Document z79OdRNjKgB3Xroon23wwYo6

s m n i ? o f, /, !* Oits HiJ Vul. k, ff i' t< hH LlJ, IM'. ClUl IfiUift -'3k'lim<e. (/ocj PLAINTIFFS | EXHIBIT 1 30W-277 SOME OBSERVATIONS ON ASBESTOSIS G. I- Uathart and J. T. Sandcrson Dept, of Industrial Health, King's College, Newsraxtk-upon-Tyne Ahstraet- Asbestos*, which is a fatal occupational disease is still occurring JO yr after steps were taken to eliminate the disease. This is because of espansion of the industry, and especially of cf<c insulating uses of asbestos. Nearly half the certified cases in the last two yean rccurrcd in insulators, whose work is not covered by the regulations introduced 30 yr ago. The work of a laggcr in a building is described and it is concluded that mixing of mag* ncsia.'asbcstos plaster is the chief hazard. It is supecstcd that efforts should be made to find, and use. a substitute for asbestos fibre and that distribution of rcady*mised plaster should be considered. In the meantime the Asbestos Industry Regulations and the Silicosis and Asbcstosit (Medical Arrange* ments) Scheme should be expanded to include the laggcr and his work. ._ Until such steps arc taken this essentially preventable disease. i)lcoaUwJ$ unnecessary death and suffering. *' * INTRODUCTION Axrkstosis is a fatal disease. It is due to a spreading fibrosis which not only restricts the expansion of the lungs but also interferes with uptake of oxygen into the blood. Kventunify it causes death by slow suffocation. In a minority of patients a fatal cancer of the lung develops, and we seem to have been seeing this termination more frequently in recent years. The disease was first reported by Auribault, (1906) who ascribed to this cause the deaths of sixteen workers in an asbestos textile mill between 1890 and 189S the first British case being that of Murray. (1907). By 1934 Wood and Gloyne were able to report their experience of 100 cases, mainly derived from the textile milts, in this country. Following the report of MtREWiTtira and Pricy. (1930) legislation was introduced to protect the health of workers handling asbestos but this took a few years to become effective. This disease takes, on average, 20 yr to become manifest but if the measures taken In 1931-35 were fully effective, there should by now, some Xyr later, ben* new cases occurring. In fact it has bcenmy experience that the disease b * increasingly frequently and the object of this paper is to examine this possibility and to describe the changing pattern of incidence of the disease. ; v*a CERTIFICATIONS Figure 1 taken from Liatiiart, (1962) shows that certifications of asbestosis have not shown a satisfactory fall in recent years and that they may even be incteaa* tog. Like all certification figures they must be interpreted cautiously as there may %vll have been changes in diagnostic accuracy during these 30 yr: and there have keen alterations of the law, especially the Pneumoconiosis and Bvssinoxis Benefit Scheme of I9S2. which have brought more men into the compensation scheme. s as DOW 06083 G. L Uatiurt end J. T. Samwrjdn S TOO I ? 0 '|5 1952-59 42 cun certified under the Pneumoconiosis end Bysrinoals Benefit Scheme hev been edded to the normel certifiestk m 04, 7 per peer). Moreover theasbestosindustry has expanded greatly during this period and there probably are moremen exposed than there used to be. ' THE ASBESTOS INDUSTRY In 1935 the asbestos Industry employed 10,000 workers; In 19SS there were 18,700 employees. Expansion ofthe industry Is also reflected In Increasing imports of asbestos, recorded in the annual reports of the Board of Trade, which are repce* tented graphically in Fig. 2. Most of the cases of asbestosis which are occurring nowadays started work in the industry before 1945. The further expansion of the industry sinee that date suggests that we may see many more cases in the future. Tam I. Amnros moouers m rm cure xmocow (row)* 19)0 IDS 1958 Bf # AAaWStM ielTHm pVwVHI 2. Peckinf. lafginf, end jointing S. Brake and dutch liningt 4. Other attestoi products () 5. Aahettoa tntiWi (b) i. lowletinf materials (t) 103,720 I4M00 - 411,700 3070 . 720.,, 42J00- 220.'\ IRfiOO* 22J74 22,117 0 1*4)4 MjOOfi (a) Mainly attestot testdes (4) Eadudlftf these contained in 3 (t) Included under 2 * Appredmeie < ! ** ! 