Document nK5ov2OkEbMgZLG4EJozG21z

^7 Copies: RGS/T4N/NAM/JW/2 spares SM 8 131 '\ Extract from letter to Mr. J. Waddell from Dr. J. F. Knox. dated 22nd October. 1957. r /' ' v Dear Mr. Waddell, Asbestosis and Lung Cancer /i Letter 9/23/57 fJrom Vm. E. Shoemaker / This letter makes observations under three headings and I will use the same in reply. (a) Evidence with regard to the frequency of lung cancer in a group of workers must be statistical as it concerns the incidence of a condition to which the whole community is liable. (b) Conclusive evidence on the production of lung cancer in laboratory animals from exposure to asbestos dust has not ! yet been obtained. In the case of some such studies which were initiated by the American industry support was with; drawn at the interim stage because of the way the results ; seemed to be going. In this and in other cases mice were 1 used and these have not proved susceptible to the production of asbestosis by inhalation. Asbestosis in its advanced stages has not been reproduced in the experimental animal. When human lung cancer appears in association with asbestosis it comes as a late complication in an established case. (c) I have seen the journal from which the abstract was obtained. The paper quoted was one of many delivered on the occasion of the 44th Annual Meeting of the American Asso ciation of Pathologists and Bacteriologists at Washington D.C. -2- $8# 8 4 * on April 11th, 12th and 13th, 1957* *4t The remarks about Dr. Hueper are unworthy. He was asked on this occasion, as an eminent authority and the author f of several books relating to occupational tumours to act as V* Chairman of a Symposium. Concerning the "atmosphere" beii "favourably charged" I do not see the relevance of this re mark. It is the audience who make the atmosphere and this was composed of the members of a scientific society who are established pathologists. The relevant section of the Public Health Monograph y. ,\ No.36. is of interest. It is quite sound in its insistence zi: v " that what we are talking about is increased incidence of lung cancer in caseB of asbestos is. In the Doll paper all the cases had asbestosis as well as lung cancer. The im u1 portance of this is that by diminishing asbestos is we diminish 3 lung cancer. There is evidence that we have already done this. *$ 4 1*