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FILE NAME Colonial Sugar Refinery CSR DATE 1950 Nov DOC CSR195 DOCUMENT DESCRIPTION Journal Article - Occupational Factors in Pulmonary Dust Disease EMBER 18 1950 Specimens ns illustrating t) be set some up in irector of pathology ents appointed honorary iatric clinic of the appointed honorary cal section honorary of the appointed honorary ion of the Royal th 1. Medical Politica Meeting : Clinical MeetingMeeting cil Meeting 1.A Ethics Com- rtant Notice to apply for any first communicated concerned or with edical Association ry 135 Macquarie appointments in ical Society Hall Services Limited tralian Prudential Federal Mutual ' Provident Club or other appoint- M.A. House 225 sbane Associated indaberg Medical appointments and any COUNTRY are advised in eir Agreement to ary 178 nents in ments in North South South tary 205 Saint tal all Contract a All governf those of the journal cannot il articles foroffered to THE he contrary be ne Editor THE House Seamer MW 2651-2 y the Manager Street Glebe ularity in the not accept any of receipt d within one others not In virtue of al Association he journal by nts and bookinning of any he rate is monwealth of i and foreign THE MEDICAL . VOL II37TH YEAR SYDNEYSYDNEYSYDNEY OF JOURNAL AUSTRALIA SSATAURTDAYURDAYSATURDAY NOVEMBERNOVEMBERNOVEMBER NOVEMBER 19501950 Table of Contents The Whole of the Literary Hatter in THE MEDICAL JOURNAL OF AUSTRALIA is Copyright ORIGINAL ARTICLES Page : ABSTRACTS FROM MEDICAL LITERATURE Occupational Factors in Pulmonary by Gordon C. Smith M.B. B.S. The Changing Face of Obstetric Dust Disease .. by Infection Infection by 777 777 Obstetrics and Gynecology .. .. +. 6 +) BRITISH MEDICAL ASSOCIATION NEWS- Arthur M. Hi M.D. D.G.O. F.R.C.S.E. 782 Scientific F.R.C.O.G. 782 Torsion of the Testis and its by S. H. Appendages Lovell Hepatitis Treatment Treatment with Brewer's Brewer's Yeast by Neville Davis M.B. Ch.M. in .. Australia Tuberculosi Australia Immunization Against Tuberculosis in and New Guinea by E. A. North M.D M.R.A.C.P. and D Jamieson F.R.F.P.S F.R.F.P.S M.R.C.P. B.Sc D.T.M. and H. .. .. 6. 1. : 767 767 790 792 CORRESPONDENCECOR- ESPONDENCE- The Australian Tuberculosis Association i | Acute Myocarditis ., ae . An Efficient Resuscitator OBITUARYOBITUARY Edward Albert Woodward .. 6... 6...) Pagi oe 80 801 . 81 81 . 81 .. 81 REPORTS OF CASESSquamous Epithelioma Case Reporbty V. of the Renal S. Howarth Pelvis Pelvis wee Handicraft REVIEWS Pye's SurgicalPortraits Paraphilic Portraits .. we ee eee oe ee ee Gynecology Obstetrics and Diagnostic Diphtheria Prophylaxis .. .. .. oe os ose ee Therapy Asthma and Gold Autobiography .. ce Lene ae ne ee we we we we ee A ee 797 . 798 ne 799 ee 799 ee 799 we 800 we 800 BOOKS RECEIVED .. 1... 800 LEADING ARTICLES A Considered Statement on PAS .. 801 CURRENT COMMENT- Advances in the Field of Cortisone and ACTH .. An Australian Contribution to Genetical Knowledge 802 803 DISEASES NOTIFIED IN EACH STATE RITORY OF AUSTRALIA wes AND oe TER- -- +. 811 GRADUATE WORK- The Graduate Conumittee in Medicine in the University of Sydney ee ne ee ee 811 NAVAL MILITARY Appointments AND AIR FORCE- eee eee ene 8 . MEDICAL PRIZES The Australian Orthop^dic Association Prize 1952 SI NOMINATIONS AND ELECTIONS ee eae .. 812 DIARY FOR THE MONTH ..) .. 6. we ee 6. MEDICAL APPOINTMENTS IMPORTANT NOTICE ee 12 812 EDITORIAI NOTICES 12 OCCUPATIONAL FACTORS IN PULMONARY DUST DISEASE By GORDON C. SMITII M.B. B.S. Industrial Health Unit School of Public and Tropical Medicine Sydney Health THE Third International Conference of Experts on Pneumonokoniosis held recently in Sydney under the auspices of the International Labour Organisation 1950 adopted the following definition of pneumonokoniosis a diagnosable disease of the lungs produced by the inhala tion of dust the term dust being understood to refer to particulate matter in the solid phase but excluding living organisms the term diagnosable indicating the presence of signs or symptoms but not always loss of function The implications and scope of this definition are very wide Whilst pneumonokoniosis in the etymological sense means dust in the lung and therefore is applicable to the pulmonary reactions due to all types of dust and fumes in practice it has been associated chiefly with silicosis asbestosis and in recent years with the lung disease due to coal diseases in which permanent fibrosis occurs and with characteristic radiographic abnormalities Of late it has become evident that acute semiacute and chronic pulmonary conditions may result from inhalation of a variety of dusts both organic and inorganic other than silica asbestos and coal Although the nature and severity of the tissue reaction vary according to the type of dust and conditions of exposure the term pneumonokoniosis can be applied to these conditions Read al a meeting of the Section of Public Health Association Tuberculosis Tropical Medicine and Industrial Medicine tralasian Medical Congress British Medical Aus- Seventh Session Brisbane June 1950 The Occupational History in Pneumonokoniosis Whilst the diagnosis of pulmonary dust disease should never be made without proper consideration of the occupa- tional history medical history clinical examination and radiographic findings the first is of special importance Unless there has been exposure to dust of a harmful nature matter there cannot be a pulmonary dust disease no what the medical history or clinical examination might indicate and no matter how closely the radio- graphic appearances of the lungs simulate those of pneumonokoniosis Thorough and detailed inquiries should be made about any process in which the patient may have been exposed to dust nature and conditions of the work the type of dust and duration of employment at the process Unless these particulars are obtained accurately the industrial history may be rendered invalid with resultant error in - diagnosis Negative evidence