Mesothelioma and the Chrysotile Defense
Tuesday, April 20th, 2010
Just a few days ago a Dallas jury awarded damages to a retired construction worker with mesothelioma, a fatal form of lung cancer caused by asbestos exposure. The plaintiff had worked for many years on skyscrapers and other construction projects, and when he was diagnosed with the deadly disease he sued manufacturers of construction materials who had used asbestos in their products.
The interesting part of this story, to me, is that the defendants used what’s come to be called the “chrysotile defense.” That is, they claimed the defendant couldn’t have developed cancer from their products, because their products contained only chrysotile asbestos, and chrysotile asbestos (they claimed) doesn’t cause mesothelioma.
Obviously this argument didn’t persuade the jury. But this claim about chrysotile asbestos comes up frequently, so let’s take a look at it.
Asbestos is a mineral that breaks up into thin crystals or fibers, and it comes in different forms with different names. One feature that distinguishes one type of asbestos from another is the shape of the fibers. Sometimes they are straight and sharp, like needles, and sometimes they curl. The fibers of “chrysotile” asbestos are curly. Types of asbestos with straight fibers are called “amphibole.”
It is not dangerous to touch asbestos, but breathing the fibers into the lungs can result in mesothelioma and other serious diseases. Proponents of the “chrysotile defense,” also called the “amphibole hypothesis,” however, claim that only asbestos with straight, needle-like fibers can cause mesothelioma. Curly-fiber asbestos like chrysotile is safe, they say, because (presumably) the curly fibers don’t settle in the lungs.
If true, this would be significant, because about 95 percent of asbestos used in manufacturing in modern times has been chrysotile. However, if true, mesothelioma ought to be a lot rarer than it is. And it may not surprise you that all of the “research” supporting the chrysotile defense was funded by the asbestos industry.
Physicians and researchers suspected that asbestos exposure caused mesothelioma as long ago as the 1930s. But in the 1963, suspicion became certainty when a physician named Dr. Irving Selikoff published case studies of asbestos cancer victims. The asbestos industry responded with an outrageous smear campaign to discredit Dr. Selikoff and his research. And for years, asbestos manufacturers adamantly denied the connection between asbestos and mesothelioma.
But science showed beyond a doubt that asbestos exposure really does cause mesothelioma. So asbestos manufacturers shifted gears and began to claim that, OK, maybe amphibole asbestos causes mesothelioma, but not chrysotile asbestos. And that’s been their story ever since.
In 1972, six major asbestos manufacturers formed the Asbestos Information Association to counter the growing scientific evidence against asbestos. The AIA was managed by a public relations executive whose firm also worked on behalf of Big Tobacco, which was busily denying the connection between smoking and lung cancer at the time. The AIA tirelessly lobbied the federal government to slow the implementation of asbestos bans and safety regulations.
Also, the AIA paid scientists to find possible weak points in asbestos/mesothelioma research in order to discredit the research. They couldn’t prove that asbestos is “safe,” but they could persuade some lawmakers and jurors who are not scientists themselves that the evidence against asbestos isn’t as conclusive as those other scientists (the ones not being paid by the asbestos industry) say it is.
The chrysotile defense came out of this campaign. The Environmental Protection Agency finally bowed to the overwhelming scientific evidence and declared all forms of asbestos to be dangerous carcinogens. But as recently as 2008 industry-paid scientists were presenting the “amphibole hypothesis” to the EPA, arguing that chrysotile should be removed from the carcinogen list.
And the reason the industry wants this is obvious — it would be a lot easier to defend lawsuits if lawyers could say the government changed its mind about chrysotile.
But the EPA has not changed its mind, nor has the World Health Organization (WHO) and a lot of other respected institutions. I guess that hasn’t stopped the industry from trying to use the chrysotile defense, however.
