Document JNVvQ2MOX7kMan7vLo5yqympO

TKIRP IWT-?N-~T""AL CT:?-~ or, rr7r?-:ocoric?ir Held In JOHAN' IF?U?-0 - 2*.AS- 2,5.69. rf:- (V - , -3v OF '--.-'T----TX n t-Lr -AFFPS Dr.K.C. Lewir.sohn - ,-',r5, P.''*!, r.T.H. <. A02 I 1 C tiCL(^l9326 UCC 009444 Third Internet!one 1 - - Iney-yc'"'' mis - Joh^rj'esKi'T'c~ - 2*> d , c * - 2,& . t -. Purpose of the Corf m-~r.c : (1) To tr_r..` tenet : rec'.-r.ised emert? in the v*ri ->? dseiplines (industrial redicine, clinical medicine, scimtists, engineers and airr.iristrs tive officials activel;- er.ta; e~ or r"?; rc1. and the administration of corpus-?ti*>n legislation etc.,' with view to pooling, on an international basis, knowledge, exr-rierc-F ana ideas. (2) To review the present state of research and preventive and control measures and (3) To determine further research necessary. '.embershir of the Conference was closed arc limitm to persons who received pers~nal invitations from the iecrt?.ry for Wes or from the Orraoisin.: Co"nittee. The invited members'-''t- ru-tered approximately 230, some 60 members coring from the United Kingdom, the United States of America, Canada, '''ranee, Italy, relgium, 'witzerlsr-'. Pirland, West German", Australia, Japan and Svodesia. "0 list of delegates was issued, but many prominent personalities wore present. The Conference wcs held under the patronage of the ministry of hires of the Republic of Couth Africa and the Honourable the Vinister of !-.ines, Dr.Carsl de Wet, was the patron or the Conference. Dr.'e Vet w-s the former South African Ambassador in London and has, in ad<?.ition to t: e above portfolio, those for Health and for Flaming and Development. The Conference was jointly financed b,' the Department of Vines of the .depublic of South Africa, the Asbestos Vir.inr Industr-- of South Africa, the Chamber of Hines of South Africa and the Mining Unions. Accommodation for the Conference and other facilities were provided by the South African Institute for ``edical Research, English was the only official language of the Conference. Pre-prints were available for most of the papers presented at the Conference and this moved invaluable in sllo-irm full attention to be paid to the speaker without having to struggle to >eep up with hastily scribbled notes. The pre-prints were published in a paper-back volume with tables and photographs. A list of the medical papers on asbestos with the pare numhe" in the pre-mint volume A 021 11 /W" UCC 009445 I is attao to tvis report. "r. :'l"ies will review the psrers '*!S+ 'adding etc., and I will atter.pt to evaluate the '-e-Heal' r-= r vs * The first half of the ca" of tie forf-w^----. w.. ^ai-istroti"R procedures artJ a n-iripc t-ur of tVe " ou--"riosis Research "nit. ve were shown the Library facilities bp ' iss ` illiams, who has produce'' a v^ry comprehensive bibliograph" of all papers dealing with the subject of Asbestnsis and its condic"ti-~e pu'"lisv'`='1 in the years i960 - 68 inclusive. This bibliography is available on request fro-, the P.R.F. Other erees of irdr^st w-ich wore see- were the new A.0.1. electron microscope whi^h has just be^n installed and the lust Corridor. The papers of a purely redical na+ure presented at the reference cap. probably be sub-divided into : (a) 3'sio Research and Animal experiments. - (b Rerrurir.rus bodies, ( c1* Pat nolo?-' (a. Asbestosis. b.Pl`ural -l""ues. c.i-'esot: eli-ra) (d) Fridemiology (e) Radiology, (f) Lung Function. (a) 3AQJC HAS "ARCH ALT Al'IIlM LXR~.IM:K?S: The work of "organ and Holmes is now well known. Their report to the conference on the use of radioactive tracer '-edds in the study of the biological effects of asbestos has been previously described. A possible explanation for the increased association between crocidolite exposure and mesothelioma may be that by this technique it car be shown that over half the administered crocidolite is retained after i months, whereas chrysotile has previously been demonstrated to show significantly greater solubility than crocidolite or amosite. This paper was essentially similar to that presented in Dresden in April,1968, The papers by Lan/er and F.D.Iooley at al both dealt with the problem of identification of the mineral core or 'asbestos bodies' and the significance of the bodies studied by these researchers. Langer described his technique for isolating asbestos bodies by means of low temperature ashing of tissue, individual /cont. ... AG2112 UCC 009446 7 Gicromanipulatior. onto appropriate substrates a1-* then subsequent analysis utilising the electron microprohe analyser. The instrument incorporates a scanning plec*ron micro=cope a*--" x-ray spectrome+ers which, together remit detection ant spatial display of ss-ple current, seeondrry electrons, bach-scattered electrons ant x-ray emission. The electron probe used is the the Applied laboratories HI motel. After cal ib^o + i 'o of the spectrometers with metal ant oxide standards, arc loses of known asbestos mineral types were made. Langer states that the results indi-ate that it is 'nssible to uniquely identif-each asbestos ve^ioCy b'" single fibre elytron nfopopo^be micron'-epical analysis. Asbestos bodies ur studied from = workman exposed to amosite, a workman exposed to chrysotile anc from seven cases, fror 'individuals in the general population not known to be exp-sed to asbestos'. The seven cases fro the general popul-tion were chosen 'on the basis of particle abundance'. 1,J15 analysis ware performed on 16 asbestos bodies from this group. Only one clearly possessed the characteristics of an amosite fibre core, 15 were possibly nu"lected on chrysotile but some discrepancies were found to exist as two separate bodies possessed characteristics of eroeidolite bv+ were somewhat atvrical. !'o clear evidence of unaltered chrysotile or anthophyllite fibres was seen. larger at;tee that his results indicate that amosite remains i'tr't in lung for at least 10 years; large bundles of chrysotile may also s+sv intent for long periods but chrysotile has a tendency tc split into very fine fibrils and specimen selection therefore (the . larger bodies in a population nf asbestos bodies) may introduce bias. Although 15 of the 16 bodies described above were possibly nucleated onto chrysotile, 'chemical interact! or in vivo would have +o have occurred to explain ou~ findings'. The possible occurrence of 'double' fSchaumann - asbestos) body coalings on atypical bodies from the general pt-ulati-r. m?v o-0 of -he factors affecting analysis as well. ^cont A02 1 13 UCC 009447 Poolv c 1 fy. T: the alPsl3ric ^ i- t'ivA +.pr,lr: ir'" 4. va^/^T'*^ r^* vo'*'' $3'+"i?r2c^''^2'''" i r T*gr^Tq pr?.^*i?? 1. " * . *r t'i I''**. +!ss*j" 'f,','r,r'' s ssr.'Iff+ .\r/* fibrss "*' c rr^'-r"* ^,- * tv ^ - -r- 1 ^-r* i ~ i vs "* r- L'~. - n f tt. c - ^ ^pr3 ?"o *}" $ y for X`'J'' r^viPr beer. sr-?.rsely distri ut- thr^u *'"? ti?i`u--. * ^;-ic `co ;.i-".! -akec t. e so^cimer.^ cbtaine- unsuitable for furth-r * *; '"' e'ec* on r'if''racti'i:, Focley V ? 'eviseo n se"''r'''siy ashing pron^^'v'- t** ---ove "ontcoinants. ?h a shirr o ` thin histological secti'r vc rvin ;io to 7S microns in thickn^-- is the only other t^ch* i~n- s'iit'r-b'e 'V nre'-arinr .fibres sai bodies fo~ examine+i"r with or r'-'Otr"r. "inroso^re. An advent-ye of *h~ alkaline di' = stiv" tr.r rir1? is that "~uotin o' tt= ey*"~=rteo "aterial 'or o'-ot^-r - - 9v=~ ir r + i-r. is eaoily ^rfoTroed ~s the axtrc?