as to dust exposure is as important as positive pneumonokoniosis has been diagnosed in certain individuals with suspicious radiographic signs evidently on the film appearances alone for a proper inquiry as to the nature of their work would have revealed no history of industrial dust exposure in these cases Properties of Dust in Relation to its DiseaseProducing Capacity Although all dusts if inhaled in sufficient quantities may be regarded as being potentially harmful some are known to be considerably more injurious than others Important information concerning the potential capacity of a dusty environment to cause disease of the lungs can be obtained from a study of the following factors i the composition and nature of the dust ii the size of the dust particles iii the intensity of exposure as determined by a the atmospheric concentrations of the dust b the duration of exposure THE MEDICAL JOURNAL OF AUSTRALIA NOVEMBER 25 1950 The Composition of Dust An analysis for the chemical | tightly cemented type dust high in free stituents should be or mineralogical con- | generated because silica would he causing carried out on any dust suspected of rupture it more energy would be required to dust pneumonokoniosis should be and preferably the borne examined , The most injurious I The Particle Size of Inhaled Dust crystalline free silica component of an industrial dust is The pneumonokoniosis uncombined The pulmonary reactions silicon dioxide- j conference concluded case of fibrous dusts such that in the line free silica from amorphous or crystal- dusts the larger sizes as asbestos and certain vegetable in a combined are less severe while silicates that is silica in many mineral appear to be more harmful whereas form with the notable a hydrated magnesium exception of asbestos silicate are less harmful most injurious dusts dusts the smaller sizes seem to be the In general whilst particles of mineral free silica than except asbestos exceeding five microns in of minor importance the lower limit size are of the size Most minerals which contain proportion of silicates also contain some causing pneumonokoniosis has not of particles free silica compounds of other yet been determined as iron aluminium calcium magnesium elements such Particles of the harmful size range cannot be may also be present Because of the and potassium the naked eye and it is well to remember that seen with inhibitory influence of possible modifying or concentration of dust of this a dangerous free silica the analysiscertain substances on the action of in the air without being particle size may be present should be not only for free and ; contain fine harmful seen A visible dust cloud may combined silica but also where constituents indicated for other likely innocuous size particles as well as those of larger of especially producing a if these by themselves are capable The actual lung reaction themselves number and size distribution of dust In regard to metallic dust and depend upon the method by which dust is particles may be no question of the fume even though there the nature of the produced and parent material from which centration and chemical presence of silica the analysis of the atmospheric concon- is derived Experience in New South the dust investigations elsewhere is that Wales like that of atpapmrianiasnalt osfhtohueld be determined in order that a proper cases over 90 of dust at least 70 and in some suspected hazard may be made processes particles generated in industrial In the case of siliceous are up to three microns in size coal dust About % of other conditions being materials as a general rule and similar the higher the percentage are over particles and five microns only about % of sandstone particles in size Thus not only is there of opfrodfurceee sdiilsiecaasein a dust the greater is its capacity to relatively small production the larger a When pulmonary disease is caused by such particles settle out from the atmosphere particles but than the smaller sizes more rapidly atmospheric concentrations of portion of inhaled lungs most Further it is known that only a dust is retained permanently in the ^ eriodor both are dust or to a longer working physiological necessary Thus pneumonokoniosis has removed by ptahreticles of about five microns and larger being mechanisms of the nasal and Jeen found in men engaged in Continuous dragging bricks from upper respiratory passages have or patent kilns Tests in shown these men to be exposed New South Wales to very high con- In a recent review of this subject Hatch that particles smaller than one micron 1950 suggests centrations of dust containing about % of free silica The pulmonary changes in coal the principal contributors to silicosis produicntisoinze Vmoary walbde 1950 showed in animal "ortionto what one would miners are out of pro- expect having regard only to experiments silica of particle size down that amorphous found to 0.005 micron produces pro- h1e95fr0ee sfioluincad content of coal dust which Smith and Whaite lung changes and states that the rate of tissue averaged raction of sixteen 1.8 in the under 10 micron samples collected from the coal face of reaction to dust is inversely proportional to particle size On the other hand in Ive collieries in New South Wales but a long period the larger particles regard to asbestos it appears that are xposure seems of oniosis necessary to produce disabling pneumono- more harmful than the smaller and that in the lungs they act as mechanical rather than as chemical irritants Gardner 1938 Wyers 1949 states Asbestos which contains no free silica produces ^"lmonarydisease but the mode of a severe that dangerous fibres measure about 20 microns ore differs from that of the silica paratcitciloen of the, asbestos Dust Exposure The pneumonokoniosis conference agreed that an analysis material from which dust is derived does ecessity represent the not of industrial process composition of the dust inhaled in The free silica