Document 6wn46Dj43yDnbDQKmO5BREL9m

\V i i j **C ivlB UNION CA.HlVfDI.iJ OMITED . Hah i7 tffse *Alt$Q5--------- PRC:jmw HCKAI'TON STUKKT |,()\D()N W.l. MAY I A I II HIOO OAHl.US: l* N l \ fill l 1 Y. I.oSliDN \V. 1. - T li L t \ Dr. A.E. Pufahl, Assistant General Manager, Asbestos, Union Carbide Corporal. i.mi, Minin;.'; u: Me tal Hi. vis ion , 2?0 Park Avenue, New York, N.Y. 10017, IJ.3.A. 12th January, 1966. Dear Dr. Pufahl, You will recall that from time to time we have sent you extracts from publications which indicate concern felt in industry on the detrimental effect asbestos has on health. We tried to obtain some information for Southalls Paper Mills, who v;anted to use our asbestos in a sanitary tissue of the Internal type. The;/ wore concerned about, possible 11 anther to health. Wo vie re unsuccess I'u 1 th'ii i a oht.a i nine ansv;ers is.) tlielr specific i|ue:; l,i 1111:;, nml could mil.;/ (lea I. v/.i th them in v ry |/i icra I. terms. However, | feel l.li,al, W' may new lie able l.o be Hi' . J ' SJiecilie v/li'ii I,Ik- occasion arises by using the Information contaJ nod in the documents, Bri t:i sb Industrial Biological Research Association and Report of Proceedings of an International Conference on the Biological Effect of Asbestos, copies of which we enclose with this letter. We believe the documents are well worth having studied by the Medioal Adviser to the Corporation, and :it Is our belief that, we may well be able to take advantage of the fact that 0111' material sup]niseiII > contains so little of the dangerous trace elements that are mentioned in -those documents, it this is so, then we certainly have good copy for pub I i.o I. t.y use. You vii.'ll. bn interested to note that 'two Aineri.eni 1 medical aui.liorl tb s attended the International Conference, namel.y Du. II.K. Ayer, Public h'-aith ber/Jee, Cincinnati.!, and Dr. I.J. Gelikoff, Mount binui Hospital , New York. We would appreciate your comments and conclusions in due course. Sipyerely, A ' issa P.R. Cheston Assistant, Gales Manager c.c. Mr. II. Reichard.1 Mr. t TV in T rr_ 1 1 r -c ,/t .1 - 5H - A-C k*} K*'C C , -hat the silicone fluid is devoid of silica granule-s. [The intense fibrous tissue reaction and the . v. of . -hi;' refrastile crystal:; ir. the l-.-s Lena described by '..'.r.er g g* . , ' . u_g.) not been ron.-rb.d by other worh.r.-s using pure l.cu..; . .- . :: ilicuri'-r:. Tin. < 1 the 4.ree u.lir.nn,- nr.. ;c:ut. on.., r.:f.;rr. .; bp '..'.uer r r !. C1 r j o - e: i ;. ) c.-s I 7 ,.d Vegotasio butty .'ir..:.., '.1 v;'.,.;:l nr.'I of .n.boring dr. their our. right th.O .;ov...e reaction observe.!. It is .guito probable that a significant cr -. .-. :.u. jir role was played by the fatty acids ir. the induction of the reported severe fibrous iesicr.s. If wo are to believe the ciair.t of the cuaster.se of silica granules in the salioor.e fluid preparation, then it is conceivable that the silica nay have beer, a contributory factor in the prcduovLsr. of the tissue reaction. however, a very reliable ssttrcc of ours has. r.o hesitation in refuting the claim that silicone fluid is cor.tar.ir.ateu with silica. Only under conditions of extremely high temperatures and high, pressures and in the presence of oxygen is oxidation of silicone fluid to silica possible. For this reaction to proceed during shelf storage is r.ot only highly improbable but wcll-nig.-i impossible.] :: a o y ; g g : c a a :: d a 2 b z ? 