Document YDJDKoOG7n49XZVnXyJoYYd1k

"dLciv tfc 1J / ri, jfojt X-gu&t-apologi-z to--you rl-ght at t-ho--outset of this -talk. i t VI Being--a foreigner- I have been -involved -in eemebhi-ng -e-aH-ed-FEEX - the Federal of Licencing -Examinations -Board qt- rtomot-,Tn4-KLg.-^mri T just finished tho exams last week. [Phis ic -the second time-I hav-o-taken it--whi c h i nd i cat e s to -you -how- -aueh-T -know about - basic soionGO-s--and bloohomi ntry and all--the., t.hirigs that haye-appeared on -fchis-.snene since I- graduated. The time I have had to prepare this talk has not been very great and I apologize to yon because what I am going to 4#- " Seed " a paper that was published this year in the British Journal of Industrial Medicine of which I was a co-author. I was only a co-author by virtue of the fact that I was abie to 4o in a factory in the United Kingdom which has preserved its personnel records ^<.- turn of the mwi the/last century onwamis and which has good medical records going late "ly\eje back to the/19^01 s-early 19501 sawel wMah had previously been studied by my predecessor, John Knox in association with Richard Doll who no ui Kefi jS c*r A is the Professor of Medicine at Oxford University whom I am sure A ^ Sir know of as a leading epidemiologist fiold. It was Richard you o" 7 Doll whosin 1955^based upon studies of the population I am about to describe to you^)]fc wae Riproved that there was indeed an association between lung cancer and exposure to asbestos. b< Tiii Pi 1111 , I think it ia-wiiways worthwhile to go thgeugh jj i v e tho old pat Veiling iiil Lilian! lillings^qsggsgfr^y what asbestos ft'0 maWricJ is well not easaotly but just..giving- you some idea of what vre are talking about. Ballko "tho"CfeairHian of Turnor d Newell} the rrmpTiny ^T ttK-i- nU i.n -- < ^1n jlUflflfi employeg in--tfte United Kingdom "and -many suboidiariee theghout the-wo^ld inialadiii.g mlue& 'l"lT'^"cHTatla, ________________ bacW'towvicl cleSz* w< ^ Hv?a t> and &wthont nhode-jia awd factories iw-ttahy-oountries the . c?h A00903 Lit fna o! UCC 010193 o4" 0,/' \kta^ah<X;i: Corr^a^j 2 Chairman who went out to Rhodesia to see for himself where the a asbestos came from and after breakfast said let's go and look at /" the plantation. i--we eordd juot have the- first olldo and th-e--lights %f then.1 fr-could iiluyiTatc 'Itj y^u juat--biaie-fj.y '^hat Asbestos is a iim \ fibrous mineral silicate and there are a number of var&A ies that are of commercial importance. I am not going to go into wUt the argument^ ipfl - about the differences in biological effects which exist between the various forms of asbestos. Chrysotile asbestos which comes from Canada, Southern Rhodesia, the Soviet Union, `SloOZi'ia*' A 6/i 'fo'C- j_2 Cyprus, South Africa:, United States,/the type of fiber which composes about 95% of the world's usage of this material. It is a hydrated 15 rr> . r* <- _ * ^ .i magnesium silicate. Crocidolite^which is a blue pallet fiber,aomoo i<\ Jgam South Africa at the present time from the Northwest Cape Province and *><> the Northeast amd. Transvaal. It 4;used to be mined in Australia but that mi-tiing no longer takes place and there was a H\. disastrous experience there with regard to aaeounts of mesothelioma a. , among the miners. Amosite is not an acceptable mineralogical terms `|i C\ abWv jtoo M A ,,' because it merely o4ettt4c for Asbestos manes of South Africa X4 , an A that is unique in that it only comes from one part of the world Z' /' A nni tbthe Northeast Transvaal. The amosite and crocidolite fock from the Northeast Transvaal oftenad occur#*in the same seam in the A goek and therefore it possible fee awy that amosite ie rnay be 6*3 vvce contaminated with aowc crocidolite* hat lo possible. There are deposits of amosite in India but I dorrt think they have been commercially exploited yet, feut-tteero ane seme there, of that typo ef gibor. bfcWtj h> ^rfteo'4e the eumminfeM^a'te- ggunatio (>9 series and just to ic digress for a moment the importance of the CG series (or the fact \ ^2 that amosite is part of that series^became apparent vhen^ Reserve Joining (iompanj^SP found^ itself enbarttleid with EPA, the State of UCC 010194 AGO 904 3 w.! f < Minnesota and various others people regarding the dumping of^ tailings^ -WcxvV ---------------------early > from its mines in Silver Bay^into Lake Superior^<wd/Srn--&olikaff A walt&e-d -into -Minnecota earel walfraod out again and really upse [/"`the whole-apricot thoare--and Hurt battle""!s sli-H going on-with. Reserve "T^-C fVtoei in 4 4\i A*- MtTTtTIg. I am sure you are familiar with that story, ghat- was CU H\<? letUf1 . is similar to commercially used amosite. Apart from the ftret A that, a lot of the fibers" initially ^i-soovorad were Daatimatrre /4nthophyllite * isn't very widely used in industry. It's one of k^OUL'P the oldest aiaed asbestos fibei* particularly^Finland where for thousands of years it's been incorporated in the building of Sjut-a. baths^ -f'you litee to go ii'iLu'llial soil ouiapatioa. However, _^ Mi ian1 b tenibly important. Biologically it is^very Tery^ interesting CiW( because no cases of mesothelioma have as yet been described Mth' tho Sloe 7 associationanthophyllite exposure, and-wo can forget about the t-" C< VVKi'cir iS remolite wtei-ah is often found in * A. commercial talc or industrial talc. th" fart tbir1- ^hryfr^ti'lT i to give-you oomo idoa f really nn an in Kn-K.T- -1- 1 1 -- , TV'rvgo V^n-hV, ~i T'^ia fViNC. aagnooium and various grthophyllito.an 3 a mine up.in Oanads^ shewing what hae happelned to the eowatry scowl's Mir. This is a composite slide aaid thio la what we did with asbestos "TFTe jS crus^ej Qftd faJ<?S in Rochdale in England, ghat la a rock, ht iiw epeitod at the mine ot 'xXO^ere# to some extent, ^t was further opened at the factory in the process ' is -FdOme^ in+Q nf iirhfiilr ***' called fiberizing. sa*d carding it wa#"^a<i aa a sliver and ft\e^ \stj ? >~i c* ^pun into a yarn,and that ia tho proooos and thonHthe yarn would bo- ,s Cai* woven or sold to customers. Cloth wulrl be used for various purposes OS enou/J (ftSulcihsA $ecsi**f !