content of 1st may be similar or may be borne -creased compared with that appreciably increased or in the parent material dcuosrtdriinagl to the nature of the material and type of process The problems associated with - example in foundries are exposure of to mixed dusts ay comprise a mixture of interest Foundry dusts "noxide and other carbon free silica silicates metal particles as well as m carborundum and other abrasive particles ide may play some part in the materials Iron adows seen in production of the nodular silica in the radiographs and may influence the action lungs of certain foundry workers ected with silicosis One apparently - of the nodulation may also question whether "arent seen in films of grinders with synthetpinceuambornaoskiovneisosis is due to particles from metals he physical nature of or soft and substances whether hard and t Thus the wet influences their capacity to produce fact that work is being done in not necessarily mean that there will be sandstone ard despite the high free silica a serious dust cr- ek was wet and content of the rock soft little or no dust would be breaking it up whereas if it was of a dry : concentra- In general exposure is measured in of tions of borne dust and the period terms of the individual is time during which exposed to those concentrations the lhoinggheerr tthhee paevreiroadgeofconcentration of borne dust and the exposure the greater will be the risk of contracting pulmonary dust disease In the case of silicosis and related types of koniosis including asbestosis the disease is pneumonoof gradual onset and slow development usually It does not become evident until after exposure for a period of the actual time varying according to the type years of dust and industry Meiklejohn 1949 states that under present conditions in Great Britain silicosis in a diagnosable stage seldom occurs in under fifteen to twenty years to the risk and in regard to coal miners McVitteixepo1s9ur4e9 gives a similar period for the development of pneumonokoniosis Wales My own observations on a group of 416 New South coal miners showed that the average period of in the men with disabling pneumonokoniosis exposure was thirty years their average age being four years Asbestosis apparently occurs after a shorter exposure Thus Wyers 1949 who investigated 115 fatal cases of asbestosis found the average exposure had been 10-4 years more the Under conditions of intermittent exposure iit t iis s more difficult to predict the likely effect on lungs than dust the exposure was continuous but the severity of any NOVEM NOVEM hazard Howeven Mo exposures exposures In the cas period meter generally i months or w instances a reaction The liter acute or exposures to following n In April 1 weeks after of his indust he was engi From 1931 1 fifteen mont for two year in the sub- using a Wa pick for si His chest on had two occ left the 17 days the last bef exa of bilateral At autops silicosis of Microscopica immature fil to nodular a In Octobe Industrial H in the basei been employ picks and a Nevertheless from 1150 t Owens's dust in 1937 were doubt that t dust inhalati Occupati The most dust containi commoner p mining or ( surfacing of and mouldin in iron form milling silied brick industi facture of al handling of several of th specially mer but still cont Pneumonck other papers to asbestosis this country it is much :n cessing and example text In recent : 1949 and " of the respir silica coal ai due to vegeta I propose b lung disorder of them hav industries or carried out h 60 we should risks 1950 se would be tired to in the egetable "whereas be the mineral size are articlea ined en with ngerous present nd may | larger articles ced and ne dust that of En some dustrial % of articles Chere a es but rapidly only a in the = being cal and iggests may be orwald phous es pro tissue size --6 that maller -r than states centrawhich ; the nd the e risk mono- lly of ecome s the st and ditions seldom to the gives niosis Wales are in four osure Bes of years more an if - dust NOVEMBER -_ NOVEMBER 25 1950 THE MEDICAL JOURNAL OF AUSTRALIA hazard is usually lessened in such circumstances This might however not apply with very high intermittent exposures metal ic In the case of metallic and vegetable dusts the exposure period necessary to produce a pulmonary disturbance is generally much shorter than with other sometimes months or weeks or even less rather lostances a single exposure may be than years sufficient to In some cause a reaction contains The literature contains reports of the occurrence of acute or rapidly developing silicosis after short exposures to high concentrations of silica dust and following notes about a Sydney case are of interest the In April 1942 a man aged thirty years died three weeks after he had collapsed at work The significant details of his industrial history were as follows From 1917 to 1919 he was engaged in coal mining Cessnock for two years From 1931 to 1937 he was with the Water Board including fifteen months on rock work From 1937 to 1940 he was for two years a builder's labourer excavating in sandstone in the basement of a building Latterly he had been using a water pick but earlier had been using a dry pick for six months His chest had been examined by X rays in 1937 1940 on two occasions the second being some weeks after he had left the basement excavation work and again in 1942 17 days before his death It was only in the film from the last examination that the radiologist reported evidence of bilateral nodular fibrosis At autopsy aortitis congestive cardiac failure and silicosis of the rapidly developing type were found Microscopically the lungs showed generalized somewhat immature fibrosis mainly diffuse but with some tendency to nodular arrangement In October 1939 the New South Wales Division of Industrial Hygiene had investigated the working conditions in the basement of the building where this patient had been employed Water jets were fitted to