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FILE NAME Insurance Industry INS DATE 1960 DOC INS082 DOCUMENT DESCRIPTION Medical Journal Article - Diffuse Pleural Mesothelioma and Asbestos Exposure in the North Western Cape Province Brit J. industr Med 1960 17 260 AAA COURT REPORTING DEPOSITION EXHIBIT 0 DIFFUSE PLEURAL MESOTHELIOMA AND ASBESTOS EXPOSURE IN THE NORTH WESTERN CAPE PROVINCE BY J. C. WAGNER C. A. SLEGGS and PAUL MARCHAND From the Pathology Division Pneumoconiosis Research Unit of the Council for Scientific and Industrial Research Johannesburg West End Hospital Kimberley and the Department of Thoracic Singery University of the Witwatersrand and Johannesburg General Hospital RECEIVED FOR PUBLICATION april 24 1960 Primary malignant tumours of the pleura are uncommon Thirty cases 22 males 11 females ages 31 to 68 of diffuse pleural mesothelioma are described all but one have a probable exposure to crocidolite asbestos Cape blue In a majority this exposure was in the Asbestos Hills which lie to the west of Kimberley in the north west of Cape Province The tumour is rarely seen elsewhere in South Africa by copyrightNOTICE This lawr Tidematerial 17 may U.Sbe Code protecle~ Mesothelioma of the pleura is regarded as an the lungs of the first case Case ) and secondly uncommon tumour In the last four years we have 10 of the cases came from a hospital to which seen 33 histologically proven cases 28 of these had some association with the Cape asbestos field and suspected cases of tuberculosis were referred from a large asbestos mining area This hypothesis could four cases had been exposed to asbestos in industry not be supported at once from the original histories The tumour is rarely encountered elsewhere in obtained from the patients for they included house- South Africa During the past five years with the exception of the present series no neoplasm of this nature has been diagnosed amongst 10,000 lungs examined at the Pneumoconiosis Bureau in wives domestic servants cattle herders farmers a water bailiff an insurance agent and an accountant none of whom were working on the asbestos mines at the time We therefore undertook a detailed Johannesburg or in the Pathology Department of the South African Institute for Medical Research investigation of their past occupation and place of residence and the association with asbestos ex- Higginson and Oettle 1957 did not observe a single case in their survey of malignant tumours occurring in the Bantu and Cape Coloured population of Johannesburg and the North Eastern Transvaal Our first necropsy specimen of pleural meso- thelioma with asbestosis was examined at the posure was discovered The cases are summarized in Table 3. Previous biopsy specimens were reexamined and new cases diagnosed including asbestos miners In only one case do the relatives deny that the patient either visited the asbestos mines or was exposed to asbestos Pneumoconiosis Research Unit in February 1956 This is a preliminary publication and the problem Case ) During the early months of that year one of us C.A.S. in the Northern Cape treated six patients with gross pleural thickening Pleural biopsies from two of them showed the features of mesothelioma In the ensuing two years eight further cases were found from this region and five from elsewhere in the Union During this period C.A.S. had become perturbed at the number of these unusual tumours occurring amongst his patients and stimulated an investigation At this stage there were two reasons to suggest that asbestos might be implicated First asbestos was found in is being intensively investigated The Asbestos Area of the North Cape According to Hall 1930 asbestos was discovered by Lichenstein near Prieska during his travels be- tween 1803 and 1806. Since then it has been established that the asbestos deposits extend from 20 miles south of Prieska northwards through the western part of the magisterial district of Hay to the eastern portion of the magisterial district of Postmasburg and finally to the western area of the 260 diffuse plEURAL MESOTHELIOMA 261 ASBESTOS MILLS FIG | Map of Griqualand West asbestos fields district of Kuruman Fig ) These deposits occur in the slopes of a range of hills covering an area of approximately 8,000 square miles Known as the Asbestos Mountains these hills extend more or less longitudinally between 22-30 and 23 E. The whole area is semi sparsely populated and apart from mining cattle ranching is the only important occupation In the Kuruman area several large tracts of land in or abutting on these mountains have been reserved for the aboriginal inhabitants and here whites may only reside in the immediate vicinity of the mines The type of asbestos mined throughout this area is crocidolite better known as Cape Blue Asbestos The chemical analysis of the fibre is given in Table . Crocidolite is the fibrous form of riebeckite and all stages of transformation from a massive riebeckite rock through lamellar riebeckite to asbestiform crocidolite occur in this region Magnetite is frequently associated with the crocidolite Vermaas 1952 Mining district in of asbestos first began in 1893 and gradually spread the Prieska northwards In 1908 production had begun in the Kuruman district Between 1916 and 1918 a large number of claims were taken up This northward trend has continued and in about 1950 mining started at Pomfret near the Bechuanaland border Table 2 Initially the ore was quarried in numerous small open cast workings This was followed gradually TABLE t CHEMICAL ANALYSES OF CROCIDOLITE from Vermaas 1952 AND AMOSITE Sio ALO F-- Fe Mg0 Cao Na K H OHO Tio Mav F Crocidolite 5194 0.20 18.64 19.39 137 019 6.07 0.04 031 2.58 - ~~ _ Amosite 49 47 0-63 15 35 63 6.57 052 052 0.02 20 007 233 0-25 61 0.01 Total 100 73 100.46 262 BRITISH JOURNAL OF INDUSTRIAL MEDICINE TABLE 2 POPULATION OF THE MAGISTERIAL DISTRICTS IN WHICH THE ASBESTOS FIELDS ARE SITUATED taken from Union Census 1921 and 1951 District Prieska Kurunian Hay Postmasburg Whites 1430 4,713 4.499 Population 1921 _ O s e whites Total { Whiles 4.879 16,698 ' 8.309 21,401 6.814 ~fi 13,313 Included in the Hay District : 3.361 4,818 2,757 4,887 Population 1951 whnes 10.847 10.847 23.779 9.631 : 21,019 21,019 | _ Total oo 14,208 28.597 12,388 25.906 by a type of shallow mining inclined shafting be- today the white prefers to live as close as came more common after 1930 possible and the children play on the dumps from According to Frood 1915 the quarrying was a the mine and mill family affair undertaken by the local inhabitants The men quarried the rock which was sorted and then hand cobbed by the women and children Hand cobbing consists of separating the fibre from the banded ironstone by striking the rock cob with a small hammer As the market was selective a Case Historics The following eight case histories illustrate various aspects of the disease and the different types of exposure to asbestos dust rotary sieve was sometimes used to grade the fibre Case 1.-B.P. a Bantu male 36 years of age born and eliminate the small particles of dust After 1920 was a mine labourer and was the first case grading it was bagged and weighed The asbestos was then transported by donkey wagon to the nearest head Before the establishment of the railway in this area between 1923 and 1930 such a journey could last as long as 10 days This transport was generally undertaken by white youths farmers sons under contract The white inhabitants played very diagnosed as a mesothelioma with evidence ofasbestosis He was born in the Kuruman district but it is not known whether he worked in the asbestos mincs He was employed on the Witwatersrand mines underground for two years and in the change rooms for a further 11 years A radiograph taken at a mine hospital on August 18 1955 showed a massive sided pleural effusion little part in actual recovery of the fibre being nearly and 3,000 ml of fluid was withdrawn He was admitted always employed in the role of managers or over- IQ the Witwatersrand Native Labour Association seers issuing stores and supervising the grading and Hospital on August 24 1955 and two days later aspira- TS weighing of the fibres Farming activities were and tion yielded 1,000 ml of thick gelatinous pus which are still carried out round the mines could be pulled out in threads He was treated with frequent aspirations and instillation of varidase but Since the 1939-1945 war the demand for crocido- without improvement and he died on February 15 ont lite has enormously increased The lucrative claims 1956 Martiny 1956 have been bought by registered companies others At autopsy the right thoracic cavity was occupied by have been abandoned As deeper and richer a large gelatinous tumour which displaced the mediasti- beth deposits have been found vertical shafts are being num and compressed the left lung The t 'mourhad NET, sunk However the mines with large shallow infiltrated the pericardium The right lung was com- deposits are still using the inclined shaft and tunnel pletely compressed by neoplastic tissue Fig 2 but the PTR and quarrying is still used by the few remaining right bronchial tree did not show any evidence of a smaller producers With the building of more mills primary bronchogenic carcinoma Histological sections of the pleural growth showed a papillary mesothelioma hand cobbing has diminished In 1915 the first Fig 3 There was evidence of asbestosis in both crushing mill was established at Koegas in the south lungs Fig 4 This was followed by a large mill at Kuruman operated between 1926 and 1931 where it was situated within 300 yards of the main street close to which cobbing was also done for a few years 1927-1930 This was followed by a mill at Prieska in 1930 which was completely rebuilt in 1957 Griquatown had a small mill in 1928. The practice today is for one mill to serve several mines in the immediate vicinity In the early days the manager and labourers lived within a few yards of their place of work and even Case 4. K.Ha. white female 56 years of age born 1898 was a social worker who could only have had a short exposure to asbestos as a child and probably a further slight exposure as a young woman She may have paid several short visits to the mines with her husband at a later period until She was born in Griquatown where she lived until she was 5 years of age Her family then moved to Kimberley where from 1916 to 1922 she worked as a clerk in an asbestos warehouse Her husband owned an asbestos mine from 1933-1940 DIFFUSE PLEURAL MESOTHELIOMA 263 FIG 2 FIG Right fung of Case ! showing a tumour compressing the lung substance FIG 3 Cellulasrtructure of tumour of Cise i and cosin 10 Haematoxylin FIG Sections of lung from Case I showing asbestos bodies ' 30 Haematoxylin and eosin . aac MY { t i) 7, =~ 4a x evo 2 * o er ~ < se aHe, DB ww x, *, ws re . twe sa < - wd %. Toys Se oY) G 4 - en . ra + om td re re ae + Dine ee : aa vs 2 . 