+ is ??rcr- 1" in ti'r form a sus-ansior, in ''istill-^ v ^r. j for* ie^~r'1''^ "." t'e c''r*"ants of the Fooler 'i`- r *' s " sops ^so-`OTS"',rta' , she-1;-2 ike ? = he^tos body. euh-divison of tobies has been i'o'.-ioVp<j v... j. rr'-oess where r'- the extracted K"i. bodies ere == ndvicr e - c6t " two r-n-interon-tin'" films of plastic to which they adhere, ' " =v the films are serarateo, the bodies r split ir two, an era 1' v e 1 one *he line of the fibre core. The sui-div'dea boa:- is th=n generally suitable for examination and its contents car. be deterr in--d. V,a oner discussed his work on the induction of tumours by the innoculation of various kinds of asbestos duct a:b found that with all types of asbes+os an appreciate portion of animale developed mesotheliomas. There was no difference in effect between the natural and oil-extracted forms of crocidolite. Amosite required a longer induction period than chryaotile or crocidolite before tumours were produced. Vagner concluded that when different doses were applied, the risk of developing a mesothelioma at a given aye could be taken as proportional to the dose. Samples of chr-sctile from seven different Canadian mines all produced mesotheliomas when ir decte-. Timbrell teas postulated that the early fibres of chrysotile when Inhaled are intercepted at bronchial and bror.ch.iolar bifurations where they can be dealt with by the normal lung clearance mechanisms. The straight needl&Aike r.r.d more rigid crocidolite and amosite fibres are able to penetrate the depths of +he lungs, whe-e UCC 009448 A02 1 H /eo"*................ they are pipji" `r rc?T*+ *'- eir e^ti*'. ' 1thr tvis pr^li^s to arcsit? rr^ci^olit?, ~rl'r `'T'o^i'''^'i'1,*"i th.US fr r 3. t1? ~T~'" reS''1*'"! I "*~' , i-^S't~,S l-"" - " ir^urti^r rerind ?? " es ^rihe" ir ex^^ri^rt?! ? n i " 1 s 1" ray be t'* ans--er to its arynrertl'" ~irira1 res?t.r.eliora rroducirv' effect* y ;--'torT,*OTT^ i'cur parers were rer-b ^r the subject of 2sbeotos bodies* general'*' r^f^r^ed to b" one on^ all .s femu ~ir? "'"'cdies* 1 a''l Cross ste^te" +^e hall 'rOl ir.." do.''ri'" ir-' $yT'r,if"on+? designed t-1 de-'c,rstrrte the oTi('ir nf fe^ru ~ir`c-,'S ho^i^g fror v^ri^us o^ranic an- ir.orf?ria fibrous na^-isls# 'r.t? reo*ntly published in LUe ]'w >"ih'lan~ J'^rral of \edicin in %n article by Saensler which derr*ns*T* te^ t'.= t in 2fi 3u+o"'?ies vt qt,i? * - ^ho^to'"' v^r f/vmd {rj opt? 's v.i o v*>" ^ CO"'' r' timal exnos* < '"c + -* 'sh'^^^Sj ** o^-e * - :-7t.nre chrys-tile asbestos could he defiritely exclude- h; el ctror diffracti-r. lias* fivre --* also *reairicrllv oy-l^dc.^ =. s th *1 aa--* . ^'is s- .^e--g au= '' t'- La-- v' a ''el* *'r,-t saps of b'-e fibres s ov-- `o suds': projected, were -efirit=ly arcrr.iboles - this f-*- a*' scV cf^s had no-- been exaluae^ or: ^jocg' yTMro"' oj5r*jor -at`eras wer* challenged. * further challeny* ta a--ss cane fror. Goldstein, who was unable to produce ferruginous bodies viT anythinr other than asbestos or rl?ss He used the following svbstan-es in a is experiments : A. nf ffine al Crirlr: 1. Chrysotile, Amosi*-e, Crociaolit" and anthophylite g^p-iiad by the U.I.CC. 2. fibre-alas*, pre-oared fro- frour.d-.*T fibre--"las* filter paper. J. Sillinanite. 4. Brucite. B. ff Vegetable Origin: 402 1 1 ^ /c""- UCC 009449 6. ?2.T_V,o''* A O , ^ p c ye*e v- yc> " - yoi" o *, ~ ^ *- ^ ' 7 f.r s "rst",n "ixer rill vr/^r - + - ~ .c r- c^r.r.iti ^r.s ar1" ^'*sr`?"-r ir.** tv p rcc"'" * 3 " * p-r-v-'^r : * ~ ^ ^ ? * 3 * a ^ 7* v*'' *> m- * " vfts C, of `.nine 1 Cri-~ir : 7. Tendon. 8. Aorta. "r. ?tp f,,vjTr: <"r = /, <^r of <:e^<*?sed Tins-- workers had ferruginous boding in their lungs and 'most cnees occurred in ?stes+os workers'. Lung neoplasms occurred more frequently in the cases wi+v' ferruginous bodies. The failure to I'ro'H-.e ferruginous bodies in experimental animals with anythinr other than asbestos or ,"l'ss fibre surnests t-?t t^er^ may be an optimal diameter necessary for their formation. Pelihoff aralyspd the occurrence of Asbestos bodies in the few York City population in two y ars. and 1967. They are studying 3>000 consecutive autopsies (1966-68) in 3 large "ew v'rk 7ity hospitals. The results of 1,973 cases have been analysed thus far, asbestos bo-'ies being found in 9&2 (47.7' \ In 772, they were few in number (1-/0; in 170, they were more numerous (5 or "ore). The analysis of the lifetime occupational histories completed thus far in 85 cases suggests that 'asbestos bodies are not randomly distributed among the general population of New York City'. Proadly considered, 40f of housewives showed. e?fces+os bodieo - 5<Y of 'white collar' males. 5Ct" of 'blue collar' males(nanual work) except those who had any history, however brief, of ever having done shipyard or construction work (all trades - carpenters, electricians, plumbers, labourers etc., Where the incidence was 7Of when housewives or white collar workers were positive, they generally had few asbestos todies; when men who had worked in the construction .ndustry were positive, often many bodies were present. SeMkcff draws the following tentative conclusions fro1" the above information : /cont A 02 1 i q UCC 009450 _7_ 1 V.'h1? ?'t-is v -'ries rrf? conH'.'inlv rr-P-'-n* in tr, lvjirs of pc'.1*= ir "ev v:r>' tr.^ir ''cc^rrer.? is r.-'* s rar.Ho" ever*, but to an imrortart extcr:t occur'-- rel;- t*c. 2. "*h* construction one? shipbuil"ir.tr i.rdustriss ?.r* rict ^cto-tial sources of direct ar^ indirect occupational asrs"o? exrosi:re and, epy^cially if possible neighbourhood an*"' f-:~ily contacts are considered, could be responsible for a lar-~p pro-portion of the asbestos bodies found ir. routine argosies. ywen c-'prsrir.-- Pr i. ci^^n-e of -pbantos :- -v`e lungs or in-'ivi-'uals examined at .tutopsy at the P-ur- 'inai Ics-ital 'r jaf ?y the-e v- - n-1 significant -'iff^rence in the percer-ag? of cases havir-* -nsbe'tos bodies in f-ese two years, 53 of 10'' w=re positive in ant nr I0n in 19*'"'. Por individuals to --eirs of =.-e or pore, :n of 81 (<? ^ were posi*ive in ia*t* as arairst 57 of 95 ir. l~-c~ -1 ', ^he a-oi-r.t of asbestos used ir. the cons-rue*i-r. ir.-J"'=-tr" ir. lt,c an-' -hat used in 1967 repairs fairly constant at (? of the *-t=l iTMnor+. The cp-ov+v ^r asbestos -''-eumT'tinr, IQ20 -- IQ69 has r.*n lr.-ly ir. product a in which asbestos is ' locker-in1 , as floor tiles, roofing felts, asbestos cement products. If the construction industry is +he ma.ior source for the asbestos fibres i- asbestos bodies fo>md in "rhan areas, then, the findings in 1^3^ and 136*7 should he similar because the amount of triable asbestos -products usod has not chanced. Pelikoff states 'If i + will be confirmed that urban po-vlaticns 35 - At years ago had asbestos bodies in their lungs as nf-en a such r-pulatior.s do now, and if appropriate pathological studies will demonstrate th-t mesothelioma was indeed uncommon until recertl", there will perhaps be less reason to expect that the current fi"din,- of asbes+os bodies in the lun--s of the general populati-r is a bartinmr of future disaster, that we fpp e. wiJespread epidemic of i-sma1, "hip--er^ are r-'-str'ieti-'o work appear to be ir -ost nrrent r.ed of "nri'-eri" and '-ygiere precautions. In their rat^r on 'The I'etenti-r. of /sbes-oa in uiesues', Pooley et al discuss the results of the multi-centre survey of asbes-os bo-'ies which they initiated in nctober,l?6f to estimate /cent.... A 02 1 1 7 1 UCC 009451 the frecMen^y w s * ' "i rn > f cV; -,g ' ihh ' ,* Z. rp post-mrter, in ^ iffcrer.