the pneumatic picks and an exhaust ventilation system Nevertheless concentrations of sandstone was installed dust ranging from 1150 to 10,000 particles per cubic centimetre by Owens's dust counter were obtained The dust conditions in 1937 were probably worse than in 1939 there is little doubt that this patient contracted silicosis as the result of dust inhalation during the period 1937 to 1940 ! Before referring to these however I wish to make a ! few comments about the lung changes which have been observed in basalt workers and biograph operators in New ' South Wales Basalt Work Basalt or blue metal is a basic igneous rock composed essentially of a bearing feldspar with smaller amounts of one or other of the magnesian minerals and a little iron oxide Free silica is typically absent but may be present up to % Thus basalt is a silicate with 40 to 50 of silica in combined form Whitworth 1947 Badham 1927 described a case of fine fibrosis of the lungs in a man aged sixty years who for twenty years had worked in a blue metal quarry and crusher house and was exposed only to the dust of orthoclase basalt which contains no free silica This man died but an autopsy was not performed In recent years I have seen two men aged forty years and three years respectively who as far as could be ascertained had been exposed only to basalt dust The first man had been a crusher attendant for fifteen years at the same quarry as Badham's patient and the second had worked chiefly on the crusher and screens for thirty years at another blue metal quarry The radiographs both men showed a marked generalized fine type of nodulation throughout the lung fields in the film of the first man who was totally disabled there were also large shadows suggesting consolidation Biograph Operating Two brothers whom I first saw in 1947 were forty and forty years respectively and had aged both worked in the projection booth at the same suburban cinema elder for ten years and the younger for twenty years There was no history of exposure to dust in other employment The elder man complained of shortness of breath and loss of weight his brother of pains and tightness in the chest The chest radiographs of both men were similar and showed a generalized fine nodulation throughout both lungs Films of both men taken in 1949 showed no significant change since 1947 In 1946 the New South Wales Division of Industrial Occupations Dusts et cetera Associated with a Pneumonokoniosis Hazard Hygiene had found that the concentration of dust in the air of the biograph box in the cinema concerned was The most important risks are those where exposure to dust containing free silica is likely to occur Among the commoner processes involved are tunnelling excavating mining or quarrying in sandstone or quartz cutting and surfacing of sandstone or granite sandblasting dressing and moulding in foundries especially machine moulding in iron foundries if siliceous parting powders are used milling siliceous ores certain pottery processes in the brick industry chiefly dragging in patent kilns manufacture of abrasive soaps and powders manufacture and handling of refractory materials and metal mining In several of these instances and in a number of others not specially mentioned here the dusts are of a mixed nature but still contain significant percentages of free silica Pneumonokoniosis of coal miners has been discussed in other papers and will not be further considered In regard to asbestosis which is of very infrequent occurrence in this country all the evidence from overseas indicates that it is much more common in cessing and fabrication of example textile work than workers engaged in the asbestos in factories in asbestos miners pro- for In recent reviews of the literature Perry 1947 Doig 1949 and Middleton 1950 have described disturbances of the respiratory organs due to mineral dusts other than silica coal and asbestos and have discussed the reactions due to vegetable dusts I propose briefly to mention the more important of these lung disorders because although to my knowledge most of them have not been reported in this country the industries or processes involved in their causation are carried out here or may be conducted in the future and so we should be familiar with the possible occupational . risks ; approximately 6000 particles per cubic centimetre of air by the Owens dust counter the dust particles were mostly about half a micron or less in size The ventilation in the box was biograph result faulty A sample of dust obtained room in 1946 on analysis gave the from the following Total SiO2 .. .. .. Rare earth oxides AbOs Fez Cao ignition ignition ee Loss on ignition a Copper eee Fluorides sae P O a SO tee 6-0 48.0 17.0 6.7 2.0 Trace Present Present Present Following the discovery of the unusual pulmonary condition in the two brothers seventeen biograph operators from fourteen other theatres were submitted to X ray examination Their period of employment ranged from seven to thirty years and some had worked in badly ventilated booths However no evidence of a lung reaction resembling pneumonokoniosis was found Several authorities have investigated gases dusts from carbon arcs and the ventilation fumes and of motion picture booths MacQuiddy and others 1939 showed that some of the intensity carbon are ashes appear to cause mildly proliferative reactions when injected intraperitoneally in the albino rat They state that it might be deduced that if inhaled in sufficient quantities over long enough periods of time these ashes might cause a proliferative type of pneumonokoniosis On the limited evidence at present available and in the absence of autopsy studies it is not possible to say whet" nd the lung condition present in these basalt wepulmonary biograph operators is due to dust Furthexception the 780 THE MEDICAL JOURNAL OF AUSTRALIA NOVEMBER NOVEMBER 25 1950 responsible the question arises whether it has fibrosis or is merely present as inert deposits