4 4 F. e . ot 74 reel th ys 4 - 3 oe * eb f av, 1 ft + . Te a 264 BRITISH JOURNAL OF INDUSTRIAL MEDICINE a FIG On July 21 1954 FIG On July 7 1955 ee ot Fig On March 3 1956 Fig On July 3 1956 2 1 FIGS 5 6 7 and 8 -Radiographs showing development of tumour in Case 4 tt ne diffuse plEURAL MESOTHELIOMA 265 FIG Right lung of Case 14 FIC Histological sections of tumour from Case 14 Haematoxylin and eosin ~ 24 She was referred to the West End Hospital Kimberley on July 19 1954 because of dyspnoea and right chest discomfort of acute onset The chest radiograph showed a loculated pleural effusion at the right base coloured fluid was aspirated which on examination was found to be negative for M. tuberculosis but contained mesothelial cells arranged in acini At thoracoscopy in Johannesburg on August 11 1954 tumour nodules were seen on the parietal pleura Histological examination of the biopsy specimen showed a mesothelioma Deep therapy and active gold instillation in September 1955 caused initial regression of both the pleural fluid and nodules but did not arrest the progress of the disease She received a further course of ray therapy without improvement and died in January 1957. The liver was enlarged and nodular before death but no necropsy was done Figs 5 6 7 and 8 show the radiological development of the tumour in this case Case 14.-S.S. a Bantu male 40 years of age born 1918 was an asbestos miner He was born in the Kuruman district and as a child often played on the asbestos dump near an asbestos mine He subsequently worked with asbestos for several years being employed at an asbestos mine weighing fibre from 1938-41 In 1942 he worked on a Witwatersrand gold mine but returned to the Kuruman district in 1943 where he worked as a farm labourer until his final illness He was admitted to the West End Hospital on March 3 1959. He had been well until July 1958 when he became aware of pains in the right side of his chest In addition he had a slightly productive cough and short- ness of breath on exertion Chest radiograph on March 9 1959 showed obliteration of the right lung field Asbestos bodies were found in the sputum Needle biopsy showed histological features consistent with a mesothelioma AUTOPSY right chest was occupied by a huge whitish tumour which infiltrated the mediastinum extending through the diaphragm onto the superior surface of the liver A coloured effusion was present in the left pleural sac but the left lung was not affected The mediastinal cervical and aortic abdominal lymph glands to the level of the renal arteries were infiltrated with tumour In the right lung it was found that the tumour mass had infiltrated along the interlobar fissures The lobes of the lung were compressed into three small segments Fig 9 On histological section a papillary type of pleural mesothelioma was seen Fig 10 which had infiltrated into the lung parenchyma in some areas There was marked lymphatic spread throughout the 266 BRITISH JOURNAL OF INDUSTRIAL MEDICINE Jung substance Numerous asbestos bodies were present in the air spaces and occasional bodies and fibres were seen in the interstitial tissue The lung itself was markedly atelectatic Evidence of asbestosis was observed in the left lung haemoptysis He was referred to the Johannesburg General Hospital for investigation The chest radiograph showed gross pleural thickening with a basal pleural effusion on the left side He was admitted to hospital and on June 10. 1957 a thoracoscopic pleural Case 15.-S.S.V. a white female 42 years of age born 1916 is a housewife who lived on a mine near Johannesburg and was treated for tuberculous pleurisy for six months It was only after the histological diagnosis of a mesothelioma had been made that her biopsy was taken This showed the features of a mesothelioma On June 24 1957 an attempt at decortication was made The left upper lobe was stripped easily but the grossly thickened pleura was so adherent to the lower lobe that the attempt was abandoned Sections of the pleura confirmed the diagnosis of mesothelioma previous history was obtained In addition it was He died on December 13 1957 subsequently learnt that her father Case 22 had been born on the asbestos field and had a long mining history Case 16.-A.N.V. a white male 50 years of age born The patient was born in the Griquatown district and 1906 was a farmer who was born at Griquatown and went to school at Kuruman She spent most of her youth in the asbestos belt She has lived near Johannesburg for 20 years In March 1958 this patient developed right chest pain went to a village school near an asbestos mine From 1914-16 he transported asbestos in donkey waggons from Hay to Prieska During these journeys he often slept on asbestos bags In 1914 he worked in an asbestos mine and rapidly increasing shortness of breath She was for a month admitted to hospital and 2,500 ml of slightly blood- The patient became ill in December 1955 with vague stained fluid was removed from the right chest A substernal pain and dyspnoca A sided pleural thoracoscopic examination was carried out on July 27 when a small biopsy was taken but this consisted of fibrous tissue Bronchoscopy was normal and no neoplastic cells were observed in the bronchial washings effusion was diagnosed and he was referred to Mr. J. K. Bremmer in Pretoria There was no evidence of malignancy in bronchial and scalene biopsies Some apical pleural thickening and a dense homogeneous opacity at M. tuberculosis was not cultured from numerous speci- mens of sputa pleural fluid nor from the bronchial washings She was admitted to a Johannesburg nursing the base of the left lung was seen in the radiograph on August 3 1956. Thoracotomy