Document yrr4D9aK77R8M0rnNGXYNyR34

data, presented in tublu l, ia based upon coiaploted observations and therefore differ a slightly from a preliminary roportC^)^ Introduction of flno quartr into various organs of the guinea pig, rubblt, rat, nouse, cat, dog, chicken and even tadpolo eventually will produoo silicotic nodulos but at a different rate of development. Similar introduction of asbestoa haa rosuited in a fibrouo reaction In the lung and, to a losscr extent, in the peritoneum but not ia other organa of the guinea pig, .'abbit, cat and trhito rat. In our experience tho lungs of tho dog and r.hit > mouao failed to respond with fibrosis although Sohuntor^^ hao reported such ohangos in a dog that lived in an asbestos fabricating plc.tit. This variation in specios and in organ suacoptibility is yot to bo aocountcd for(^)j it lo presumed that in-thesusceptible anlmala tho grtutor reaction of tho lung to aebeatoa, far exceeding tho reaction of other organ tieeuoa, ia due principally to tho greater mobility of tho lung. . .. Pocullar ChamotorlntioB of Asbestos. Experience haa demonstrated that moot of the nen-fibroua particulate dust inhalad into tho lunge of man and animal lo 10 microna or leas in maximum dimension. Largor parti-- oleo apparently do not gain aoooso to tho lunge because of two roasonsi first, largo particles settle in air so rapidly that few remain ouopendod 3. Schuster, H.H.: Pulmonary Aeboatosis In a bog. J. Path, /fbact. 31t Part 2, 751, 1931. 4. Vorrrald, A.J.j Variatlono in Individual Cuooeptlblllty to Industrial Dusts Inhaled into tho Lungs. Am. Hev. Tubero. 62 ID, 13, 1950. -6-