<\/p>\n
. . . verbatim excerpts from:<\/big><\/b><\/p>\n <\/p>\n <\/p>\n …\u00a0Inhalation is an important route by which nuclear workers and members of the nearby public may be exposed<\/span><\/b>\u00a0to airborne releases [of radioactivity]…. A major program was established at the Inhalation Toxicology Research Institute in 1960\u00a0to study the potential long-term health effects of inhaled … radionuclides using different species of laboratory animals<\/span><\/b>, primarily beagle dogs and rats….<\/span><\/p>\n This paper is directed primarily to results of experiments in which laboratory\u00a0animals were exposed once, briefly<\/span><\/b>, by inhalation or intravenous injection, to an individual … radionuclide….\u00a0The main long-term health effects were cancers<\/span><\/b>….<\/p>\n 3. Human Health Issues for Plutonium Inhalation: Since the first production of plutonium in the 1940s,\u00a0potential health effects from plutonium have been a concern for humans<\/span><\/b>.<\/p>\n The few people exposed to plutonium and the relatively small intakes that have occurred, at least in the Western world, have resulted in\u00a0very little direct information from human population studies<\/span><\/b>.<\/p>\n Due to the lack of human data until very recently, animal studies were conducted to provide information of the metabolism and toxicity of plutonium.<\/p>\n Early studies showed that plutonium is poorly absorbed from the gastrointestinal tract and through the intact skin. From these data,<\/p>\n were\u00a0clearly the most important exposure routes for potential human exposure<\/span><\/b>.<\/span><\/p>\n For this reason,\u00a0studies were initiated at the Lovelace Respiratory Research Institute on the toxicity of inhaled plutonium<\/span><\/b>. These studies were directed at several important health issues:<\/p>\n The early effects observed from the inhalation of high activity levels of plutonium<\/span><\/b>\u00a0were radiation pneumonitis, inflammation and scarring of the lung, and a decrease in the numbers of lymphocytes in the blood.<\/span><\/p>\n At lower activity levels and at much longer times after inhalation, lung cancer was the primary effect<\/span><\/b>\u00a0observed, especially from\u00a0239<\/small><\/sup>PuO2<\/small><\/sub>\u00a0[plutonium-239] ….<\/p>\n In these studies, the plutonium aerosols were delivered as monodisperse particles. That made it possible to alter the distribution of local dose within the lung\u00a0using many small particles or a few large particles<\/span><\/b>\u00a0[of plutonium].\u00a0Similar risks of developing lung cancer were found in both cases<\/span><\/b>….<\/p>\n Studies in multiple species — primarily dogs, rats, and mice — showed similar biological effects and cancer risks. This finding has provided\u00a0increased confidence in the extrapolation of the animal data<\/span><\/b>\u00a0[for the purpose of]\u00a0predicting health risks to people<\/span><\/b>.<\/p>\n The studies on the effect of age at the time of exposure are still in analysis, but early indications are that\u00a0old dogs may be more sensitive to plutonium dioxide than young adults and juveniles<\/span><\/b>. The old dogs developed lung injury at lower doses and shorter time intervals than the younger dogs….<\/p>\n A list of the publications that have been completed is available.<\/p>\n In summary,\u00a0inhaled plutonium dioxide was shown to cause serious biological effects in a dose-related fashion<\/span><\/b>\u00a0in the organs that received the largest doses….<\/p>\n The uniformity of dose distribution in the lung did not affect the probability of developing a cancer, and\u00a0the probability of developing lung cancer from inhaled\u00a0239<\/small><\/sup>PuO2<\/small><\/sub>\u00a0<\/span><\/b>[plutonium-239]\u00a0was similar among several laboratory animal species<\/span><\/b>. Age at exposure was important, and older animals were more sensitive for developing biological effects.<\/p>\n Based on the similar results obtained among laboratory animal studies,\u00a0extrapolation of these results to humans appears to be reasonable<\/span><\/b>.<\/p>\n <\/p>\n <\/p>\n [\u00a0How Much Plutonium is an Overdose?<\/a>\u00a0] Findings on the Toxicity of Plutonium . . . verbatim excerpts from: Lifetime Health Risks of Inhaled Radionuclides Insights from the Radiobiology Program at the Lovelace Respiratory Research Institute reprinted from the Transactions of the American Nuclear Society volume 77 (1997), pages 476-478 …\u00a0Inhalation is an important route by which nuclear workers …<\/p>\nLifetime Health Risks
\nof Inhaled Radionuclides<\/span><\/h2>\nInsights from the Radiobiology Program
\nat the Lovelace Respiratory Research Institute<\/span><\/h4>\n
\nreprinted from the
\nTransactions of the American Nuclear Society
\nvolume 77 (1997), pages 476-478<\/h5>\n
\n
\n\n
\nPerspectives from Laboratory Animal Studies<\/span><\/b>Bruce A. Muggenburg,
\nFletcher E Hahn,
\nRaymond A. Guilmette,
\nJoseph A. Diel,
\nBruce B. Boecker,
\nDavid L. Lundgren,
\nMark D. Hoover
\nof the Lovelace Respiratory Research Institute.<\/small><\/b><\/p>\n<\/blockquote>\nINTRODUCTION<\/b><\/span><\/h6>\n
\n
INFORMATION FROM STUDIES WITH LABORATORY ANIMALS<\/b><\/span><\/h6>\n
\n
\n
\n239<\/small><\/sup>PuO2<\/small><\/sub>\u00a0[plutonium-239] and\u00a0238<\/small><\/sup>PuO2<\/small><\/sub>\u00a0[plutonium-238];<\/li>\n
\ndistribution of dose within the lung;<\/li>\n
\ntoxicity of inhaled plutonium;<\/li>\n\n
See ”Publications of the ITRI
\nNuclear Toxicology Program: 1960-1996”
\nITRI-149, Inhalation Toxicology Research Institute,
\nLovelace Respiratory Research Institute (Dec. 1996).<\/span><\/h6>\n<\/blockquote>\nCONCLUSION<\/b><\/span><\/h6>\n
\n
\n[\u00a0Plutonium Sub-Directory<\/a> ]<\/p>\n","protected":false},"excerpt":{"rendered":"