Researchers have uncovered copies of sensitive internal documents destroyed by a Canadian tobacco company that could boost efforts by provincial governments suing the industry over health costs linked to smoking.
The documents destroyed by Imperial Tobacco Canada reveal the firm had scientific data decades ago showing that cigarettes were addictive and caused cancer.
"This evidence suggests that the industry wasn't sharing absolutely critical findings about addiction and the health hazards," said David Hammond, a professor in the University of Waterloo's department of health studies. "There's real potential that if they had done so, we would have had laws that saved lives implemented much sooner."
Prof. Hammond is the lead author of a review of 60 documents that was published yesterday by the Canadian Medical Association Journal. British American Tobacco, the principal shareholder of Imperial Tobacco Canada, ordered Imperial to destroy its copies of the documents in 1992. But other copies had remained in the company's UK headquarters and were included in millions of pages of information released by the tobacco industry as part of court settlements since 1998. That's where Prof. Hammond and his co-authors discovered them.
The records will likely come into play in lawsuits by three Canadian provinces against tobacco companies over the health costs of smokers' illnesses, Prof. Hammond said. In addition, most of the other provinces have passed legislation enabling them to make similar claims.
Most of the records are reports of original scientific studies conducted between 1967 and 1984 by British American Tobacco. Some studies examined the effects of second-hand smoke on rats and found it was dangerous. Other research cast doubt on the comparative benefits of low-tar cigarettes, finding that smokers compensated by inhaling more intensely.
"The studies are notable both for the wide range of research designs used to examine the health effects of smoking and for the consistency of the findings," the CMAJ review says.
A spokesman for Imperial Tobacco Canada, the country's biggest tobacco company, did not return calls yesterday.
The tobacco industry did not make the findings public, instead denying for decades the effects of smoking. As the review notes, Jean-Louis Mercier, the chairman of Imperial Tobacco Canada, testified at a House of Commons legislative committee in 1987: "It is not the position of the industry that tobacco causes any disease. ... The role, if any, that tobacco or smoking plays in the initiation and the development of these diseases is still very uncertain."
It has long been known that tobacco companies in the United States shredded similar documents to limit their legal liability. In a historic 1998 settlement, cigarette manufacturers agreed to pay state governments $246-billion (U.S.) over 25 years to help cover the costs of treating people with smoking-related illnesses. They also released more than 40 million pages of internal documents.Report Typo/Error