically excessive. But, in the cases where citizens have engaged in their own lay epidemiology and have become environmental detectives in their own communities, new avenues of scientific research have been made possible, which, in turn, have spurred on better environmental decisions. When sympathetic scientists work hand in hand with these activists, new forms of knowledge are created that challenge the lifestyle and hereditary foci of conventional epidemiology."

As Daniel would say: Recommended

Patrick S. O'Donnell

Comments

[Daniel Goldberg]

It's more like "as Larry Solum would say . . . . "

In all seriousness, this is a provocative post -- in the good sense. Issues of occupational and environmental health, which are often though not always intertwined are likely a key determinant of population health, though I believe there is evidence that a relatively marginal proportion of people are proven to be exposed to known toxic chemicals.

Of course, the devil is in the details in this reporting, and there is no question that the biopsychosocial model of disease incorporates environmental concerns.

My colleague Winnie Hamilton, who does fabulous work at the CDRC (where I work), is PI on a landmark study of lead levels in Galveston. These levels absolutely qualify as a prime determinant on health, one that, through both prenatal and early developmental pathways, seem to initiate a cascade of phenomena that often results in inferior health outcomes.

On the other hand, one needs to beware of the awesome pattern recognition capacities of the human mind, which are so good as to find causal patterns where none exist.

For example, given the nonlinear dynamical pathways through which diseases cluster, given enough iterations one will predict certain pockets and clusters of, say, cancer. Some times, these clusters seem like too coincidental for comfort given the overall incidence in the population at large. In turn, sometimes these suspicions are well-founded, and other times they are not.

The difficulty of epidemiologic causality can give rise to a thorny epistemic problem: how can we tell the "random" occurrences from the "caused" occurrences?

In any case, fascinating stuff. As for references, as always, I'd strongly recommend Marmot & Wilkinson eds. (2006), and Markowitz & Rosner and Herbert Adams on the interrelation between environmental and occupational health.

[Patrick S. O'Donnell]

I think those who are concerned about "cancer clusters" are well aware of the complex epistemic and scientific issues that arise in such cases.

Re: "I believe there is evidence that a relatively marginal proportion of people are proven to be exposed to known toxic chemicals."

First, I wonder about the standard of "proof" here, and secondly, I suspect there's not a sufficient amount of evidence in this regard but I'm open to persuasion. Let's take just one toxic chemical, mercury, for example: "In America one-in-six children born every year have been exposed to mercury levels so high that they are potentially at risk for learning disabilities and motor skill impairment and short-term memory loss. That type of mercury exposure is caused by eating certain kinds of fish, which contain high levels of the toxin from both natural and man-made sources such as emissions from coal-fired power plants. One government analysis shows that 630,000 children each year are exposed to potentially unsafe mercury levels in the womb. If the government and its scientists know about the mercury problem, why do so many people continue to be poisoned?" See http://www.pbs.org/now/science/mercuryinfish.html

Then we might think about nuclear waste, dioxins, PCBs, asbestos....

Some interesting data about a host of other toxins found here (with links to govt. docs.): http://www.scorecard.org/env-releases/us-map.tcl

An important book by way of background information: Carl F. Cranor's Regulating Toxic Substances: A Philosophy of Science and the Law (New York: Oxford University Press, 1993). Two other works I would recommend here are Kristin Shrader-Frechette's Risk and Rationality: Philosophical Foundations for Populist Reforms (Berkeley, CA: University of California Press, 1991) and her Environmental Justice: Reclaiming Equality, Reclaiming Democracy (New York: Oxford University Press, 2002).

[Patrick S. O'Donnell]

And stories like this, "Study finds human medicines altering marine biology," might prompt one to think twice about eating fish:

"Sewage-treatment plants in Southern California are failing to remove hormones and hormone-altering chemicals from water that gets flushed into coastal ocean waters, according to the results of a study released Saturday.

The preliminary findings were part of the most ambitious study to date on the effect of emerging chemical contaminants in coastal oceans. It confirms the findings of smaller pilot studies from 2005 that discovered male fish in the ocean were developing female characteristics, and broadened the scope of the earlier studies by looking at an array of man-made contaminants in widespread tests of seawater, seafloor sediment and hundreds of fish caught off Los Angeles, Orange and San Diego counties.

The results, outlined by a Southern California toxicologist at a conference in Boston, reveal that a veritable drugstore of pharmaceuticals and beauty products, flame retardants and plastic additives are ending up in the ocean and appear to be working their way up the marine food chain."

See: http://www.latimes.com/news/local/la-me-pollute17feb17,1,6811201.story