* e*p~'t'7, * ical arca". r- n r + "n p r''h 0 p r^ f* intended to cov ay th-' 27s.n: f*2yv* *'* no 11tc rural -,-eas, * r- urban ereas of v-ryinr degrees of industrialisati ?r., to ( mr 5 areas where `he prevalence was known to be very h ' <9 centres chosen and the r**s"lts ere sh^wr. in Ta:le 1 ! f^T7,rrripj <ll?Sg,OW Belfast Cardiff. Lorchester Dublin Finland GaIvey London(1) Dresden London(2^ Liveroo-'l Vot tint-ham .. .. .. .. .. .. .. .. .. .. .. .. Timber Collected. Number Examined 7 /-s + { s_ .. 20C .. 19b .. - .. 2C0 .. 69 .. 200 .. 126 .. 200 .. 199 .. 200 .. 200 .. 200 165 to,f: ' ' ldfc - 29.(20- ' -_ 1^1 15.''11 ' 25 0,(0 ' 156 62.(59 ' 71 l.fl ' '.'ll ' 157 26.''19 ; 159 59(25:' 157 24.''IS ' 151 n.( V The authors feels that when this study is co^rlo^ed and fully analysed it will become clear how differences in *he frequency of detection of asbestos bodies at post-~orte" in diffe-ert geof-rar' leal areas cn ver" accordin'- to general lvels of air pollution with asbestos. These authors also rev>"=d tissue from lungs available in the 'v ittington Hospital .London from cases ''yin in. the years 1?^6(100\ 1956(1'''' and 196*-(IT'}. They attempted to see if the numbers of asbestos bodies in these lun< s varied in the selected years and to relate this v-riati'n to estimates of the quantity of asbestos in use. In contrast to Selikoff's finding's, in this study no asbestos bodies were found in those dying in 1956 or in the females dying in, 1946. The overall percentages of positive cases rise steadily to 20] in 1966, a figure which compares with the number of positive cases for London and the industrial cities in the multi-centre survey. The authors produced a mathematical formula which shoved thst the risk (and hence the number of positive cases' increased with the cummuletive amount of asbestos imported. Meurman et al attempted to '-'iscover whether A02 7 13 ,/cont......... UCC 009452 - <? - the histh decider* of l' *" oq-~=r ir "'i''l~r.d is i- =*" = v=" associ* te wit* *9 fre'cer* "a r,f p^r^eto j-t'-'pc t* lungs of adult rir:=, be=r;r i* ~ir~ ** = t tovao"t =-v~ki:\- - = * also be te^en into ''~rsider=-fcipn, ^cv r^opd thaf **v=*o oon9"'v-f'*''' f*i upland ~ ~ o--"" r~ *o oo 0*0 = 0 r~;..p.ppp- wes Mob, *^'t it he.s ber s foo z l*rv *ir ir sbrr ^rtrcri to the other r.ortbm ccurtri s ar/ tb=* o^lv the TTnited consumes more tobacco then ^inland. kifty consecutive Ivr*' career c2S-*s cor'ing to autors" during' *hr '-"ears 1966 ant erl,f l*fv s=rved as +h basis for thi~ study. The next autopsy case of the sere sex end s-e^tc within ^ yp""e' without lur.o rtercr v- = taler as a control pair. The rean ere of the lvrr "?nrr cs and their c~ntrol nail's v"s 6* "?rs. T^er v*r d6 rr 3= i worer. in each group, \=bes+ns bodies were fo r in the lur.rs of 0C* ) of the lur ;ani;r grou-r and of 12 (6/h 1 of"th control group. The~e is no significant statistical association between +he occurrence of asbestos bodies ir. the lur.gs and cancr of the lung, On the ot-er hand, this study seers to give sore support to the view tht combined exposure to tobacco spoke an-* asbestos dust could cause a rise in the incident of lur.~ cancer. A syncarclnogenesis of asbestos dust and tobacco smoke hes r.ot yet been established, but data available at present show +t=t such a possibility must be taken seriously into consideration, (c> P.`THPLOGY : (a) Asbestosis : Tevelopment of asbestosis differs from that of silicosis in that t'-e areas of fibrosis in the lung show.when carefully examined,according to Dr.Vebster, that the fibres and ferruginous bodies are to be found in groups and they have no direct relationship with the areas of inte(.titial fibrosis. These bodies and fib~es are in fact still in the alveolar spaces and the appearance of marked fibrosis t ir addition to th fibrosis or th alveolar walls,` consists largely of spaces in which a desquamative alveolitis has become orgsnised by connective tissue. After exposing Verupt morkeys to different types of /cont......... UCC 009453 A 02 1 19 1 10 asbsstos t 'r. *rr`? * ---t* c'" ^ j C a q q C 3 p Vo c * < c i ^ 5 "'o ; **r +/> ^ s * ^^ f br?s is f ^ :nd T*^ " * *'*' p \j*V ^ ro - be it^nise*'4 T^is rl^+ivl" simple irverti'--4-7 ->n *"?y be ^ T6?t bnfih to nr-th^lo; is4-* ir.v-'lvf/ in th no^h-TT*" -v biors,r die^^eis exposure. tvI'* 'ran-" fibrosis a+tributsd h-> ?cbest^s ^b^ rleural Maqu*s : _ ? r^fesoor Thorps or* ^is^ussec the pe thologioal developrert of pleural places. br^fes^or " bo-"pson states that on* of the striki'-" features of these plagues is that the5* ?r<> no* ag?n^i?ted vi+h r-l,urel adhesions ar/ w;-.?t lac''* is - explanation of their oathoreresis vy a rears which does not involve the likelihood of pleural adhesions develorind-. nurol plaques are fo'-nd only on the parietal pleura and only in "*ry special parts it. They ar* r^t f^;^^ g.t +u eoex or i' e * C"'et/>r>hrer in arv-los an/ are si*ed anteriorly only ex^epti^r? 1. y The- are fo'T/ ' n the ne^iet^l rl-sur*1 ov** th ribs s*n^ n^* -',rer the ir>r-^',ct-1 re^i^ns excert oos'ihiv hers are vrrtevrel bodies Sr.J thir 4'^"ens,Trs pcno<!> r'H.o-- aja s*rn L';* por+ion 'the di S`r'v:ra-'w anr' '-v*- or. +he --"e.-vl-^ n^r-i # Tv**- 5r* relatively r^rc wa" th re'T*io*v*^i'"*" rJ a^e sey* frequently over the l~wer ribs posteriorly an/ laterally. Celcific?ti"r occurs in *h.e centre of the risque. The s^l sirr.ificar.ee of calcific- tier is tvat the plaques have teen thre for sore tire cr" thet the collaren ir the centre is de_er.ercte^ end devoid of nuclei. Routine chest x-rays will denonstra+e only e- to 1?; of these pla-ues. Thompson considers that the growth of these plaques cones from the deepest portion furthest from. the pleura and tvct resothelial cells are not evident on the surface or elsewhere. After examining biopsy specimens of such plaques where the process is at an earlier stage of development, it is clear that the rleural r.esothelial colls take no part in the formation of the plaqje and merely cover it passively. Thompson feels that the plaque in fact is not a pleural plaque but an extra - /oor+..., A02 1 2 C UCC 009454 rl<='jr^l rla^ve ?r.' Ss the mepothelial crlls tak r.o "art i" i^T + v?t rX^rv' ^ srs ^h. h**"iv -- ~ali--"s.r* resotheli^m^s. *r u^^ers'-'le. "Fh'v~rs->r c^:r'*p_*c *v?+ 2 - " o thr ??hc^*'0'5 fihre-.^ i^r th' ''*' vr " ^ tir -*pr,-e to asb**oc ho^i-s# r.ov fro- --cavity a~d t'-e movements of t'-e lurm, sr:^ lst^rall''' Thev would *o --,-'0 d ov^ \<r p--* <= in *vp erect vesture oooutied Try most hum.ae he:r.~s for 2 /?r-is of the day *rd laterally for *h-_ rpc-aining l/lr^ d'rir. - sleep, ?r.^horpsor stresses that this invitational iovr/.