caused It seems reasonable to associate the radiographic abnor malities of the basalt workers with inhalation of dust at their employment but in the case of the biograph operators whilst occupational factors cannot be ruled out indeed one of these men was compensated for sil^>cosis as they were brothers and as examinations of other operators gave negative results a industrial ^tiology has to be considered Although these cases are incomplete I mention them in order to emphasize that with present advances in industrial activity and with increasing knowledge of pneumonokoniosis we must constantly be watching for lung conditions due to dust not only from new processes but also in industries and occupations where previously they have not been suspected Tulc Until comparatively recently asbestos was considered to be the only harmful silicate Now however there is evidence of several investigators that tale a hydrated mag nesium silicate which occurs in flaky and fibrous forms and is used in a number of industries may cause significant lung changes McLaughlin Rogers and Dunham 1948 described a case of pneumonokoniosis confirmed at autopsy in a man aged fifty years who had worked for thirtyseven years in a rubber tire factory where he had been exposed to a fair concentration of talc dust and who died primarily from rheumatic endocarditis There was much fibrosis in the lungs and curious bodies similar to absestosis bodies were present These authors con- clude that tale pneumonokoniosis and asbestosis are similar diseases and that pneumonokoniosis is probably caused only by the fibrous varieties of talc Graphite Doig 1949 and Middleton 1950 refer to recent reports by other authorities in Britain chiefly Dunner and Gloyne concerning pulmonary disease in graphite workers According to Harding and Oliver 1949 graphite plumbago which is a crystalline form of carbon may be mixed with up to 10 of free silica and with other minerals They point out that grinding of natural graphite produces the greatest dust risk and can lead to a disabling and fatal pneumonokoniosis which they describe as resembling both radiologically and histologically that of South Wales coal workers Other Silicates Abnormal reactions in the lungs of animals or man have been described following inhalation of dust from china clay mica sillimanite and fuller's earth Cement Cement is mentioned here because of its very widespread use and of questions which periodically arise as to its possible harmfulness The raw materials from which cement is made are chiefly limestone which has not more than about % of free silica and shale which may contain from 20 to 40 of free silica The finished product has practically no free silica Gardner and others 1939 examined 2278 employees from 11 making plants in the United States of America Only eight persons showed evidence of nodular fibrosis attributable to dust and in six of these exposure to silica dust in previous employment was presumably responsible Baetjer 1947 showed that in rats exposure to high concentrations of cement dust did not lower resistance to lobar pneumonia and did not produce any acute or chronic pathological changes in the lung tissue ; Metal Fume Fever The If tthhee forr known example of a minor pulmonary reaction me fever due to fume rather than to dust mostly ro mbi in exposure to zinc oxide fumes for example in or from welding on galvanized iron It is said to be caused also by fumes of other ineta.s When it is due to zine there is an acute febrile reaction or chill of short duration and with no permanent jung damage If other metallic oxides such as cadinium or manganese are involved a more serious pulmonary condition may ensue Cadmium Johnstone 1948 states that cadmium has probably more lethal potentialities than any other of the metals The inhalation of dust or fumes from cadmium compounds especially the oxide for example in welding on cadmiumplated surfaces from the ignition of cadmium and from the use of cadmium in solder produces irritant effects which may be severe in the respiratory tract perhaps with pulmonary ^demaand death Beryllium The literature on the pulmonary and other lesions affecting workers exposed to beryllium is now extensive many reports having been published during the past five years Abstracts of the various papers and articles were recently made in Australia by Taylor 1949 Two principal types of pulmonary lesion have been described an acute pneumonitis and a chronic diffuse granulomatosis A number of fatal cases have occurred It appears that the acute form which may follow a single exposure to toxic fumes occurs mainly among workers exposed to compounds in the extraction and refining of beryllium from the ore beryl usually within a few weeks : , of the first exposure The chronic or delayed form which resembles sarcoidosis is more persistent A period of from several weeks or years may elapse from the time of the last exposure to the onset and recognition of the disease This type usually occurs in persons who have been exposed to dust from fluorescent powders containing zinc beryllium silicate notably in the fluorescent lamp industry However eleven cases of the chronic type were recently reported amongst residents in the vicinity of a beryllium plant There was no history of occupational exposure Eisenbud and others 1949 Manganese Doig 1949 mentions that since 1921 a relationship between manganese and pneumonia has been suspected following reports from Norway and Germany In England Lloyd Davies 1946 found that men exposed to dust of oxides of manganese experienced a high incidence of a condition which be called manganese pneumonitis No permanent lung changes were observed Three years later Lloyd Davies and Harding 1949 reported that pneu- monitis has continued to affect manganese workers Firket 1950 states that chemical pneumonia which follows inhalation of dusts of manganese vanadium os~finium and beryllium resembles virus pneumonia both