*'Aah'n^ (/v t*i ^ fl'th'oi-' *vte,tu-t'xw zQ y AantU&g. think I think you should appreciate !- -you1 -will-re ad in the papon -i-p y/Mi VioTro -i i- nr ^irh tn t~11 111111 I 111 the fact that in the United Kingdom, Regulations were made in 1931 which took affect UCC 010195 A0030b 4 6in prior to the making of those regulations^ which were called the Asbestos Industry Regulations^ and-wfrieh -therefore only fin t^-wahf.nf.nn irrHt^4=.yy..-anrl that aUn in i mp^r-fan-h. fr-nm the pninti.^f v4aw nf what happens subsequentLy hnweynr those rrgulntl-cns geGultad aftaa a study whiah was conducted by M^gywhothor and Price omJ \t became. in 1929 and published in 1930 which is eae-of-thc nest famous study the history of the jn..i~hic. fi<44 anfr 1u& a milestone in/Kaxfcaxn: British asbestos industry. What they found was that in people who had been employed for 20 or more years, - 81$ had puJ^onafibrosis. We are talking about r"Tn"Tnb~,r tihnt-mhnrtnnl r im tir a 20th Century disease. The first case of asbestosis was not described until the beginning of the Century in London by Koclaqug [Mu-Cfav - and -fchorofopc this io a 20th Cenlui'.y occupational disease. The first evidence that exposure to asbestos was going to cause a problem to the health of 'trite workers was the finding of asbestosis and the regulations that were made in 1931 and that took affect in 1933 were designed to reduce the incidence of pulmonary fibrosis. rW Lung cancer was not associated with asbestos exposure apart from A speculative case histories that first began appearing in 1935* No epidemiological study was done to confirm this suspected mryim a association until the work of Richard Doll in 1955* Although the same Mop.rywhother in 19^7 had shown that 13$ of asbestosis cases diagnosed in the United Kingdom wera_dying of lung cancer or had died of lung cancer. That leads to' another ~pr ml ~it1 nn. n>onAn ulii ifh ''s-/ -- fhe devfyjjnvU ef 1m don*4 intend tn -dwell 1 upon -and where asbestos is ^ a car\ prerequisite for the development of lung cancer or that lung cancer gccu< in an asbestos workers without asbestosisio neyoptholopo-nn --inn rmd irr irmil d rnly nntnr frii iimi'iy nrc"J""n4"1 especially in view of the known multiplicative effect which cigarette^ x& smoking has on lung cancer in asbestos wo^kj^^ q g UCC 010196 5 However^--I--s&w that almply tu pulnL uul whaL llie -e it-uahi-on .was lr 1^2? ,, -Uq--iOjn uith T-P^aT-H--t-n-fl.chflofng-ig. Sides Pulmonary fibrosis wh of*.- - WofhsVl srippling a&d ka.ij.ling peoplo a*tfl 8l% of thoseAwith more than 20 , years exposure wmpo eaffaring fr off*"-tilai a condition. By comparison gji-i\if iV \Q7, in 1975 only0-77or0.8% of the group wa*c compared with 26.2% were A 3W? A v*". found to have asbestosis and the 20 year and over.fcfce incidence wre X.! * down to ,\fir!rr,h obviously is still xh unacceptable but what you Ike i<n iKu y .>* have-to remember i'g that- some of bhoae cases were 'in fact exposed Hr e 1^,3! eKtfise<> as beforeA regulations. They were still wsiritiag andA. this wax a is a table of prevalence not incidence they were there and counted. It does indicate quite dramatically that those regulations A had reduced the incidence of asbestosis. Wawgo te the / t- Vj'f'V.p fnorlaify his co-hort frhnt we are describing in the has been the subject of I 3 previous reports and the last of these i ispinxs was published in 1968,-tho oro prior to thxa and~They from dealt particulary with mortality al lung cancer and respiratory disease in workers exposed to the high dust levels which preceded the 1931 asbestos industry regulations. They at^empfted to examine the 17 ,, dependence of lung cancer incidence on Ihe pafe7 age and duration of exposure. A Thip t~i I mi _jn 1968 the cohort was divided into 6 groups. 0 /v A be<0< t<^3 buy ' ^roup 1 had more than 10 years of exposure xhblx groups 1, 2, 3 and b luxdt toV&l ps>syA ' all had more than 20 years but group 1 had gj.ua Lm--Ilian 10-ycar-s A ovpncnT-a 1033. Group 2 had between 5 and 10 years exposure 3 before 1933 when the regulations took affect. Group $ had less than 5 years exposure and Group 4 had had no exposure before 1933- Group 5 was all males and had had more than 10 years exposure but less than 20 with no exposure prior to 1933 and group 6 was all females and they lexx had all been exposed after 1933 for more than 10 years. C&ua LotUW (Jbie.iW WhTin ymi VMr n4-- cancer of the lung and pleura, sain 1rlift t tl*r* A- uoe^ observed wa^l^ and tho oxpoe-ted. 1.6^so there about > UCC 010197 jCrLeX*> 6 excess incidence of lung cancer in fcha-fe group which had the longest exposure prior to the improvements which came with regulations. At) you go down you see that that Mminiohos. When you got to 10 f ft tout 5P<\ '. i* -fa^ group hw*e no exposure before 1933 with than 20 years, the -- difference is not statistically signific sfyiffl flbstvvaliu* a.. That was^very interesting but the authors were wise anA point out that no &ax3xKx firm conclusions could be drawn because little carcinogenic effect wa would be expected for 20 years after first exposure and some of the follow-up had not been for long enough. `If wc juofc--go thT-rmgh...fajQ mnre dealing with that, rnhrvrt-,,ar with horo %w]in4)ftye the men and women all exposed fas since 1933 and you fa can -goo that cancer of the lung and pleura max there was no statistically significance difference and in the women there ^^PoT-on^a. b>e^ \hjjs " and-that was only 2 cases and it was not possible to state what the (fec&uu e| bvjiQJ , meaning of that was^ What we are dealing with here is men and women employed 10 years or longer since 1933 This is--bhc ^gurag group with less Ilian ?0 years or'46-to 3?9 ycais cUiiT-yP'tr see no difference j-w Lliu uUStJj.' veil lu Lhe 'TaAa'g^-i-fte-ardeTTWTrf luw-g-aetneer . In fAlStA 0+U4'(Ql i_'>c_(-u$t In men employed 20 years^those who worked before 1933 as we have muc+c 1urjau*cc*i Obsess e^sri'j. sai4--bofore 11 to 0.8^tll to 1) and.all neoplasms 15 to 3 swad DMi'gc ^V . ^^ 1933 3^to 2.; hu< therefore Jit appeard from this information AA ^ / that people who had worked since 1933 were oatr no longer at risk awj if you accepted this^ that^the dust levels tfeert had been brought down^had been achieved(fa~l^sappease of the lung~canceFl) Further more this was against a diminishing background of incidence of asbestosis and as in 1975 the prevalence of asbestosis was only f.0.8% in the factory population studied^ The report published in 1977 is concern^with the the post-1932 population mainly^which^ao I oaad although exposed dust levels UCC 010198 A00908 7 higher than the present imK5Lfci permitted levels, tMtf rtirr'1'1 "'i"i"" was employed during the time of improving dust controls and plant modernization. The study is based on 1,106 men and women s\ kcwe enlyf 284 women/ and the cohorts Jute been roughly sub-divided in the same way except that you will see there are only 5 groups instead of &JLJiiai Lliu" prgWluus gi*gwp"3- -andhave baaii nmmlsiiiwd. It think'-tihat^-g wliat happened. I don't want to-go into it too, catiofuliy. A^ain we got years in asbestos areas 20 or more, 10 pr-^lnore before 1933N^iad than 20 or more less than 10 we hay^aken^out the less than 5 group frbsithat and then we have jpHk gone on so that will be from to 10 insbfe^d of just J^-to 10 and then we go on to 20 or more with no exposure afte^*^33 and that's the group we are particularly tuxiE intereste^Kln 10 to l^su^d then females with 10 or more. Well there^ay^be some tamlK females wnb-4iave done 20 years. We get }?Z*L06 with a total of 16,000 person year's-, of observations. Re-examination of our personnel records since the Ia last report in 1968 showed that a further 23 workers were eligible for inclusion k ciin cohorts 1 and 2 and in addition 205 workers who 3ww completed 10 years employment since June 16 1964 were added to cohorts/3 j *+ and 5* So the study comprised 822(nien^&nd 28k women and the followup was until the 31st of December .197k using the factory paxa personnel records and the National Health Service Central register. Only 2% of workers could not be traced and 13 nird thmV 1.2%) recordtiin the National Health Service Central registery as having imigrated or were not currently registered with GP. As you know everyone in the UK is registered with a rvPT yrm bnue tin hr j but mnnti prnpla nrr . S^imr l/M ynn nnn rnn that g vPTy arnaH Percentage trie fTOl. P^pfiini ally among the working populafeioir-wliu are iurtr abl-c nffnmri pani+ n fT-aflfmawt The remaining 1,071 ^96.8^have been UCC 010199 A00903 8 followed-up to the end of 197^- The number of deaths in each group which have been attributed to lung cancer^nd lung cancer includes deaths due to mesotheliom^sHit ttaBtyg The nwafrar of deaths in creh group attributed to Imp oanoor other cancers, respiratory disease and other causes are shown in the next slide and although it looks complicated it isn't really. If you simply loplr'at tterb column K s' ifhi 1" the mxx cause of death, which 'js lyrfig cancer and mesothelioma j other cancers respiratory diseases and^ther causes, and if you will ^ SKoiJ d '^ just look at the oneswhich statistically xxgxifxxaEtiyx significant K you will see that again h Group 1 (which wo know before p-e^ - -^ we-had the 10--observed to expected ratio/ana in gxmmp the respiratory diseases again there is a 3*6 observed to expected ratio and all causes the ratio is about 2 to 1 so there is an excess mortality in this population which is largely attributable to lung cancel1 but some of which is attributable to other respiratory diseases which might reflect a Mix residue of asbestosis in ihm this population. The expected numbers far thooo of you who are interested were calculated from National death rates by 5 yeSn periods and 5 ou/fk^ year age groups. To insure that the expected are not underestimated, imigrants and those lost to follow up were assumed to be alive on December 1, 197^- Deaths before the 1st of January 1931 or after the yacax age of 8^ are ignored and expected members are calculated accordingly. In Rochdale itself lung cancer mortality was lower than the national average among tho men which is interesting, n--that'This is the iaxi largest asbestos textile factory in the world. \w9h . Rochdale b&s a population