-sv^ and lateral movement of sharp asbestos fibres in the lung is -possible vcijn^se of the coincidence of *h->-et variables : the sh=rr asbestos fibres, the soft easily punctured structure of the lunf , and +h cons*ar.t notion of the lump-. This -'nvr.ward and lateral roveoent explains why pulronary astestosis, unlike other pneumoconioses is more o9rked towards the bases. Thoopson also feels t'-ct this explains -why mesothelioma of the pleura is seen most frequently to-day in subjects with a slight or limited asbestosis as th=re is no narked fibrosis to impede the downward reverent of t^e fibres and their emergence fron the lung to the pleura. he also feels that it explains why mesotheliomas of the peritoneum, and possibly carcinonas of the ovarv ir. females are seen more frequently in people with slight asbes+osis. The proposed pathogenesis of pleural plaques is that some fibres by this means can leave the lung. host pass through soft tissues auch as inter-costal muscles and the muscular portion of the diaphragm, but others are held up by the hard tissue of the ribs or the dense fibrous tissue of the tencir.ous portion of the diaphragm or of the pericardium. The localisation of pleural plaques at these sites especially posteriorly and laterally is thus explained according to Frofeseor Thompson, f c' The Fetholorv of Mesothelioma "here wen* tbre-- tapers Jeali-. - th * subject. The paper by cluok-an was heckled and openly crit-cised. It wsS an ill-conceived attempt to dispute the work of the leading experts in this field and in addition to being non-factual /cont... A02121 UCC 009455 m & m 7> - 12 to a large extent, was of no scientific value. Professor Thompson attempted to sb-'v that the diagnosis of maligant messothelioma was not as difficult as the literature led one to believe. He felt that malignant mesothelioma was no longer rare but that until it is diagnosed with confidence by the ordinary pathologist as a routine procedure, we will not be able to talk about its increase as we do not know its present frequency. In his paper on the subject, he discussed the findings of 17 autopsy caaes.all recent,and mainly diagnosed during life, as well as over 50 positive biopsies, which included 10 of the autopsy cases. Professor Thompson's argument is based upon the rigid adherence to the currently acceptable criteria and he feela that by following these criteria there is little doubt that nothing but malignant mesotheliomas will be diagnosed. He questions what proportion of true malignant mesotheliomas are excluded in so doing. The presence of blood-spread secondary deposits no longer exclude the diagnosis of mesothelioma. Professor Thompson suggests that pleural and peritoneal mesotheliomas behave differently and that only peritoneal mesotheliomas usually conform to the old criteria and have absent or limited secondary deposits. Professor Thompson believes that malignant mesothelioma of tbs pleura has a range of malignancy aa well aa an average malignancy. While there are cases with virtually no secondaries, there are examples with extensive sprsad. He suggested a simple morphological classification into encephaloid mesothelioma and scirrhous mesothellnmi. The encephaloid type is tbs one that is usually illustrated in naked eye photographs with the lung encased in a bulky, soft tumour mass. It is a very distinctly type but is tbs less eammao of the ' typo 1m the pleura is eludes by stating that lm mnj individual oeee the absence of a history of exposure to aabostoo, the failure to demons trots pulmonary asbestosIs or to demonstrate asbestos bodies ' ' *" "h. .. in the lung, should not be regarded as in say way invalidating tbs '7. v diagnosis. He goes on to say 'we do not know that asbestos J A02122 /eont... UCC 009456 1! . is the "niy carcinogen concerned, and it nay well be +bat( exceptionally, the usual r-sy'nse + n + he rre en',e of ush -ts fibres in the lunm is lack!nr and asbestos ""o^ies are r:t ferned. In two eases describe* by hi*" efforts were ~=de to demonstrate asbestos bodies by basal smears and by multiple sections from the lun- bases and elsewhere witho-j*- success. The third paper on t'esotheiioma and asbestos by -'shcroft and Kep~leston, was a reiteration of the paper which we pre~=nted ?t the Dresden Conference, ano this work has beer, previously described. The summary to this paper reads as follows :- 'The association between reset1 eliona, asbestos vooies in the lun and ocupati'nal exposure, to sbestos inhalation is confirmed from an English ship building area. The matched case-controls showed a surprisingly high incidence of exposure to astQs+os, though much less than in the cases of mesothelioma. The survey of routine necropsies reveals that industrial exposure to "sbestos largely accounts for the presence of asbestos bodies in the lungs of unselected cases. Accordingly the risk to the urban population as a whole from general atmospheric contamination by asbestos may well be less than was suggested by earlier pathological surveys without occupational histories, but the extent to which asbestos fibres are involved has yet to be determined. Wide variations occur in the numbers of fibres and bodies from different cases of mesothelioma. The 'stio of fib-es to todies is also vsria'-le,thou h fibres, many f them small, tend to rrdo-'inate. 1 (rt; FAFS7T' nK SPirglQ'Qm.Y : The pauer by Tr."evhcnse was exec4-!;' the same A02 123 '-nt... UCC 009457 I 1/ pC f f! * * V>ter ^ * ^ f* ,-1t*(1*' a 5r>-` r '--A -r6:o"t8(J, no r.v -'r**ri = I. ""'b? p = ro'_'? ^ *"' -?^ fir.^ir.^*? is +vs * ir. r.en witV sh^rt se vll ss ir. f wit', ? cn~ exrosvre th'~>*e w.?= a statistically si-~nif ieent ex^^rF uf r-p^ths fro"* oancer the l"r~ ->fvJ rltvrs and o'pUer ca-c^T eft"r p period of =t least sixteen y ars rtJ elapsed fro- fics* exr-osnre, :'x"eaw of da+we f^or '-esnir= tory des>-" '""-wi pnlv ir men with a 1-nr exros-re. Pr.i'ewt'ruse stated t^at study of the autopsy ^a-^rjB ant ristolo.-icsl material fro"1 pni\"ect reuegpga ^ a-^-'itt -nal pleural and 1* peritoneal "eootheliona.tr rue t'-inbs that these findings suggest that t''.e excess i->s*N fr-- othe- cancers was due to the occurrence of peritonea] nes-'t:elioma v'-.<eh have not be=r. identified at +he tine of death. . n-p.r.ilsor summarised the rr; ent position in the "nited 1* reborn making special reference to the mes'-`*helinm.? rp -istr which is being rein+'ined at the ''rc-pt-m "'srital in .n, " nsot' s 'apartment, with, airport frcr the Trt*m'*i ""1 prenoy for "'esearch on Cancer. f.50 cases 0 nesnthelieras of pleura and reritonewO sue provisionally reristered in the Ur.i ted rir.rdo-, c~ vre iaarogpd before 1055. In the 'u?r; 105* to lr>to) we e added, with an avers e of F per an~un. and between 19s* end 1 c ' 4 , 135 were registered, riving an overage of 27 per r-nr. The annuel fi-mres for 1965, '66, '67 end *68, are 42, 32, 5 and 60 respectively, Scottish cases registered between the years l??"1 to 1967 number 8S. There are 43 cases with information on dates incomplete and there are 28 cases as yet alive. Pr.Gilson next referred to the epide"iologi"al studies ir. dockyard workers in Great Pritain and especially to the work of Surgeon -Commander P.G,Harries at Pevonport and the publication by Sheers and Templeton in 1968 of the results of a survey of a 10^ sample of the 15,040 employees at I>ev~nport A02 124 ,/oont,.., UCC 009458 - I* - - ockyard, rr.*h-ere cmr eluded that there were 6 b ~en ^*5 ' in whom there was evidence of changes probably due to exposure to asbestos dust. Jr about 5 out of 6 cases the effects were limited to pleural thic'-erir.,-. Often there w; ? li**!? o- no disability. 