Document 82dVVqYVrEvgp3oMg9Kj8p7Re

Office of Origin TURNER BROTHERS ASBESTOS COMPANY LTD. To Mr. John Waddell Mr. J.A.E. Clogg, T. k N. Ltd. Rf> Copies f u: JW/PM ANM/JFX Your R*f> 15th November, 1965 Wyera Memorial Lecture by Dr, J C. Gilson, 2Znd October, 1965 I had a copy of the script of this Lecture sent to you last week, and now 1 want to add some comments. I am also sending a copy of the Lecture to Mr. A.N. Marshall. First, this u.ust be treated as confidential at present. It is a Xerox copy of Dr. Gilson's own script, lent to Dr. Knox aa a matter of courtesy; it will eventually be published in the Proceedings of the Royal College of Surgeons. After reading it you will agree, I am sure, that this Lecture is of first class importance. It is the best and most balanced r 'lew of the whole subject of the health risks of asbestos that 1 have seen, and it is, of course, right up to date. You will note that it contains several complimentary references to T. B. A. , to Dr. Knox, to the Asbestos is Research Council and to its researchers. Dr. Holland Dr. Davis. The Bamblln referred to is the Manager of our Engineering Design Department , who has given several public lectures (with permission) on dust control in asbestos textile factories. Dr. Gilson is, of course, the head of the Pneumoconiosis Research Unit at Cardiff and Dr. Wagner, late of South Africa, is now on his staff. Dr. Gilson has visited Rochdale several times at our invitation and knows the work that we and the A.R.C. have done and are doing; he is a man of very high standing and international reputation in this field and is a good friend to T.B.A 1 think you may wish to circulate this Lecture - and <rhaps some of these covering comments - to the Head Office irectors. Continued............. o 1 / -2- I regret that when this note is typed I shall be away, so my secretary will initial it for me. p. p. John Waddell^^w1 1 t 1 o 1 > J 9 t I t Mr. J.A.E. Clogg Mr. J. Waddell, Turner Brothers Asbestos Co. Ltd. 16th November 19^5 Wyers Memorial Lecture by Dr. J. C. Glloon. 22nd October 1965 Thank you very Much for your letter of 15th November and I aa obliged for your consents. On a brief preliminary reading one cannot but agree with your remarks and I look forward to an early opportunity of studying this lecture more oloeely. Arrangements have been made to effect the requisite circulation and this will include Mr. Soothlll. JAEC/KHC J.A.E lu CLOOO i CONFIDENTIAL Mr. A.D.N. Jones, Mr. W. p. Howard, ' 22nd December I attach copy of the Vyora Memorial Lecture by I)r. J. C. Gilson on the subject of "Asbestos - Decent Studies on its Diologleal Effects". This document is, at. thir stage, confidential. I thought you would be interested in reading it and after Mr. Jones has sent it on to Mr. Howard, I should be glad if the latter will return it, in due course, to me. JAEC/MHC Enc. Cfu J.A.E. CLOCO * 7 \ K * k { J l 1 FVEJg IXVCKIAL ISCTJE by Dr. J. C. Cilioa 22nd October 1965 01r*a before the Autu&n Ueetl&g of the Aeeooletloa of laduotrlol Kedlool Officer* at the fiojrel Coil#** of 3ur*#oae, Leadsa A*f#r*no$ to local (Rochdale) altuatloa oa Pa* 6, 7, 6. Section* merited* o / / JCC/BS1. 20th October, I965, T"~ V'TTT I ~ 'FTsL ' rf*~'~r `Asbestos - Recent Studies on it* Biological Effects* J. C. Gilson, r.a.C.P. pneusocooiocis Rcce.rch Ur.lt of the Medical Research Council, Llanoough Hospital, Per.arth. GlCfiorgaa. ' * This, the aintlx of the unit of lectures to renew the seaory at Hubert Wyers, 1 e review of reoent evidence about the biological effects and health hasards of asbestos. X such appreciate the honour of being asked to five It and X aa euro it la an appropriate subject because Vycr* obtained hie Cla*c* H.D. In 19*6 for a thesis entitled, `That legislative assures have proved generally effective la the control of aabeatosls*. Hubert Vyers wee a t.aa of vldo Interests ana unusually deeply versed la the classics and philosophy* This Is clear frau his contributions to the 'Transactions* of the association of which he was the first editor* Also, froo the o?enlng rtaarle of the other lecturers la this series bp . those who bnev hi* well. 2 hove wonaer*d whether his Interest was sparked off by oy father who was his headmaster and taught classics at ' , * King Edvard's School, Simnjiam. Vyers's thesis shows a deep interest ia the individual and is full of shrewd observations and oosperisons between different occupational diseases. It also contains not a few a eculatioas of which one setae * ' O very suitable starting point for this lecture. He said (p.JJ), *11 is well-known that the short, dusty fibres of the saber coloured ascetic are the aast pernicious of all, the blue ecbestos occupies an intermediate position, both as retards year oa achines and effects on the lungs# and the wnle asbestos is least heraful both to steel end to the human respiratory aechaalea". His oonaent ia interesting for two reasons * the first, at the time , it was redo it wee unsupported (as far as X can ascertain) by any epldniolocieel or evpsri&etvul evldencej and aecondly, it was in a seals far ahead cf its tine because it is only within the lest few yeers that serious medical attention has been directed to the possible differences In the blolerleal motion of different types of fibre. ?r jTnT]r pretucira There are four *ln tyoee^of fibre of cocnerclal interest. They ere ; * 7 i ; &ri *mamA -291 fibrous silicates but differ ia composition. Chrysotile, softest of the flares, it t csgnosiia silicate with only & snail amount of Iran end is mined extensively ia Canada, Southern Africa, and Southern Rhodesia. There la alto * very largo production froa the U.S.S.FU Crecidolite and ecoslte are chemically similar and both contain Iren in the place o;f magr.saiua. Crocidollte it a striking blue oolour and ameslte le brown. Crecidolite coses free a Tangs of hills In the North-West Caps and also ia a snail aaouat froa WorthWeet A*utrails. Aaosite only coses froa the Transvaal. Anthophyllite is of considerably less ooarcerclal interest t-xn the other three types; it le a magnesium silicate but differs froa chrysotile in being less soluble. It is mined principally la Finland and in Italy. Table 1 shows the world production of the four sain types la 1962. The production of all types has bean rising steeply since the war and auch greater use can now be made of the short fibres to strengthen sad increeee the abrasion resistance la many building and other products. The elneral le now nonetently around us la the ceilings, floors, walls; In the brake-shoes and clutch linings of our oars. It is reported that there are at least 7,000 separate uses for the mineral ( H*--*--. y-m irropyy ?g ih AP?rsAea 2 will st-irt by reviewing soae of the recent exparlaental work and then . dlsuuee soae of ths now information oa haalth hasards associated with aibcstoa. - ' The health haesrd le prlaarily, though not exclusively, to the lunge and pleura. Earlier workers wore pustled by ths presenee of fibres of 109 ^ or longer la the lungs of sen or experlccntally-sxpoaed anlaals, sad suggests* that fibres gained aocess to the lungs by different scans from that of other dusts. It is no longer necessary to poctulste tills. Ths falling speed of a particle is the aost laportent parameter influencing lta entry into the lungs. Hy colleague, Or. V.Tlabroll, has recently show (Tlabrell, i960) that the falling speed of airborne fibres la related to their disaster squared but net closely to t'.eir length. Thtf very long fibres B? have a slow fulling speed provided they are very thin. This is shown by using an aerosol spsetroaeter which collects particles according to their falling speed. Flg.J' chows a record froa this instrument. The stall spherical parUclas of wax are about 19 y ia diameter and unit density, end here the ease falling speed as the fine asheetoe fibres several hundred y long. The fibres are only about 3 in diameter. O f iati m &-x4j itthM MUM N^l -3Thoee findings arc very relevant to the ptns*tr of the airborne dust which f should be r.easurcd to asnass Its inhalabillty and toxicity. n tha past too such attention ha* been paid to langth, too little to dianetar and aerodynanie behaviour. ftrcriL--vtH ;Nrt?sla The new work in expertnafitel asbestos!* * after as interval of cany years -- it producing tosa interesting results. It Is ssv possible to corry out quanti* ' tativa inhalation ex?*rltnts in anicala. By this scans Wagner and hi* colleagues (196*5# 1965) hava shots that chrysotila produce* lass fibrosis then anoalt* or croddollta for tha sons doss by inhalation and this appears to bo dua to tha such cor* rtpld alielnatlon of tb* chrysotila (Flg.J). The mice for tbit aor* rapid elimination Is not y*t alaar but it cay b* related to solubility. That* findings in sxparlctntal asbastosis accord with tha obear* *<a.on on can by Negalaehaidt (19&5) and other* that lungs with aarara asbastosis oftan contain vary UtU# <tinar*' oosparod with other types of pastacccnicais. TUa iapertanca of particle length on tha daeelepnant of flbrotia In still not eolvad but work by Vagner (19Vi 1S6? 1965)* It*lt amt Mill* (196^), aaO . Carls (1964) in aavar*! snlcale spades hat shewn that flbrotia of tha lung in promised by flna particle* or vary short flbra*. fibre* nay still bn relatively era f'brogsnic for a (lrcn cats Van tha sort ooapact particles (Kloatarkotter, 1965) but critical ex,:erln*nts to Vst tnls in lungs hcea not yat bean aehisred. V# nasd asparinants of tha typa Ring and Nagelschnidt darclopad to study tha affects of oast, aurfaaa arcs, and ausbar la axparlnsntal allloodi (Zaldi at al 1956). Hew tha aah<*ato: produced fibrosis is still uncertain* It appears to bs lass toxic to tha phagocyte* in Uctua culture than quarts. farnls (1965) suggests that it nay be a direct stimulus to the fibre-blasts, Its action on tha phagosome* in the phagocytes, which hava bean show to to* dsssgso by silica (Allison at *1, 1966), 1# now being Investigated. Tha nature of tha asbestos body - a tern now agreod internationally to bs ora appropriate than tha asbastosis body (U.X.C.C. 1965) -- has bean elegantly investigated by Eavis (1964) with the elactron aleroscopo, but its inpsrtsnes, if any, in tha pathogenesis of the fibrosis regains obscure. frmtla - an iron O prou-in coaplex with about Si; ircn _ i* ?Tct^L'.y aa important constituent of U toil*##. It la pocalbie that the fixation of iron in tne u:.uc- in thla /(FuoslUr ot -1, way cay contribute to the appearance of the cht r_diograph. focent vorx/et our Unit in othegriypee of paaucoconiosia baa sn~-a a cloaa relation bctwetn iro oontent of the lung and the oategory of ulcpla pneunoeonioale ia the rediograph. Although aabaatoa bodiaa now seta of laaa icterest ia tha aaveloparnt of f'^rweia, they hare be coca of such greeter Interest aa wa epaw ~lologleel **'*-of