Exploratory Sampling of Asbestos in Residences Near Thetford Mines: The Public Health Threat in Quebec

Abstract

In 2003-2004, the Asbestos Victims Association of Quebec undertook an exploratory sampling of the air and soil in the residential community of asbestos mining towns. In the 26 houses in the Thetford Mines area, 28 air samples were collected; one outdoor air sample was collected; 14 soil samples were taken; one dust sample was taken from a windowsill. The AHERA criterion was exceeded in 15 of the 28 air samples collected and the World Trade Center criterion was exceeded in five of 26 cases. The risk of developing asbestos-related cancer following such in-home exposures over 30 years is estimated at 1 in 10,000. Soil from the driveways or backyards of nine homes was covered with residue from a tailing pile. Of 14 samples, seven had chrysotile content in excess of 10%; in three, content exceeded 60%, and one reached 100%. Dust from the windowsill had a chrysotile content of 1.2 million structures of all lengths/sq cm. These results suggest a real public health threat in the Quebec mining areas.