Document 4vZEVKEDEx5RMk67O5K1JXRO1

FILE NAME: Quebec Asbestos Mining Association (QAMA) DATE: 1958 Aug 12 DOC#: QAMA139 DOCUMENT DESCRIPTION: Copy of Letter from Dr. Knox Commenting on Braun & Truan Journal Article - Epidemiology of Lung Cancer in Asbestos Miners ET NAH/JV/bOT/JFK Copy of letter Mr. Waddell Bpldemlology of Lung Canoer In Asbestos Miners. (Braun A Truman ) Arch, of occupation Health___ In a cohort of approximately 6000 "miners* exposed for 5 years at least to three degrees of dustiness - not specified - 9 proved cases and possibly 12 lunger canoers occurred in the 6 years 1950* 55 This gives a rate of 25.3 per 100,000 for proved cases and 53.8 for total oases (not proved). This compared well with 22,5 per 100,000 for the rest of the Province and 20,8 per 100,000 throughout the Dominion of Canada. Montreal was 32,3 and other rates were.37,2 for the adult stale population of United States, Since 1940 there were 19 proved cases among miners. There are a total of 33 cares known of whom 4 are still living and 10 are unproved oases. The paper makes no allowance for any alteration in working conditions at any time and does not give the total death rate in comparison with other areas - only the total number of deaths - 187. It doss not give the number of people compensated for asbestosia or the totel number of asbestotlc deaths and the number of lung cenoers in relation to this. An attempt is made to melode smoking habits in th calculations. Xo oases of lung cancer were found among the non smokers who were defined as not smoking an average of more than 5 cigarettes dally. The use of cigars end pipe tobacco was not regarded as smoking. Since 1940 we have total of 22 proved eases, in relation to a population of 1500 approximately. continued '53C*'- 022T If we give oureelvee e cohort of 1500 which le a crude figure and the number of 5 year workera will be leas. There were 7 proved oaaea In the 6 pars 1950-55 Thla would make our number for 6000 workera aa 2. Thla would be roughly 2 times the Canadian Mlnera rate or 2 5 per 100,000 proved caeca and 2 for total oaaea. Aabeatoala In thla paper la regarded aa the aame disease In all parts of the world. It may bo a milder dlaeaae In miners - and I think there la some evidence of thla but statistics with regard to asbestos miners do not apply to textile asbestos workers here. Here asbestos workers are "urban" and situated In the greaFtV ',v cV oV mMmMunUiatv iWews "4th their high bronchitic rate. In Canada minniers are rura workers for the moat part and should share sloloma of the ad intagea of rural life - including, as here, a lo>ww lung canoer `Ste. (c