1:1 f eve r< tie is: F: a i i i, It s: re cl t oow 06084 Seme OV^rv jtiont on Asbcstosi* wnnt vom u 47 s T n o | 201,6 Fto. 2. Asbestos imports (tons) of the United Kingdom 1915-1957 The first cases of asbcstosis were derived from asbestos textile mills, but analysis cf the asbestos industry (based on the Board of Trade Censuses of Production) <.: rests that asbestos textiles have increased less than some other products (Table I). 1*. :> unfortunate that information given by the censuses is not very detailed. How* e rr. it appears that the greatest actual increase has been in asbestos cement ;:oducts, but the greatest percentage increase has been ill insulating materials,* *hich increased six*fotd by weight, between 1935 and 1958, CERTIFICATIONS IN DIFFERENT JOBS Unhappily, growth of the insulating industry is also reflected in recent ccrtifica- 2t:? t of eases of asbestosis. The eases certified in I960 and 1961 have been divided i-' -o groups derived from different occupations and are represented pictoriatly in f 3*. It can be seen that 32 out of the 67 eases were employed on insulating or s'brstos spraying. The Asbcstosis (Medical Arrangements) Scheme of 1931 is concerned with - rdicat supervision of workers in textile mills and asbestos product factories it it disturbing to find that in recent years the majority of eases of asbestosis been occurring in the insulating industry which this Scheme does not cover. Moreover it is quite likely that regular medical supervision of insulators would eal more cases than are at present coming to light through hospitals and chest e':aics. * 1 am indented to Da. 1. WAtaix*.piTCHioau, of tha MinUiry of Pendon* and Sf 'u k*vrinct, for the certification figures. DOW 06085 L h, 0 Z I C 0 1 S C. L. Li atiiaht and J. T. Savoi xso* The inciitvncc of nxhe'tosis among insulators is unknown. The total number i f men employed is certainly less than the 18,700 in the asbestos products industry anj probably is about 5000. In this part of the country rather fewer than 500 n>cn arc lHA. UKS'sS *AWCt IICV unties MUM MCfOrr ASHOOS VNiMC ntiMc MMtacss mum Fie. 5. Cases of asbestosis certified during 1960 and 1961 grouped according to occupation. t ' s- 1* f *.*'tv * *^' '*rT~s-, WrfWfW engaged on this work, but 1 have'personally^seiOT8!,'fcaseotlasbestosisifrfm^^ amongst them. It therefore appears that asbestosis is relatively common in insulators. ' In view of this it would seem justifiable to take a closer look at the insulating industry to see if steps can be taken to reduce the prevalence of asbestosis. THE WORK OF AN INSULATOR Insulators work in ships, power stations, factories and buildings, where they jrc required to lag boiters and pipes. The material most commonly used for this i* a plaster consisting of 85 per cent magnesia bonded with 15 per cent of amcsite asbestos. It is used in the form of pipe-sections, slabs, and powder. Valves and flange are covered with asbestos mattresses (containing the same powder) and occasionally pure asbesto sections (bonded with sodium silicate) may be used. The tagger fastens slabs or preformed sections round the boiler or pipe with wire, then applic* a coat of wet plaster by hand, and finishes olT with a coat of waterproof cement On board ship, where temperatures are higher, the pipe sections are finished off with a covering of asbestos cloth made from chrysolite asbestos. The installation of a new heating system in a local hospital gave us the chance to watch the work In progress and to make a few measurements of dust conccntution. The workers say that the mixing of powdered magnesia/asbestos plaster with water, and the stripping ofT of old larging, are the dustiest processes. Mixing < done in a bucket, dust bin. or large box. depending on the amount required, and illustrated in Fig. 4. The mixing process takes 5-13 min and is repeated every 2-4 hf Usually the mixing is all done by one person, often by the apprentice who has ju*t started work. Knowing that asbestosis is slow to develop one might suggest that it would be better if this dusty work were to be done by the elderly worker ncari*? retirement. Often the work has to be done in confined space*, such ax between bulkhead' a ship, or in long ducts beneath the floor of a factory. Figure S shows a "Inf?'" DOW O 'lO ^ IU O lS Fto. 4. Air umpling by thermal precipitator during the mining