'r.Oilsor. finally Jiscussed a survey of pleural thickening in. Chest Clinics which was organised with the heir of the British Tuberculosis Association. This survey showed tha+ there we? a slight but unimpressive excess of positive his*ories of exposure to asbestos among the eas^s of pleural thickening. Further analyses ar* now ir ptonr^s? "?ing the medical histories to see if there is a group with pleural changes for which there is no adequate "edical uistoTy, ar.c vhethr in this sub-group there is a relation to past exposure to asbestos. Dr.Selikoff reviewed hi? findings in the members of the Asbestos Yorkers "nion in the Tew Y->rk area end delve-1 dee-ly into the composition of insulation materials and the quar.*iti s f asbestos used in inr-lation material* in the "nitad rt---tes in the yars 192r' to 1?65. Be also analysed +h? use of a?ve?tos insulation by construction type in 196 and showe-* `tit. by far th greatest amount was used ir rarine construction work =rd ir. pc -r process construction work, i.e. power plant and b->il^r rooms. The use of asbestos by insulation workmen in the TTnitod qtates in 1969 was analysed according to the volume us=d, ( expressed as 2 percentage of the totalJwhich in the case of asbestos workers v-s ?5`*;and the application(which was expressed as a percentage of time' indicating that insulation workers spent tj- of their tine in the application of asbestos insulation. Fibrous rlas? was the other mador material involved with -15; of the volume total being applied for d(? of the time. Of +he 6?2 members of the T'nion, on I'ece~ver lift, 1942, 3G0 were dead by Pecember 31st, 1968. 1 ir. 5 deaths was caused by lung cancer, Despite the recent rise in prorinence of mesothelioma, this remains the most *^vestns-ass-'ci?ted /eont.'.. UCC 009459 - 16 - re^plasr ar->r ~ irr-.iat:nr. w^r'i-'^rs, ?r,?aIi'-rff h^r. wgr.t "'r t" rlati^r.s>i^ v'.`nicv h gxisb "'rc^vep-n <3 -- -<v^- aiid career ?",i''r.r ?!- irnS"lat,`*'s'' v"'T'^a"? : ^-*.1 ~ ^ +. hirr? iv-Xf' ?'"'**'**** **^4oe '.rQT* e*rvo~ *'oq ^x'oectsd* f7vpx-+v - tv-' +h* 7.?0 n o - *<s \r*~o du^ to Tr'cS"t ? - i , 6 ard 1^ rerit^neal, Peritoneal resothelioea r.? + seem to te related to oirar^tte gTohinr;. In the three rffc? ol* T'le^jr5! res *,theli`''".a i"nr *h** hav s'-^hir-^ . historis, all had e^-O'ga oin,r,7*ettes "r*,?elIho^r etrtec th?t +he** h?ve conti.rv^d *o sore deaths due to cancer of th*> stomach end colon than ex-oct-, ~oas +o sta.^e howe,fri" thr* the rrat^o is ^rlv ^hrae ti~es expected, and with s few deaths, the;- are not ye* c"trin of *he relations in* ^elikoff is oonce'ned *'*?.+ the ir.''i''er'"e of cancer of the rscrese =nd orophEryngea1) cancer eronr asbestos workers will be increase^ , . T"lrtv de?*''s of t'- = J8C wer due to resrirahory insufficiency vi*1- cor pvlr'-'ale. Pr.lelikoff has analysed the imrcrt?tin and use of crocidolite into the United States ar.d finds tht very little crocidolite entered until World ' ar II. The eeben*os used i-` +b = United '"tote? was almost entirely chrysotil*. The 1 arrest asb'-stos manufacturer in the United States first used crocidolite in 1929 for sheet packing, not insulation, Accordinr to ~*likff, this company never used crocidolite for the manufacture of insulation at any time between 1929 and l.'6e- employing it only in two product lines mainly asbestos cement pipes and packings, Turing these same years, 1920 - 19^0, more than 267,000 tons of chrysotile were used for insulation purposes. Selikoff concludes therefore, that crocidolite exposure of United states insulation workers before 1930 and probably before 19dn is unlikely to have occurred to any significant extent. The 22 cases of mesothelioma which have been 9en in the years 1947 - 1966, all occurred ir insulation workers who /cont........... A0212R UCC 009460 - 17 - began work befor 1??C, lelikoff armues that if a 1 'rg- la tent perioJ is required for asbestos induce4 mesothelioma,then in his series, nr'oidolite exposure alone cannot easily explain the rmesothelion's seen among insulation workers in the United States, The moral which celikoff draws from. this is that these findings should engender caution in reiving on other asbestos varieties al'--=--s to he significantly less likely to cause mesothelioma, The relative mesothelioma hazard for each fibre variety is still tn be defined in humans. At this tine Selikoff's data suggests that it would be prudent to regard all fibre varieties as poter-hielly hazardous, and to utilise appropriate industrial wyi-iene measures for all. A number of short papers on the currently available results of epidemiological surveys in various countries then fallowed. The paper by Avill on the results of asbestos exposure in France contributed little and must be discounted for lack of adequately presented factual information. Kiviluoto and Meurman, in a brief report on the results of asbestos exposure in Finland, once again we~e unable to find a single case of pleural or peritoneal raeootheliom- in their series and also did not find e higher incidence of gastrointestinal cancer in their series. Professor Vigliani reviewing the results of his studies in Italy, did not relate any new findings and presented essentially the same facts and figures as those which he gave to 4 he Dresden Conference. t'cDcnald et al attempted to carry out a retrospective survey on the cases of mesothelioma which they ve able to trace by vritirm to the members of the Canadian Association of rethologis's or the Cueb"c Association of Laboratory Physicians. They found 16? cases, 111 we-e pleural, t7 peritoneal, ? pleural and peritoneal and 4 pericardial. The diagnosis was supported /cont.... A02 127 UCC 009461 - lp - by sutopsv in tvo t' It^p of t^ crs!? sn^ b" tio^s" i- *',-o i*' p n Te'- 10 - 3 v " ~`F , :'`'riv*~ *h. ? 'Pf:'"" l"""'*' t l-" ~ *b.e ='****'' ' annual ir.cib-ncr wre 3 p*r ^i2 ! ior por^l^ ti ~r.. -' aTsTre?!1*-v'^i-'~hoT' i'' -vo(-' fifO th^ir in Ontario1, ,r'.c or ir tb rect of C2,r?a'4?'"P,Q) t - }Oh 9~~ affair. acc^vr"*'L'~ for r-tiob or th differ*" ce. T'-or in th fpx ^c*ri^i^n un^pr tb. ~ ^f no differ!'!" ',vt `t1"r-'= '-i 1 a ? yo SlV3"P 1", P f,X'?c'S# "ar --7*2ir. aQb6st*5 tex**l r^^yf^ctyr. 't'" inrtall?. ti on *f brske-lir.ir^ s or ~s insulst^rs, wT,e ?ivl for rest of the excess of cases over controls. "ine or rill vorl'rs rade liable o r.*T.ibuti~r to tb< diffrrce ar" orlv ore person , a hardware storerar., h?.^ vorhe^ with asbe"tos-c"er^ rr^^u^ts. 7b tire be`veer first exposure and deafb fo** *v IQ capes ir th definite or provable class ranred fror if t^ 5n yes^sj / rr wbr ''rrhe^ on the for lerr than /i "e?.re had intervals of IS, 26, 2~- end ** -enr?. Excluding 6 co=e<* and 1 -ine aid rill Ther in each control who lived ir rir.ir.-- *ownsf only ^ men and 2 vo<-er. had e-rer lived within 2f Tile*1 of ?r eebe^os nine, o^ the * w-=? a cs?fi S we'e ir. control rrr \ an^ 1"' ir. o'r^r'l group P, The poaeihilit'1' of contact ~s a result of sore other member of the far.ily bringing home dusty clothes from ar occupation involving the use of asbestos w?s also exanineJ, Again excluding 6 sen already then-selves occupationally exposed, ther** was one case in a female with 'definite* home exposure and one male in control group 3 with 'probable' home exposure. In addition there were 26 persons with a 'possible' home exposure; 10 were cases, 9 were in control t- and T in control group B. In both males and females, persons in the primary lung cancer group had smoked considerably more thar. those in e: t; r A 02 I 28 /cent.. UCC 009462 - 19 - the ease or secondary lung cancer .