of about 80,000 people ami iifc had a lower than average lung" cancer mortality. It doesn't prove anything but jwj. if km tmwr-feir the an" wliir'impMghfrt asbestos is an environmental pollutant which is going to cause an excess incidence of lung cancer in the general population ir^this doesn't seem to make sense. The A00 9 SC UCC 010200 9 -ftl-l rt-f: K- standardized mortality ratio ix in Rochdale is 87A and oimilar for women lOWliliub1 ^ (^959 to 1963 Regis te*4i ^general 1971 Workers 'e- ^ first exposed before 1933 cohorts 1 and 2, suffered from excess of lung cancer and respiratory disease, Rxxii AA J ^particularly those with 10 or more years exposure prior to 33, jthhere is also some excess mortality^lung cancer and mesothelioma ^36 observed and 19. ixpected^ttore P and respiratory disease(^35 observedy25yexpectedj P rvtwAff O.Ojj) in those who entered after the 1st of January 1933 s^cohorts 3>ss *+ and 5 combine^). ou combino thoaa "3 eehagfrs. This excess is very much less than in the first two cohorts. Wheife i'l lndl'cales is" IliaXn those pr~p1r ~i i tlr 1 Tnf~r "fTlimr up rtmr thnur pripi n -~hr were first exposed after 1933^the longer follow up indicates that there is still an excess mortality from lung cancer, mesothelioma and respiratory diseases. In the 1968 study there was a slight excess of circulatory disease in cohorts 3 and that hasn't increased (27 observed 20.6 were expected^ In cohorts 4 and 5 there was a matching deficit/50 observed,60.10 expected. The iftoidance that this was probably a chance observation seemed confirmed. There were 16 deaths attributable to gastro intestinal cancer comapred with 15*7 expected. This cohort^ever since it has been formed and iM hao followed, has not yielded an excess incidence of g deaths from gastj^opntestinal carcinoma. It is also interesting that in a paper published in the same issue of the British Journal of Industrial Medicine^Elmes in Belfast^following up his insulation workers finds the incidence of gastro-intestinal carcinoma is declining as the papal time goes by and thinks that this might be due to improvements in earlier years. Raw that feg-is fallowing Mil population farther xkB.ui.iii ulna! "iin-liiwj. However this excess incidence of gastro-intestinal carcinomaj In /asbestos workers appears to be something that is related to the .most heavily UCC 010201 ' LL 1 2 10 exposed gx groups* mod A this group of textile workers in the earlier years was probably as heavily exposed as any, it has progressively been getting less and less exposure and ktu s excess of gastro-intestinal carcinoma has k never been found in noch'daliL think xx will o***y find that gastro-intestinal carcinoma obV is associated with it in oomo very severe exposures. That is just my personal opinion. No excess^for SHa.y -ef thaso^jhat is statistical gastro-intestinal carcinoma approached/significanfce in any cohorts ai and no peritonewa mesothelioma was reported. To distinguish exposure immediately after 1933 from that under present conditions cohorts 3, 4 and 5 were divided into those first entering or first s. being exposed from 1933 to 1950 and those starting later. The reason we took 1950 was because we begardxd flgfe as the start of the modern period in that factory.becau&c Jt was the year in which >' I1''/ routine dust sampling was initiated. Although -Merrywhether had> way back in the 1930's herd tried to give some indication as to what he considered to be an unacceptable dusty the instrumentation and the techniques were not available to assess dustiness ifr-numorionll.y assess accurately. It was only in 1951 when the thermo^ p(ec<ot'r&\oi pcTcrpitn-tar came into use in that factory^ and rate then fiiihfrciqniiintr^y was followed by the long-running thermal pel>cipitator and then, in 1961^ by the membrane filter method^ that it was possible to attempt to measure wtet the exposure jp^sn-of these people and to control the measurable environment aooording to/dust levels rather than ao pending viable. best achievable resultstvioibly. Observed and expexted deaths for A ___ those first exposed between 1933 and 1950 are shown in Table ]RL4nrb mew X-- + V, -i nlr hafAT-p WP yp-H +-V,qt.o nr, -uro or> -HnoT*v ffion nUll If nTTliri l~l f1 T f t Bjrpncaa 1 933 t" 1950 iftgll' fiPUt) lUgpW^d &v iates'dime -ganaag -^-40 ua^.-obaare.d cxp<n- led"116 with a l LTT' 1 Tati'C. Here we find that the 1968 authors UCC 010202 XI wise to add a word of caution about the length of follow up. It had only been 20 years and 20 years may not be long enough because here Wr-e * and we i*ad- emerging xmt something they didn't find/that is a slight excess i^o by n-o meartc tho eigni-fioant- G3gu.it ju -of 11 to 1-that w ha via "hart prmn nnnty^ Vnvh fVimia . i a-p f j3 1 n n!4 gl.