exposure. rg.frirrr.Ml cnrclnajcncaH At the Uea of tha aarllar work oa experimental aabaatoaia tha aociatioa between aaoaatoa exposure and oanoar had not baao wall established. Little attantioo wee, therefore, paid to eebcatea aa an experimental carcinogen. tha poaiUcn ia now rtry different. Kany investigations ara ia progress following tha preliminary rrport by Vagner and hi a colleagues (1?62) that thay are abla to product aesothollal tumours ty intre-pieurel inoculation of aabaatoa. tha aarliar work has baan fully eonfireed by Vagner (1964) la standard and paoiflo pathogen-free atrains of mu. Twenty eg. of aaLcatos injected into tha plaurm haa produced meoothelial tumours in a high proportion of aninala. Thia la ao for chryaotlle, aaoaite, and creciiolile, both natural ana afttr extraction of Ita natural oil by a alngla solvent. tha investigation a survival experiment - la not y*. oospicte aa wa do not yat knew whathar thre ara algnlfloant differences la tha nuebar of tumours produoad by tiie dlffarant ty.es of fibre* 80 far umoslt* haa preduetd tha laaat. Tha yield of tho tuaoura haa baan unexpsetly high and further experiments ara now ia progress to Investigate tha affaeta of an&Uar Intre-pleurel doaaa and tha affaott of tho duat inhalation. Under animal experimental oondltiona aabaatoa, tharafora, appears to bo a powerful carcinogen. How It acta la not yat known. It la relatively lnaolublc, -onuina Iron, and haa absorbed on it natural olla and vaxea (Harington, 1962). It also takes up oil rvuuily from Jute bags while la tnaport and from othor aoureaa (llarington and Fac, 196}). It ia not yat a tall olear w.,t.vr t,,cco oila ara of any biological or conical Importance, nor ia It yot oleer whether the iron ia an important factor. Wagner* a animal experieenta, ao far, per&ape cake Will unlikely as the iron content of the chryaotlle la only x about ono-tecth that of eroaidolltf or aaoolto. *# cay axrect & at inerc-ta in oxijorliientil work on th* carcinogenic affects of as>stos. To help in this work tha producers of all the typo# of Asbestos have gcr.ercuoly agreed to help tha Ini -national Union Against Cancer (U.I.C.C.) to assemble at the Pneuseooniosls JUaworch Unit ia Johannesburg standard atcplse of ths sain typoa of asbestos, for use for biological tasting in aay part of the world. These standard sasplea will rasova ou- cf tba variables which at praaent aakaa con,.orison between tha rasuits of dlffsrcat laboratories difficult. Thay will also provide ataadarda against t&ich to oeopara aat/rials used in dlffarrnt parts of ths industry. htalt:! hATirr: cr Ar?~??s . A8u*st3;l -.trgfcnt.-oslUrn In the C.X. Zn his runsary W'yera (p.137) concluded, "Legislation has been generally ffactiYa ia controlling sabaatosis but not entirely". Z proposs to look at son* of tha racant evidence on this, but at ths outsat it la necessary to aplasias bow lnocaplete It is. V# hava no raliabla figures for tha pretuleoe* of aabastoala ia tha oeuctry, nor do vc aran know tha nuat-era of workara eon* tinuoutly exposed to asbestos; still lass tbosa intermittently or casually exposed. Wyars reported a study of daatha froa aabastoala ia a factory. * Sr. V. J. ^ithsr has kindly providad ca with racant figures for tha aaaa factory* Tabla shows that between tha two parieds 19pl-<6 and 1957"^* thara has baaa no striking chance in the years cf axposura or duration of illnaas la tha daat&s with this dlaasss. There has taca a aarkad increase la tha age at death. This ia in part apparently due to a vary striking chance la ths inporusca of tuberculosis, which vaa preaant la 311 of Vyors's {roup, but oaly of tba Bora racant croup. Tha absolute nuabare of oasas hava llttl# significance without * knowledge of tha populations axpoaad. Zt looks as thouch Wyars was too optlnlttic, but it has to be remeshered that th* second period includas tha re.ults of tn# War vnan long hours, the black-out, and tha dlfflcultlas of aaintananco aust have markedly inoreasad tha dosa of dut. Information about naw cas'S of asbectosis diagnoead by tha Ministry of Pensions and National Insuronca Panels alto shows that aaocstosia is still a real problem (McVlttla, 196f>) and that tha steps taken after ths Kerewether and -6Prico rrport in 19>D have not. ?cn fully effect, vo. 3Toils shcwu that caseo of asiestooia or*' atlll occurring In those vto entered tic ir.cuct:y after Ijjr and, ir.ciood, even after 1S5Q. It also shows that It 1* occurring lr. occupation* not includod In those scheduled. ' Table lr shows the contrast Uw<q the gersrel cswr.vard tr*cd of tha ausber of nav cases receiving cospensatioa for cost types of pr.c^secniosie, except esbestoiis where them la an upward tmad during tha last G yt-ru {H.K.S.O. 1965)* Thar# err, of eourso, feany factors affecting such figures, but they Ir.dioata a need for farther action and investigation. ' I That action can be very effective is show>i(?eble&^ ) by comparing tha prevalence of asbaetosle by yaars of axposura found by Konvathcr and reported y---** for tha saca factory (subject to lost reservations about population selection). Tha striking Ir-provsecnt is inprasalva and has leva aehiavad by a vary isorcssive technical ir.provesant la dust control as thosa who hart visited tha factory know. Tha aagrltuda of the prooica is aaphaslsed by Sar.blln (195?), that tha dust extraction of tha Cards ra^uirea about four tinaa tha power needed to drlvw than and that tha ooet of dust n.ntrol is about 71 of the wage bill. X think tha history of the efforts to control the health hat&rd aasoeistad with asbestos in this country, whan looked at nationally, denonstrates well tha failure to provide a continuity of research effort. Kerevcther and Price in t their dasrlcal work proved tha existence of a serious problaa and this lc at once to laproveaenta of duet control which have boas very affective in tone textile factories. It also lad to a ee.