-roups. The 19 men with definite or probable oceurational exposure t- 'b*stos shove*' no ereat differences in snokin* habits from t'-o "?se= without occupational exposure. ".cfmnald et al conclude +hst primary ralirpnant -esc*helial tumours ere vr' rare in Tanada and if is somewhat doubtful 'nether there has beer, ary true increase in incidence since 1959. An association between these tumours and definite or probable occupational exposure to asbestos was clearly der'nstratd by only a minority of male eases and no female cases had any such exposure. Lesser decrees of occupational exposure, indirect household contact and residence in asbestos nir.inm areas were no more frequently reported for cases thar. c^ntr-ls. The excess in occupational exposure was in the rarufactur= ano industrial application of asbestos rather than in mining or millir.r. The'e authors surgest either that chrysotile is less associated >011* nesothelial tumours than other forms of asbestos or that somethin* in addition to asbestos is necessary'. If th^re is an a^diti^nal factor, their findings imply that it is not cigarette smokir.-". The paper by T;r. Mcfulty on his Australian experiences is now clearly acca-doric as the asbestos nine in ' !ittenoon,`-.'e~te'n Australia, has been shut down. "is follow-ur survev of the nen who ."rked at the cine and in the mill is of interest as it beans out the association between asbestos exposure and lung cancer. Since June 195&, 1^3 men who worked at Witteno-ur. have developed pneumoconiosis. 41 were "ill workers, 29 were underground workers, 6 were both unde-ground and mill wo'-kers and 24 were men with othe" si.rificant mining- experience. ? -en were excluded because of lack of clinical detail. It would appear that although working conditions were poor and dusty from the beginning, the-e din not cause significant lung disease while the production of fibre remainec lew. 'rtirued poor conditions and increasing production created a situation whe-e pulmonary disease began to appear after relatively short periods A 02 1 2 ..... UCC 009463 k 2: exposure* "^e 1 *%lr CX"*? 1" "''"= ~-7* ' '"-r.. rl r.*<9^ i-->a ^ * -. ** rc"-fl \jr C,?^ '-p-h * V ' ^' dJ v-- -- --_ '-- n - -- c - 2 a r'lH X A t r r * f} f^V;* `ir/ '' fpr'"- ^ "h^ 2 2 -- + '--_e TVSZTS^? ?.|?6 ' '*I'V *'? r*,^ ""' t v; v- ' ' * r' ^c v-- ;-. ~c ]';< 2' ""2)rr 1 r-2?'"`fi? h.rv t*3*"! fr"^n~~ y^pl'crc the- t^vrjs^e^rlej ^ ~a" ir this ?,?',*i*? enveloped til" *-r'5-' rlc--rel ff'S'/'"S, ? ni1'vi''UE]ir u.,* fj^o'- vein t''ro_v'sis wit- l".nf: ir.f?rcti-r., r-a* tier vr.s n~ "xrlanatio- for '''= ofcr ( tVp c- `c or"; o'- * i cn-' 5ilVfcpci*f 3 - r W- -1*0 e j-. +vo dis.'tosis of lv.nf* dfrss f*i* 1^^111!* wi*- *ih? ohrs* ravs. ^h*- ra^hoior" v-'? ~1'--'S* inveriavIy been that of silicosis, wi*h tvrical nodniatio- '-m r:3rs:v ribrosis with interstitial fibrosis and ?.ovestos bo-'ie-. rno dr*e, 2 m-- h5v ^o"^'-'rie,J 1'trf c?.rcr, both vsr heavy s-ov^rs. ' pleur-l mesothelioma oocurrd -'" s raar wr>e,; in the -ill between 194? and 19/=, the tu-ovr opr-rir.: i- l1-'", A particularly bad ferture vs t* persistent us of rine tailings for road svrfscing, whioh exposed tovnspeorle =r.J children to loose Just cs''*' = irinp fib-e. Ir. Touth .' fries asbestos is both mined and finds its wav into factories .'here manufactured products ar pro^uceo, Ac-ordir.r to ?r.'debater, li+tle is Known about tbe fect-ries and works nsir.c asbestos but ? considerable amount of inform? hior, ha = been accu.--ujated on the results of asbestos exposure in the -ir.es and -ills. In South `fries the high proportion of pulmonary tuberculosis in the patients with moderate degrees of asbestosis presents problems to the epidemiologist and the mine medical officer. The f.outh African Asbestos 'humour :-:efrence >ane 1 has defined the criteria on which a mesothelioma car. be diagnosed and, up to the end of 19^9> 179 such tumours have been classified /cent.... A02 1 3C UCC 009464 I -21 as 'definite resrthelio-a'. study of *!-e :-e distribution s-owo" +vrt 'II 2 sT*? PT*'>'" r*? f*T*^"r* 20 * 0 QO ,,'02.T`S '' J PVP ,',r "t>r* ' pi ! ^ , r.Vebster feels that the i_istol^, iool fe'tnr = of a pleural biopsy specimen ar sufficiently characteriseic for the diagnosis of r.es'tholiora of +'-'e pleura and even exfoliative cytolopicsl examination of the pleural fluid will five an indication of the diagnosis in almost all patients. Of 1?P cases, in 10r' the diagnosis wcs rede ?r g specimen of needle biopsy of the pleura only; and in a further 27 cases the positive pleural biopsy was confirmed by ev+oysv. In 5i cases the specimens anarir.ed were fro-- autopsv exar inc~i^n only. In 1* cases an oner tho-pac-tory v~s ne'e forced. The--r '^re, in It of the I7d caseS <jf mesothelioma the lanel were able to satisfy the most stringent criteria for diagnosis. Of the 61 autopsy cases, asbestosis was found in 2^. In 1/ cs=es there w=s no evidence of asbestosis or of bodie.- on histological examination., s>rrugir.ous -oiies were found in the histological sections of the lun s of 1 ce'^e in. which there was no evidence of an interstitial fibrosis. In lq patients there wee no report on the presence or abse-ce of asbestosis. Dr.i'ebster feels tha+ bec=use in 1-' cases no evidence could be found of asbestosis, this in itself might be indicative that there was not a direct relationship between asbestos exposure and the development of a mesothelioma of the pleura. A = tudy of the environmental and occupational histories of these 1-' c?r<=s of mesothelioma is of great interest and, indeed, confirms the iacv of a direct relationship. Of the li8 cases in which the history was hr.own, in 2A there was no evidence of asbestos exposure at all. There was no doubt that -eat of these patients had ha,J ar aerociptio*' ith ive Torthern Cane and tha* a -ore detailed *udy of this area. A0213, ^C'lr.t.... UCC 009465 2; i V Z T'f' E r1VI 1.. 1 T ti1'" - r > , y; - 1 c ~ `' ' ' :,t.: '^hster lists ti.re* cises *';er' the s.--'* -'. - W" s dv? *o 5LT'`"'E 1 t0 . Th^r-r ?3? c rf3 r'"'t ' c- in ^.'.rtr>r de*ril* 7: the iiscussirr w: iv' ;':1 .tw ..nmir tnn not0,1 th'-t v,(*inr'>*i -m7 sj^^fit- t rr = :', -'-,r ^ er.c'.yh ir. tire, -rr that proructiT w-s -s lar in quantity :r f->r l.ortr- >st blu* see;tor, c-n th-; t '-<;r-= ar.ssite to be with mesotl^lio-? ti-i? a---3~"'L tier vrul- by r.ov have been oci -- : Ir.Veester was ci-.reful to -oint out th" t other o'vrsjr wer-- to '-e fovn` ir ?tur.dgnn* ir th' "o'-th- 'et C~~ - 5ri r.er.ti re* iror ?r." mm.'- nect specific-lly. He sur este^ that the -art - ? -yed : -sfce-t->s ir. th1- develop-ent of a mesothelioma and irdea-', :t :: tumours of th' respir--tory tract, cay be indirect end cay well carrr th-r irec4, or rcino, pr. to retrinec in contact v'ich -h-''"--';- r-s- imtory tract for a lory-m period than when the crreino<"en ir The cire"t caroir.cper -.a - - r.ot be ? sir-'le subetaroo, an ; the cases frrr: th*- "or them Cape su; ect that another nine-s' , such as man ?rese or iron ray play a part. ~ueh ar associater. nay well be considered ir t: ose cases of mesothelioma ocourrin.