* of lung cancer in those persons exposed between 1933 and 1950. What about 1951? Well--we liauu lT"ay,aln. We a have a ratio of 1.9jbv*' ey.iV'-W lu-; CO^'eA J&itt.i \' That lo -o-by 6 cases observedto 3-2 S expected. The numbers owe. BMrgirt at this stage he. small and th,,efore this has to be followed ^ up a*wl \fcjb have to increase the numbers and ikst iBmgtfr g wo havo ta b\JuV I ft Wi 7 aH2j. ft* ` lengthen the follow-up % Bwb umni people who first entered since 1951 wfl it a lftp4 gives you ^2 4- years still show this slight excess. Again the statistical significance is not as great as for the thcr half of the cohorts not aaagg eicftefrly tho half other /3 rrpnTilT'B,t'n1lJr ,finn "h , but here we have evidence that the lung cancer has not been totally eliminated in this population. There have been very few deaths among those first exposed in 1951 or subsequently and if we look at table 4-, one of the things that is going to crop a up about those 6 cases after 1951 is whether they smoked or not. M ir ae iMgicmtant fofr the othoro brtt \jiJe don't have <*!! ftc the information available in medical records but we do h for a certain period of time when- smoking histories were added. In fact, the lack of inforafatitin on cigarette smoking in the earlier studies was a serious on{issipn, but there were no 1`Mwis kept in the medical records off a -Qigarotto oaeleiRg until I wank 1966 . T o-Hot.-ho^ r^-n ^ a making habr^s. Fauum tlrat'-Piiy Luuld see felwt S 1976 if you broke the population into age groups smokers, ex-smokers and non smokers i waftt go*1 into hew thoee-'ago defined jwb ouffiee to 913 tfea-fe--that '"g-fche way tfroy ware at ttoa tiiraa. "4here were 22$ who were h non-smokers, 13$ who had given up smoking and ihajc x there were UCC 010203 12 65% who still smoked. aAcFthtfse yere comparable to the national figures,in a-way. This population was no different fcx it in its A smoking habits from the general population- What do yoxr do about iy / smoking*?--- don't know. Table / shows deaths - lung cancer/including in th. en ani Q. ttr.t expose* 1933 to 1950 and men and women first exposed 1951 or later. They are distributed according to tho by day first and time since first exposure. me- yrvn innv in + ^ iL. yo^-no g-ir^q first 1 i]-in-iirr 1$ bo -ip) 0 years or mfljnti)_T^n the the 20 years or more 2x1 the ot :- ;i , ratios is 2 to 1. .tho&o-tswo groups it--probably io wet1 9arcant.. l Men and women first exposed 1951 or-lator 2Q_y.earo or mure 'if-you tnkff mryt'gYyanffY'fcakg that pmup If ln hiding? ^h?fn v?s jn't~ fl>jm]t IQ yp-flf.q which is clopp finn11^ "in "*lff " T* n?l HimunrT-ivP Oj* * g 3 nmi 2-you get 5 observed^l.8expected p.7 afr-yeug ratio of observed to expected^ The 6 employees who were first exposed after 1950 who died of lung cancer were all men and they were all smokers. 5 worked in areas where dust levels were high in 1951 and one of them may have been exposed to asbestos dust from 1925 to 1930 in a previous occupation. He was a welder in a shipyard. No case of mesothelioma has occurred in the population first exposed afte^ 1950-/ a but that may not be long enough for follow upj Although in view of J. the long latenl period, would yet be expected. An approximately (V multiplicative effect of asbestos exposure and cigarette smoking x incidence on lung cancer/has been suggested. As you know, Selikoff has suggested that an asbestos worker who smokes has a 92 times greater chance of dying from lung cancer than a non-smokfeng non-asbestos worker jvn+ ^ + ^ WI1iri an asbestos worker wi & an 8 times greater chance of dying from lung cancer than has a ej, fticT-ti* yrfrlnnr^hi^-Tlftflr nnt rmnlrr But without detailed smoking histories which have been collected for the future, we can't quantify what the !u}0 9 "i * effect of smoking were in this particular study. Asbestosis wan UCC 010204 13 oX \r> found by the Pneumoconiosis Medici^ Board arb- 03caminatiiant of t three of the six cases. They all came to post~morteyfm. All asbestos -}o rsV; ' - , workers in Rochdale x who die/' have their x deaths reported either by their doctors.to tho-ooronoor ar the hospital yope^t tm the } 8* for, y eePQBwg or by the xxxixx register of marriges and deaths. A This has been done since 1930. The post morteyfin rate when I once looked fvcM'y into it was me r cry 70% amawip whichN.js pretty high*-and f\ I used to go to every post morte/m that tool^r plac/. XHSjfXxxa: There is a lot of interesting work which wil^T~come out of the e post mortw-un work which was done in Rochdale. The numbers are too small for the magnitude of excess of lung cancer in those first employed after 1950 to be estimated with any precision. The implementation of the asbestos industry regulations started a drive to improve dust levels and as I explained to you the p-pwhlrgma: >f UT; . process were fiberizing the fiber came from the minesv xax was opened mixed and there" wore certain operations such as 1mixing opening bag*-slitting mechanical bagging. Thaw hfaey wont on fcfti^to^phe carding pa process awd if you are familiar with the textile industry the carding is simply a matter of teasing out the fibei^layering them all in one direction and yau do this by passing them through two rollers moving in opposite directions with ahnpjaed needle& projecting from tease_jjiem out. and yeu f\ is wki'cW get |4 fine web and then you, talia A qj*J Ca< twiifW; mill arid jmjlt spin it and- Jbhere Vcbm is dot? . are different grades of yarn .firm nr iirh?rovnr and then ynn hrnning /A x is a winding lij the and if- you--eve r --get w-i tb '''b^ ffTrTinc"H`"ni rr 1 Mn1 M'i'""Ti1i PI mrliv'r are the wheft gnecnfrom vrheft te white and tha wliaryg'PP'ji wimp and down and ycnv * . oanTt forget it that wajf and that'a ttcrw""j<utL weave. L?t: ' Pl-a thing is obviously used for packings. Yon do things with platting C&v In tVxpv-# '.a.aJyJ -gp. w dattte irnpiegw-atirTg^wd-th pxask grease or graphite and this 4soh stax# \J^m s*' - M- A . - H ) ^ TTr,TTTpt- Von non or>n yaaT, fl AA|)i ' " UCC 010205 m- I think t-hese--&& average--le-vels-and in those are particles per cc and ' f^hfir -for rn Shat operation, I'll show yon in a moment, is totally closed. f ^y , J- ^ ^ .r (jff course that is the way to deal with it~anything _1 f you close it you got _0 A^ no dust. Put thooo gradu-l-iy-wcnt down '6'fiber in A* to 3 in ?