-.ooe to protect tha individual aopleyar and esployaa by a syataa of aadical exsr.l nations, but it failed to use tha results of tha aadical axanlmtiona and tha dust assetcaer.ts to sea wi:at was happening in tha Industry as a wliola. Lot us snsure that va dp batter new that renewed efforts are baing cade. Va need a properly integrated sohaae in which Information about group* of individuals and their dust exposure is analysed to provide a continuing ohaek on changing condition* in tha industry. Our National Coal Toard has already gon* a long way to achieving such an integrated sehane of res*arch and supervision in their dust problem (Pogsn at el, 1965)* There !e an own greater need fbr it in tha asbestos industry wfc*** there era ,tiU *tny ftoro unknowns for example, the naans of detecting early dan.-.ga to th# lungst the leportnnce of type of fibre! and the relation of dosage to _ o both the develo-cent of flbroala and tuaourt. ' it infiii i ?MfTatift -7Sttnulatod h;: lr. J. Kmx - who will lo;.,. '-o r-r.ooib-.r g f;r .At initifiv# horo - the V.rn* t'g,;<*at *et*.stift e'\",,nr.na in this country r.o..,. ^.i excellent sv-rt by establishing Vmir Ashoatnsiu R.-.ercii Council. fcoal >rov:"f. 2.4S boon achieved in exchanging inform tion on duct control and recently cn atandnrcisiag duct c/w-ling. Lot u hoys tie research work ticy uc others arc now doing will shortly \o.d to improved itethodc of nodical *u;er/liicn by r. iking the soot uso of lung function tosttnnd rsdlograph. Vs shall also need * c;c. _ cf recording and follow-up. Only in this way aioJJ vc get early proof of ths of.'ectlv<n*e- or failure of pr vontlve treasures. The investigation of the individual l- no substitute for otudyiih. U* group* Af^T**?"-* fycry. Prrrc-1-1 ,fr.-r:Tft An association between asbestosis and bronchial carcinoma was first aug..cata< in 1>J{ by Lynch and Ssitfc in &..!.{ and ahortly afurvt.it* by Clcyne in this ' country. The evidence supporting this view gradually accumulated in the parted! rv^ortc free .`iercwothsr. The pattern of change over the y*ore can ta veil aaen Table 4 foe* Dueheuun (19-C) Proof cf an association batmen exposure to asbestos and lung eanear case in 1?5 in Coil's study of the aorta11ty of s defined populstiou of eon in scheduled I Jobe in the textile factory (Coll* 195w) This study has now i*en sxvnded in ties and scops by Knox, Coll, an.-1. Kill (196*). Cr. Knox lei Kindly allowed ee to give you the figure! up to dune l;i. 1 ToMo"] Shove that for sen followed up in excess of Si >-earo.and V - worked bsfbr | and aftr 19r*f there has been s narked secular f.-ll in the saceaA lung eanear | risk. In those encoring the scheduled arena after 1JH* sen thou no axesaa lung f cancer risk in tho groups followed for 10 and <0 years rsapocUvsly. la tls ; voM*n there has been one death tnu lung cancer la which tho post aortca did not . show evidence of asLsntosls. . i The findings of this follov-up aro v.-ry er.ccurat.lng but sano caution is /period [ needed. Tho fcllow-up/lt still not very Lonr; for usny in the ciP. end it it | known that the latent period for other types of t.stour aasociaud with asbssto* ' expoftur- Is very long. Also it is not yet clear whether the excess bronchial care1nous r<u is always aeconcunlcd by ashestosis. This raltos the ; rsVlen of j how you define aaheetoei*. SuC`;octlono for an international agreement cr. dds J by a group of pulsonary pathologists have recently toon published (U.I.C.C., l-f$` t ' J 9 Vf l J ~I>"*~- --Hr ........ mrn'ini *J } trcs the U.f.A. (hancuoo^ Sa.i/of; ot oi, IJ&i) nay Inalcate that an excise aortallty froa iror.a'.ial c-irclr.aaa toy aiaft i,.*. asbestosis in tea* groups of s*beto-axpoe*d vorstrs. usance of The problca is at proront unsolved and suit aw^it farmer follow-up of the type pioneered b7 2r. Knox and Sr. Soli. We need eospartble studies ia other asboatod-oxyosed wor-ars, for we have to be .__ -r of ass-aing mat the fiahlr.-f m one part of the ino-stry apply to the wool* u;.ti. than we do at present. know such aore r: f a_t- r-crothrUal tuxourg I now propose to review briefly the evldaace ea the association betwe _a diffuse r.efiothcliwl tusours and exposure to ashosto*. The evidence on this subject le aecunulatlaj to rapidly th*.t ay coeaente nay be out of date by the tis* they are published. Hubert Wyera would have :een very Interested to lean that In retrospect one of the asst significant observations in his thesis was, and 1 quote (p.102), *sn endothellooa of the pleura le described In the present series, the first to be recorded in association with asteetosls ae far as the writer le aware". The picture of this ease In hie thesis shows the lung encased and tightly \t pTvssed by the surrounding tusour. The sinllerlty of ap;oeranee tu v.u flrut oaso rrpormd froa South Africa by Vsgr.er, Sieges, and Marchand (l$6o) Id ;*ara later Is stilling. Hubert W/ere wae sore than 10 yeere ahead of his tlhw Uiough we now know that eailler oaene ware in the records in the Pathology fiepartsente. (Or. Wagner has in the last J years collected as ooaplete a list ae possible of nil previous and recent oases of those tunours In the U.K., and this esse la Hubert Vyera's thesis is apparently not recorded elsewhere.) Xeoont discoveries in this branch of industrial pul&onary disease fend like 4' a detective story, and part of It rae been written elsewhere (Wagner. 