Document xzEGOLzEk26j17De67e9nXe4E

?.sr INDUSTRIAL MEDICINE and SURGERY 7 Ifm Inurrtnl n4 Mai/iWw *t Tn/luetru Vo'umt 24 APRIL. I**%S Mclntyre-Saranac Conterence on Occupational Ckest Diseases SARANAC LAKE, NEW YORK-FEBRUARY 7, 8, AND 9,1955 Fob the fust time the McIntyre Research total of scientific attainments that eventually will Foundation and the Saranac Laboratory united bring all occupational diseases of the chest to in a shared enterprise: the "Mclntyre-Saranac praiseworthy control. Conference on Occupational Chest Diseases." Although this Conference and all of the preced These two facilities are bound together in high- ing seven Saranac Symposia offer no official pro minded dedication to acquire and disseminate nouncements, they have provided scientific pro precise information on occupational diseases of nouncements that long have influenced medical the chest and notably the dusty lung diseases. and compensation board concepts on occupational Essentially, both these organizations are devoted chest diseases. There is reason to believe that this to research investigations. The much that al latest Conference in equal measure will influence ready has been achieved chiefly reveals the in and, to some degree, govern the thinking and the adequacy of full understanding of the pulmonary action of many persons concerned with occupa occupational diseases and thus piques the reali tional pulmonary diseases. zation that the days of such research are not numbered. Major Disclosures in the Conference Beginning about 1933, the Saranac Laboratory glNCK this Conference is without any official inaugurated a series of Conferences entitled status, no pronouncements were made other "Symposia on Silicosis," the seventh and last of than by individual speakers. Still, there was tacit which was staged in Saranac Lake in 1952. The acceptance of many statements that in the ag published proceedings of these Conferences long gregate represent the consensus of beliefs as to have served as text and reference books on the pulmonary occupational diseases at this time. The dusty lung diseases to the point of having be total embraces the followiug: come authoritative. So great did the Saranac Silicosis as one dusty lung disease is common Laboratory influence become that the city of its to all industrial countries. Perhaps in no country location, Saranac Lake, New York, long has been are recording systems sufficiently complete to accepted as the Mecca of occupational pulmonary provide other than an estimate of the total num disease investigation. The numbered series of ber of industrial workers afflicted. One estimate symposia has given way to this, the first Mcln for the United States is that presently there may tyre-Saranac Conference, but the character of exist as many as 300,000 cases of diagnosable the program, the excellence of presentation, and pulmonary occupational disease, chiefly silicosis. the outstanding research work represented have While the widely acepted standards as to tol not been altered except that the output of the erable limits of exposure may be recognized as two outstanding organisations presaged an even far from exact, no justification is known to exist higher order of contribution. at this time for any sweeping modifications. The scientific status of both organizations These standards, which are official in some juris sponsoring this conference is such that enormous dictions are: responsibility rests upon all participants. What was said in the many sessions unfailingly will SobaUne* Million Particle* Per Cubic Foot touch industry, management, labor unions, com pensation courts, physicians, educators through out America and. even more, many other portions of the world. This imposed s doubly earnest, zeal Dv containing fro* liliet hifh (above 50% fro* SiOs) medium (4 to 50% free SiOtl low (below 5% fre* SiOtl 5 20 to ous and cautious approach to the tasks in hand. More than ever, silicosis is to be considered The Conference program, as devised by the both as to clinical and compensation appraisal program committee, was guided in its coverage sharply in connection with the degree or quantitv by Dr. G. W. H. Schepers, Director of the Sar of involvement. It is possible that a substantial anac Laboratory and Dr. J. W. G. Hannon, Medi portion of the adult population of the United cal Director for the McIntyre Research Founda States and presumably other countries harbor tion. a few demonstrable silica nodules without indus Not lightly statA the purposes of this Con trial exposure and the number may include house ference and its subsequent scientific publications wives never engaged in employment other than amount to the determination to add to the sum household duties. It follows that the mere de- t7i Induetrial Medicine and Surgery fhBy___ Ufa and la the abi dtoahfltty wnd by that The