*!'. This factory population was used and studied by the British Occupational Hygiene k Society in 1966 jsh and on the morbidity study which was done at that time tint a -oth mortality but a mopM&ity-otudy [the /present standard for asbestos sisra fiber was developed.ad to her*op of the people who it A developed it became widely accepted throughout the world and/is how the as A y \(V , current standard ^or threshold limit valuefjin asbestos of x 2 fiber/cc. Originally it was a cumulative standard of 100 fiber^ pan years/cc,_if a man worked for 50 year in 2 fiber/cc he stood a 1% risk of k getting asbestosis. The standard was not designed for lung cancer. Although there tycV the i''D<9evii ,i /e;. u-n, *mL>s some indication llial I have shown you, if yau piaeluec asbestosis aloe 'yoduoo the incidence of lung cancer bw< yww may have to reduce the AA exposure levels further still below 2 fiber/cc if we are going to eliminate the lung cancer. However no population in the world has been followed for long enough which has been purely HoqmxiK exposed to 2 fiber/cc or less. No population has been followed to sa'j' that 2 fiber/cc is or is not a A no effect level for lung cancer.and ao you teeufThere is a lot of controversy about whether Jjhere is or isn't either a safe or no effect level for any carcinogen. As you can see, in certain operations dust QmJ levels came down dramatically by 1971* in the whole weaving operation 1kA _______ _ lere were less than 1. 71 11 1 >Viovi 1 *ViT> n 1 !rIn/1 tha- t weaving there has never been a case of lung cancer associated with Br r ) JT QjcM' exposure that n know-of and asbestosis doesn't occur in that weaving shed. .anH f.hflfr vby~fh" old timers^ people who were involved in reporting the data to the British Occupational Hygiene Society in 1966^and some of them \ USiVuj " had been at the factory for a long time^ -PaJ ng their gut feeling f^lt^ q q ^ 0 that 2 fibers/cc was a reasonablj>level because of the health experience UCC 010206 15 of that weaving shed. No single(population in the world has^followed-up x, Ul'k. /' . for long enough at a 2 fiber/cc or~-Kx less level to -**y^ based upon human experience who the r this is/an adequate level or not. -fect'o look T- i \ Wtfs' \ able>r whi-ch ii a the mean dusKtabl-e an/d the number of men exposed a** Tk to them. Frompftb to obviouoly -i toH you we dnlftH have dust counts . ^ fpoLiasiC. dU - S ^11*^6 ttii*y ili rlvLi11 vrmTTTff rwt start -hayingj^ust counts until 51 - tha-t.-d&. auiitx but It is Cased on calculations made by the committee of the British Occupational Hygiene Society (&er& the etatws 'Oo-a /\ -a tatiron involved wals Geoffrey Berry of the Medical Research Council's Pneumonociosis Wnit in Penarth)a4 they arrived at a menae of oalculating iWa/ levels whet would be a reasonable estimate of exposure in those years when dust counts were not available. So-youcan ooo ac tho yp31,g Ky Hl1|,t n -iy. h m PWM. --III HI IQp Ag***?- 1952 *yv`t a^" the beginning of a modernization of the factory whioh wac completed in fAovW t lot- worm was done ^a--lo4- o jobs were changed^a- lot ef .(( v^O^O'rtq procesa^were l^i&aaad and tfeect resulted in a better environment. 1969 /V A A new INegulations were made. Those x new regulations were called iliE no caf*J i' A . /I >' ii a /V tf longer x the (Asbestos Industry (Regulations but the Isb bestos regulations A and they applied not only to the asbestos industry, but to anybody using asbestos where ritsxi asbestos dust was giving off in LP~i/> concentrations as ijB liable to be harmful to the health of the exposed person. As opposed to the American method of doing it, the British isax have not put a figure in the asbestos stand?T3i^ri regulations there is no legally enforceable --TS--A figure. The way it has been done ispublishing as an addendum to the ^ Ubk"C standard > you like guidelines for the benefit of those people xteg -to whom fc> ^LkUy |tu WJtuijju;' Tu fyiM the otaftdard applies. \diioh indicate what the current thinking of the ^ duo* factory inspectorate is ,at tfae proeonfr-time with regard to the levels V be &0\\e+*4 . yjfvy they arc, going tQ 9nfoi*c. That means"^hat _tf they want to ohwtfcc ,,. level^ W gusstxgyg t^aeppew^and they have already changed them once since 9),1969V all they have to do is 7 I `Ikfi ~i +v.n+ pi-'^'fr^pQ','> ^-n-H ^-p t. tA.-,t0n 0a..3.m 1 7 -md publirjl y.iiuW'ier, It Ajseh doesn't require an act of Parliament or any UCC 010207 '. 16 fof.rv**/ fori^Wei.4H- ^ &<-- sort -ef aonoultatod mechanisms to do this, although ax obviously tke-y would ui'fr' cuM&tiJ r,A |vc. ga consult before^T It'realy makes, it very much simplier to operate the ^ to plfcy foe " cu**v\k><M<; " ft* 4 regulations when you ha'roillt g^ Q Tm^ho-r* nVii nh yftn-^niri Kn -|Vu3 1-p yTM1 g^- 1 i-'pinw nr .] ph^va -*rhi rh is the difference ifcx between the OSHA standard tfea and the British standard. Howovog.