- in shipyards ana dockyard- one in the ir.sulaticr. industry. This hypothesis has been pf viously stated by r. It m.rhius. (e) RA'.I-nIO;v : .'he section on radiology v*. disappointin'- . Alt'-.on; - the two papers by Solomon on ine radiology of ascertosi* and the radicle-u cal features of diffuse mesothelioma were pood examples of the use of commonsense and powers of observation, they contributed little, in my opinion, to the problem of the earliert changes which one would .associate with asbestos exposure or, if you like, early asbestosis. Tr.lolomon considered f.rst of ell plevrsl changes, and, secondly,the appearance of noncalcified pleural cha.r- :s a- opposed to calcified pleural plaques. In e=-ta:lishe- cases :-f asbestosis fine fibrosis described in 5 cases,nodular chen-re were /cont......... *02132 UCC 009466 ?.r.J ir n c?s?s 2 bil^-rcl s^ii/ fibrosis -v. x-~"v rrodM c \ r.r 2 ~''r'r'r'i -riti ~"r. w* ~ '~,V?::Vpv<r',i *?--' i"tr lrr!'id? -'i* ~*v?.rds 0f~ f>ihTr,2is "t'C'"1-'11 "i". c'^rr?? f 5^ - fosa*-' 12.' C t ** ^ * t 'r'" ' * t r * - 2 - ? i, 'T. S "7 t'.'V '"?' 2 ``S ` ? '. 4- p.~ c jpqoc - v-r i''f.*"+ lo!?i''r"t ' ? c f iT; <iT,rciic v = f * rr---<=> lr?fs>ncp^ ` r. V?I^o1+ t^t effusions,ft " ^ 1 cn2 r"1"+ inns, ~ c *'^ tv ? t i ^r *hr 7i9c,.'ye,t>ifitftfill22r r'l21'v* ' ^v^va'"i**p sri^ f'ie"' '-2v,*?2 '*2?'"*es ?usuid t<? rsf*s.r7" 's si'""'i'Ti cr t* oh=n,~s r-^jpr*? who 3 ' is + ^T"' or '"' = ct`,ss xT-^s,'r. ohrr "?' -pit* v'itV. 7 i ~ ~ X *? hj?tnl^ icr2 ?f s?"re fi wwr si? 1"' X'-Vvs* 7r 1 '*iTic* ^iO'* *>f th Tlftvr,2 i? v 7"+ -pP'-> fe?t-*i " *'*' ssbpctoi? Fxp^sur1?* : -'`CCT1 T** i- a'-fte *OSi?|COT3V'v,c,rT T'l6VT,?X qy<^ 2,'r*t=' i-Fi`*-r'" $_rJ sIpt**' `h cl ^iar* t"1 *h ^ i^r^^sis. T'c^'ilsr,rne^ron^ *? c arid r,aaP-iv ^i^rctic ch?'".'** ^r----p i*- v'rtion ^inp a^.*5 "^9r?s iir.pir fibr^i? ''S'-"!''' sir7f5""rry pv^'tifor" end ^r'~"'lar patterns* Tve x-r*"' <* " c*-, -c - v c r v> p ^ r>o ~ + 'np"'" t i on so. 111 t ^ +y-p df?'`npp o/* f'.Vrc^is if *'"r Ivn^ '>p'9 hist^lo.- icPl2;% 1,''`vi2.`,r, + <* ^ --Vc *'"st ^ j c v - / + *i ^ ' r> ' ~ rs ''6*i*>vr'+ ps **+ ir y--r" pn'`/%v,''CP s s w^lX r r *-"-' Jc c*'" t"- "'lrttit, of x,r,r'Svi,p r^ 6Xp"spd 'in Pyo,** *'!'r fir' ^ px"'"'s'-rp -p d?ct*1 fc,'`p r,:i~"4ts 3 c+u'K* oT to n "* x--r^v fiir.s of* ^51 w^T^eT'C ovg'4 bo* so PT'.tbor,hplXit ss: ?t^s ntr.i-~ '1Hr c_'r,0';v stu^is^ xstp1,1 or f^ro^r wor'^srp "'nly^ .<* the *?' ela?8<a tine frcr> first exposure w?s atout 2r yerrs. ?or an ir^ideree s*Tjiy nf hyslinp and calcifi0" plaural plagues ar.^nc people '^t 'ro"r; to have bean exposed +o tbe fir.dinfs of 5,818 cor.secr'tiv? 'h<st y-rav examinations ir ' rrive* ollnio vere coded, 180 of the r^t,al of dir erses w*re radiolo*'ically normal, vharas 250 had nlevral arJ/or pulmonary ratholo y. Pathological changes ret st^riVv-table to -sbestos vere ''reid^red *.~ t nom?.!, Ko asb"; tosis was iiis*errible in cse and +hna ' r icj-'n*........... AQ2 Mt UCC 009467 2d - about 2d: of the pethol"fieal cases, or I" pleural o'-nr s vf re obs^rve^* Jr. a ^ition* i* s'*'vulo bQ + ^ - of c-: ses ---if'- lv.r.--- rsr.'-er, tk< pvlrT.sr: f;"--"no *slf 'r 1 verv sli hi*. ' '"?h ''laT3T=,l t-rin't'er*r*' J`c'? vi rh s^vcritv of' l'j"e^n r ^'I't i npb5*.Ei?'' that a bourn j.y of css-s wit; lur.,- c'o-r. -f of ever grade III s' o-" no tl=ursl thickerinr. Ir a series of l'T,r,00 x-ray exari'-etions ir Finland ,plevral thickening v- r the -"s* oo--or. raoioloeioal findir.p after cerdiesc er.la r*'e'"er +, aortic s-Ierosie, and pulmonary emphysema, . Hyaline anc calcified pleural plafv.es be a much more specific radiological feature. fr.Kivilvotc o + s.tes that in pra-tice it . transpires that a correct radiological interpretation of pleural lesions is a first step towards diagnosis in cany cases of pnev-oonriosis. where a routine clinical examination has not led to ary s-sri-io- of this disease. Frofessor Foblip discussed the protle~ of asbestosis in relation to the International else.ific- tier of radiographs in pneumoconiosis end describe'-1 the new DT Cr/Cincir-a closoificotion which he proposed should be adopted in future for * = classification of chest x-rays in pneumoconiosis. ff'1 LrfHC PF1MTIC-N rr.l'argoret Becklake presented a most element paper relating x-ray changes in Cuebec asbestos workers to lung function tests. In 1966 an epidemiological survey of Quebec asbestos workers was started to assess the effect of exposure to ehrysotile dust on the health of the workers. Dust ex-osur is being evaluated from dust counts and. Job classification. health has been evaluated from their most recent chest x-ray, fror lung function testa and from a respiratory symptom questionnaire. On the 31st ''ctobe-,156, 6,180 men were employed by the constituent companies of the Quebec asbestos mining industry. - /cor.t. .. A02134 UCC 009468 An sre- = tr?tified rar.dor sample of 1,027 sen was selectee for lur,,~ function tests an*' 5FJ were tested the followina' syor. 7r this cri. ir.al sample only "1 men (?' ' werc considered t- he"e radiographic evidence of as'ce*osis, (only ? bei^g place1 ir categories 2 or }), although th sample was weighte1 for *v. older ser. with presvnably lonrr exposure and more dust dise?rc, second field stud" was carried out in 156r to include all oC years and over r"t pre**i*v;sly tested. In Pr.Becklake*s report the comb ined result of these 2 field surveys va? o-ir.s* dred and the are distribution of `he 1,0'? suhjee*s wee irvesti---*od. "he rest rece-t c^est x-rev of eech subject w~s es^opse^ in don=>:l Ky an i*"ter"" +1 "ra 1 r^^pl of 6 readers. The TI^C ^lincin'eti cl?ssif f O' bior was used, Tr.'eoklak itemise-5 *he lunr fun-'*inr * end the "o' =ure-en*s v.-hioh were rade in se-nence. T'^e1'* tests included studies bt"h ?t rst arc during exercise and t%e ..r-w. ronoxide diffusing caps city was measured fco^h by nears of the single troo*!" teehnione and "he steadv--$ 0;. ep rethod, hip ot.s racteris*io ne^^ri-tic*' of all ej'h--d'*.'1* of lunr- volure was present only when radiological "harwes w=re definitive. The first lvn? v-injno oeao'Tpoppt to be si -"1 r<cPT' + l-r ppfestgJ wae the poitel ppoacity, ^oth the forced pxtira+ o>*v -"l"---'' 0,7s cpwwnHs, siy the forced exrir^torv v"l'r*0 f,l seoond, *endeJ to fall ir unison witv the fall in vital cap"ity, a find r.p ir. keepinp with th- view tha* expiratory* flow r?ts are vol->r"- dependent.- The ratio of p--7. to FVC expressed =s a percentage was essentially unchanged at all radiological ecteyories, being ev=n grea+er +han -'ortr-l ir the established cages of asbestosis. These findings underline the fact that obstruction to the airways is not a feature of this disease and that, when fibrosis is advanced airway calibre ray even be increased. Dr, Fecklake measured the C<~ extraction which wa.s reduced at rest with category 1 changes. However,because restir.r ventilation was increased, t^e -'iffusi-T of carbon-monoxide retained little affected until x-ray changes were advanced, 402 13^0... UCC 009469 - c. g r 9 -s'. T?' + V" S T f *'T' *, 4 ''/ * * p' _ 'r-'-'lV^C -O^^prt ^ n * O T_ C ~1 ^ ^~ r - p ^* '. ^ ^*"9 " 9 9 '. f. p". 4 i 1? * *'!. '',r~ , t4" - -7 + A s >r ''. c r - + es ^ 1 ' ? .i " -c. i + ^ -. i~y^ ^vic>p i*s^lf V** f* o ^ ~ '** r + e ''"iv>* 2. X 2 t.1" ^ ~13 3 ^9 ' '* Vr .7" . -i * -- ^r rer^rts inrsirr^Ti't of .*35 pxc'.r^/c -a-.' -^ cpaf cti p+ an earlier ratiolo.-ioal st:ye than impairment of gas excV; ---e 2* 3TS S "t It is of > rest interest th-t the two furcti." n.pe surp'-er.ts which most closely paralleled t e raci?lorics.l development of ?