classleal allies nodule is the primary lesion of silicosis. Atypical nodules sack so tbs stellate form somstiaMS dsscrlbsd 9V Mt bs retarded so different lesions but only as modifications of the clsaaicsl form. In recent decades, exposition of the causation of silicosis presumed some decree of solution of the silica within pulmonary structures which solution products were labeled as the provocative agent. From silicates investigated under expert* mental conditions, more free silica solution has derived than from proportionate quantities of free silica. Yet, from silicate exposure (asbestos, talc, and perhaps similar minerals excepted) no characteristic occupational disease occurs and certainly not silicosis. At the present time, many evidences are arising that the causation of sili cosis in some manner is asaoclsted with particle surface action rather than simple solution, but the exact nature of this responsible surface ac tion remains undisclosed. As to aluminum therapy in the prevention sad treatment of silicosis, the results from animal investigative work at* substantial. It appears established that aluminum in more than one form but not all forms, hampers and limits the develop ment of silicosis, but perhaps exercises no ameli orative action on silica nodules already pre formed. The application of aluminum in the pre vention of silicosis in human beings, and, to a lesser degree, therapy for eases already estab lished, is attended by numerous supporting obser vations and investigations. The crucial appraisal of the worth of aluminum in connection with silicosis and its prevention awaits the results of fully controlled application. It is obvious that the establishment of a precisely controlled in vestigation is difficult and manifestly a prolonged affair involving years. No less, some uncertainty will continue to attend the use of aluminum in relation to silicoais until unequivocal results accrue from a well-planned, controlled investiga tion. For practical purposes and by long precedent, silicosis does not become significant until that stage of development ia reached which is char acterized by modifications mealed on the wellmade x-ray film. Inevitably, it must come about that prior to that time there must be indiscernible or little discernible evidence of abnormal pulmo nary tract structures, but the quantity of rv*1 changes is of such order that no disability exists and compensation for the Immediate situation ia not warranted. Compensation on an anticipatory basis pending possible progression of tbs dis ease and plans for future compensation may be in order but as to the "then and there status,** the pre-x-ray state of silicosis becomes negligible. dfifr Xafrtyre-Sarunas Conference, the early _____ _ te *be puonmn--iliuls. Ln, that ant*intlag r*y evidences of deviation from the Haul was reported as (a part related to Tmruluf changes with the ultimate prospect of damage to the right side of the heart eventuating la ear pulmonale. This may not be interpreted to tint now forms of silicosis or other pneumoconi osis have been disclosed which call for entirely new criteria for diagnosis but, in general, this newer work tends to emphasise greater cardiovas cular damage than heretofore has been contem plated. For a long time, it has been recognised thst a group of silicon-bearing compounds such ss talc has been the cause of pulmonary occupational disease. Otherwise this same talc as earlier used by aurgeona in connection with the lubrication of operating room gloves, has led to some culpation in connection with the inauguration of adhesion formation. In explanation, there has beeo the practice to aasert that enough free silica existed within the talc to induce these changes so thst what occurred in terms of pathology was not other than silicoais or at least a modified silicosis Now it appaars that talc, which is a silicate-like asbeato and some other silicates, through its own properties, ia capable of procuring damage and that which takes place is not sili< imi* A new primary lesion is believed to exist whuh lesion is not the silica nodules but more akin to the "a.. bestos body." If this be true, a disease heretofore regarded aa silicoais becomes a separate and distinct disease entity. For nearly four decades, enormous difficulties have attended the diagnosis and legal adjudica tion of claims alleging silicosis and disability or death therefrom. One of the emphasized features of this Conference was that much of this un certainty could be removed through the removal of small portions of lung tissues followed by ap propriate microscopic examination. Such exami nation of a properly chosen lung biopay specimen might yield such findings as speedily and definite ly to establish that the existing iiatholngv *a* Boeck's sarcoid or carcinoma <>r siliciMm <i an thracosia or talcoeis or