McGill asbestos study flawed, epidemiologist says – by Gil Shochat and Joseph Loiero (CBC News – February 2, 2012)

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Government plans to approve asbestos sales to developing world

A major 40-year study on asbestos safety completed by a group of scientists at McGill University is flawed, lacks transparency and contains manipulated data says Dr. David Egilman, a professor at Brown University, health activist and longtime industry critic.

The study, which followed the health of 11,000 miners and mill workers in Quebec between 1966 and the late 1990s, is used by the Chrysotile Institute — a lobby arm funded by, overseen and closely associated with both Liberal and Conservative governments — to promote the use of asbestos overseas.

According to Egilman, as the dangers of asbestos became better known in the 1960s, the industry decided to do its own research and hired Dr. John Corbett McDonald at McGill University’s School of Occupational Health. Industry documents obtained by CBC News showed it wanted to conduct research similar to that in the tobacco industry, which stated that “Industry is always well advised to look after its own problems.”

“Doubt is their product. They just need to have a little doubt in the dialogue. OK? And doubt allows you to go in and say, OK, maybe they’re right, maybe we’re right, but nobody’s sure,” says Egilman, who has been investigating the dangers of asbestos for over two decades.

Starting in the mid-1960s, McDonald headed the McGill study. The CBC has documents that show payments from the Quebec Asbestos Mining Association to McDonald and other researchers at the McGill School of Occupational Health totalling almost a million dollars from 1966 to 1972.

Tremolite versus asbestos

Tremolite, an even more dangerous contaminant than chrysotile, is sometimes found alongside white asbestos or chrysotile.

The McGill researchers would suggest in a 1997 study that cases of mesothelioma — cancer of the lining of the lung — occurred in “most, if not all,” miners who had a greater exposure to tremolite and that the mines close to the centre of the town of Thetford, Que., were the ones most contaminated with tremolite.

McDonald suggested that chrysotile was “essentially innocuous” at certain levels and advocated for its export to the Third World.

Egilman, who has been a longtime critic of the study, argues that chrysotile causes mesothelioma and has called for the release of the McGill study data.

“The whole argument is based on contaminated and uncontaminated mines. And nobody knows which is which? That’s crazy,” says Egilman.

Egilman is not the only expert asking to see the McGill University study data.

John Dement, an asbestos specialist at Duke University and Dr. Richard Lemen, a former assistant surgeon general in the U.S., both told CBC News that they would also like to see the information.

Lemen said the researchers are “either hiding something or … afraid the results will be interpreted differently.”

A recent analysis sponsored by the Dutch government tried to assess the risk from asbestos for lung cancer. It looked only at “higher quality studies” and excluded the Quebec mine study “because a variety of limitations, notably insufficient job history information.”

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