clinically and histologically and he questions whether the dusts themselves provoke the disease or whether they activate viruses Iron Oxide Doig and McLaughlin 1936 described a fine nodulation in the lung fields of welders who were apparently in good health Later following further clinical and radiographic studies by them and other investigators it became the evident that the pulmonary changes were due to deposition of iron oxide dust which is present in welding that fume and which is relatively opaque to X rays and they were not associated with symptoms abnormal physical physical signs or lessened capacity for work A similar condition has been reported in other workers than welders exposed to iron oxide Enzer and Sander 1938 made an autopsy examination of the lungs of a welder whose chest radiograph showed fine nodulation and who died following an accident there was no fibrosis in the lung tissue Anoia que to Case ou pletely and in more similar Sine experi metall siderai alumi have b The there alumi COS : therap when under indust -- -- --" of alu Sha diseas engag oxide furna ture ( accord and s Rid to be that t The for : alumi The Bre abrasi the lu A. mino matel timbe Cor chitis repor work elsew The other Ba the s cane the 3 respi work were broki revie one litis dust as probably compounds n cadmium nd from the fects which rhaps with er lesions extensive e past five ticles were Two princribed an matosis A -w a single g workers efining of Cew weeks arcoidosis weeks or ure to the e usually ust from silicate er eleven amongst mg plant Eisenbud ationship uspected England dust of ace of a is No ars later t p--eu- rs . which madium ia both her the er they ulation atly in radiobecame to the welding d that hysical dition xposed nation howed there NOVEMBER 25 1950 THE MEDICAL JOURNAL OF AUSTRALIA 781 According to Doig and Mclaughlin 1948 the changes due to iron oxide are not necessarily permanent In one case described by them the abnormal lung shadows_com- shadows_com- pletely disappeared some years after cessation of welding| and in another the shadows became less intense Dusts from compounds of barium and tin which are more opaque than iron are believed to behave similarly to the latter in the lungs Aluminium Since Denny Robson and Irwin 1937 showed that experimental animals exposed to quartz dust plus % metallic aluminium powder did not develop silicosis considerable interest has been taken in the question whether aluminium dust damages the lungs and conflicting reports have been published The recent pneumonokoniosis conference decided that there was no conclusive evidence that the inhalation of aluminium in any form prevents the development of silicosis in man or that aluminium powder is of value as a therapeutic agent in human silicosis or that it is harmful when used for this purpose There was some evidence that under certain conditions the inhalation of aluminium in industrial processes may be harmful and further there was experimental evidence that in animals the inhalation of aluminium dust aggravates pulmonary tuberculosis Pulmonary Carcinoma Where an occupation which is associated with an appar ently high incidence of lung cancer has involved dust exposure it is reasonable to consider carcinoma in a dis- cussion of pulmonary dust disease The problem has been reviewed briefly by both Doig 1949 and incidence of Perry 1947 lung cancer in They mention the Schneeberg the high miners in Saxony and in miners in the Joachimstal area in Bohemia Arsenic and radioactive ores are both considered likely causes in these cases They also refer to reports by various investigators which indicate that workers in chromate factories and those exposed to arsenic and asbestos have a high incidence of pulmonary cancer In a personal communication Dr. J. H. Blakemore of Concord advises that in a chromate factory in New South Wales which has been operating since 1944 and which at present employs about 100 persons all workers engaged in the various stages of production have an ray examination of the chest before starting work and at monthly intervals thereafter To date nothing to suggest pulmonary cancer has been found In its early years this factory had a number of cases of nasal septal perforation and skin conditions due to chrome and relatively high concentrations of chromates were found in the atmosphere Synthetic Abrasives Sharer and Riddell 1947 described an unusual lung disease with fibrosis in some cases fatal in workers engaged in the manufacture of corundum aluminium oxide The process involves treating in special electric furnaces a mixture of bauxite iron and coke at a temperature of 2000 C. Dense white fumes are given off which according to Jephcott 1948 consist mainly of alumina and silica Riddell 1948 states that the lung condition appears to be induced by an irritant of a chemical nature but that the precise agent has not been determined These findings are of interest because artificial abrasives for example carborundum that is silicon carbide and aluminium oxide have such widespread use in industry The observations of Smith and Perina 1948 and of Brunsgaard 1948 indicate that dust from synthetic abrasives when inhaled may produce nodular shadows in the lungs Vegetable Dusts A variety of respiratory disturbances some only of a minor nature have been attributed to dust from vegetable materials such as cotton flax hay grain bagasse and timbers Three examples may be cited Cotton A condition termed byssinosis chronic bronchitis and emphysema with a tendency to asthma has been reported particularly amongst room and blow.room workers in the spinning industry in Britain and elsewhere There are no specific ray or autopsy findings The literature has been well reviewed by Caminita and others 1947 Bagasse This is of interest to Australians because of the sugar industry here Bagasse or megass is sugar cane after the sugar has been extracted and is used in the manufacture of wall boards Since 