19&A)* The observation which set off the recent research wee rede by Or. C* A. fileg,:*, working In large hospital in Klnberley. Around 195) be noticed that there were a nusuor of caeca of pleural effu-ioa In his beds which did not respond to aAtl-tuborculous chaooV.crapyj also, these cases case to his froa the West :ut rarely free me Last, although he we situated In the tlddle of the area he was serving. This led hia to think these cost be oda cases. A eu-.bor of than were trsnafenvd to Johannesburg where biopsy of the pleura was cade. o / jsw? -9Within a short poriod 16 cocos :io r-ecs cda^r.oi..- as diffuse sesoth^iial but information on the unuoriyir.g lung was not ev-iicble. Cn u.u wAsl* of an earlier -ingLe cote of emottncliol tumour whore a&boatoa tcaiss verc found ia the lunge, Vagner auggostod that asbestos tight ... rc.pocxible for theco other cases. This Initially aocaed very unlikely as their occupations did not fit. However, vory detailed industrial aad residential histories of the survivors and their relatives revealed that aaay of the paoplv ...d lived --r but not necessarily worked in the asbostos nines and tills In the I'crth Vest Cape, which is to the Vest of Klsberley. By 1959, at the tine of tha ."reuse- ooaiosls Conference in Johannesburg, an assooiation with asbestos had been >4-- o-i-J-* established in 32 of 35 <*mi. Later, surveys were Bade in other asbestos-producing areas in South Ifrloa to see if these oases occurred there also. ng.|J^shows the distribution of oas-t in South Africa to 2962. The majority of the cases have unown an association with the oroeldolite mining area, but there wore other cases freo industry where the exposures say have included ether types of asbestos. 2n tha Transvaal, where aaosJte nas teen mined since the *20s, no oases have yet . e.-a reported (Sluie Creaer, 1964a and 196<b); nor have any yet been reported from fiueslland where eioysoUlm is mined, though in appreciable amounts only clnoe shortly leferre the war. In Shabani in Southern Bhodeeia where there has also been a large ehrysetile sine for many yeerc, with a aedioal service sines the lata 19:0s, no oases of sasaothelinl tumours of the pleura have yet been reported (Walker, 1965) - The asbestos mining areas of South Africa are, of course, not places where Udinloelly satisfactory long-term epidemiological etudlee are possible 00 account of mobility of labour and look of records, but despite an intensive and maintained search over 5 year*, no oases have yet 5*rn discovered associated with the eroslte or ohryeotlle mining areas. Therefore, present erider.es for South African mining areas strongly sugwects that the type of fibre is an important factor la explaining the high incidence of diffuse aeaothellal tumours in the crucidollte mining area. In the United Klngdoa, up to 1962, no intensive search for oases had bsea maoc *.though a few cases were known (Vagner et al, 19*). It* the last v.rte yscre there hsvs been many .reports in tl.e U.X. (llourihaj.*, 1964| Entictaap o K" i  i . , "\ -10- u.-.c iaithor, 19&; Fouler et cl, l>bi; 0-i.r., l>vi; linos si el, 1$&y, Hinson, 1$65* end Steel and 00yd, 15t5)/Of groups of css:: largrij frsn _. pathological reccrss in racy cer.tr**, confirming tho assooteUon of diffuse assotheiiel tussurs of the pleura one poribor.ous anc exposure ~ aahostos. Tbs evidence ha* bta bacce either on astastos boc.es in the lung u,;/jr a bistory of contact with a. bestoa dust. ^ The records at The London Hospital started by tho lav. .'r. ..or S. X. A^ Turnbull and carried on by Professor Dorothy Russell and Professor 1. Doniech have provided the largest single {roup. Dr. S. O'E. Hourihane (I9C4) has analysed these oases bock to 1917 *nd Has shown a highly significant association between diffuse nesothslial tusours of the pleura and the presence of asbestos bodies in the lungs. The occupational and reaidcntial histories of these cases wors Investigated by Dr. Molly Xe-.fcouse (1965). Fig.\/. derived fros ber peper shews several li.wevasUng fillings. First, the equ^l sex ratio of the eases, quite unlike bronchial oarcir.oaai second, the increasing nuacer of eases recently. TiiiS is alsost certainly a real increase cf incidence as these tuvours have i.esn Indexed in the records of the Pathology Departsent ayths London fer to long. Thirdly, of the group found on a retrospective survey of residence ana eccupatiott to have had an association with asbestos dust, over a third (n out of 51) had contact with asbestos only outside industry, cither living near a factory r through dusty clothes, etc., brought hose froa work. Three control greu, - in this survey showed significantly low^exposure to asbestos and a difference in the area of residence. In tMs investigation nearly a third of the cases gave no history of rpocur* to aslsstos (though a proportion of this third had asbestos bodies in the lungs). There are nany possible explanations for this) it was a retro spective study so that information about sany of the oases was tlaoucr. In the sore scribes vherv the records have leca sore ccc.pl*te the association betw'fn tla tur.cura and exposure to asbestos has te*n even closer but, 0' course, ones a.t ascociaU.cn has bc*a desonstmtod cat rial collected in tils way cay be `-biassed, beoauae Individuals with a hiatory of working with asbeatos a-.d who develop syaptoas cuggesUve of pleural effuUon cay be referred to those with experience of these cases. iffvt' 1 -11- Thea* lr.vsti -tier.