The Center for Public Integrity’s Jim Morris reports this week on a civil lawsuit between the chemical manufacturer Rohm and Haas, and the family of Franklin Branham, 63, who died just a month after being diagnosed with a glioblastoma brain tumor. The Branham family is the first of 31 victims who lived in McCullom Lake, Illinois and are suing the Dow Chemical subsidiary for contaminating their air and water with vinyl chloride and other carcinogens. In “Brain cancer trial may influence science on toxic chemical,” Morris provides a preview of the duel likely to ensue between the plaintiff’s and company’s scientific experts.

There’s little question in the scientific community that vinyl chloride is a human carcinogen. That evidence emerged in the early 1970’s when workers at a BF Goodrich plant near Louisville developed a rare and deadly liver cancer. As Morris explains, the original cohort mortality study funded by the industry’s trade group confirmed the liver cancer, but also identified excess deaths from other cancers, including of the brain. Follow-up of the worker cohort continued, as did the evidence, published in the American Journal of Industrial Medicine, of an excess risk of brain cancer with vinyl chloride exposure. But the industry was not pleased with those results, and internal documents describe an effort to have the authors recant their findings.

Drs. Sass, Castleman and Wallinga recount the tale in a 2005 commentary published in Environmental Health Perspectives.

Two years later [1993], in a highly unusual reversal, two of the original four authors published a retraction saying “we conclude that our finding of an excess of brain cancer among U.S. vinyl chloride workers reported earlier was not likely related to the chemical.”

Sass, Castleman and Wallinga illuminate the turn of events using an excerpt from a 1998 Houston Chronicle article:

“Wong [the lead author] hadn’t received permission from the study’s sponsor, the Chemical Manufacturers Association (CMA), to publish his data — data that could be used against the industry in lawsuits, that might alarm workers and attract regulators. The unauthorized publication provoked members of the CMA’s Vinyl Chloride Panel and touched off a months-long effort to persuade Wong [the lead author] to recant, documents show. Although Wong denies that he was pressured, he changed his story on vinyl chloride, declaring that the apparent excess of brain cancer deaths among workers might well be the result of ‘diagnostic bias’ — better reporting and diagnosis of the disease in the industry than in the general population.”

That story’s byline: Jim Morris. The same reporter, now with the Center for Public Integrity, who is examining the possible implications of industry’s manipulation of the science for brain-cancer victims in their civil lawsuit. Morris’ original interest in the risks associated with vinyl chloride may have stemmed from a possible cancer cluster in the Houston Chronicle‘s backyard, Texas City. But because of his experience investigating other worker health and safety issues, I suspect he knew that the differences of opinion about the vinyl chloride and brain cancer link would not be confined to the pages of peer-reviewed journals. Beginning next week, we’ll see on display in a courtroom debates about the conduct of the industry’s studies, the differences between the reported and unreported findings, and the precarious nature of epidemiological evidence in trying to prove causation.