1941 cases of respiratory disease bagassosis have been reported in workers handling bagasse England the persons affected were those engaged on a machine shredder which broke up the bales of bagasse Hunter and Perry 1946 reviewed the literature fully and described eleven cases one of the patients subsequently died of acute bronchiolitis and pneumonia arising from the inhalation of bagasse dust They considered the disease was most likely caused by fine vegetable dust however its exact ^tiologyhas not yet been determined Wheat Dust Investigations have indicated that exposure to wheat dust may result in asthma Duke 1935 and an increased liability to respiratory disease Smith and others 1941 The fine hairs of the grain are believed to be responsible at least in part for these reactions Prevention of Pulmonary Dust Disease The measures to be applied in the suppression and control of dust and for the protection of the workers are essentially the same irrespective of the industry and type of dust Briefly they include the following 1. The abolition of processes creating harmful dust If that is not possible the total enclosure of such processes in mechanically ventilated structures or their segregation from other operations in the factory Isolation can be applied either geographically or by time that is by carrying out a dusty process when no other workers are in its vicinity 2. The use of a harmless material in place of one that is dangerous 3. The removal of dust at its point of origin by local mechanical exhaust ventilation 4. The use of water or other wetting agent to dust from certain processes becoming borne prevent 5. Electrostatic precipitation 6. The provision of adequate general ventilation to dilute contaminated air 7. Maintenance of a high standard of plant cleanliness and housekeeping 8. Personal respiratory protection of the worker Respirators should be worn only when other methods of protection are not practicable or for jobs of short duration They should be well fitting comfortable and efficient and should be kept clean 9. Preemployment and periodical medical examinations including a radiograph of the chest of workers exposed to a dust hazard If these control methods or such of them as are applicable to a particular industry or process are conscientiously applied and maintained workers would be protected against hazardous exposures to dust Summary The term pneumonokoniosis is defined and its scope briefly outlined the need for a complete and accurate occupational history in the diagnosis of pulmonary dust disease is stressed The potential capacity of a dust to cause disease is dis cussed with special reference to its composition and nature particle size and intensity of exposure In addition to dusts containing high percentages of free silica others in which free silica is absent for example asbestos and certain metals are capable of producing severe pulmonary damage In most dusts asbestos being an exception the 782 782 782 THE MEDICAL JOURNAL OF AUSTRALIA NOVEMBER 25 1950 harmful particles are those less than about five microns in size Intensity of exposure which varies for different dusts depends on the atmospheric concentrations of dust and the duration of exposure Brief notes of a case of rapidly developing silicosis are given The main occupations and dusts associated with a risk of pneumonokoniosis are briefly discussed In addition to diseases caused by silica coal and asbestos reference is made to the radiographic abnormalities of certain basalt workers and biograph operators and to the pulmonary effects of talc graphite cement zinc cadmium beryllium manganese iron aluminium synthetic abrasives cotton bagasse and wheat The occurrence of exposed to chromates pulmonary carcinoma in workers arsenic and asbestos is mentioned Measures for the control of dust and protection of workers are stated Acknowledgements I am grateful to the following for permitting me access to clinical records of patients and for the loan of ray films the Director of Public Health New South Wales the Chairman Workers Compensation Commission of New South Wales and the Chairman Silicosis Committee New South Wales I am also grateful to Professor E Ford for helpful criticism and to the Commonwealth Director of Health for permission to publish this paper . References Badham C. 1927 Notes on a Fine Type of Fibrous Pneumonokoniosis produced by Silicates and other Minerals Report of the Director of Public Health New South Wales for the Year ended 31st December 1927 page 102 Baetjer A. M. 1947 The Effect of Portland Cement Dust on the Lungs with Special Reference to Susceptibility to Lobar Pneumonia Animal Experiments The Journal of Industrial Hygiene and Toxicology Volume XXIX page 250 Bruusgaard A. 1949 Pneumoconiosis in Silicon Carbide Workers Proceedings of the Ninth International Congress on Industrial Medicine London 1948 page 677 Caminita B. H. Baum W. F. Neal P. A. and Schneiter H. 1947 A Review of the Literature Relating to Affections of the Respiratory Tract in Individuals Exposed to Cotton Dust Public Health Bulletin Number 297 Denny J. J. Robson W. D. and Irwin D. A. 1937 The Prevention of Silicosis by Metallic Aluminium The Canadian Medical Association Journal Volume XXXVII page 1 Doig A. T. 1949 Other Lung Diseases due to Dust The Graduate Medical Journal Volume XXV page 639 and McLaughlin A. I. G. 1936 Ray Appear- ances of the Lungs of Volume I page 771 Electric Arc Welders The Lancet 1948 Clearing of Ray Shadows in Welders Siderosis ibidem Volume , page 789 Duke W. W. 1935 Wheat Hairs and Dust as a Common Cause of Asthma among Workers in Wheat Flour Mills The Journal of page 957 the American Medical Association Volume CV : Eisenbud M. Wanta R. C. Dustan C. Steadman L. T. Harris W. osis The B. Wolf B. S. 1949 Occupational Berylli Journal of Industrial Hygiene and Toxicology Volume XXXI page 282 Enzer in N. and Sander A. O. 1938 Chronie Lung Changes Electric Arc Welders The Journal