Document QbddnZzx4kvX58opx28YnO65

i^i w* 5. tan appear to have originated In the Untied State*, and seven In Canada, Some., of the earlier report* apparently Included abeetoa miner*, but U can be aaeumed, alnce 82 of the 99 caaaa bad originated In England, and since no asbestos mining operations are carried on In that country, that most of the reportod case* have Involved workers In th* textile or fabricating Industries. Such factor* a* smoking habits, family history of cancer, length of time In the industry, and age of the Individual caso are also notably absent In the majority of these reports. With this understanding of the llmijitlons of the existing literature t with respect to opldomlologteal generalisation, it may be of value to consider la somewhat more detail some representative earlier publications, a few of which were referred to briefly above. One of the most detailed studies and ono which deserves the most ssrlouo consideration le that roportod by DoU^) In 1955, This study reviews causes of death amoag asbestos workers basod on Coroners' records. It also attempts to estimate tbo risk by studying records of men who worked for at least 20 years In exposod situations, DoU concludod that lung cancer was a specific Industrial hasard of certain asbestos workers and that, after 20 years of exposure, the risk Is ten times as great as for the general popu lation. This arllclo Is important for several roasons, in addition to tho definite conclusions at which it arrlvoa. Tor example, It begins by stating that "in vlow of the Infrequency of aobeslosls, this large numbor of cases 0254