Document x9Mj4dV16bjYnbDx3w645rD0

! INDUSTRIAL HYGIENE F. |g. Pedley, BA., M.B., D-P.H.j J. G. Cunningham, B.A., M.B., D.P.H. , ASBESTOSIS Fbank G. Pedley, M.D., D.P.H. the past five or six yeap that the population of Thetford TI industrial hygienists have be- Mines, P.Q., is quite stable. Sfifce come interested in the effects of this town is given over entirely to die asbjstos on the health of workers. ik mining and milling of asbestos the the| Province of Quebec a very -con- following death rates per 100,000 siderable part of the world's supply from tuberculosis in Thetford Mines of ksbestos is mined, and the industry and the Province of Quebec during has! been in existence for forty years the years 1926, 1927 and 1928 will be or pore. To our knowledge, how-- of interest. (Quebec did not enter evefr, no case of pneumoconiosis hah been reported from asbestos in Cant l adai and the general impression among m-inIers i-s that the d.us.t i-s no,t ,hazardj the registration area until 1926.) ___ . 2927 192S Hetfori Mine*------i76.s 124.5 112.7 Prorinar of Qne6rc_J2 I2J.8 121.1 ousJ It' is from England that the first casejs of pulmonary asbestasis have beck reported. Dr. W. E. Cooke, in 1924, published the history of a case of pulmonary fibrosis in an asbestoiJ In view of the fact that the popula tion of Thetford Mines is only about 12,000 it is to be expected that the death rates would fluctuate consider' ably from year to year. These fig worker. Since then a small literature ures, therefore, do not indicate an has | developed, which promises to]j undue mortality from tuberculosis in grodkr very much larger as time ggooeps oonn.. !j . II The cases of asbestosis so far re-! portttl--with the exception of four! Thetford Mines, Canadian asbestos occurs as a silky, fibrous form of serpentine in seams of varying width. Its analysis shows Rhodesian miners--have occurred inn;;. it to consist largely of magnesium the manufacture of asbestos; but it silicate, but there is usually some iron is qiltite passible that the condition in present. Mining is carried on in open mines may have gone unrecognized, quarries, and is not usually a very for pines are usually situated in the dusty job, but in the milling a great counby, whereas factories are apt to be ik the city where facilities for autopsies are better. If, however, miners were seriously affected by deal of fine dust is created, and men who work there are heavily exposed to whatever hazard may exist. As mentioned above, however, it is the asbestoss' the effects should be reflected in a high tuberculosis death rate, providdeec^j the mining population was fairly general impression, both among miners and physicians, that asbestos dust is not particularly harmful. There stationary and did not go to. sanatoria can be little doubt, however, that the or elsewhere to die. It is believed | disease, asbestosis, is a clinical entity. t Industrial Hygiene and it has beek recognized by the Eng lish authorities to the extent of its inclusion as a compensatable disease. (See: Jcur. Amer. Med. Assn., June 28, 1930, p. 2078.) Pathologically the lungs of an in dividual afflicted with asbestosis show a diffuse fibrosis, not unlike silicosis in the gross. Microscopically, how ever, the appearance is different. For one thing large particles of dust morphologically similar to asbestos dust can be found in the fibrotic areas. In silicosis the siliceous particles are very difficult tis see and are very much smaller. In addition to the large par ticles of dust! sections of the lung show yellowish*, elongated bodies from 20 to 100 microns in length, usually dumb-bell shaped and often seg mented. These are the "curious bodies" and have been described everywhere asbestosis has been re ported. Theirj origin is not known, but it is thought that they are aggre gations of protein material about a central spicule of asbestos. Unquestionably these "curious bodies" have stimulated much interest in the disease, asbestosis. Patho logists, whose interest in such a dis ease might languish, become alive at the sight of jthe "curious bodies". From the public health standpoint, however, it seAns hardly likely that '^asbestosis will jbecome of importance either from the standpoint of mor bidity or mortality. The following is a fairly complete list of articles' bn the subject to date: 1. "Effects of ksbestos Dust on Work ers' Health I in Asbestos Mines and Factories", j Labour Gazette, Feb., 1912; 761. 2. "Fibrosis of the Lungs due to the Inhalation of Asbestos Dust". W. E. Cooke, Brit Med.' Jour, July 26. 1924. p. 147. 3. "Pulmonary 'Asbestosis in its Clinical Aspects". Thos. Oliver, Jour. Ind. Hyg, 9,483, Nov, 1927. 4. "Pulmonary Asbestosis". W- E. Cooke, Brit Med. Jour, (Dec. 3. 1927). 1024. 5. "Histology of Pulmonary Asbestosis". W. E. Cooke, Brit Med. Jour, (Dec. 3, 1927), 1025. 6. "Asbejtosis". McDonald Stuart Brit Med. Jour, 1927, ii 1025. 7. "Pulmonary Asbestosis in South Africa". F. W. Simson, Brit Med. Jour, May 26, 1928, pp. 855-857. 8. "Asbestosis". M. J. Stewart Brit Med. Jour, 1928, ii 509. 9. "Asbestosis". H- E. Seiler, Brit Med. Jour, it, 1928:982. 10. "The Presence of Asbestos Fibre in the j Lesions of Asbestos Workers". S. JR. Gioyne, Tubercle, June, 1929, p! 405. 11. "A! Case of Pulmonary Asbestosis". W- B. Wood & D. S. Page, Tu bercle, July, 1929, p. 457. 12. "Asbestos Dust and the 'Curious Bodies' Found in Pulmonary Asbes tosis". W. E. Cooke; Brit Med. Jour, Sept 28, 1929, 578. 13. "dinical Aspects of Pulmonary As bestosis". A. C Haddow, Brit. Med. Jour, Sept 29, 1929, 580. 14. "Further Observations on Pulmonary Asbestosis with Special Reference to Asbiestos Dust and the 'Curious Bodies* Found in the Lungs". W. E. Cooke, Jour. Royal Micro scopic Soc, 1930, vol. 50, p. 15. 15. "Pulmonary Asbestosis. A Socio medical Study". Arehiv fur Gewerpepathologie tmd Gewberhygiene, ' Sonderabdruck aus 1. jBand tmd 2. Heft 1930. 16. "Asbestos". Occupation & Health, International Labour Office, Brochure No. 27. 17. "The Occurrence of Pulmonary Fibrbsis and other Pulmonary Affec tions in Asbestos Workers". Ei R. A. Mere-wether, Joum. Indust Hygiene, 12, 198-222 and 239-257, May and June, 1930.