Document XR1BLd47NaL06O41D0kYGejny

r-ical a"d :low conditions similar to those that often prevail in practice, experimental ...jd-' ' jtf-ce<i suggesting that the electric wind makes a significant contribution to gas ..its and so probably should be considered In any comprehensive analysis of precipitator <ft' There are 13 references. ..Jfsnsca- --Author's a-tb-~s-t. in the roundry. Anon. Michigan's Occ. Health Ji_3, No, 2, --5 ('.Vinter, l?o8). cent l vestUatlor. of foundries conducted by the Division of Occupational Health of the Department of Public Health, it was found that the Michigan foundry industry faces a ' 'iou# situation. 3ased on a survey of 291 plants more than 7r- of the employees of this industry i<!ri xooaed to serious health risks. Management in tew of these plants understands or Is ift **oed to handle the problem and little concern is currently expressed. The health problems ^he foundry industry can and must be overcome. The responsibility for providing a healthful ir' mu environment rests with foundry management. --Cond. from text , Resolratorv Disease In Hemp Workers. A. Bouhuys, et al. 1 Hay. Resp. Pis. 96. 150 (July. 1908). Abstr. of paper presented at annual meeting of American Thoracic Soc,, May 19-22, 1968. V jrkers in the soft hemp industry suffer from byssinosis caused by dust Inhalation; acute dust e<posure causes a decrease of ventilatory capacity in them as well as in healthy subjects Souhuys et al.. Arch. Environ. Health 533, 1967 l. The authors studied the arevalence of chronic respiratory symptoms, forced expiratory volumefFEV^ q), and smoking -.aoits in 216 men with histories of prolonged exposure (20 years or more in 76 per cent) to hemp dust, and in 283 men in farming and other industries. Eighty-seven per cent of the hemp workers gave a history of byssinosis (chest tightness and/or cough on Mondays during work in gu4(). --Authors' abst. cond. j aole of Silica in Progressive Massive Fibrosis. In Coal Workers' Pneumoconiosis. P. C. Pratt. .Arch. Environmental Health_l_6, 734-737 (May, 1968). The hypothesis that silica Is the cause of progressive massive fibrosis in coal workers' pneumoconiosis (CWP) would be supported if more silica were present in fibrotic than in nonfibrotic tissue of lungs from coal workers. The present recalculation of data from a previous paper designed to test this hypothesis shows that there 13 an average of more than twice as much silica, in grams per lung, In fibrotic tissue as compared to nonfibrotic tissue in 17 coal workers' lungs. Excess silica is present in progressive massive fibrosis (PMF) tissue of every lung. It is concluded that silica is responsible for the fibrotic component seen in PMF and that continued search for other fibrogenlc mechanism is,unnecessary. The excessive local accumulation of dust at certain sites In the lung which permits local concentration of silica to reach levels capable of eliciting fibrosis may be due to coexistent eentrilobular emphysema, caseous foci, or scars. Further study of the actual mechanism is suggested. There are 15 references. --Author's summary Tltrasonic Examination of Pleural Thickening and Calcifications in Occupational Asbestosis, M Viikeri, J. Jaaskelair.en, and E. Tahti. Diseases of Chest -t, 17-20 (July, 1968). The roentgenologic diagnosis of occupational asbestosis is based upon typical pulmonary fibrosis ar.d anteriorly detected pleural calcifications, which appear much later than parenchymal changes Therefore, a definite diagnosis usually demands a long observation period. We used ultrasonic A- and 3-mode methods to examine pleural changes in nine occupational asbestosis patients ar.d five normal persons. In normal persons the parietal pleura was shown as a thin, sharp line when the 3-mode method of examination was used. Hoentgenographlcally observed calcifications were easily detected and dtstir.auished :rom the normal pleura by this examination. It is note worthy and similar echo peaks were seen in A-mode examinations in lateral ar.d posterior pleura, where roentgenograms did no: reveal pleural calcifications, ar.d their size could be traced wed with the 3-mode examination. Thus It is possible to find early pleural changes, which, in our opinion, are connected with occupation!, asoestosis. Diagnosis could be made earlier witho :: a long o-.servatior. r.m.o. There are ? references. --Authors acst.