A high profile US legal case is to cast doubt on industry evidence claiming that vinyl chloride exposure is not linked to brain cancer.
Joanne Branham says she believes environmental exposure to the chemical is the cause of the brain cancer that took the life of her husband, Franklin, six years ago. She blames the vinyl chloride that they were exposed to for nearly four decades while living in the village of McCullom Lake, Illinois, a mile downwind from a chemical plant operated by Philadelphia-based Rohm and Haas.
The Center for Public Integrity (CPI) reports his cancer was one of an unexpectedly large number in the vicinity of the plant, with 31 cases scheduled to go before the courts. Commenting as the Branham legal case started this week in Philadelphia Common Pleas Court, a Rohm and Haas spokesperson said the company “believes that these claims are factually and scientifically unfounded, and for this reason, will continue to vigorously defend these cases.”
Kevin Van Wart, Rohm and Haas’s lawyer, told jurors in his 20 September opening statement: “The science will show chemicals from the Ringwood plant did not cause Mr Branham’s cancer.” He added: “Unfortunately, Mr Branham is one of many people who die each year of cancer, for reasons we just don’t know. That is a reality of modern-day living.”
There is a legal precedent, however, and serious doubts have been raised about the science on which the chemical company lawyers are basing their claims.
In what is believed to be the only successful lawsuit in the United States alleging that vinyl chloride exposure caused brain cancer, a jury in 2006 awarded $1.2 million (£770,000) to the widow of 57-year-old Donald Lattin, who had worked at a Shell Chemical plant near Trenton, New Jersey; the case was subsequently settled for an undisclosed sum. Mr Lattin succumbed in 2003 to a type of brain cancer called glioblastoma multiforme. It’s the same type that has afflicted 10 of the McCullom Lake plaintiffs.
Aaron Freiwald, a lawyer for the plaintiffs, believes he can prove that an industry-funded study on which the company is expected to rely is flawed. His investigation indicates that the study of more than 10,000 workers at vinyl chloride plants, begun in 1973 and updated most recently by epidemiologist Kenneth Mundt in the 1990s, failed to include as many as two dozen fatal cases of brain cancer.
“Instead of the Mundt study being something that Rohm and Haas and other chemical companies can point to as casting doubt on the link between vinyl chloride and brain cancer, it would become very strong evidence of that link,” Freiwald told CPI’s Jim Morris.
Freiwald has spent almost five years building his case against Rohm and Haas, which since 2001 has been part of the Dow Chemical Company. After reviewing old chemical industry documents, court filings, and newspaper clippings and interviewing survivors of dead workers, Freiwald concluded Mundt’s update of the vinyl chloride workers study was based on incomplete data. Mundt reported 36 brain cancer deaths; the actual number, in Freiwald’s view, is closer to 60.
“Mundt inherited a lot of problems from those earlier studies,” Freiwald told CPI. “The companies determined which workers were included and which weren’t. Older workers, in many instances, were not included. Those were the people with the highest exposures in most cases.” Both the original study and Mundt’s update were financed by the main chemical industry trade body, now known as the American Chemistry Council.
The undercounting, Freiwald said, was most pronounced at Union Carbide’s now-closed vinyl resin plant in Texas City, Texas. Union Carbide, like Rohm and Haas, is now part of the Dow group.
Mundt’s study makes note of only one fatal case of brain cancer at the plant. But a Union Carbide document shows 19 cases — 13 that apparently met Mundt’s criteria for inclusion in the study and six that didn’t.
In his research for his CPI investigation, Morris spoke to Vincent Cogliano, head of the International Agency for Research on Cancer (IARC) Monographs programme. IARC is the UN agency charged with assessing evidence of cancer risk and designating substances to cancer risk groups. Vinyl chloride is already included in the top group 1 ranking as a cause of certain liver, but not brain, cancers.
An IARC working group considered Mundt’s study and others when it reviewed the scientific literature on vinyl chloride in 2007. “There wasn’t enough evidence for them to say that brain cancer was significantly elevated” among vinyl chloride workers, Cogliano told Morris. “Only angiosarcoma and hepatocellular carcinoma [both forms of cancer of the liver] were considered causally related to vinyl chloride. They didn’t find good evidence for brain tumours.”
Should it turn out that two dozen brain cancer deaths were missed in the Mundt paper, “it would be compellingly significant,” said Cogliano.
The problem doesn’t end with Mundt’s paper. The bulk of the key evidence on vinyl chloride and brain cancer, some dating back to the 1970s, has come from studies of workplaces and has been financed by the industry itself – and when it didn’t like the findings, it set about suppressing the evidence.
A study of workers at 37 US chemical plants published in the American Journal of Industrial Medicine in 1993 showed an excess risk of brain cancer associated with vinyl chloride exposure. But the industry was not pleased with those results, and internal documents describe a partially successful effort to have the authors recant their findings.