of magnciia asbe*to platter ith tcr. ru Dow ^6087 G 'lO i I 0 0 1 70 C. I. t.t mmaht and J. T. Samhon medical examination by a member of The Pneumoconiosis MedLaI Panel, and tn.. power* the medical specialist to prohibit the employee from further work in conta.t with asbestos. In practice this scheme means examination at intervals not exceeding two years and the examination frequently, but not invariably, includes a chest radio, graph. Men working in the insulating industry are not included within this sclu-n.e and, as things arc at present arranged, the tagger is denied the benefits of cm ironmental precautions at work and of periodic medical examination, but entitled to "compensation" when crippled by asbestosiv It would be unfair to the industry to omit to mention that some of the larger firms have a voluntary scheme for periodic medical examination which is entirely free to their employees. Such schemes arc costly and tend to be ineffective because they are voluntary, and because the employees fear examination may lead to suspension from work. Now that so man) of the certified cases of the disease are occurring in taggers it would appear that step, should be taken to make such examinations a legal obligation by broadening the Medical Arrangements Scheme*; and the preventive ideals of the Asbestos IndustryRegulations should al>o be applied to lagging. PREVENTION OF ASBESTOSIS.1N rr ^frm The principles upon w hich the prevention oCd automation, total enclosure, exhaust ventilation.' respirators. fare^weH*khwrn (McLalgw.in, 1953) but few of them can be applied to the job of the larger. Substitution of an innocuous material for asbestos would seem to ofTer the best solution, and, in fact, artificial rock wool and glass wool arc being used in increasing amounts. Both arc believed to be harmless to the lungs but our experience of them is not very extensive. Unless it is bonded with resin, glass wool is unpleasant to wetk with. The workers complain, not only of itching skin, but also of a "burning" sore throat and this suggests that bronchitis might be a late sequela. Total enclosure is obviously impossible but the mixing of magnesia/asbestos plaster with water might be done centrally, and automatically. The objections to this are financial and based on the costs of distribution of ready*mixed plaster but since the plaster does not set (as cement does) and can be used days or weeks after mixing, delivery of a plaster slurry in bulk might be considered. Another possibility that might be considered is to make the plaster sticky before delivery, perhaps by the addition of a water soluble oil. Exhaust ventilation is clearly impracticable but forced ventilation of confined spaces on board ship should lower the dust concentration. Personal protectiot of the worker, In the form of some sort ofdust mask is theoretically feasible but it must be remembered that lagging, like ail plastering, is heavy work for which the worker needs to breathe ten or fifteen*thouxand litres of air in a shiri.Thc dust filter mu'* be capable of passing such a large volume of air without becoming clogged. Facemasks are often found to be too hot for comfort and this objection carries particular weight in the case of the tagger. Ills working conditions are hot and humid a* the pipes on which he is putting wet plaster are usually hot at the time (in order to dry After prevention of fin's paper the author was informal that the T.U.C. aod the Min*'** concerned are at prevent engated in dteussions on how tn achieve this. ct n ao. A h d b r w a ti d A ti it ti DOW 06088 I ( Some Ob*cTYi 71 cut the plaster) and we hast recorded corrected effective temperatures as high as 89 *F (Table 2). Tatu 2. 1)anok or conucrto'imcrm tnmu> wets sxneiiNcto dvmno asatstoa laocinq m a MMmAL * Working area Cometod efforthe temperature. *F aoraml scale Lara* hotter plant I2ftxt)ftx lift Large duct 10 fix 10 ft Medium duct 7ftxft Small duct SftxSIt v * NVaZEmK' *< * IS -4 & It therefore seems unlikely that the dust masks will be worn conscientiously and' the provision of dust masks is probably not an effective preventive measure; More radicat steps will have to be taken. . .. . .. CONCLUSIONS:.. v `. ' ' y : ' It is dear that asbeslosis is occurring among workersin thesinselatinf:industry .