Peritoneal mesothelioma found in a mine worker exposed to “tremolite free” asbestos in a Canadian mine

The Canadian mining industry has used scientific arguments to create doubt about the toxicity of chrysotile fiber. The argument that chrysotile does not cause peritoneal mesothelioma and only causes chest mesotheliomas at high doses has been used to promote the use of this mineral in developing countries and to block compensation to victims. Industry funded researchers proposed that tremolite contamination of chrysotile--and not exposure to chrysotile per se—is the cause of asbestos-related mesotheliomas in miners and millers. For example, researchers funded by the Quebec Asbestos Mining Association maintained that all but one of the mesothelioma cases found in workers from mines in Thetford occurred in miners who worked in high tremolite mines in the asbestos mining region. The specific data on tremolite levels and the locations of the mines that would support these opinions have not been disclosed, and other experts have determined that chrysotile is a cause of mesothelioma. In 2005, scientists retained by a US asbestos product manufacturer took samples from two Carey mines in East Broughton, Canada and concluded that they were tremolite free. We recently became aware of the case of a lifelong Carey mine worker who died from peritoneal mesothelioma. A pathology panel at Sherbrooke Hospital determined he had died from a peritoneal mesothelioma, and physicians who served on the Committee of the Quebec Ministry of Work confirmed the diagnosis as work-related. This case provides evidence that exposure to chrysotile absent tremolite contamination can cause mesothelioma.