Document KRRrJ4dqg5wnK5J8z9w3B6kpr

-<*. 'V Industrial Hygiene Digest November isr~ This effect was evident also in a subgroup of the men studied who reported no signs of mild bronchitic sv-- toms (cough and phlegm for at least three months in a year) . Among men with pneumoconiosis there was -- evidence of a reduction of FEVj q in excess of that attributable to their dust exposures, smoking habits, s-e and physique. Increasing severity of bronchitic symptoms was associated with a loss in FEV^ q greater than that expected from the effects of dust exposure as measured, smoking, age, and physique. Possible planations for this phenomenon are discussed . It is suggested that the results may indicate that once earlv bronchitic symptoms are present the disease may progress and ventilatory capacity may deteriorate inde pendently of factors initiating the disease process. --Authors' abs;. 1367/73 Asbestos in the Work Place and the Community. M.L. Newhouse. Ann. Occ. Hyg. Ijk 97-102, Aug. 19:; 17 refs. The fibrogenic properties of asbestos dust were detected early, later knowledge accumulated about the car cinogenic properties of the mineral and a hazard of bronchial carcinoma and mesothelial tumours was recog nised . Mortality studies have measured the effect of exposure on working populations. Recent analysis of data from a cohort of asbestos factory workers shows that even with low to moderate exposure there is exceu mortality from cancer of the lung and pleura and other cancers, after more than 25 years' observation. Th; mesothelioma rate increases both with severity and length of exposure. Occurrence of these and other tu- --mours appears to be dose-related. The markers of a community effect of asbestos dust in the environment are the occurrence of mesothelial tumours in neighbourhoods of a source of asbestos dust, and the presence of asbestos bodies or calcified asbestos pleural plaques in the general population. Conditions giving rise to neighbourhood mesothelial tumours may not now occur, but the importance of adequate control in all coun tries where asbestos is mined or manufactured is stressed. --Author's abs:. 1368/73 Hiatochemical Study of Asbestos Fibre Coating in Experimental Carrageenin Granulomas . M. Governs and C. Rosanda Vadala. Brit. J. Ind. Med. 30: 248-252, July 1973. 12 refs. To study the composition of asbestos body coating, asbestos particles present in experimental i~u :geenir granulomas were tested histochemically for mucopolysaccharides, ferric and ferrous iron, haemoglobin, and haematoidin. The stains were applied on microscopical sections both untreated ar,a treated with ironextracting solutions and/or enzymes. The results indicate that asbestos is rapidly coated with haematoid*- ferric iron, and hyaluronic acid. --Authors' abst- 1369/73 Effects of Asbestos or Quartz Particles on the Mixed Cultures of Macrophage and 3T6 Cell. K. Xoslu and H. Sakabe. Ind. Health 10: 125-127, Dec. 1972. 1 ref. Study of pathogenesis of pneumoconiosis at cellular level has been hindered by the lack of a suitable mode- system. It may be assumed that the first reaction of cells to inhaled dust particles in alveolar cavity 16 _ phagocytosis by alveolar macrophages. The way in which this is followed by fibrosis is obscure. The^ toxic effect of silica on macrophages is documented, and may well lead to the release of factors respon for stimulation in fibrosis. There is a correlation between the toxicity of various silica particles to m twphages in culture and the capacity of these particles to stimulate fibrosis in vivo, but this relation dear in other particulate matter. In this report the authors have tried to observe the effects of varioU^J. on the model system at cellular level. --Cond - fr 1370/73 1371/73 Improved Techniques of Identification and Determination of Airborne Asbestos. L. BartosiewiczAm. Ind. Hyg. Assn. J. 34: 252-259, June 1973. 6 refs. Tb< Collection, identification and data analyzing techniques are presented for airborne mineral fibers \ong (of limitations of the techniques are discussed. It is shown that the adaption of a plenum 13/4 "^b^utj0n sample collection is important since it leads to a much more uniform particle collection and dii*n .d cetfc> aration of the asbestos particles from other solid airborne pollutants with the refractive index ' f-'- is shown to be accurate. convenient and useful in distinguishing asbbestos from other fibrous m .-Author analysis of this type the image analyzing microscope is a very valuable tool. yeetal. Brit. J- ^ A Radiographic Survey of Monumental Masonry in Aberdeen. T.A.L. Davies. 30: 227-231. July 1973. 12 refs. Aberdeen 1A*3r A survey of radiographic appearances of the lungs of monumental masonry workers in c0lr,p* out to determine the present prevalence of abnormalities and to serve as a standard for futur in view of changes in methods of working. No major change could be detected in the s**tu*,a`r in 1?"" workers in Aberdeen over the past 20 years but the different methods of survey used b> ' by the presen: study did not allow of strict comparison. Chest radiographs were reporte '^e tt.8s ers independently using the National Coal Board elaboration of the ILO classification ana a 22