Document vBnoxYKojwO8Q1KgOL15jo6n9

x C' V I M'T.Rsn Y OF OXFORD D\ .f t mrui of flu- Kr^iiM Pr lessor nl Me Jicinc DLI'AKTMKNT UK IIKAI.TII & SOCIAL SKCURITY Cmiu Epidemiology ud GmncJ TruJi (Jail IKcbU- K..J.I Oiiocd Ttl: Oifotd (OMS) 53762 Dr. Paul Kotin Vice President H p a 1 t ^ ^ a f r> * y jpii rnulrs"",""t John-Manvi1le Lorporation Greenwood Plaza Denver, Colorado 80217 13 October 19/5 PLAINTIFF'S EXHIBIT JM-2142 Dear Dr. Kotin, Richard Doll has passed me your enquiry on our follow-up of asbestos workers. To deal with your questions In turn: 1) Lung cancer in the absence of asbestosls Definition Lung cancer deaths With Without Expected Asbestosls Asbestosls Cohort: 1 Men, 20+years before 1933 10+before 1933 2 Men, 20-ryears before 1933 <10 before 1933 3 Men, 20+years, none before 19J3 4 Men, 10-19 years, none before 1933 5 Women, 10+years, none before 1933 Total: 29 31 24.0 None of the excesses of lung cancer without aentlon of asbestosls art. .td tiiiuj I' ? >igniftcant, but tnere is a suggestion of an excess, particularly in more recent employees (cohorts 4 and S), so It Is possible either that doctors and pathologists are not aware of the continuing risk or that this Is a genuine finding. It would thus not be safe to assume that the effect Is adequately monitored by merely looking for asbestosls on death certificates. Incidentally neither of the two men who died of lung cancer over 20 years after first exposure, having entered the factory since 1951, had asbestosls certified. (Observed/expected 2/<X52). 2- - ) L i q d_r o t t e_s mo k i n g ihr only records we examined were those of the six lung cancer deaths in men who entered the factory since 1951; all six were smokers. This information could be obtained from Turner Bros. if you want to pursue it. I I \ 3 1 latPnf nprinrl We did not examine mesotheliomas separately. The latent periods of the 3 coded cases in our study were 30, 45 and 45 years, but there are some further cases known to the Medical Officer in fhe f.irfnrw which w"rr> ir ploura 1 cancer. We shall be looking at this soon, it you are interested In pursuing it. As for lung cancer, it. is impossible to give an accurate figure for the minimum latent period, as some cases are obviously incidental. The excess risk is not statistically significant before 20 years, but there may be a slight excess after 15 years: Lung cancer deaths in men and women starting work since 1933 Years si nee entering factory Observed Expected 15 15-20 4 3.2 7 4.4 Over 20 24 11.7 Total 35 19.3 In this connection, two of the 6 lung cancer deaths in men who started work since 1951 were certified with asbestosis; these deaths occurred 17 and 19 years after first exposure. We have not yet examined the cases of lung cancer with asbestosis in those who entered before 1951. 4) uust levels uust levels between 1952 and 1966 were published In the previous report. (Knox et al 1968, Brit. J. Industr. Med., 25, 293-303). 197' levels appear to be substantially lower than the 1966 figures, but it is not clear how reliable this Information is. We propose to attempt to relate mortality to dust levels In subsequent analyses, but as there were no systematic measurements before 1952 this can only be done for those entering since 1951, and the numbers will noj be large enough for this purpose for at least 3 or 4 years."TThe difficulties are obvious - measurement techniques nave * hjvt'f the years, anJ men move between areas with very different levels in the course of their employment. Incidentally, it seems likely that dust levels did not change dramatically between 1933 and 1966, which is consistent with the finding that -3- tho excess of lung cancer over 1*5 years after first exposure t no s e starting work since 1951 may be as hiqh as in those starting between 1933 and 1950 (observed/expected: 5/1.9 and 26/14.2 respectively), but we need much larger numbers to answer this at all reliably. in i nope this answers your questions. Yours sincerely, Julia Statistician cb P.S. I realise on re-reading this that I have not made It clear that we have recorded asbestosls only when It was mentioned on the death certificate. No medical Information from Turner Bros., was used. I enclose our report* and the 1968 dust table. J f