Mr. Bremmer in February 1957 revealed a thickened nodular pleura home on October 16 1958 with a large mass on the left diaphragm A mesothelioma Radiographs then showed massive thickening of the was seen on histological section right pleura with fluid in the right chest At thoracotomy In April 1959 he was examined by Mr. J. D. Visser in Mr. Dennis Fuller the parietal pleura was 2 cm thick Kimberley who found small nodules in the subcutaneous hard as rock and stripped with great difficulty from the chest wall The visceral peel stripped fairly easily from the upper lobe but separation became more difficult over the lower lobe where the peel was thicker During the decortication a necrotic mass was found in the paren- tissue over the neck and chest A large firm mass was found in the thoracotomy wound and a mass was present in the left hypochondrium There was generalized lymphadenopathy and numerous nodules were present on the tongue Chest radiographs showed the left pleurai chyma of the left lower lobe At the base confluent with cavity to be obliterated He was one of the few cases to the diaphragm and perhaps the mediastinum was a hard develop widespread metastases craggy mass which could not be removed Histological sections of the specimen revealed an adenoid form of A biopsy of one of the subcutaneous chest nodules showed a similar appearance to those seen in the original ALAM tubular mesothelioma Subsequently three specimens of sputum were examined for asbestos bodies but none specimen from the pleura The patient died on May 22 1959. No necropsy was performed were found The patient is still alive April 1960 but her condition is deteriorating Case 24.-D.G. a white male 32 years of age born 1922 by profession an accountant was born in England RIE but came to South Africa as an infant He spent his Case 22.-D.A.B. a white male 68 years of age and early childhood in Kuruman and left at the age of 7. He farmer was the father of the previous patient Although later qualified as a chartered accountant in Kimberley a diagnosis of pleural mesothelioma was made in January 1957 it was not until July 1959 that details of medically In 1944 at the age of 22 he had been discharged unfit from the army because of a left pleural effusion his exposure to asbestos was obtained He was born in Griquatown and went to school there He worked in Kuruman Postmasburg and Griquatown until the age of 62. Between 1918 and 1932 he worked Neither then nor on many subsequent occasions were acid bacilli found either in sputum or pleural fluid His only subsequent contact with asbestos was the auditing of the books of an amosite mine in the as an asbestos miner underground and was mostly in Transvaal charge of blasting Between 1932 and 1944 he farmed in In September 1953 he complained of sided chest the district but returned to asbestos mining from 1945 to 1952 In January 1957 the patient consulted his doctor be- pains and shortness of breath A radiograph of the chest with showed flattening of the diaphragm on the left side obliteration of the costophrenic angle and thickening cause of sided chest pain with cough and slight the oblique fissure He was seen on numerous occasions DIFFUSE PLEURAL MesothelIOMA 267 FIG On September 11 1956 FIG 12 On August 23 1957 Fios it and Radiographs showing development of tumour in Case 24 from 1953 to 1957 A radiograph taken early in 1956 showed the development of a left superior mediastinal shadow which enlarged progressively Fig 11 and later the de elopment of diffuse nodular pleural thickening on the left During 1957 similar but less marked changes developed on the right side Fig 12 He consented to bropsy in June 1957 and at operation a diffuse pleural malignancy was present Sections of the parietal pleura only were removed and the histological appearances were those of a meso- thelioma He died on October 6 1957. A necropsy was not performed Case 30. G.Fa. white male 50 years of age born 1909 is a storekeeper with a history of industrial exposure He has never been near the Cape Asbestos Fields He was born in South West Africa and lived there until the age of 21. From the age of 21 to 26 he worked in a factory in the Cape as a maker and fitter He volunteered the information that he had worked con- tinuously with asbestos lagging pipes and boilers He remarked that the removal of asbestos lagging from old pipes created a very dusty atmosphere and that he would cough a lot at such work Between 26 and 32 years of age he worked in a factory in Johannesburg in a similar capacity but was not exposed to such heavy dust con- centrations For the past 20 years he had not been in contact with asbestos Enquiries were made from the factory in the Cape as to the nature of the asbestos used ,) and these have revealed that during the relevant periods Cape crocidolite was exclusively in use He was first seen on March 14 1959 complaining of cough pain in the right chest and recent onset of breathlessness Three pints of fluid had been aspirated from the pleura and cytological examination showed the presence of malignant cells The radiograph showed marked pleural thickening and pneumothorax On March 17 1959 a thoracoscopy was done The pleura felt thickened and the lung was collapsed and immobile Several biopsies were taken These showed the presence of a mesothelioma The underlying lung showed the presence of asbestosis He was treated with nitrogen mustard pleurally and his condition temporarily improved When last examined he complained of increased breathlessness