of Industrial Hygiene and Toxicology Volume XX page 333 Firket J. 1950 Industrial Pneumopathies conference in Belgium December 1949 The Lancet Volume I page 225 Gardner L. U. 1938 Experimental Pathology Section V of Silicosis and Asbestosis edited by A. J. Lanza Oxford University Press New York page 257 H. L. Durkan T. M. Brumfield D. M. and Sampson 1939 Survey in Seventeen Cement Plants of Afmos- pheric Dusts and their Effects upon the Lungs of Twenty Hundred Employees The Journal of Industrial Hygiene and Toxicology Volume XXI page 279 Harding H. E. and Oliver G. B. 1949 Changes in the Lungs Produced by Natural Graphite British Journal of Industrial Medicine Volume VI page 91 Hatch T. F. of Dust 1950 Analytical Requirements for Appraisal Exposure paper not yet published presented to the Third International Conference of Experts on Pneumoconiosis ingHufnrtoemrthDe. HaannddlPienrgroyf KB.agM.asAs.e1B9 ri4ti6sh BJroounrcnhailoloiftiIsndRuessturlita-l Medicine Volume III page 64 International national Labour Organisation 1950 Third Inter- Conference of Experts on Pneumoconiosis THE MEDICAL JOURNAL OF AUSTRALIA Volume I page 14 Jephcott C. M. 1948 Fume Exposure in the Manufacture of Alumina Abrasives Review of Associated Physical and Chemical Factors Occupational Medicine Volume V page 701 Johnstone R. T. 1948 Occupational Medicine and Indus- trial Hygiene page 265. The C. V. Mosby Company St. Louis Pneumonitis Lloyd Davies T. A. 1946 Manganese Journal of Industrial Medicine Volume III page 111 British - monitis and Harding H. 1949 Manganese Pneu- Further Clinical and Experimental Observations British Journal of Industrial Medicine Volume VI page 82 McQuiddy E. L. Tollman J. P. La Towsky L. W. and Schonberger S. 1939 Tissue Reaction to Some Carbon Dusts The Journal of Industrial Hygiene and Are Volume XXI page 498 Toxicology McLaughlin A. Tale I. G. Rogers E. Dunham K. C. 1949 Pneumoconiosis British Journal of Industrial Volume V1 page 184 Medicine McVittie J. C. 1949 Pneumoconiosis in Coal Miners The Graduate Medical Journal Volume XXV page 618 Meiklejohn A. 1949 Pneumoconiosis The Graduate Medical Journal Volume XXV page 599 Middleton E. L. 1950 The Etiology and Pathogenesis of Pneumoconiosis paper not yet published presented to the Third International Conference of Experts on Pneumoconiosis Perry K M. A. 1947 Diseases of the Lung Resulting from Occupational Dusts other than Silica Thorax Volume pagepage 1 II Riddell Employees Pathologic Shaver Associated Journal of page 145 A. R. 1948 Pulmonary Changes Encountered in engaged in the Manufacture of Alumina Abrasives Aspects Occupational Medicine Volume V page 710 C. G. and Riddell A. R. 1947 Lung Changes with the Manufacture of Alumina Abrasives The Industrial Hygiene and Toxicology Volume XXIX Smith A. R. Greenburg L. Siegal W. 1941 Respiratory Diseases among Grain Handlers Industrial Bulletin New York State Department of Labour Volume XX page 33 Smith A. R. and Perina A. E. 1948 Pneumonoconiosis from Synthetic Abrasive Volume V page 396 Materials Occupational - Medicine H. Smith G. C. and Whalte M. 1950 An Investigation Investigation Investigation into the Incidence of Pneumoconiosis in New South Wales Coal Miners and its Relation to Dust Exposure at Selected Collieries paper not yet published presented to the Third International Conference of Experts on Pneumoconiosis Taylor C. R. tion 1949 The Toxicity of Beryllium Informa- Circular 15 Defence Research Laboratories Maribyrnong Victoria : Vorwald A. J. 1950 Problems in Pneumoconiology paper not yet published presented to the Third International Conference of Experts on Pneumoconiosis Whitworth H. F. personal_comunication 1947 personal_communication personal_communication Wyers H. 1949 Asbestosis Journal Volume XXV page 631 The Graduate Medical Medical THE CHANGING FACE OF OBSTETRIC INFECTION By ARTHUR M. HILL M.D. D.G.O. Melbourne F.R.C.S.E. F.R.C.O.G. Gynecologist to Patients The Women's Hospital Melbourne THE last fifteen years of the century have seen the greatest advances of all time vention and treatment of obstetric infection now ending in the pre- This is due predominantly to the introduction and development of modern chemotherapy and antibiotic therapy but impor tant contributory factors are improved bacteriological knowledge and methods of investigation and a clearer appreciation of the place of maternal resistance in com- bating infection It is proposed to review the major effects of these advances on puerperal morbidity on the death rate of the main bacterial types of puerperal and abortional infection infection and on modern obstetric practice at the Women's Hospital Hospital period Melbourne over the past ten years During that period 41,643 women 80 of whom had attended our own anto anto natal clinics were confined and 18,285 cases of abortion dealt of which 5175 were diagnosed as septic dealt were with The annual morbidity following the confinements is shown in Figure I. earliest years Sulphonamides were in use in the earliest of general yearsmore although the compounds employed were in In available toxic and less efficient than those now avianifelcatbiloen the dosage obstetric addition they were not always given in adequate and their use was largely restricted to therapytherapy of established infection However when it is remembered are that less than % of all cases of sulphonamide sulphonamide sulphonamide likely to be of a bacterial type responsive to sulphonamide sulphonamide Read at Gynecology Obstetrics Gynecology Congress a meeting of the Section of Medical Medical Australasian British Seventh Session Brisbane June Obstetrics and Medical 19159050 N therap in pu antibi 1944 i freely coinci therap tion o Roulir Gra of penic every 1 followed be given figures incidenc standard morbidit patients YEAR PER DEATHS D Of consi in the m main bact during th Hospital problem of that of fo cocci Stre pyogenes ; serious ty Bacterium streptococc will not b four main