0 s The development of tumours (mesothelioma) following exposure to asbestos dust tends to be insidious (5IBF.A Bull. 1555, , The tr.itiai obstacle to recognition of oho hazard lay ir. correlating two episodes -- exposure to asbestos dust, however light, and subs.: stunt ic-velapnent of the tumour. Once this connexion itud beer, ustabi.r.h.cc th.c problem. assumed now und so.mowi.at alarm_ng dimensions str.ee the time-lag toewe cr. cause and effect map- -./ell extend to over half a century. IcfGrc ;550 the industrial and corr.ercial importance of asbestos ir. this country was still relatively small. Thus it is only r.ov that the incidence of diffuse pleural or peritoneal mesothelioma can be expected to show a steady upward trend. This pattern is becoming all too apparent. Public interest in -the p.-oblea should cert^-.rviy have hem alertcu by a report an the r.ur.dny ?lr.:.;s (>' October Ts'j i) on tiv.- w.rh ,u..o (lie. .1. isd. Mod. , 1.7, I'M). Vi..:..; n:.p .rt.s.t ..p, logical utuay cw/c.-;; M-i pa (ii .'-.Ir.; .-.r.i: 7,2 ...Los) v. ts ;.<...iti.v<siy .ttairne.erd di.flua rdciuai. or ritonoal :...nOt;V;lfnsi t l.s! t i.'j.ntiou Houjut.il over tin: co'..r.:c of approx imatoly `jCj yr. l.'.er-;..1 exposure to ashes ton ..as Gut. lined in 40 of the 75 eases whose b..c!;.grour.d histories could bo traced with relative accuracy. Cf the remaining ;,6, 11 had lived within half a mile of an asbestos factory. In a control group of 76 in-patients, matched for-sex and age, only 14 gave histories of previous airoct or domiciliary exposure to asbestos. She rioc in reported cases of asbestos bodies ir. the lungreflect either an absolute increase in incidence or the results of more searching pathological examinations in the light of this r.ov ir.ovlcdge. Be that as it may, Cauna et al. (u. /a. med. Ass. 1965, 1571) report a 41/' incidence of asbestos bodies seen in tho course of ICO routine adult autopsies (47> in stales; 547^ in females), although r.ono were founu beforo tho ago of 24. Mo casos of nosotholioma or asbostosis coals, be identifiod and primary cancor of tho lung was only present in two patients -- ono with asbestos bodies .und ono without. Tho authors draw attention to AM 8 GC / 515 the problem of positive identification of the asbestos body end the differentiation between it and the similar structure encountered in talcosis. They believe that the problem is made more difficult because cf the cirdlarity between asbectccis arising from exposure to trcr.olite and talcosis. HisiDchcnic.nl differentiation is thought to be necessary, but the method us"! in the present study van electron-probe .analyaas. "sr.ethelerr., the muth'vs refer'-''! findings which did not j.ouitiv'G y i<!<.;!!. fy elasr. 1 cal ion bodies and still prcbs'-c! isoj/h see --:ch nr-v ions studios had revealed at autopsy, : Vf>. si Cape Vova (lla-mon '"t -.1. S. f.fr. red. J. 1?r,jr yy/yy) aud in Miami (Inonron, Conic :".r.ce on Biological affects cf Asbestos, Hew "orb, October 1?o). French verhers have also dravn attention to the problem, and an analysis of hi s t epatho 1 ogi ca1 findings has boon published (furiaf ct al. Ibressc rod. Tj), 215?)- Although the asbestos industry in flint ccur.tr;' is net large,- the incidence of mesothelioma is rising and concern is 'understandable. P.eccrdir.g the incidence of asbestosis and mesothelioma and standardising diagnostic techniques formed part of the terms of reference of the Vsrhi : Group convened, under the aucpicec of the Geographical Pathology Committee of the International brnio:i against Cancer (I.TJ.C.C.), to lock into thy vhel'1 question of asbestos and cancer. The eompr'diensive report of the Group (Mr. J. ind. Med. 1955, 2?, 165) rece-m.'-nds three main-lines cf ni'T.c!:: Mpidor.iologicai -- more information is required concerning the results of exposure to particular types of asbestos fibre (amosite, crocidelite, anthophyilito, cltrysotile or trcnolito) by inter- and ir.trsnntior.nl studies in specified areas. It is recommended that studies be undertaken into the relation betveer. dust dosage, the physical ctr.ce of the dust and the incidence cf acbectosis, carcinoma, mesothelioma and other tumours. It is aloe proposed to vidcr. the field of enquiry to embrace ancillary occupations, ouch as transport, clocks, building etc., which ray involve lees ir.tonciv'' aeporuro to ~o ~. -Ml - ----- - ' ''' - M:"' ''.'or. should be ri porously sorecr.'"'