Discussion In 1924 Robertson denied the existence of primary malignant tumours of the pleura and considered them to be secondary in origin Since then on the one hand Willis 1948 1953 and Smart and Hinson 1957 have supported Robertson's views while on the other hand primary neoplasms of this nature have been described by many authors in recent years These include Tobiassen 1955 in Sweden Belloni and Bovo 1957 in Italy Godwin 1957 in the United States and McCaughey 1958 268 BRITISH JOURNAL OF INDUSTRIAL MEDICINE in Britain Evidence in support of the mesothelial origin of these tumours can be found in the tissue culture experiments of Stout and Murray 1942 and Sano Weiss and Gault 1950 The variegated histological pattern of tumours arising from the mesothelium of the pleura was remarked on by Klemperer and Rabin 1931 Such a variation is appreciated when the mulupotentiality of the cells lining coelomic cavities are considered Maximow first demonstrated this feature in 1927 Novak 1931 stated that the mucosa of all parts of the Mullerian canal and the germina epithelium were derived from these cells Keasbey 1947 showed that in the embryo the metanephros Wolffian body genital dependent urogenital structures are the mesothelum mesonephros ridge and all derived from Campbell 1950 considered the presence of both epithelial and mesenchymal elements a major diagnostic feature In describing the histology of 1 of these tumours McCaughey 1958 demonstrated that either the epithelial or the mesenchymal element might predominate He classified his cases into the following four groups Tumours of epithelial character tumours of mesenchymal type tumours of mixed type and tumours of anaplastic type Using McCaughey's classification on our series of tumours the majority are as in Campbell's series of the mixed type Of the remainder a few showed the papillary tubular structure of the tumours of epithelial character and there were several of the anaplastic type One case had the appearances of a tumour of mesenchymal type but even in this case primitive tubular structures were seen Apart from the original case all the histological diagnoses were made on biopsy material Three of these biopsy findings were confirmed at necropsy In the remainder we have had to rely on clinical and radiological examination to exclude other primary sites of malignancy Following the work of Meyer and Chaffee 1939 1940 the possibility of demonstrating hyaluronic acid in these tumours both chemically and histochemically has been considered as a diagnostic aid Both these investigations are still in an early stage Harington 1959 Preliminary results of the histochemical experi- ments show that there is metachromatic substance in both the stroma and glandular structures of the tumours This metachromasia can be reversed by incubation with testicular hyaluronidase This material stains strongly with Hale's 1946 colloidal iron method The periodic acid Schiff technique has given variable reactions These results are not specific for hyaluronic acid but are strongly suggestive of its presence The amount of metachromatic substance in these tumours has varied considerably This we think is partly due to the fact that until recently we had not appreciated the solubility of hyaluronic acid in aqueous media and the majority of these tumours were fixed in 10 formol Further Lison 1953 states that the metachromasia of hyaluronic acid is optimal at a concentration of 10,000 and gradually decreases at higher levels When the high concentrations that Meyer and Chaffee 1939. 1940 found in their tumours are considered this variation in metachromatic properties seems to have been partially explained In addition with the great differences in the histology of the various lesions it would be logical to expect certain tumours with a marked adenoid appearance to secrete more than those with an essentially glandular structure Three of the five autopsies performed showed evidence of peritoneal metastases In the other two thoracic spread was observed in one case to the other lung and chest wall and in the second to the mediastinal lymph glands and pericardium Biopsy evidence of metastases has been obtained in two cases one from the omentum and the other from the subcutaneous tissue of the chest wall while a third patient developed an implantation rodule in the thoracotomy scar which showed a similar appearance to that of the previous biopsy specimen The first recorded case of carcinoma of the lung associated with asbestos was described by Lynch and Smith 1935 By 1955 according to Doll a total of 61 cases had been reported Included in these cases was one mesothelioma Cartier 1952 mentioned two cases of diffuse mesothelioma from Canadian chrysotile mine A further three cases were described by van der Schoot 1958 Unfortunately no indication is given in the literature regarding the type of asbestos to which the majority of recorded cases of carcinoma were exposed However discussion with management and medical officers of two of the factories in which the majority of the cases reported in Britain were employed suggests that most of these workers were handling chrysotile asbestos Wagner 1958 The possibility that some of these people may also have been exposed to crocidolite dust cannot be excluded Attempts to produce tumours in experimental animals by exposing them to asbestos dust have been made Vorwald and Karr 1938 were unsuccessful Lynch Mclver and Cain 1957 succeeded in producing tumours in mice but lung neoplasms in his control animals