` and it is felt that steps should be taken to deal with this problem. Closer supervision^ of the taggers* health, perhaps by extension of tho SiUcosk aixLAsbestosis (Medical` . Arrangements) Scheme, should help to focus the attention of employers:on this. :-r, hazard, and to define the extent of the problem. Preventionof the: disease probably depends on substitution of an innocuous material for asbestos but something might*" o' 1 - be achieved by reducing the handling of dry asbestos plaster. The provision of respirators is less likely to be effective, because the hot and humid, conditions in which a lagger works add materially to the discomforts of wearing a respirator. The object of this communication is to reveal thehazards of the lagger*s workto wider audience in the hope that something farther will be done,both by the Indus*--, try and by the Health Services, to prevent him devetoping'a'erippllng.and fetal , , disease. * ' ** . : Atk*e+lt1irmenit--\ am fratahit te Mrs. D. Whqntmam far drawing Pit*, t, 2,2 and S, and to tteDrpartmcfflofPhototraphylnthf Unk-rsltyofDurhamforFlffc4and3. AadI am mpacialbr indebted to Da. J. Watkrm*PncHioao for the help given by Ms Department and for the informa* ties uted in tha construction of Figs. I and 3. REFERENCES AcaitAUtT. M. (ISOS) Ml. htp. TVtrr, (|4th year* Farts, p. 120-1)2. Meant, H. M.(IW) Htfwt of Deptrimenttl Ctmmtttrt m Ctmptnutlmfi* fttJuurkil Oisrmtrt. *f Fti,h nte. Cd. 3496 II.M.S.O. (Lon.), p. 127-121, - .mJ1 tamrtU. IJSJ. oo O O O <-0 O DOW 06089 sT00 I 205 I 72 C. t. Lf ATMAftT ind J. T.Samxuon Mim^ai mia. F.. R. A. and Putt. C. W. (t930)'JBprr x Efrm of A<hntot Dmu m tkf /,,, , ami Dmtt in thr Atbextat ImdaUff. Home Office. II.M.S.O. (l.cmd.). Lr atm viT, O. L. <19f2) SraJirt of I'vUiwaary- fkwetiom t* Warkm txpotfd to Atbruoi M [> Thcxiv Camh. L'niv. McLaiv.iii in. a. I. G. (IW). (Mitret it, 41 and 104. DISCUSSION Dn. F. P. Gai t (Siebe Gorman. Chcxsington, Surrey): What about the possibility am) . tijp* of wearing a dust mask during the mixing of the asbestos platter whkh take* abuut t.> minutes of time? Dn. D. E. lltCKtMt (Occupational Hygiene Service, Skxigh): 1 would like to thank you for >,- interesting paper. During recent yean our Dr. Chalien looked into this problem and w* a% < concluded that mixing and (tripping were the haardosn procenc* though we did not hate :!< opportunity to do dui count*. We did notice however, that even when mixing was done in it.-, open air it is often done in the bottom of an oM oil drum and thh meant that the man doing i: j mixing is bending down with his head in the dust cloud Inside the drum. The point that I wov.' like to make it that we were shown figures of dust counts of up to 300 partklesfent*. It b my o* a view' that the M A C. of 175 applies to particulate dust and that a figure of 30 partkles/cm* ou') be more realittk for fibrous partkks. This would make the taggers work more dangerous th Dr. Lcathart hat implied. Ma. S. G. Lvxo* (H M. Factory Inspectorate): There is a legal reoulrcmcnlto taka alt step* protect these people and I hope to enlighten you when I speak because this may help. Da. J. S. McLtviocv, vc.a.: Normally when an industrial pulmonary disease is jccompaniej by a typical radiological appearance, this X-ray picture b taken as a major criterion in diagnose and I think Dr. Leachart implied that this was the case in asbestosis. But f understand that asbestosis may now be diagnosed for compensation before any X-ray changes can be seen. \\W4 Dr. Lcathart care to comment? Is it possible that this may be one of the reasons for the revir rise in "certification'' figures? Ms. F. B. CaottUY (t.M.t. (Kynoch) Ltd.): Would the pankte sire range 3-S0p use) iDr. Lcathart'* experiments be within the respirable range? Faor. R, F. Law (Manchester University): Since it has been implied that mixing ashe^x plaster with water is the cause of asbestosis it is very important to know how much time is vv: on this process. Can 1 ask how long the mixing process takes and how frequently it b done durrrg the shift? Da. SvitHtas (Cape Asbestos Company): Dr. Leathart's excellent paper reminds me that < have had previous occasions on whkh to differ a little. Firstly t am not as gloomy as he on iN question of incidence. The regulations promulgated in 1931 came into foree in 1933. The I";' incidence of the later