* in ruve rsi-lciy cor.fi.-cd the finair.c# In South ifricc of an association between acbestc* exposure and ciffuce urothelial t--w-ri. ~-.ay have shown thorn has ! ecu an important baserd, but it euat b* rcser.hcnd the average latent ;oriod fros first . ...osura to th* covelopaeap of the tucour Is about <0 years, and this cakes It very u.fficiit to assess the procrr.t hasard. They have as yet adaod little to t.e quantitative aasesscent of th* risk as between on* type of fibre and eantaar, on uc...-. of exposure* in coat cases. But taking th* whole picture they have cir.fi rued rativr than contradicted ths findings lu South ifrica. Vhre the proportion of chrysotlls used has probably been high, ths number of sasothellal tisours ess to b low, but this cay be partly due to difference* la past dustintss. Tha croup* collact* 4 in U.K. hava also eonfiraed^Vbat the: a tunours occur la the absence of aabesiosie la e*a2 cssaa. FiRyf**uar.ariae* for O.X. tba distribution of known easts up to!964, but th# pattern la ciiangiag as tha search la extended and intenaiflad. Tha association with tbr ports la la part related to tha u*a of tha taurlol for lac^isc In ship*. 2a othar oeuatrlaa tha association batwam diffusa aesothellal tuaours of ths plaur* and exposure to aabaatoa has bacn oonflmed. Za cany oasst tha datalla of exposure *r not known (Vandsr Sokoot, 195*3* Koenig, 1965* if<r IVrakal sad da Jager, 1961). Za Canada (Cartier, 195-) cad la U.S.A. A (Mancuso, 1963 and 1964) exposure was probably to ohrysotlle only, though details of occupational histories wera not available. Za othar laatenesa (Sslikoff at al, 1965) exposure to crooidolita was thought unlikely. Za Sorth* Vast Australia , easts associated with areoldollta exposure have been reported (Xettulty, i962i) Table sua/earisea tha nusbar of known tuaoura la South Africa, U.K., ad Korth Ar.erics at tha present. Th* rreent diseorarla* oonOeming the.* Uc.ours raise cany questions which oanr.ot yat be adequately answered - for exaapl# t 1- (1) Are asbestos bodies ooanonly prt.ient la ths lungs of th* general populatloat Th* answer Is ap;arently aore ornconly than coat people would have sua* p,tuJ a few years ago* In consecutive autopsies la ho*;i?als over age cf about tO, tha prevalence has varied froa about 5 to 53< (Ihaascn at al, 1363 and 196^i Kourlhene, I96ii Else* #t ai, 196^j Caur.a at al, 1965$ Heurcaa, J 'iiu te- v{:. &*.. - Vi t MM "MUff 19^5). -12The sethcda for eur<u. rav* varied so t;a; valid quantitative ecipari- on< between ong city or oao country and anothor are cot yot voric on this prcbloa it needed. Kore (2) Ans thr bodlos rcslly asbestos fcedio:? The pathologists secs ccr.relly agreed that tb*. --suer is protubly'yca in Boat instances* but there is aa urgent need for positive la*, r.tification of the type of fibres la * representative tcaple using x-ray dirfro. . sad other tsthod*. (3) Whet is the asdics! sigrlflc*no* of Asbestos bodies la the lungs la oeasecutlve Autopsies? The Answer is that nobody yet knows. They are evidence of poet exposure but whether the presence of sparse bodies in the lung oarrles with thri any Important excess aorbldlty or tonality, oaly future research will reveal. U) Vhst is the relation between pleura! plaque* and cesathcliol tusours? There are two aspects to this question. First, do eesoth.-ilal twaour# develop on the site of pleural plaques? Second, is there a high Incidence of Mtothelial tuauure vV.ere the incidence of plaques is high? The answer to the first part la tiiat occasionally it aay be difficult to differentiate histologi cally between the flbrotlo plaques and the fibre-eareon*.-like variety of the nesothellal tutour, but la general there la oo clear evidence of the plaques being a precursor of the tuaoura. evidence is conflicting on the second part. 2a Finland, cany plaques have beta report-d by Klvlluoto (1965) and also at post aortca (Meuman, I/65), but tiis inaidsnoe of cesothells! tusours is very low. Za South Africa plaques were coonoa la the survey of the population la the North Vest Cape where U.- seaothellal tuaoura Incidence was high, but plaques were also ecsson in the survey la the Transvaal area where ao eesothelial tusours have yet lecn reported (Sluls Crtner, 1965) (5) Za there an lapertant difference la the risk associated with different types of fibre for equal exposures? that steps are being nade to establish this quantitatively? The snewci fur* is that In South Africa a continuous search is being talatalr.ed to det'et a.iy oasts of ceeothslial tuaour coailng..frea the anoslts end ehrytotilc arc**} so fr non* has bson discovered (Si'll* fiitocr," jareotol co--runt 0adorr). In Canada a start lias 'coca cade to investigate systematically . Q P t-til w t! 7i IKl/il ' 'ST - .*' t5,i*-rr 11 : '?- t\i; and o*-v-er , roblc-3 sosceioted -.ih cnrycdtilw sining. Lot there art otter countlira in tkv world where * teareh right be valuable. Fcr i._e^le, la Cypruc, v!.