were far too numerous for the results to be considered significant On the other hand Schm^/hl 1958 working in Druckrey's laboratory has been able to produce sarcomas in rats This has occurred after subcutaneous and - tant Py Py Y 2 t . diffuse pleural meESOTHELIOMA 269 intraperitoneal inoculation of both asbestos fibres and dust He states that mineral asbestos was used but does not name the variety In our series of mesotheliomata histological evidence of asbestosis has been observed in eight of the 10 cases in which lung parenchyma was included in the specimen examined No lung tissue was present in the biopsies from the remaining 23 cases It was only in the four cases that came to necropsy that large sections of the lung tissue were available for examination In all of these specimens evidence of asbestosis was found At first it was thought that the presence of numerous asbestos bodies fragments of fibre and dust immediately below the pleural elastic laminae in these specimens might have been significant in the pathogenesis of the tumours However it is more probable that this distribution is a result of the marked atelectasis Similar features have been observed in atelectatic lungs of asbestos miners in which no mesotheliomas have been observed Pleural fibrosis has been a common finding in cases of asbestosis and in some cases large pleural plaques measuring up to 10 cm in thickness have been seen These plaques which were first described by Gloyne 1933 have been observed following exposure to both amosite and crocidolite asbestos dusts In these cases of benign pleural thickening no evidence of stromal metachromasia has been observed In all the histological sections of pleura examined in the cases of these mesotheliomas and in more than 100 cases of asbestosis no asbestos bodies fragments of fibres or dust have been observed beyond the pleural elastic laminae Three patients from the Kuruman district with clinical and radiological features consistent with those of diffuse pleural mesothelioma had markedly abnormal cells in the pleural fluid These cells showed no specific features to distinguish them from cells originating in secondary malignant pleural deposits nor from the grossly atypical cells sometimes seen in malignant pleural effusions As no biopsy or autopsy examinations were obtained in these cases they have been excluded from the series The pathological evidence for associating these tumours with asbestos exposure is not conclusive As previously stated only in eight of the 33 cases has evidence of asbestos been demonstrated Of these six had a definite mining history and one had been exposed to asbestos while lagging steam pipes The other case was born in the Kuruman district and nothing else is known of him until his arrival at a Witwatersrand mine at the age of 23. In the remaining 25 cases we can only present circum- stantial evidence of exposure to asbestos dust Table 3 Eighteen of these 25 cases were born in the vicinity of the mines and two arrived in the district as infants Of these 18 people 11 admit definite childhood exposure to the dust and two others were exposed industrially in later life In addition two patients with childhood exposure later worked in the asbestos mines Three cases arrived in the region at an older age but were employed either on the mines or in transporting asbestos A further three of these 25 cases have had industrial exposure and in only one case do the relatives deny any exposure to asbestos dust The four industrial cases are significant Two of the patients were lagging locomotive boilers and one was lagging steam pipes A man who was an upholsterer by trade was employed in making proof clothing from 1939-1945 As far as can be ascertained these people were never in the Griqualand district These findings tend to add support to asbestos being the common factor in the development of these tumours and to counter the suggestion that there may be some other environmental cause in the region of Griqualand West If asbestos dust is a factor in the occurrence of these tumours similar cases might have been expected from the neighbourhood of the Transvaal asbestos mines in the Pietersburg and Lydenburg districts where crocidolite and amosite asbestos is mined According to Vermaas 1952 crocidolite and amosite occur in the same seams in the Pieters- burg district As can be seen from Table , amosite is similar in composition to crocidolite In the past four years the lungs of 24 cases of asbestosis from the Lydenburg district have been examined In this material two cases of carcinoma have been observed The one was in a white miner with 19 years service who had an carcinoma arising from a bronchus The other case was a Bantu miner who had a peripheral tumour No service record was obtainable in this case Only one case of asbestosis has been received from the Pietersburg area All of these men were actually employed on the mines at the time of death the majority having had a relatively short service Our findings suggest that mesothelioma occurs 20 to 40 years or more after exposure to dust Until com- paratively recently the mining in the Transvaal has been on a small scale and there were no settlements in the vicinity of the mines The lungs of 20 asbestos miners from the Cape Asbestos Field have been examined in whom no mesothelioma was observed One autopsy specimen consisting of three fragments of lung showed asbestosis and an carcinoma Radiological features of asbestosis have been observed in many miners from this region without any suggestion of 270 BRITISH JOURNAL OF INDUSTRIAL MEDICINE 1 Case No L 2 3 4 ... 