=>--- tosis wer* vit*l cs pa*it:* an-' -e- hi Istio t 20' k-. per minu e. It is of int^est that these two t<?p^s''-i*-gi capacity and erercice ventilation' are technically easy to carry cut. The; are thus potentially suitatle for wiceoread aprli-stior - or; ? loryit'.yi'-al h-sis. Ir.hecklake's fi-dimes are not incompatible vit the view roo t ` r"~'a irTMer-t of ras exchar '? pp ~lctpt i- `ts '' fp 'r' er t' c es rl iesh fvnct-'or ch~" n~ ir ?pLc '+osis, precediin* ever x-rry char. ps. hvpvf i+ d-pp ar"-ar "h? * hhcre are rompers?*-tv mechanisms w'*-ich can rca'me his rh?n--e apra*-"r + a* a later ct~r than th changes ir. vital capacit" wh-rt- sh = desr-ite=, O'" ~ -v V' "''yr'iyrp --" , Ir this rerort I ha'-e attempted *o review ve-p--hriefly,irrortant racers wMch wprp rroduced *t the Trterrp+:^r.a.l Conference on 7neicocor.iosis held ir Jcv:ai nesburr between ** 2^rd April end 2nd ?'.ay,19^Q. I attempted to he brief hut inevitably ir * task such as this I feint myself rereatir.r laryely what the individual authors had stated. Tor this approach ' make no aroio-" as I feel that I dr not detract from the value of re appraisal of the authors findings. /cent,,.. UCC 009470 A 0 2 1 3 rj '^r i~ rf **c<? pv*rp"al'` i;sef^' , In fact, ~^r- -t':\ *vr visi* *' rrsdsn* I w-c y-i -06+ --ar>,. 0 +v,; lcdirv* "pres ir t',t fit?!'3 nf lr.J'',f"*'r'? = ' r^d i c * r.e ?fid 7 wp? ind9^ gbl, or +wr ^cessions, to or*" `Tit'.' i`c to the d i. ?rjssi ^o t visi4- t^ th--' "'are ?lue Asbestos 'line a* '"rjrar was, r, ^rte -*? *h hiyhli-hts of this journey *- ^ovth --frica and I c?~ y so- that all of us vh-* ?av this mine were extremely impressed by the vigorous action vhic' th* ^vr.ers hv,f t'-rr to introduce the r^ost ur-to-Jir * dvs* -^r^^ 1 retho^ s ^r*vayner, ^urir- "h* C^nfr^r.?e, pet3 p sn^ntane^us tribute to the ~ou+h .'Tricar. Asbestos ''inirv' Ir*;vs*w' for `'he role which they rlaye^ ir the or -a ni sat ion of *Ve *' ->*-< *v pCr 0 c-i^* -*-h her" v-"-i which h?T '-,*t irT"1 * ' c. ** -- fa^t'-rtss an-' "ills t-' ~s?V the*4* safer piece? fnr *- v^rV, '"lV-. e fi .*nt i f 1 ' o^ -ea+j*-` yre "if s 't :*h !r'Vdi ^ j *rir'K, ?"w,o ' ' r,iop,^+ '-ei. 4 r-? -if th ^v. Phtft tenderer o^ p,9p,r th c^^shere ^ ~ r cr-"" 'r..- the role of eshesto? bodis^ ir- the ^r,^-1 populati^r va? to consider these sr ar index of ocou,r'pi'i ^nl exr^sure ra^^er environmertel exposure# Indeed. F"ra''" ent as f:.r as t^ s-" t>-'* t^eir v^**V hpo reverled trot -""ere ps-es^os ''odie vc-re* n. 3" oor'nstior'l bister** vo.s elnoot i-variably obtainable, " There still remains 3 rrert deal of s-e~;l2*i^r. 2= to *b.e role of the vari-us tyres of asbestos in the cav.saM or of reeotbeliors of *ho "leur= and peritoneum* Once again it appears to be emerging that the concensus of opinion is now ir favour of the theory that not all veeotheliovata are assooia+ed with asbestos. Asbestos nay even have an indirect rol" to play in the causation of both lung cancer and -esotheli^na rerely acting as the vehicle for sore other carcinogen such a? tobacco /c->nt... 402137 UCC 009471 1 26. sccke, iron, ran.-anase or s->-e eh-" *race element, T*h$ i* ir. +,Utf' t'r-'Mp- ">f =sbestosis and Its complication? ua? highli 'h.ted by the lar--= number of epidemiological s\jr'?ys recorded a-'T'aar to be tetter equippe" that o*uers ?->r ~e frying- out surveys and it is to he hopeJ that the less informed will take note and take ever;.- effort to improve tl-eir recording of data and their statistical analysis of the data they record,, in order to help to clarify the "nop-alies which still exi^t with recard to the geographical distribution of ashestosis and its complications. 1 If T have any regrets with regard to this visit to "cuth Africa then they ere that I was on"1 le *o . cross the border to Bhodesia to see thc mining renditions there and that I was not invite" to see any asbestos works of ^inps within the ''"public of s^uth Africa or the Republic of fvactlaod. I hope that if the oooasion su"uld arise in the future to pay a visit to any asbestos mining country again, an opportunity will be afforded re to visi* the v5ri"us facets of the industry in that co-;rtry. H.c.Lrr/rKscHN, B.Ch. E.I UCC 009472 AU2 1 33 T?-V.r 2- ~ - CT^nr-KCF - r'edic= 1 Parers on Asbestos ?'7IC srd ATT-TI 71: '^.Tr'TT ?he use of radioactive tracer re*hods ir. the study of + h Molorieal effects of asbestos - A.Forsar (''.r'.^nd A. do Ires * [ ) " Microprobe in the identification of asbestos fibre in lungs - A,", Lanrer in.".A.) The ^ete^ti^r of .'.?besto? in Tissues - F,?.7^?lev e+ ai 'tuples ?f cytot rtj.ic effects of different f.orrg of ? srt cs -- 'T "# ::smin r`+f>n (r.',.'..) The induction of tum.-vrs by the irooulrtio'- of vcr^'r;" of =shes+^ d*;"t - J.C.'a^ner et al Cfrcinofeni* e:-''ec:to F# 7r->ss (r.' asheotos in experimental animals F'.P'^iv^r' --ft -- Oririn of rerr*:`inous (rV'V*y Fern"oin''us b 5 - 5 r'.'/^lrstei*^ ^^, - ***1 ce ^ "" *he '*cv v fit'* no o'.! la ion ir. *vo periods of *ire - T,f. "olihof f ar.^ "af^yler ran-on/'T'!' ' _ qXae*^g b^die** i r +ue l^ivs of e seriao of rin^isv Ir^f* career rati^nts - L,r .'.errman, Y.Horr.ia, !'. sons.Vi and 0.cutinen (r'inlaad' P- TE^I^Y (a"1 the T- atho.-enesJ s of 'bes*os':s - !- r ^j-ot-pr fr, (?' Fravlens i- *bo pathogenesis of ?sv,es4`oeis I'1',3,A.'1 'v' P'*ho^-eF's of oieor'l plac es - J, ~,?v..-,-sor, I'-.A,'' (Problo-s in +he ^i*rrlo?is of reso+belioiop of ihp pleura and the problem of asbestos as i4? cause - J.". OlucVman (!>,.3 ' (<3 Fatholorical ^iar-n-e-fs of re 1 tenant rresef-elioma of pleura and peritoneum - J.9.Thomson (^.A.) (c) Keso^rheliona and Asbestos on Tyneside - T, Ashcroft and A.b.Heppleston (U,K.^ gPIDgflfl XY "orn" observations on '-sbestosis ir a "actory population - W.J. Slither (U.K.) ' Study of the mortality of vorders employed in an asbestos factory between 1933 end 1964 ir. relation to the latent period, job and length of exposure - F,L.Newhouse(r.K.' C4 11 40 ?o: a? ii 75 QO SO Q3 /c-nt,... aU213j UCC 009473 i - 'IP Lis* of r'ed'cfl Famere e",r*i'''ied FFni?-T,''L T-Y 'ecu*..,. Asbestos hpalth hazards ir the "rited '`irr^o- - recer* observations - J.C, Gilson pT Mortality experience of .Asbestos insulation wo-'<ers 1945 - l?c? - T.J. Celifco.ff et al (l\a- Results of Asbestos exposure ir. 'ranee - Jean Avril(Fr) 104 Results of Asbestos expostir* in Cir.land - "?iro Kivilunto( tin land) and laurit:evrman( Finland) 107 Asbestos exposure and its results in It=ly - ".0. Viglianif Italy'! _ Bpideniolo.ty of urinary malignant mesothelial tumours in Canada - A,1.TcTonald et al (Canada) 10? Asbestos exposure and its results in Australia J.McKulty (Aust) 113 Results of asbestos exposure in Rhodesia- M.Gelfand (Rhodebia) _ sbestos Exposure ir. Couth Africa - T.Vebster (<'.A<) 116 The relationship betve=n mesothelioma and tuberculosis - C,A. Sleggs (S.A,) - RATI 0100v Radiology of Asbestosis - A.Oolomon (c.;,.) 12"? The Problem of Asbestosis in relation to the international classification of radiographs in pneumoconiosis - K.Bohlig {'>' Germany) 132 Asbestos : Aspects of its radiological features R.Piviluoto (Finland) 1?7 Radiological reotures of diffuse mesothelioma A.Solomon (S.A.) 140 LTING FTOCTION Lung function in a random sample of Canadian asbestos miners - M.R.Recklake et al (Canada ) 123 UCC 009474 Ail 4 S' Iv