*jv chr/satile cal;' hac ;cn cir.od tlr.ee das-leoi tines. Alto, perhaps Ccedhoslovakia where only Pu.s.--irn chryst.'.lo cv have ieea uted, and where r.o sosothslial tunours have !ecr. aiscovcrcd lr. eorvuyt f asbestos workers (Fschner, 19&5). The International Union against wr.ccr (U.I.C.C.) it helping in thle work following the report of Ita Working Farty or. .. uoa and Cancer la 19&4 A stall International cesnittee has teen established to oolp those with opportunities for contributing to any a.-ctt of this whole profit.-., to xeot and eo-ordinate that? investigations.* I la Flg^U I have atte.-ptab to show diagrsanaUeally a euorary of the health hatarde associated with asbestos related to tine and v rid productM of the slneral. This Indicates the long Interval betwrro the ev*rt of the industry and the recognition of astrctoifcf then an interval befor.- th.e excess bronchial carelnona risk was dtecud and only quite recently the discovery of a related hatard of thr pleural sr.d peritoneal tusours. Toe wry rapid expaniica cf the industry since tb* V&r is IsproeoAve sad w* aust rvneeber that the aesothellal tusours now being detect* d relate to output and condition* as they existed about J2 to <0 years ag. I Uvt sold saough to prove that this invaluable xinerul, for which there r* no substitutes for soxo of Its uses, has health hoiarts freater Visa were recognised at the ties Vyers was writing, or indeed when Sutherland was oo& trlbutlng on earlier lecture la this series (19&). X think Vyers wss wrong In his aanclu.loa about the effectiveness of legislative rea.'urea la eliminating asbestosls. He was right about the differ- aces In ths sffeet of the fibres, but pro; ably got acoelte and crocieoUts la ths wrong rdwr. He was a long va/ ahead of hli bias la drawing attention to ths osse of sncotheliosa. There are r.any d fflcult solsntlflc, aualatstratlvc, and technical problems ahead. Vs ar-' fortunate In this oountr/ In having perhaps cor* diversity of skilled people lnwrcswu In the a* estos problos than anyv.-.crs in the world, end who are Keen to pool their knowledge to salvo ths probl.a*. This was dear at the Xw lock Aeadcsy of Scle..c*s Symposium an 'The biological o r:t-*t*** tiii -----:....- . .---- j ~rrr=:.^r-~.'--V.V " *r. -14- of'cets of asbeatofi', held laa-. au'.vtr., ' . c-t ;.clf the cor.trituticr.c vara froc U.X. The '?roec^dingi1 of this S/mpoaiur., to bo pu-li.. i f.c*: sonth, cor.tain such at tho ovidcr.co bnofly roferreu to in thia lootur*. Thor* are cany othor aapecta of tho new w;r'. which I have i~ to ccit - for ouscplo, atudioa of lung function; eiassificaii-.-. cf V.o radiological appoarnncoa; and catboda of dust Mailing' I should like to and by recording tho oxeallont co-c>r.. . -r. wo have had frea Industry and tho Uniena in our retoareh in thia intore* ting, -.fficult, and iaporunt problos. Ho requoat for holp or Information has been r> Tho vlawa la thia locturo aro, of oourca, ay own, but I have bo**n greatly aati.ted by dlaeucaion with ay colloagwia *t tho Pnoucoecnioaia fteacarch Unit, and particularly Ur. J. C. VAgnerj so- boro of tho A'beatotis fatetrch Council; soabore of tho Pnouaoconioaio Panola of tha K.iniatry of Pensions a..d halloaal Insurance; and ranvoople in othor eour.triea with whea oontaet baa boon cade poaolblo through tho International Union against Cancer. ( o i > $ I "As1, -ft,-- - T c-rt 5v.:-`V- Ita Tic\ > rff. rr Alllkor. A,C., Karir.tar. J.S., fcirback K., *r.U ::a*h T, (l/o). / ' ProctJ.-dir.c of the iteond International Sy=>ot.... on InhAicd porticlaa tr.c Vapoura, Castries, 1965. U.-.dan, Parcosce . -. se, (? U publiahAd.) SMin W.p. (1955). ter., occup. iiyff. Z 14. Kuchar-an V.D. (1955). Prsceftdir.^* of the ,\'ev fork Ar-ao, -y of Scioaaao Syr.'oiixs on 'BIoIocIcaI ffcct* of Asbestos*, Raw fork, ly,,... Xaw York, Tha Xw fork Aoadtay of Saiaacas. Cartior P. (1952) Arch. induotr. Hye. , 262. (Contribution tt tha Discussion.) ' Cartier ?. (I960. International Congress on A*batoait (Cmb) 1964i Report and Ciscussicas. pS6. ' Caur.a D., Totten R.S., And Cress Paul. (1965) J. Astr. . Assoc. 19?. . Zevie J.H.C. (I960. Brit. J. trprrti. Path. ec. 634. Coll, Riohani. (1955). Srii. J. i&dustr. Xod. 2j>, 81. tlaea P.C., XcCaughay V.T.I., And Vada O.L. Brit. sad. J. 2* 353 (196$), Eatlekaop J.B. And finltber V.J. (i960. Brit. J laauctr. Ked. ?'. 23. Powlar P.B.8., S2o;ar J.C., and V'Amar Z.C. fi96<). Brit. nod. J. 2* 211* * PrFrwol X. a II. (1961). Orarimk QfdA jAArtoak ran KAflkarondaraoak a CAnkarbsatrljdlnc in h`d*r1ao4. tUrlneton J.S. (1962). Utura. 12L 4J. XArlr-cton J.S. And Boa F.J.C. (1965). Prooadin* of tha X*v fork Acsaany of Solanos* Confar'nec cn `lUoioficAl Lfracts of Akooatoa', la* fork, 19&. Xav fork, " fork Ac*drsy of Sciences. Handry K.W. (1965). Ibid. Blwaoo X.r.V, (1965). Brit. 5. U*. Cheat. 2,121. Holt P.F., Kills ond founc C.X. (1964). J. Path. XUct. 2# 15- Henri Una D. 0*8. (I964). Thorn*. 12,263- Xinluoto R. (I965). Freest dln.s of t a l.ow York Academy of Selor.oao Ccftf*r*-c> on `Molo^^eal Pffrct* of Aal uMi', .'< fork, 1964. Kiv fork, Tha Nam fork Acaueny of Sciences. Klostarkottar V. Person*! eosaualoatlen. Xr..:: l.T., tr.d Coll &.S. (19^5) . Proceedinj.* of Ua New York Ac*c.'cay of Seleneas ConCervr.ee on 'ilolot.lcel LCCecte of AoVaf-rto*, Kete fork, 1/04. New York, The ':w fork AcaUo.y of Scihncaa. Koa-vifi J. (I960). Arch. Cawarbapath. Cawrrbahyf. !, 159. fkr.c--'-o ?. T. And Coultar E.J. & C1C. (1963), -1- Arch, onvlrona. Hlth. (Chies^o), Srnrnmittu >**r.cuco 7. F. (196-s). Ferrer.