6 . 8 20 10 STI STI 13 15 ** ** ** 19 28 21 22 22 a a 26 27 28 29 30 31 32 33 2 Year of BirtBh irth 1920 - 1913 1902 1896 1925 1903 1920 1894 1905 1909 1898 1910 1909 1918 1916 1896 1911 1920 1922 1906 1912 189 1889 1895 1922 1899 1895 1904 1899 1913 1909 193 908 1890 TABLE ] DIFFUSE PLEURAL MESOTHELIOMA ASSOCIATION WITH ASBESTOS 3 4 Age al Diagnosis Race Sex 6 Born on Asbestos Fields 36 B / 41 53 MXD * / F w * F kuw *** M 4 kuw *** kuw *** 1 o MXD F 7 52 MXD 49 -- *** *** *** * * * 48 * 37 53 I 8 8 35 8 MXD IXL == M W IXL , H fl 1 W T " W T MXD F H t MXD 4 W F 1 * * W * LL * M - * F - * W X - 52 > X - 60 W X - ** W XX - 50 >> M - 44 > M 0 > X - S > H. - 7 Asbestos Exposure Other history unknown until came to the Witwatersrand at the age of 23 Mined asbestos from 1930-33 left area at the age of 27 Lived whole life in a location near an asbestos mill Lived on asbestos fields until the age of 5 worked in asbestos warehouse 1916-20 Spent all his working life in the vicinity of mines Lived all her life in the vicinity of mines Lived all his life in the vicinity of mines worked as a miner From the age of 24 lived in a village serving local mines often visited mines watched cobbing outside houses Whole life spent near mines digging wells Lived at the mine from age 7-17 years played on dumps and in mine as a boy returned to assist from age 21-25 Whole life spent near mines miner 1931-33 Lived near mines until the age of 17 miner 1927 Lived near mine until the age of 21. played with fibre as a child Whole life spent near mines msner 1938-41 played on dumps as a child Daughter of Case 22 lived at mine until age of 20 went to school near cobbing sheds Went to school near mines transported asbestos 1914-16 Lived on major wagon route till age of 15 several subsequent visits Whole life 1945.58 in the vicinity of the mines miner Family lived at mine miner 1938-1959 Spent whole life in village on wagon route to Kimberley Lived in the vicinity of mines until the age of 16 often on dumps as a child Whole life in the vicinity of the mines miner 1913-32 and 1945-52 Lived in the vicinity of the mines until the age of 30 Lived the vicinity ofa mill from the age of 1-7 a played on the dumpy as child Lived in a mining areu from the age of 10 to 18 years alter 1918 spent whole life in same town as Case 24 Mined and transported asbestos from 1929-33 as Overseer Born in North West Cape transported asbestos from 1920-24 Lived whole life on farm in mining area from the age of 12 transported asbestos 1916-21 Maintaining locomotive bosters 1931-45 Maintaining 1930-40 steam pipes in explosive factories Worked as filter on railways maintaining locomotive boilers dates unknown Making asbestos blankets for the Air Force 1939-45 No history of exposure to asbestos 8 Diagnosed on Biopsy Biopsy ! a 9 10 } Survival Necropsy Histological | Evidence of from A InitialInitial Asbestosis Symptoms i in months - t : fs i ~- - , - ' ~ - 7 - ~ - & 8 = 30 = ... 24 : . 1 l ' - 1 . : * ~_ ~ , ! > , > i - i ' . t t : - 4 . - - s 13 i 12 - Still alive . - 7 . a : Sullative Sullative 0 0 42 . ! 3 ,) : 2121 . ; Still : - g I 16 17 17 - 6 } 48 . : + 7 - 4 - 4 - + - : + -- - oa + - Staillil ve - 1313 8 1515 . SuSulll l alive - 3 - Sullative 6 -- 7 ~ i - a KEYS Column 4 Race W = Whne MXD = Mixed Coloured A = Bantu Column 6 - = Born on asbestos fields -- -- Not born on asbestoS felds 0 U...nknown Column 9- = Necropsy done = Necropsy not done * c Only small fragments of parietal pleurs submitted at autopsy for histological examination Column 10 = Positive histological evidence of asbestosIS ~ C No lung 1155ue submilled submilled of lung 0 33 Small fragments ^ ssuc no evidence evidence bul 4 asbestosis tumour formation However pleural involvement of individual susceptibility must also be con- has been a common finding in these cases Hurwitz _ sidered 1959 It is possible that there has not been a We wish to record the great assistance that we have sufficient lapse of time after exposure for tumour development in these cases Further the factor received in this investigation from the medical prac titioners of the Griqualand West District and the diffuse PLEURAL MESOTHELIOMA 271 thoracic surgeons and pathologists Pretoria and Durban We thank the Secretary of Health publish this paper in Johannesburg for permission to REFERENCES Belloni G. and Bovo G. 1957 Acta med patav 17 367 Campbell W. N. 1950 Amer J. Path 26 473 Contribution Cartier P. 1952 Arch industr Hyg 5 262. Contribution to the discussion Doll R. 1955 Brit J. industr Med 12 81 Frood G. E. B. 1915 Memorandum on the Asbestos Industry in the Cape Province Report of the Government Mining Engineer Union of South Africa pp 76-82 Cloyne S. R. 1933 Tubercle Lond 14 493 Godwin M C. 1957 Cancer Philad 10 298 Hale C. W. 1946 Nature Lond 157 8OZ Hall A. L. 1930 Asbestos in the Union of South randum no 12. Geological Survey of South Africa Africa Memo- Harington J. S. 1959 Personal communication Higginson J. and Octtle A. G 1957 Acta Un int Cuner 13,949 Hurwitz M 1959 Proceedings of International Conference of Experts ort Pneumoconiosis Johannesburg Feb. 1959 Churchill London In the press Keasbey L E 1947 Amer J. Path 23 871 Klemperer P. and Rabin C. 8. 