. to eicr'vvrc to asiir-.etos rii'.st. Pathologj eal -- it war. felt necessary to st.end.ardi re criteria <vdiagnosis under the careful s'lperv Is lor. of a 'on.sull at i w j-ur:i. of p.at.holrg:'si. A a onduaveur will Me made to grade the d'gr"'' of re;'rosary fibrosis due to the :uor>-nce of asbestos rr.d routine e.ras.ir.'.ticr. of sputum, fresh lung or fired t i c s v "r. (,sh.err> available) for s.sce-"cr '.''''os or fibres will be incorporated into all pathological era- ir.aticr c. Fh;-~isnl an . chemical -- the possibility vas discussed cf csss.Viirh.ing a centr" to prcd'.'.ee a set of analytical standards and to investigate the biological, physical and chemical characteristics of various types of asbestos fibre. Methods of identification of the different typer of fibre in large samples of tissue and in lung sections were also discussed. Investigations a.t the Pneumoconiosis Research t7r.it, Llandcugh Hospital, South Vales, vcrc designed to resolve the suggested association between exposure to crocidolite dust and diffuse pleural mesothelioma occurring without intervening asbestosis, and between asbestosis and subsequent lung carcinoma (Vagner, Bull. Un. int. Conor. 1955, j> (2), a i use i  } - 516 - 2). The following mechanism could provide a possible explanation: Heavy exposure to asbestos -> Prank asb-.-stonio --------- > Pulmonary cnrcincm. light exposure (especially to crocidslito) Ho fibrosis, out -> asbestos bouios or fibres J11 ffa.; 0 :.; s o *. he 1 i e c.. '.'t r.icurs. or ~r.is pattern vou_d j: tar to e:ep_air. previous reports 01 _ow inoider.ee of naocthalicmm, especially vhero pathologists only considered the existence of this particular tur.our ir. those oases shoving fraud-: asbestoses. The study of Hcvhouse i Thompson (loo -cit ) revealed that in 47 ease:; from th.e group showing positive mesothelioma, whore tissue frer. biopsy er necropsy or sputtee could be obtained for examination, 10 (62. y/j) shseed evidence of either asbestos bodies or asbestosis; but ...0 an.ferity of those .shoving- frank .asbestos L:. were vork.jrs actively ( r..1 or. ,, addin.; raw :aa: \ theroiero in to m,:.i i;or.t.i over long- periods. It was also shea' that the heavaer and longer th.e r exposure, the shorter was tho interval before the onset of symptoms ar.d 'the tir.e of death. Obviously, therefore, tho denser of incipient r.os'itholiota, is present, ao.on,; those who are exposed throu.;h. contact with a relative or who live m the vicinity of a factoiy and are thus suspense: to only minimal exposure. Suspicion has been focuoscd on crocidolito as tho causative agent in mesothelioma, but in cost British factories a mixture of crocidolito, the atr.osphere an; cr any ci the various constituents of the dust. Studies cr. ho organic c.cr.scner.to oestos are oemg carrii out oar mgs on et Cancar Canp.n 1964, Mo.42, p.25). Two fractions cf oig___ ; .-.-atcriai cm be determined: oils present naturally and oils arising frer. centcminaticn during the munufacsure or transport of asbestos. Bxtraated sa.trles cf a particular batch cf ar.osito v/h.ich had previously appeared to be :.;n- curcinogenic, or only wed-.ly so (V.'ngr.or, Mature, bond, `.'jol, f;, ' . d ,, have seen found to be assn w.nte't with the development cf r..e-;.- in -narnter:: (hulikoff, commun station in 1 to Iin run . (Ijpp:. i_; - ) . A ::.i.::p!e* of :.i.* o e, ;.in: o 1`.ru-. t. ls :iow he1::.,; i. :.c.r,i-;tl !y :.o r.t'.:; as ;.ae'. of a Lot..test. Utnes y-.s .!. ;.v mcluhes investigation of tnc possible tu__. ..