-', cc.'."'--nic-tlcn. Sor'vr tl.cr F.P..A. arc. Pri c<- C.*..'. P.i^ort on the effucts of sc. j-to: cutter. the lur^t and dust -j-:-rr ssion In tv Asbestos Ir.custry. London, ii.?:.S.O. Xourv.n L. 0. (1965)* Personal contmniecti-n. "inctry of Pensions ar.d National Insuroacs, Report for ths year Iyc4. . Lor.Con, d.K.S.O. McNulty J. C. (19oD. Xcd. J. Auet. Use. 15. X* ,, XcVlttlo J. C. (19c5). Proccrdir.es of the Mew Yorx Actt,, f Selascss Conference rn 1 Pi ' <*xl Zfr'octs cf Ai'.cCLto', Hew for*, 1>64. Hew York, New York A esc coy of Sciences. Kscslschoidt C. (19o5). Ibid. Nswhouoe, Muriel L. and Ttwcon, Hilda* (19^5) 3rit. J. industr. Xed. , ' Owes, V. Clyn. (I964). Brit. cad. J. g, 214. Psdr.or P. (1965) Persons! cocr.unicatloa. ?rocv*.*inr.x-of--th* ,\'w-Tor* Acndrry of-Soie.-.csn-Co.. Ef:'ct* of Ac.aesUie*-,--Naw-for.?--19 *4 'cwYor.i-., ,`i Fo,>n J. M., Fee S., and Vslton W. H. (l/). Proceedings of t-.e Second Ir.vrr.nticrsl ;T.;,-.oiua on Innsied Particles and Vapours, Caabrid^e, I965. London, Psr^sson Press, (To V published.) Pbssiter C.E., River* 0., Jercsan (1S&9). Ibid. Caaowell C. ad Xa^elsehaldt 0. Sluis Crrcer C. K. (1945*)* Prccocdlr.;;* of the New York Aoada.ry of Sciences Ccnferer.ee on ,Ii.*.lo,*` -*' Effects of As. estoa', Haw York, 1964. New York, Net Yor*: Aoadeuy OS' Ccicnesa. Sluis Cf.-s.sr C. X. (19w5'). Personal eosnunlcaUoa. Sellkoff, Zrrir.iiJ., C;urj Jacob, and Ha&soad, . Cuyler. (U64). J. Anr. cad. Assoc. 22. Lellkoff, Jnrtr.,* J., Chur.-, Jacob, and Han-.ond, B. Cuyler. {'.965). New Incl. J. Med. , 56O. Sul P. J. and Boyd J. (1965). Brit. J. Ids. Chest. 1J3. Sutherland C. L. (I960). Trane. Asm*, industr. sad. Offrs. ^ 4, Thomson J. 0. (19*?). S. Afr. acd. J. 1^ 759. Thcrrrn J.C. {1965)* Pr; ca'din .* u` U10 .Vv Yor* Aoadesy of Sciences Co.-.fi' r<-.-.c* on 1 MwicMesl If.'.cts of Asbestos1, New for*, 1964. New '.or*, Hew Yor Aoaoacy of Scienoei. Tic'.rell V. (I965). Ibid. U.I.C.C. (IntnmsUcr.al U.iion Against Caneer). (1965). Brit. J. industr. Xed. ff. l6j. Vander S^hoot H. C. K. <1953) Hod. 7. uaneesk. 1C?. U25. P A Vi*lltnl I. C. and ?rr.;L L. (I'-:-/ of the .'.'aw Ycric Ae.'.^ir.jr of Science- Cor.f. r-r.cn or. 'licio. icel Aspacts of A*'r tc!', J.'cw York, lvJ-j. Now York, :;cw '.or*.' Ac-uej-y of bclc.'.cGb. Vainer J.C. (195?). Dia i.~yb. H, 56. WiTir J.C., Sice;.* C.I., and Xrch*r.a Paul. 3x11. J. Indvutr. Ked. XL r63* Va-zwrJ.C. (1962). N'-.tyr*. 196. 1?C. (i960). Vapr-r J.C. (19&4>. 1IV rnte.-rAticr.al Cco^ress on Cecu; *1 enol Health, Kadrld. X` r'rra co"ualcctd.or.a 106w/7. Vn;;r,cr f.C. (I965). Prococdinc* of tho J.'aw fori* Acodaay of Sciences Conf^rrlea cn 'Biolop'cal Ac-ecto cf AsYoctos1, Kav York, 1?64. Kaw York, N'cw Ycr* Aosdoa-/ of Sciences. Val*r if. (I965). Personal cocr.a.-.0*-!oa. V;-*rs K. (194o). A thesis ?r*ct.;tc4 to the University of Glasgow for tha dagr.'a of Doctor of .ladieir.a. 8*idl S.K., Kins E.J., Karri son C.V., ond Kacalsohaidt G. (1956). A.K A. Arch. insusir. Kith. IT. 122. ZZ Kor*?< T.C., Rot'art* V.H., Silvrrt.-n R.E., Skldnore J.V., and Vajnsr T.C. (196'}. Proceedings of th* So cone InVtMUwAl Sysprslua on Inhaled Partial** i--; Vt.ps-.irs, C*a>*r:c*, 1965* Lo.-.ccn, Parssaon Trsca. (f ba published.) " o it f * J ( Ift I A S BESTQS1S CASKS PIACNOSED l9S3.If63* ANALYSED HV PRINCIPAL QC-Cl'P \TIOX AND nATK OF I-.NTHY IN INDfST.-.V ' - 1933 1933-1950 1 9.'U- Total 1%) Opentng ) Disintegrating ) 3 35 3 41 {: 6 S) Insulating 6 Lugger* ^Sprayers Mattress 60ther* 41 1 2 3 31 8 1 9 22 11 102 (41) *J . Textile Carding ) Spinning ) 'Weaving ) 16 30 7 33 (2). 5) t> Slab and Pipe Making 3 15 2 20 (8) Brake lining 3 1 - 4 <1. 6) b Miscellaneous 10 17 - 27 247 4 M. P. N. I. Panel* London. Manchester. Newcastle. Sheffield. 6 Not in "Scheduled" Occupation*. (11) ramfltilBR I a>vi<. V K. Pinnnvjocnn.osus X.ui C...m>s Pi:u'r,.isi^ jnd> r the In.-^s: r..i i himr.rs Acl 1046 Type 19513 1960 1 9G ] 19C3 J 963 1964 Coal Mining By6Smos;s Asbestos;* Pottery 3523 3279 2768 2171 466 403 388 381 37 29 43 52 89 50 68 99 Foundry and Steel Dressing Slate Refractories Ouiioing. etc. Others 177 118 135 105 35 43 33 47 22 lf> 28 24 45 33 49 44 113 86 99 67 1215 334 271 67 83 76 65 no 95 38 69 24 13 42 48 63 60 Total 4507 4057 3611 2990 3042 1919 o e' * & :!li t i - .1 fc< C 62 V 2 a < > 63 r*s E S w 62 a 2 < C C < |M o 6} c/2 o CO 05 M d 3 U t> o cc < J3 (0 CO E o u 64 J aam m^&amwarn* HU m t o \ J' i o * ra .S O L V E D P R O B L E M S e p c5 E o u *5 c. V) o cj c. u w *k5* o c c E o CD eft o V 1 v* O Cft #'*A# c 3 ** `j <* Cfl V o X 0) 0 . V> cj "vi >* rt o u w o w 0 X a Cft X o u a eft +0* <" eft CJ 07 CJ ft X retft u- 0V &> o rt m* X) u w- CJ w C tuo o wc c t/J CJ *5 c a3 c CJ o r- ** V) eft cj rt Xo 3* CM c? Cft c 3 3 ii. s5 a c CJ CJ <* 9> U 3 ? * o CJ r* X3 C o -rt rt *5 *5 u CJ t5 X eft CJ 2g *> rt 3 03 rt * en CJ rtC u u "u 3 0 03 Sb* CJ 05 3. a CJ X o Cft rt rt Q. rct *3 X > 2 X fft* o ** rti s. 3 tft Q tfl 3 E h. r. CJ L. X wCJ W c. o w -K X i Cft CJ or 2 0 > rt u Cft Cj c 3 Cj C" X a >> 0 cj <** aL. c CJ u a* c CJ u e o X rto u o X c CJ u wCJ V- Wo. Wl 3 U * tifl C % a w0 X <S) A rc 0) DUST IN WAT LUM5- M tL C R A M M tS DUST ELIMINATION RAiES o-u <j---------- .& &--------S--------46 *5 551 DAYS A" t t / } i \ j- ' ' o tm+. \>\ vL Si s^ o'lB ` | .<D 3 o w I tt 5 s o 5? .O UESOTIIEUOMAS IN CUBA r BRITAIN 4 * I / <