thirties reflected the working conditions of the pre-1933 yean. There v a. s< he has shown, a drop in the number of new cases in the late forties and early fifties whkh refleve l the improsed conditions after 1933. The rise in incidence in the latter half of the fifties reflects t*< war-time working conditions when more people were employed on increased production at a ti** when black-out and security were more vital than ventilation. A study of the number of yean esposure before diagnosis in a series of eases gives a trwr pkture of progress, tn the scries reported by the late Dr. Wyers, up to 1949 the avenge exposure** bis cases was 10-S yean. In a series of cases from the same factory, ftilly investigated at Hamne** smith Hospital In 1959, the avenge exposure was 14-S yean. Thus in 10 yean the improvemn was already evident. (Table I.) On the question of incidence of malignancy our experience differs from Dr. Lcathart'* 1?* pkture In this country Is also very different from that seen in South Afrka. where I recently some most interesting material. Then one saw many more easos of pleural involvement and piec'd malignancy. The South Africans find our incidence of what we may call parenchymatous ma':* nancy quite astounding. Similarly the South Afrkan experience of peritoneal malignancy di*<7i from ours. This will be the subject of a subsequent communication. These variations in man's reactions to asbestos stimulated me to consider the differences bet***'1 various types of asbestos. There are three main types of commercially important asbestos. Th'* re chrysolite, crmidotiic and amnsite, the two latter are gmuped as "amphihote" asbestos. T` ` differ in geological formation. In chemkal composition, in cryxtalinc form, in fibre xi/c ' * inspect, in their effect on man. I have tabulated a few of their differences and the result is interest'* ? (I" ' * I | i , DOU 06090 i Some ObvfnatioM on A*bcMo*i r\ t i r i 06091 74 O. L. bMKUt llkl J. T. XtMMMKN Consideration of ihe sariatiom between types of asbestos may well lead to a better am.'-.:. tarKtioe of the nature of its tffMi on man. I feel it K no longer enough to report that a man been <\po. J to asbestos. We mint determine with which type or mature of types of asbestos. man has worked. Poor. R. C. Baowst: Can anbody in the audience tell ut why asbestos H carcinogenic? Da. O. L.! i xtuxaT: Tint of all it was suggested that adust mask might be worn by the it. i engaged on the mining pnvess.! think thin H a perfectly practical suggestion and I we no rea ; why a mask should not be worn at this time. The time taken by the mixing process depend* on ih.amount being mixed but on average it takes S -15 min and it repeated at intervals of 2-4 hov>. I thank Dr. I tickoh for hit interest and with regard to the M.A.C. for asbestos dust I do t feel qualified to comment. 1 am quite prepared to accept his figure of 30 partidcs.Vm* as a * reasonable M.A.C. for fibrous particle^ and I agree that this means that the dust heard h grtakr than 1 had previously implied. I am grateful to Mr. Luton foe Ms contribution on the part that can be played by the Faster; Inspectorate. I agree that in the past the diagnosis of asbestos!* has depended mainly on the X*ray but that *c diagnosis is now occasionally being made before radiological abnormalities are apparent Dbgne.it depends on the demonstration of persistent crepitations at the King bases, and pulmonary ftkXWi tests may also be some help. We do not know to what extent this may have influenced the Ccrttcation figures. I was asked whether the particle star range that we measured is outside tha mpirchle rags. i am sure that it is not. I agree that a spherical particle of 50 * diameter would drop like a stone hr the fibrous particles of asbestos are very fight and float in the air much more readily* Yetasil remember that fibres recovered from the human fung have measured up to a in hngthl lam very grateful to Dr. Smither for coming here and making such an impressing contributi to the discussion. He said that he had crossed swords with me before but this is not strictly tr.c Our relationship hat always been most friendly and I hope that it always will be so. Today. I grateful to him for the information he has given us and for the interest he has shown in my par.' -H a o PO o OT CO 00U 06092