title: An autoradiographic search for radioactive particles in the lungs of cigarette smokers.
abstract: Mucosal samples from the bifuracation of a major bronchus were examined from 23 patients undergoing diagnostic bronchoscopy. Samples were autoradiographed using a technique that avoids any contact between tissue and reagents until the end of autoradiographic exposure. The autoradiographs were scanned for a-particle tracks. No significant level of alpha -activity was detected, even in samples from heavy smokers who had continued to smoke within several hours of the bronchoscopy. The lower limit of detection of a-activity in this experiment was equivalent to about 55.5 becquerrels/kg (1,500 pCi/kg) Polonium-210. These results do not support the hypothesis presented by others that a radioactivity in particulate material of cigarette smoke contributes significantly to the association between cigarette-smoking and bronchial carcinoma.
mesh_terms: D000328:Adult; D000368:Aged; D000512:Alpha Particles; D000818:Animals; D001345:Autoradiography; D001980:Bronchi / Q000032:analysis; D005260:Female; D006801:Humans; D008168:Lung / Q000032:analysis*; D008297:Male; D051379:Mice; D008875:Middle Aged; D009092:Mucous Membrane / Q000032:analysis; D011868:Radioisotopes / Q000032:analysis; D012907:Smoking / Q000378:metabolism*
chemical_list: D011868:Radioisotopes