Document LJw20MEqE3XdE9g5OMz81B0nX

524 INDUSTRIAL HYGIENE AND OCCUPATIONAL MEDICINE of the radiographic technique used to take these films and a concise catalogue of descriptive terms. There is no doubt that the system, which has already given considerable assistance in quantitative studies of the prevalence and progression rates of coalminers' pneumoconiosis, is a distinct advance on previous classifications and could with profit be applied to other types of dust disease. The following table gives the outline of the classification, but details should be sought in the original. Qualitative Divisions Main Divisions Subsidiary Types Simple pneumoconiosis Mixed Pinhead Granular nodulation Homogeneous nodulation Cobweb Chronic bronchitic Complicated pneumoconiosis Multiple fluffy shadows Faint massive shadows "Cricket ball" shadows Bilateral reniform shadows "Angel Wing" shadows Quantitative Divisions Category 1-- Minimal " 2-- Moderate " 3-- Marked " 4-- _ Maximal Stage A--Ambiguous shadows Stage B--Massive shadows Stage C--Advanced massive shadows Stage D--Advanced massive shadows with pulmo nary distortion Alice M. Stewart [Bull. Hyg.]. The Physiological Response to Dust from Mine Locomotive Traction Material. L. T. Fairhall, B. Highman and V. B. Perone, Pub. Health Rep. 65:1003 (Aug. 11) 1950. The using of sand as traction material for mine locomotives has been considered a potential health hazard. The purpose of this study was to determine the relative safety of possible sub stitute-materials. Guinea-pigs: were, the test animals, and suspensions of various powdered materials or dusts were injected intraperitoneally according to the method of Miller and Sayers. The dusts caused a cellular reaction with the formation of peritoneal nodules. Quartz and silica sand produced severe cellular reactions. Definite cellular reactions were induced by Lyon Mountain ore tailings, magnetite, obsidian, slag no. 4 and traprock no. 3088. A mild cellular reaction was evoked by anthracite, bituminous coal, hematite and lodestone. Miller and Sayers have noted, at least in some instances, a correlation between the severity of the peritoneal reaction in guinea pigs and the pulmonary response in man. In this study it was noted that anthracite, bituminous coal and hematite, which are relatively harmless to man, produced only mild peritoneal reactions in guinea pigs, and that quartz, which can produce severe silicosis in man, produced a severe peritoneal reaction in guinea pigs. Fourteen photomicrographs are included. Adaptation of Authors' Summary. Advice to Pneumoconiosis Patients. A. MEiKLEjoHN,-Brit. J. Tuberc. 44:104 (Oct.) 1950. Meiklejohn stresses that the diagnosis of pneumonoconiosis involves, first, clinical investi gation; second, the occupational history embracing the whole working life, and, third, radiographic examination of the lungs. All three must be considered together, but the most significant is the clinical investigation. Mass radiography has now extended beyond tuberculosis surveys, and in pneumonoconiosisproducing industries finds increasing use in the early detection of the disease. In factory surveys without previous clinical examination the workman is advised that he is suffering from pneu monoconiosis. Such phrases in the x-ray report as "simple pneumonoconiosis/' "in an early stage,"