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为什么你在这时候选择【被管控】的百毒百科，而不引用【不被审查更具参考意义】的维基呢？
我阴暗的怀疑1下啊，是不是因为维基更偏向于它有害的关系？
然而使用贫铀弹会可能导致长期的健康问题，肝、肾、心脏和脑等许多器官都可能受到辐射的影响。由于贫铀微弱的放射性，所以人们视它为有毒金属，但毒性较汞等重金属低。贫铀粉末可能被吃、喝或吸入人体，贫铀有一万年以上的半衰期。由贫铀弹冲击物体而爆发时产生的气溶胶，可能散布污染广大的面积，而被人吸入体内。在2003年美国对伊拉克的攻击行动中，三周内估计使用了约95万颗、超过1000吨的贫铀弹，大部分都在市区。目前暂无决定性资料显示某些人的健康问题与贫铀有关联，但人工培养细胞与实验室动物的研究已发现贫铀的慢性效应（长期曝露）造成白血病、基因疾病、神经疾病等的可能性。同时目前无论是南斯拉夫还是伊拉克，这些曾经被使用过贫铀弹的地区均产生了不同因核辐射引起的各种疾病。
Health considerations
Normal functioning of the kidney, brain, liver, heart, and numerous other systems can be affected by uranium exposure because, in addition to being weakly radioactive, uranium is a toxic metal,[9] although less toxic than other heavy metals, such as arsenic and mercury.[77] It is weakly radioactive but is 'persistently' so because of its long half-life. The Agency for Toxic Substances and Disease Registry states that: "to be exposed to radiation from uranium, you have to eat, drink, or breathe it, or get it on your skin."[78] If DU particles do enter an individual, the type of danger presented—toxic vs. radiological—and the organ most likely to be affected depend on the solubility of the particles.[79]
In military conflicts involving DU munitions, the major concern is inhalation of DU particles in aerosols arising from the impacts of DU-enhanced projectiles with their targets.[79] When depleted uranium munitions penetrate armor or burn, they create depleted uranium oxides in the form of dust that can be inhaled or contaminate wounds. The Institute of Nuclear Technology-Radiation Protection of Attiki, Greece, has noted that "the aerosol produced during impact and combustion of depleted uranium munitions can potentially contaminate wide areas around the impact sites or can be inhaled by civilians and military personnel".[11] The utilisation of DU in incendiary ammunition is controversial because of potential adverse health effects and its release into the environment.[80][81][82][83][84][85]
The U.S. Department of Defense claims that no human cancer of any type has been seen as a result of exposure to either natural or depleted uranium.[86] Militaries have long had risk-reduction procedures for their troops to follow,[87] and studies are in consistent agreement that veterans who used DU-enhanced munitions have not suffered, so far, from an increased risk of cancer (see the Gulf War and Balkans sections below). The effects of DU on civilian populations are, however, a topic of intense and ongoing controversy.
As early as 1997, British Army doctors warned the Ministry of Defence that exposure to depleted uranium increased the risk of developing lung, lymph and brain cancer, and recommended a series of safety precautions.[88] According to a report issued summarizing the advice of the doctors, "Inhalation of insoluble uranium dioxide dust will lead to accumulation in the lungs with very slow clearance—if any. … Although chemical toxicity is low, there may be localised radiation damage of the lung leading to cancer." The report warns that "All personnel … should be aware that uranium dust inhalation carries a long-term risk … [the dust] has been shown to increase the risks of developing lung, lymph and brain cancers."[88] In 2003, the Royal Society called, again, for urgent attention to be paid to the possible health and environmental impact of depleted uranium, and added its backing to the United Nations Environment Programme's call for a scientific assessment of sites struck with depleted uranium.[89] In early 2004, the UK Pensions Appeal Tribunal Service attributed birth defect claims from a February 1991 Gulf War combat veteran to depleted uranium poisoning.[90][91] Also, a 2005 epidemiology review concluded: "In aggregate the human epidemiological evidence is consistent with increased risk of birth defects in offspring of persons exposed to DU."[12] Studies using cultured cells and laboratory rodents continue to suggest the possibility of leukemogenic, genetic, reproductive, and neurological effects from chronic exposure.[7]
Chemical toxicity
The chemical toxicity of depleted uranium is identical to that of natural uranium and about a million times greater in vivo than DU's radiological hazard,[92] with the kidney considered to be the main target organ.[93] Health effects of DU are determined by factors such as the extent of exposure and whether it was internal or external. Three main pathways exist by which internalization of uranium may occur: inhalation, ingestion, and embedded fragments or shrapnel contamination.[94] Properties such as phase (e.g. particulate or gaseous), oxidation state (e.g. metallic or ceramic), and the solubility of uranium and its compounds influence their absorption, distribution, translocation, elimination and the resulting toxicity. For example, metallic uranium is less toxic compared to hexavalent uranium(VI) uranyl compounds such as uranium trioxide.[95][96]
Uranium is pyrophoric when finely divided.[97] It will corrode under the influence of air and water producing insoluble uranium (IV) and soluble uranium (VI) salts. Soluble uranium salts are toxic. Uranium slowly accumulates in several organs, such as the liver, spleen, and kidneys. The World Health Organization has established a daily "tolerated intake" of soluble uranium salts for the general public of 0.5 µg/kg body weight, or 35 µg for a 70 kg adult.