1931 Arch Puth Chicago Lison L. 1953 Histochimie et Cytochimie Animales pp 332-337 Gauthier Paris Lynch K. M. and Smith W. A. 1935 Amer J Cancer 24 56 - Melver FA FA and Cain R. 1957 A.M A. Arch industr Hith 15 207 Martiny D. 1956 Proc Transy Mine med Offrs Ass 35 63 Maximow A. 1927 Arch exp Zellforsch 4 1 McCaughey W. T. 1958 J. Path Buct 76 17 Meyer K. and Chaffee E. 1939 Proc a, ae 1940 J. biol Chem 133 83 Soc exp Biol N.Y. Novak E. 1931 Amer J. Obstet Gynec 22 826 Robertson H. E. 1924 J. Cancer Res 8 317 Sano M1.9 E. Weiss 783 E. and Gault E. S. 1950 J. thorac Surg Schm^/hlD. 1958 Z. Krebsforsch 62 561 Smart J and Hinson K. F. W. 1957 Brit J. Tuberc 51 319 Stout A. P. and Murray M. R. 1942 Arch Path Chicago 34 951 Tobiasspen G. 1955 Acta path microbiol scand Suppl 105 van der Schoot H. C. M. 1958 Ned T. Geneesk 102 1124 Vermaas H. S. 1952 Trans geol Soc S. Afr , 55 199 Vorwald A J. and Karr J. W. 1938 Amer J. Path 14 49 Wagner JC JC 1958 Memorandum on Pneumoconiosis Pneumoconiosis Research in Europe Submitted to the C.S.I.R Willis R. A. 1948 1st ed and 1953 Pathology of Tumours Butterworth London Addendum By the end of June 1960 a total of 47 cases of mesothelioma had been identified In 45 of these a possible association with exposure to crocidolite has been established In one case a mesothelioma of the peritoneum was present THE JULY 1960 ISSUE The July 1960 issue contains the following papers Decompression Sickness during Construction of the Dartford Tunnel By F. Campbell Golding P. Griffiths H. V. Hempleman W. D. M. Paton and D. N. Walder A Comparison of the " " altitude and " " pressure Syndromes of Decompression Sickness By M. de G. Gribble Phosgene Poisoning Caused by the Use of Chemical Paint Removers Containing Methylene Chloride in live ventilated Rooms Heated by Kerosene Stoves By W. B. Gerritsen and C. H. Buschmann A Study on the Acute Toxicity of the aryl Phosphates Used as Plasticizers A. N. Worden and J. P. W. Hughes By H. F. Bondy E. J. Field Ine Aerosol Inhalation of CaNa E.D.T.MAosatil by Workers Constantly Exposed to Lead Poisoning By LJ Petrovi~ M. Stankovi~ M. Savi~ evi~and D. Poleti A Biochemical Study of the Urinary Protein of Men Exposed to Metallic Mercury Agnes R. Wells A Simplified Method for the Estimation of Nickel in Urine By J. Gwynne Morgan By J. C. Smith and Clinical Bronchographic Radiological and Physiological Observations in Ten Cases of Asbestosis By 3025 G. L. Leathart The Measurement of Occupational Mortality D. K. Liddell lung ol Observations on the Occupational Life History of the Coal Face Worker at Two Collieries By O. P. Edmonds and D. S. Kerr The Assessment of Electroencephalographic Changes and Memory Disturbances in Acute Intoxications with Industrial Poisons By B. Chalupa J. Synkov^and M. ev~ ^>k Book Reviews A number of copies are still available and may be obtained from the Publishing Manager British Medical Association Tavistock Square W.C.I. price 17s 6d BRITISH JOURNAL OF INDUSTRIAL MEDICINE VOLUME SEVENTEEN 1960 EDITOR L. G.NORMAN ASSISTANT EDITORS J. M. BARNES J. C. GILSON LONDON | BRITISH MEDICAL ASSOCIATION TAVISTOCK SQUARE W.C.1 No. 3. JULY 1960 Decompression Sickness during Construction of the Dartford Tunnel F. CAMPBELL GOLDING P. Griffiths H. V. HEMPLEMAN W. D. M. PATON and D. N. Walder oe .. A Comparison of the " altitude " and " pressure " Syndromes of Decompression Sickness M. DE G. Gribble . . +: .. se ve . . PAGE 167 181 Phosgene Poisoning Caused by the Use of Chemical Paint Removers Containing Methylene Chloride in ventilated Rooms Heated by Kerosene Stoves W. B. GERRITSEN and H. BUSCHMANN ln. . e - .- + ve an . 187 A Study on the Acute Toxicity of the aryl Phosphates Used as Plasticizers H. BONDY E. J. Field A. N WORDEN and J. P. W. Hughes . an we we . . 190 Aerosol Inhalation of E.D.T.A Mosatil by Workers Constantly Exposed to Lead Poisoning L. PETROVI~ M. STANKOVI~ M SAVI~ EVI~and D. POLETI e 201 Urinary Exposed Mercury A Biochemical Study of the SMITH and AGNES R. WELLS.. Protein of Men -. .. to Metallic . . C. 205 A Simplified Method for the Estimation of Nickel in Urine J. GWYNNE MORGAN . . 209 Clinical Bronchographic Radiological and Physiological Observations in Ten Cases of Asbestosis G. L. LeatHART . .e . . . . a - 203 The Measurement of Occupational Mortality D. K. LIUDELL a oe .e .. 228 Observations on the Occupational Life History of the Coal Face Worker at Two Colheries O. P. EDMONDS and D. Kerk a an - we .: os : The Assessment of Electroencephalographic Changes and Memory Disturbances in Acute Intoxications with Industrial Poisons B. CHALupa J. Synkov^and M. ev~ IK Book Reviews ve oe ve e .e e .e . . e ~- 234 238 242 The Relation Between G. NAGELSCHMIDT No. OCTOBER 1960 Lung sj Dust and .. . Lung Pathology in . +e .. a PAGE Pneumoconio IS . a -- 247 Diffuse Pleural Mesothelioma and Asbestos Exposure in the North Western Cape Province C. Wagner C. A. Slegos and Paul MaRCHAND .. o. ce va .. 260 Dust Diseases in Dundee Textile Workers W. LOCKHART .. ... ve +. A. MAIR D. H. SMITH W. A. WILSON and ss 1. os . +. . .. The Study of Observer Variation in the Radiological Classification of Pneumoconiosis W. Fay and R. AsHFORD .. a . an oe _ . .. 272 279 The Classification of Chest Radiographs for Coalworkers Pneumoconiosis ASHFORD 293 The Relationship of Byssinosis to the Bacteria and Fungi in the Air of Textile Mills PETER TUFFNELL . . .- a - .e -- .. Experimental Byssinosis PETER TUFFNELL an an a .. .. .. Sickness Absence Among Forestry Workers in the North of Scotland 1958. MCGREGOR Le ws os . an a DONALD an .. 304 307 310 Ecological Factors Affecting Efficiency and Health in Warships F. P. ELLIS Le .. 318 Book Reviews .. oe ve oe oe se oe . .. .. 327 Votl o Vu olum mee 17 .. .. + a te oo .. .. : : . 331