Document 2qnoz68wE6JoMrGGNJj6NoY0R

This evidence is based on a number of epidemiological-studies-----three of the most prominent-being one by Dr. J. Corbett McDonald of 10,421 past and present asbestos mining and milling workers in Quebec, a second by Dr. M. L. Newhouse of 4,500 men who were employed in a British asbestos factory between 1933 and 1964 and the Third a study by Drs. Knox, Doll and associates of 878 workers in an asbestos textile factory, also in Great Britain. Dr. McDonald, in his study, divided his subjects into eight categories, based on length of employment and severity of dust exposure. He noted that only in the highest time-exposure category, comprising five per 'cent of the total, was there any increase in deaths from respiratory and cardiac diseases, including lung cancer. Taken as a group, the Quebec asbestos' workers had a mortality rate from all causes lower than the. level expected in the general population. r Dr. Newhouse in her study in Great Britain found that workers who had low and moderate occupational exposure to asbestos dust showed a rate of deaths from diseases of the lung, including cancer of the lung and pleura, that were comparable with that of the general public. On the other hand, another study by Dr. Newhouse of mesothelioma (a relatively rare cancer of the lirtifig around the lungs) in the London area showed a small number of cases among people who lived in close proximity to an asbestos textile plant and also among people living in the household of an asbestos worker, who presumably brought home quantities of the material |in his- clothes from work. The intensity of exoosure exbefienced. by these-- -7- 8501 0555 HFM -001227