Epidemiological studies and toxicological tests on laboratory animals point to it as being immunotoxic,[98] teratogenic,[99][100] neurotoxic,[101] with carcinogenic and leukemogenic potential.[102] A 2005 report by epidemiologists concluded: "the human epidemiological evidence is consistent with increased risk of birth defects in offspring of persons exposed to DU."[12]
Early studies of depleted uranium aerosol exposure assumed that uranium combustion product particles would quickly settle out of the air[103] and thus could not affect populations more than a few kilometers from target areas,[104] and that such particles, if inhaled, would remain undissolved in the lung for a great length of time and thus could be detected in urine.[105] Violently burning uranium droplets produce a gaseous vapor comprising about half of the uranium in their original mass.[106] Uranyl ion contamination in uranium oxides has been detected in the residue of DU munitions fires.[107][108]
Approximately 90 micrograms of natural uranium, on average, exist in the human body as a result of normal intake of water, food and air. Most is in the skeleton. The biochemistry of depleted uranium is the same as natural uranium.
Radiological hazards
The primary radiation danger from pure depleted uranium is due to alpha particles, which do not travel far through air, and do not penetrate clothing. However, in a matter of a month or so, a sample of pure depleted uranium will generate small amounts of thorium-234 and protactinium-234, which emit the more penetrating beta particles at almost the same rate as the uranium emits alpha rays. This is because uranium-238 decays directly to thorium-234, which with a half-life of 24 days decays to protactinium-234, which in turn decays in a matter of hours to the long-lived uranium-234. A quasi-steady state is therefore reached within a few multiples of 24 days.[109]
Available evidence suggests that the radiation risk is small relative to the chemical hazard.[92]
Surveying the veteran-related evidence pertaining to the Gulf War, a 2001 editorial in the BMJ concluded that it was not possible to justify claims of radiation-induced lung cancer and leukaemia in veterans of that conflict.[110] While agreeing with the editorial's conclusion, a reply noted that its finding in the negative was guaranteed, given that "global dose estimates or results of mathematical modelling are too inaccurate to be used as dose values for an individual veteran", and that, as of April 2001, no practical method of measuring the expected small doses that each individual veteran would receive had been suggested.[111] The author of the reply, a radiation scientist, went on to suggest a method that had been used several times before, including after the 1986 Chernobyl accident.[111] Despite the widespread use of DU in the Iraq War, at least a year after the conflict began, testing for UK troops was still only in the discussion phase.[112]
The Royal Society DU Working Group concluded in 2002 that there were "very low" health risks associated with the use of depleted uranium, though also ventured that, "in extreme conditions and under worst-case assumptions" lung and kidney damage could occur, and that in "worst-case scenarios high local levels of uranium could occur in food or water that could have adverse effects on the kidney".[113] In 2003, the Royal Society issued another urgent call to investigate the actual health and environmental impact of depleted uranium.[89] The same year, a cohort study of Gulf War veterans found no elevated risks of cancer generally, nor of any specific cancers in particular, though recommended follow up studies.[114]
According to the World Health Organization, a radiation dose from it would be about 60% of that from purified natural uranium with the same mass; the radiological dangers are lower due to its longer half-life and the removal of the more radioactive isotopes.
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楼主: fly1008
IP卡
狗仔卡
发表于 2019-5-3 20:14
显身卡