--ini tiatir..: ,ic L. vu ty .-.f crocidolite and ai..or. Lto oil in conjunction with the protoui:..; n.v-.at erotcr. oil (3IBBA Bull. 1962, 1_ ('), -j'l). bc-en shown that a storago poriod of 6 .tenths asbestos ._rbs 70-2^ of tho jute oil present in jute sacks (iiarington, Trans. H.Y. Acad. 3ci. 195; In press). One sample of extracted jute oil was shown to have tumour-promo tm.g activity when a known carcinogenic polycyclic hydrocarbon was used as initiator. V/agr.er (loc.cit.) also reports on the relevance of the presence in asbestos of aromatic polycyclic hydrocarbons, including 5,4-bonnopyrer.e. Bo hydrocarbons -have been isolated from chrysotile (the moss widely used type of asbestos), but crocidolite, which was mined in that area of South Africa with a high incidence of mesothelioma (Vagner et al. 3r. J. ir.d. Med. i960, 1_> 260), contained 3i4-6en3opyrcne in relatively high amounts. The suggestion has also been made that asbestos carcinogenicity nay be related to the metals or metal complexes contained in asbestos fibres; chrysotile contains nickel (0.?/j) and chromium (O.IJw), visile amosito has nangunoso (0.7?*)- Serum can eluto small amounts of nickel, chromium, manganoso and magnesium from chrysotile, and iron and manganese from A 11662 A i '\ crocidolite and ar.osite (Harir.gton et_al. Icc.cit.). Pleural rocsothelicras, similar to those found in hunan cases, can ee este.blished by intraperitonc.ni injection of asbestos into haunters (faith Bloasser, Jodn Broc. Join An. Socs crop. Biol. 1565, BA, 550). There in a great ooaoo of urconey in tho search far a so She eu -ro')'. e-- of p c l.fo 1 cry of roaotholiTn. Aoll".l- ion. to s's:-'.ion "`'a jyLri; silierri: ns: Ttoair respectively, but silics. is r.tr-rrc::.::;':.-.; except vs.en introduced Into specific sites such as tho pleural cavity of experimental aniralr.. The effect of silica and asbestos cr. lyso.tcr.es and Chacoecr.cs (phagocytic vacuoles) in macrophages is being studied by inrington A Alliscn (Hep. Br. -top. Cancer Caron 1964, Ho..'.2, ?.24). When tsi;on v.", by the phagocytes, inert materials have negligible effect cr. the ,.i....-.........i -.o t ...,0,.,,n- :yy oo (sn't procurably asbnslrs) cure: .................... \ . . . I .....................! ' . I i < I f I i o . . ,* i:.n O .. . . ,-..t - 1 ' y < .' ; * . r 1,. . * i ,1 f ' t !.`f f. ' ........ ............. ' 1 o . 1 o .: * i 11 - v ' 1 I ' I ri o [it { 11 I i 0 .* ; | | 1 ' S . . ! ( ' > j , f ) A..C-iybi_ Jii.ii, u L; t,: I;/, cull .iciili nmt J': i. t'tus nciiou can be neutralised by poiyvinylpyridine-H-oxidc vhich is. taken up by phagoscrcs and lysosor.es and apparently binds directly vita the silica surface, preventing its toxic effect. Asbestos studies cr. sir.ilar. Iine3 s.ro r.o-v in pregreas. ::'ivo-/o-1 .-lvs.rone-.s. of t!ie problem and w li 1 irgmia, to tackle : t car.not cor.pletoly -.ink the mV-T inf; thought ir.pl ici t ,'n this ciiot.a'.icn from the rnprrt of hoc '.kirk.:f-roup (loc.eit.): "........... further e-ases of these associated tur.ov.rs : re o::t*c of. .; for rany years to core, even if dust exposures arc r.ov greo.tly r. Bust exposures a.re an fact increasing, for the probler. is r.ot cr.ly confined to workers : n tee asbestos and contiguous industries. It concerns all of us who have asbestos boards in our ccilir.es and vails, .asbestos rats on our iro.oir.g- boards or asbestos installations .around the water pipes. Iltimtcly, sore font of control over the manufacture, distribution ar.d i:se cf asbestos products is to bo expected, but 'until such tar.c. the prognosis of reootholiern indicates tho need for restraint ar.d. care in the handling and use of this potentially dangerous substance.