Document r2J6xDdJxR3gzLLypxw5RnDE

------------ *0 ^:-X c. . - r-.v V3 "H ` i ;-N ..- r'* -` j r.-' w . -- . Cc 24th November, 1966. Asbestos and Human Health (J.M. Draft 10.13.66):, Comments by Pr.J.P.Knox. It has been apparent for many years that there are differences in the medical concepts between Great Britain and the U.S.A. on the question of Asbestosis. Some of these differences spring from our different legislation as regards industrial diseases and from our different methods of assessing disability and awarding compensation. My comments on this draft will be given below under page and paragraph number. They are given from the point of view now current in Great Britain. Page.l Par.3. "No longer considered a common health hazard". It is to assess the present situation in the Asbestos Industry that much research work is now being undertaken. Par. 4 Par. 5 This statement is not true in an unqualified way for Great Britain. Asbestosis has been proved to occur in some instances after exposure to asbestos dust for a period of 6 months. In this situation the Asbestosis has appeared after many years. The words prolonged and excessive would require definition as regards time and dust concentration. Prevention is by avoidance of dust inhalation. There is at present no effective treatment of Asbestosis, only of complications. The statement in this paragraph would ~ , , .seem to be at variance with that on P.8.Par.2. lines 678 Par.6 Par. 2 In Great Britain evidence has been produced of the association of Asbestosis and Lung Cancer since 1947. The first published cases were by Lynch and Smith in the U.S.A. in 1935 (American J.Cancer, 24,56) / Line 9, Suggest after "people" - insert (lwho - surviveIf. Pars. 2,3,4, 5, Are of doubtful value. They could be used just as well against the main arguments as well as for. Par.6 ^his statement would hardly be supported by those who have weighed all the evidence impartially. C</v* Page 7 Par.l There is no doubt that Dr.Schepers is a powerful protagonist of whatever viewpoint he expounds, -nd: expresses himself pungently in public. \ MTC 017524 contd.. 0001 0990 2- - He does not, however, invariably carry his audience with him as so much of hi3 criticism is assertive. The paper reported under Discussion (P.589 Biological Effects of Asbestos, Annual of the New York Academy of Sciences.Yol. 132 Art.l) by Dr. T.F.Mancuso preceded the remarks extracted from Dr. Schepers contribution at the New York Meeting, and, bearing a contrary implication, were well reasoned and documented. Page 8 Par.2 Ihi3 is not generally true of Great Britain where certain exposed workers are regularly examined by Medical Panel doctors appointed for the purpose by Government Regulation. Page 9 Par.1 It would be more correct to say that Silicosis is liable to be complicated by Tuberculosis, whereas no increased susceptibility to Tuberculosis has been noted in Asbestosis. Eine 6. Asbestosis is not universally regarded as static. All British authorities would agree that many cases of Asbestosis seen here exhibit progression. Line 7. Most authorities would now agree that Asbestosis may supervene many years after exposure to asbestos dust has ceased. Page 10 Par.4 The question of the frequency of Lung Cancer in association with Asbestosis is not judged solely on a diagnosis arrived at on one occasion during life but mainly on death certificates following illness, usually prolonged, and on post-mortem examinations. Par.5 Asbestotic fibrosis is not limited to the area of the included asbestos particle. The question of progression or non progression of Asbestotic lesions has no bearing on the possible Lung Cancer relationship, or the etiology of Lung Cancer. Page 10 Par.6 The 1951 papers of Vorwald et al, are widely disputed now and the recorded extracts are extremely controversial. Even Vorwald does not now uphold the thesis outlined in these extracts. ag< |T.7 There is contrary evidence to the theory of Gross and Smith in the paper of J.Beattie and J.F.Knox (1961 Inhaled Particles of Vapours. C.N.Davies. Ed.Pengamon Press) and supported by Nagelsphmidt (New York Symposium 1965). The only known epidemiological studies on this subject are those of Enterline(P.I56.Biological Effects of Asbestos, New York 1964). On P.I64 Par.l. he states that "this hazard reflects itself in an increased incidence of Cancer and Asbestosis". But, by and large, the appropriate studies have not yet been made. The sentence "a positive tendency to develop Asbestosis" suggests knowledge that we do not possess. contd.. MTC 017525 0001 0991 -3- Page 17 Page 18 Page 19 Par.l Thi3 Quotation from Lanza (l952) does not strengthen the argument.Medical blindness has been abundantly evident over the ages. Par.3 Braun and Truan's paper has been widely critised most effectively by Mancuao (P.592 New York Symposium 1965) Par.l Trace Minerals are present in Asbestos bearing rock3 (all types), and their importance is not yet fully assessed. I think studies on these matters may yield important results. Pinal Par. Dr. K.W.Smith's observations are of the greatest importance. o General Comment : These issues treated here are confined to "conventional" Asbestosis and ^ung Cancer. No useful comment on ;, Mesothelioma can be made at this point of time. ^1 nA Page 20 Summary. I append my own opinions against the seven categories. * \t Agreed Disagree with preposition of non progression. 6?<\ Agree with first proposition; disagree with the second on the point that confusion with other dust diseases is frequent. K. Agreed. .5- (K Insufficient evidence at this time. published to decide this matter 6 Agreed. 7. Agreed. jwrW-V mesSBBMB C3 MTC 017526