--fehat--gfr juat shows ynn thi i 11 111i_"r----- Hvit 1--1~ plnv .You will see that the number-gf man goes 0R-frfiQPDft4*ig Ttnd fehatt it gtaawUs .and-oo-^hio io obviously losing beemiae *k KBfcmriB *re going to bogin tn tiwxa t pp0|7^ Cl o^w anri there are obviously fewer in 1972 who have been exposed for long Ai A* period of time than there were in I960 because we are losing them. Ae--you can "loo thn t f n 1972 , 32$ e&e exposed at less than 2 fiber/cc. In iffitk 1936 100$ were exposed to greater than 5 fiber/cc and only 3$ now remain^ ia ii 2 in 1972 who ana. exposed aha axa axpaxa to greater than 5 fiber/cc. What this is -ahowiiag-yerr is that with time the number of people Maftig exposed to high concentrations is declining. It is jwat interesting to present it that way. 1fagy-ftPo n nYimfri "<if /--S?. ' 2 |/o.y always in t.Tri r- typ" ~ ** J'1iVnr. World War frooW' plaoo and Jzuring the auj? A the regulations were relaxed. Factory inspector's didn't care too much about what the levels were. The government wanted production asbestos omJ qxAiuiJm ypy, * was essential it had to be made.Overtime worked waa women were brought A ^' in to work instead of men and long hours blackout restrictions made it impossible to operate TT~nti 1 nti -hr And nil nrrrtn ?f thing" Pv's -pgpiO'eh im'World Way whioh I don't know what effect tk&t is going hfljjp m fo tfW'f to ^ on the follow up. //It is difficult to interpret the relevance of * 11 p*<y*d"dy the results which I have reported to you to m^dflEn conditions. What fW fejult we are looking at is a hotoohpath of bad conditions in the past and a continued exposure of the same population to changing conditions. What we need is a long term follow up of people exposed wontiaally at thi-e levol-4*efle less than 2 fiber/cc for 20 or 30 years, jj Dust levels don't come down in a day. "Ji fl**4- V cmd that is It takes a long time to get down to less than 2 fibem-s/cc p ^Voj/' tftwu.-jy A U U ci I o a plM i; af a the way in which the levels in the factory UCC 010208 have been coming down. 17 *sC Even people exposed after 1950 &re having substantially higher levels of exposure than are at the present time permitted by law. The thing to remember is that what we are interested in is diseases with<xn UvCideniC Off excess mortality. Shat- .yum fact'OTJ' may be build hero and otag-t-pg4u4-ng --Vi <a-ra tv, = t j 7 "b-rn y^i rbTP,,'lr f'^ th-" You Sidra don't begin to A see any difference in mortality experience , ywi nny riiim a .plight Wot! ot foiled "P ffope fss tiiff original after 20 years but you may have to 90 30, bO or 50 years with 0ooupcvtlonal sunoors before fehe-t excess mortality becomes apparent. +0 A This is why it is important that ynn keep records of medical findings^ Vert keep personnel records which are accurate with regard to iaa: date of employment and types of employment and if possible the type of materials me to which people exposed,whiok--arc! hasardoug of which may hfl Inn^n-Hnng ill the f^bTH "Tl j ^Yr ^ T"11 ftrt" j n ^ ~1 l~l a Strict control of your environmental monitoring and dust sampling and that you record these meticulously varying in mind that some time they will have to be related to the health experience of a group of people. It is only if you are meticulous about all that that in the future we will clear up a lot of the arguments and lot of the mess which we are in at the present time^ simply because our pxaiixKE predecesors had no concept of this type of approach b to occupational medicine. Occupational medicine the past for many^ea^s was the transfer of ,general practice into the factory jasb wf* a captive population mmI you could treat.btew#* What "Us my opinion that^ part of it that' & a fringe benefitwhat a*) fiiore important to me fx> nAtf +0 is to establish a system of keeping records abstract from these records +0 information analyze it statistically asid obtain an idea as to how tltfiv population compares with another population or the general population, C&/\ rfo alflW wdl out" yoyt^'riiJustty ^ J|f you 00 that you havo wa -idsa whether ~^ra-&gc me in any way xh (/penV&g jj^ imnppaadedinmg or i'-apari.f.e...g.....t.h..e......h...e..a.. .l.th` o"f t'h' e emp"loyed' phfrohn Mtd I promised that I show you that improvement had taken place doesn't show wb ^ but- ^ bold * very well, that's a man and those are his legs and what he is a pitchfork, UCC 010209 AO 0 9 1 3 18 Ishere Is a hole In the ground and he is standing on a big wooden drum . ""^his is asbestos and he is xhh using his pitchfork to blend it on a open %t's blowing floor throwing it up in the air and letting it settle,aad tfetXExxKg it about taW.Vfj the have all over the place. That was takofi place in # factory that I xatx just S&Sfftxy3SH talked about until 195^ and in some American factories that I fKe* visited in 1970 I saw that a* 141 taking place and in some American A factories that I visited in 1976 something very similar ibe was still taking place. And therefore that is another . Youx have got to be very careful when you read the world literature because working when conditions in different countries vary and stiixk some pst people axs: GtKXExikiHg as describe the horror and the disease associated with ""1--4~-" nnd th~ir finfliingr theyx conditions under which those people worked have to be taken into account. I could show you lots of horror have slides. I have been around the world and^ seen conditions and I got slides to demonstrate the differences between the TJ.S. somewhere like Haw South Africa, __ -___________ , Meebasa, India, Britain, wad Jit depends upon _ A' the degree of sophistication of regulation and of dust control as to what is going to happen to those people but authors of papers describing the effects seldom pay attention to that, and they weh will talk about asbestos or asbestos textiles or asbestos cement and never show the pictures of the factory or tell you what the conditions xx were like.a*d tint mr l?