tuberculosis. However it will be recognized that silicosis may exist along with tuberculosis and that asbestoeis could co exist with carcinoma. Still the potentialities of suitable microscopic examination well might re veal all such dualities as well as the single con dition should singularity exist. Precise as this procedure may be, its widespread practice or ap plication ia not likely to come about since the re moval of the required lung specimen in itself constitutes a major surgical operation. Notable Investigations While all of the numerous scientific presenta tions were notable, some individual papers and some groups of papers stand out aa except tionaL This number includes: "Observations on the Comparative Vascular Pathology of the Occupational Chest Diseases"-- G. W. H. Scbepers. ipd. i* 175 "The Value of Lung Biopsy in the Diagnosis of Occupational Pulmonary Diseases"--H. S. Van Ordatrand. . "Studies on the Prophylaxis of Experimental Silicosis by Means of Aluminum"--M. Dworski. "The Demonstration of Aluminum in Animal Tissues"--D. A. Irwin. One group of papers constituting a half-day program was devoted to the epidemiology of occupational chest diseases, on an international basis, all furnishing evidence that no country is the sole habitat of pulmonary occupational dis eases. Prominent in this group were: "A Review of Progress in the Conquest of Oc cupational Chest Diseases in South Africa"-- G. W. H. Schepers. "Accomplishments in the Epidemiologic Study of Silicosis in the United States"--H. N. Doyle, V. M. Trasko, Wm. Gafafer, S. E. Miller. "Silicosis in Canada"--N. F. Parkinson, A. R. Riddell. "Talc Pneumoconiosis"--M. Kleinfield, J. Mes- site, 1. R. Tabershaw. "The Dust Diseases in Great Britain"--A. I. G. McLaughlin. "A Correlation of Tissue Reaction and the Mineral Content of the Lungs of Experimental Animals"--P. C. Pratt, T. M. Durkan. As an exception to the general trend of dis cussion revealing the widespread existence of devastating occupational chest diseases was a report by Dr. Geoffrey E. Ffrench entitled "PneumoctiniosK <>n the Kolar Gold Field, South India." In this locale despite undenied high exposure to free -ihi a. the incidence and severity of silicosis was not remarkable. It was recorded that one natural c<>n-tituent of the total dust was a con siderable iN-rcentage of aluminum oxide. In guarded fashion, the question was proposed as to the possibility of this aluminum serving as a pre ventive agent further substantiating the moot claims as to the protection qualities of that ma terial. Continuing with this recital of high merit in manuscripts, the following were notable: "The Reaction of Chromium Compounds With Body Tissues and Their Constituents"--Anna M. Baetjer, C. M. Damron, J. H. Clark, V. Budacz. "Biochemical and Biological Aspects of the Surface Properties of Particulate Quartz"--L. D Scheel, G. W. H. Schepers. "Criteria for the Assessment of Disability in Occupational Cheat Disease"--G. F. Filley. "A Clinical Study of the Effects of Inhaled Calcined Gypsum and of Talc Mining Dusts on Human Lungs"--G. W. H. Schepers, T. M. Dur kan. "The Pulmonary Disability Associated with Coal Mining"--J. W. G. Hannon. "The Disability Found in Persons Exposed to Certain Beryllium Compounds"--H. L. Hardy. "The Pulmonary Disability Attendant on Asbestosis"--K. W. Smith. "The Experimental Study of the Effects of In haled Hydrous Calcium Silicates, of Calcined Gypsum, and of Talc Dusts on Animal Lungs"-- G. W. H. Schepers, T. M. Durkan. "The Experimental Study of the Biological Ac tion of Rare Earth Oxides and Fluorides, Tung sten Carbide, Cobalt, and Glass Wool on Animal Lungs"--G. W. H. Schepers, A. B. Delahant. At the Dinner session of the Conference the Leroy U. Gardner Memorial Address was pre sented by Dr. Paul S. Richards, of Salt Lake City. Utah. This in turn was followed by Historical Sketches on Dr. Edward L. Trudeau and Dr. E. R. Baldwin, by Dr. Hugh M. Kinghorn, who was himself a contemporary of Drs. Trudeau and Baldwin and who participated in many of the early laboratory investigations of tuberculosis in the United States and Canada. Distinguished Participants 'J'HE total number in attendance including the staffs of the two sponsor organizations ex ceeded 250, with representation from every sec tion of the United States. Representatives from countries other than the United States and Can ada included the following physicians, industrial hygienists, and attorneys: Dr. E. Balgairies, Douai (Nora), France; Dr. Nandlal Bordia. In dore, India; Dr. Maha Nand Gupte, New D-it. India; Dr. A. I. G. McLaughlin, London, S.W., England; Dr. Artemio Miranda, Lima, Peru; Dr. S. F. Oosthuizen, Pretoria, Union of South Africa; Dr. C. Kelman Robertson, Edinburg, Scotland; Dr. W. Jones Williams, Cardiff Wales, England; Dr. Geoffrey E. Ffrench, Kolar Gold Field, South India.