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Industrial Hygiene Digest INDUSTRIAL HEALTH NEWS LITERATURE ABSTRACTS MEDICAL ENGINEERING CHEMICAL TOXICOLOGICAL LEGAL-. - decisions and trends ARMED FORCES OCT 3 1955 MEDICAL LIBRARY OCTOBER, 1953 (Vol. 19, No. 10) INDUSTRIAL HYGIENE FOUNDATION MELLON INSTITUTE 4400 FIFTH AVENUE PITTSBUBGH 13, PA. PLAINTIFF'S EXHIBIT 1 WV-Q04&4 Industrial Hygiene Digest October, 1955 1^37 Adsorption of Serum Proteins at the Surface of Silica; Its Possible Tm - ~,portan.ee in the Genesis of Silicosis. B. Fernis and M. Battigelli. Med, lavoro 46 1-13 {Jan. 1955). Italian with English summary. A series of recent hypotheses on the pathogenetic mechanism of silicosis is based on the adsorption of proteins by silica. The re search described was undertaken to determine which proteins are most likely to be thus adsorbed. Experiments were made in which serum albumins, gamma-globulins, and whole human serum were adsorbed on carbon, quartz, and Aerosil powder. The experiments show that human serum globulins, and particularly gamma-globulins, have a high tendency to be adsorbed on silica. It is held probable that the adsorption on quartz is followed by a denaturation of the adsorbed pro teins and that this phenomenon could have an importance in the genesis of silicosis. -- Cond. from English summary (Bull. Hyg. ) 1238 Rheumatoid Arthritis in Males: An Epidemiological Study of a Welsh Mining Community. W. E. Miall. Ann. Rheumat. Diseases 14, 150-158 "(June 1955). . It has been shown (IHF Absts. 180, 181, Feb. 1954) that some coal miners with rheumatoid arthritis and with pneumoconiosis have characteristic chest x-rays. To determine whether the progressive massive fibrosis was a causal factor in arthritis, a survey of rheuma toid arthritis patients was undertaken jp a Welsh mining valley, in which progressive massive fibrosis was common among the miners. The sur vey showed that, though the prevalence of rheumatoid arthritis among all patients with massive fibrosis is about 2. 7%, compared with 0.6% among miners without massive fibrosis, the prevalence of the disease in miners does not differ significantly from that among non-miners, and therefore it is unlikely that massive fibrosis predisposes to rheu matoid arthritis. It is concluded, therefore, that neither exposure to dust nor the lung changes of complicated pneumoconiosis pl4y a causal role in rheumatoid arthritis. "Heredity seems 'to-play a-causal role in rheumatoid arthritis, in Caplan's syndrome, and in Caplan chest x-ray findings without arthritis. -- Cond. from J. Am. Med. Assn. '.'3 A 1239 Pulmonary Disability in Asbestos Workers. K. W. Smith. Arch. Ind. Health 12, 198-203 (Aug. 1955). Respiratory disease experience among several thousand male and female asbestos workers in the United States and Canada is reported. Of all workers exposed to the fibers, very few develop asbestosis. This disease is insidious in onset and progresses slowly with continued exposure, causing respiratory embarrassment and cardiac failure. Expansion of die lung is difficult, and there is impaired gas transfer through the lung. Dif fuse, obstructive emphysema is not common. The typical x-ray pattern ?1HP Industrial Hygiene Digest m* * October, 1955 1 cannot be confused with other pneumoconioses. An x-ray survey of 1 708 employees in a milling operation showed that the majority had I normal x-ray patterns, that ten or more years of exposure were nec- 1 essary to produce x-ray changes, and that no cases of asbestosis were I found who had worked less than 20 years in the dust. The incidence and I duration of nouoccupational respiratory disease were not increased by I exposure. Asbestos does not predispose to tuberculosis, nor does it I aggravate an apparently healed lesion. There are several reasons for I different opinions expressed concerning the relationship of asbestosis I and bronchogenic carcinoma. Differences in asbestos fibers were I noted. -- Cond. from author's summary I 1240 The Effects of Inhaled Talc-Mining Dust on the Human Lung. G. W. H. | Schepers and T. M. Durkan. Arch. Ind. Health 12, 182-197 (Aug. 1955). I The talc mined in Northern New York State consists of a mix- I ture of talc, tremolite, and anthophyllite. Quartz is also present in I moderate amounts in the dust generated in mining and processing. The three constituents of the talc were present in the lungs of deceased em ployees. Quartz was present in significant amounts only when the men . had been additionally exposed in other mining industries. The histolog ical features suggest that tremolite may be the main pathogenic agent in provoking the characteristic "talc" lung lesion. The roles of talc and of anthophyllite have not been wholly excluded. The presence of quartz modifies materially the nature of the "talc" reaction, and the presence of "talc" dust in the lungs modifies both the response to quartz dust and the course of associated infection. Marked pulmonary vascu lar damage was present in cases where the quartz content of the lungs was highest, and this feature is in harmony with the tendency to cardiac deaths. Bronchitis, bronchiolitis obliterans, and bronchiolectasis are associated major findings in this series. ' -- Cond. from authors' summary 1241 Disabling Pneumoconiosis from Limestone Dust. A. T. Doig. Brit. J. In<n~MecL 206^r6^JuTyT955X Attention is drawn to the occurrence of cases of pneumoconiosis in limestone workers. This pneumoconiosis is associated with fibrosis of the lungs and, in advanced cases, with disability. The lesion produced is almost certainly silicosis, due to the free silica content of the lime stone. The pneumoconiosis hazard, in the mining and grinding of at least certain limestones, is considerable, in spite of the relatively low free silica content. Whether or not calcium carbonate can modify the action of silica, it would not apparently, judging from these observations, have any inhibitory effect. -- Author's summary 29.