[n mil OSHA or NIOSH to say that the Rochdale population was always exposed to 2 fiber/cc and hence the 2 fiber/cc standard is no good because they are still getting lung cancer is a lot of well there I II ttvs * are ladies present/ll That1 s what happened to fcka job-it was totally " gricloxe^ * --* <W f>te enclosed. The drum is now in--thopc ^dit revolves ad""There is a *t> A fib/ S - bag opening procedure' the bagcare fed on a conveyor belt and ge^ into a* A.(h the drum.**! tips it into another bin down on the floor and- therfc. is G'So SInouW be all enclosed and there jss. no dust. That' s.,the wny'ite was In 1 - "When I walked into that factory in 1966 I was taken on a tour and A 0 0 c> A C UCC 010210 looked at -^be a#*G-fc*d where do you want to start, A at the beginning where the fiber comes in#i .19 . j t** I said -j-111 start * m take- may oamora and I took my camera and that's what I found. This of rft - course is very good fiber, tfeert is the best fiber in the world^it comes from Rhodesia. Turner & Newall owned the mines in kRhodesia and since i\*>T UDI they have not had any of that fiber. They have had any of the profits A and they have been cut off from their mines because of frhn 1 'Bgitioh sanctions . I wan wasn't allowed to visit Rhodesia while I worked for Turner & Newell. However in Jm Ilajinjb'Otac' factories there is plenty of this stuff The United States hasn't bothered about sanctions. Anyway this was 1966 these were iolla "Up bags. Every now and then you could see holes in them. Shippers used to love this stuff because it was- kssi beautiful bala-ecrd. They could put a few bags in a corner here and a few bags -a&& Wl^ a--qgraar in a hole there and they could trim their ships m 4 * - ^ *7--' that's the way it used to arrive in loose bags. The dockers had no respect -- A w'.i for these bags.they had big hooks and the way they lifted that jrk-ic to fW**. V / h-:- plunge a hook into the bags'swinging over their sholders ska 'efertrrk art over yj Hied h> jaw.-. the side to someone else.amt have /sc horrible mess and these t-hrings used to arrive at the factory a4 the chaps in the warehouse tbey did not have *-**' ~<-- quite as big hooks^so the little holes are there and fch?3r + o p11!1 thffie things add and hIiuU j iyu fuund waji a sdack like tliul mit'wthut y' jl ou can't imagine the size of this warehouse- huge warehousi aixfull of h fiber stacked to the ceiling. Wld AA It 18 months supply because they knew ^ was coming and so they brought at as much as they could and as much as they could stuff into the warehouse. There were bags bursting, there was fiber all over the place, fiaxk that's what you foundJ[t was an impossible situation and it was very very bad. That's fKe Vvfty i'S f' ot potyetoylfMt wha%-you find today. The bags are nowr. polyprophylenea ooyr ppooTlyt'h' y.no 6+d Solid they are pressuret-packed at the mines . Thb are all hard, they are like bricks, they are palletized and very often they are covered with an _ is ft*? a' fiben ^ Q Q -1 z. 1 additional plastic cover. Awtphat oemrs from Cassiar up in Canada * UCC 010211 Y*4<e sue 20 l4i-vc y iS ^ r- fehc 2 mines? there is one in North British Columbia and one in TToami C*J Ci^-ek. -- Territoty^o# Clinton goop writ's a nice part of the world to go to } j, c in January# //What we have is a story that is unfolding#ad phis is rather 'W A A j&i old slide xx it tells you about asbestosis beginning at the beginning of the century. The incidence declinl*^ in textile workers from 1930 onwards. I haven't mentioned insulation workers at all but the lung cancer incidence noted to be increasing in the late 50's early 60's aH*-1. ~1 (ptxb'tr/ a O.s'iuU , Asbestosis and lung cancer ovogall increasing this ** in the U.K. ^ ovvioa^ 4e\-' ,'i-e ^^ Mesothelial tumors luin^ recognized in association with asbestos in the use late 1950's-early I9601 sand- wonte- pr.oduo-i an -taken off lilt a thk during c\<rce(* **k.-e*l the War and a aaoeleratiHftg afterwards so that asbestos became a . Uy U+-{ j < i.jl irridfly vic^d material. It was cheap, hx easy to find and not expensive to mine and it was used in just about everything you could think of. With regard to mesothelioma in case you think we haven't had any in that factory, we have*ana I don't want to get into a long argument about it but that factory did also process crocidolite fiber and in my opinion crocidolite fiber is the most hazardous type of fiber and the one mostly associated with mesothelioma,#4 labile I was there I collected 27 cases of mesothelioma^sud,X hadn't seen any in anybody exposed after 1950. The average lapsed interval was long. At the present time Prof. Doll 's a ex stue^y ot ed T^t5v just before I left we completedgoing through our personnel record cards . tecods oi back to jl8 and collected something like M^y 30,000 people who had ever been employed. The group in Oxford are now going to check through those. They will probably take a random sample to start with and ikiec+voce them to see what they can find with regard to mesothelioma .whether ve K'e underestimated our experienceTor-whotheg Just to. tpy ana, eon whit thoy acm jThat is .the next study which is going to emerge from this particular group iii Oagfggd. I have taken up a lot of your time. I think it's over the hour and I must apologize. That is all I have to say. UCC 010212 A00922