贫铀弹伤害及其医学防护

贫铀在军事上主要用于加固装甲和制造贫铀弹。贫铀武器多次在实战中被使用,造成人员死伤,装备破坏,环境污染,产生了严重后果。本从贫铀弹的4种杀伤因素、贫铀弹伤害的主要临床病理特点、医学防护和救治几个方面阐述了贫铀弹所致的伤害及其医学防护,同时也对防护中几个基本问题提出了自己的看法。     

长期接触贫铀对大鼠遗传毒性的初步研究

目的研究贫铀植入/摄入3个月后对大鼠的毒性作用.方法观察大鼠精子畸形率,骨髓微核率的改变,睾丸的超微结构和病理形态学改变以及采用显性致死突变试验观察贫铀对大鼠的生殖毒性.结果植入/摄入贫铀后大鼠精子畸形率和微核率均有增加,睾丸超微结构均有不同程度的改变,而病理形态学观察则未见显著影响.植入组大鼠受孕率明显低于对照组.结论贫铀长时间暴露可对大鼠产生生殖毒性损害以及超微结构的损伤.     

贫铀对细胞存活的影响及基因突变作用

目的：研究贫铀（DU）对细胞存活的影响和诱发基因突变的作用，并初步探讨其可能的机制。方法：用包含单条人类11号染色体（Hchr11）的人－中国仓鼠卵巢杂交细胞（AL细胞）为靶, 观察DU作用细胞的低密度接种效率；用CD59表面抗原抗体及其补体筛选突变细胞克隆，研究DU诱发的Hchr11基因突变率。结果：DU可明显降低细胞存活率，并使Hchr11基因突变率显著增高；二甲基亚砜（DMSO)、Ca^2 和Na2SeO3对DU诱发的细胞增殖死亡和基因突变有较好的保护效果。结论：DU对细胞 存活的影响和基因突变作用可能与其诱发产生活性氧自由基及其与Ca^2 的交换有关。     

气管灌注贫铀染毒对大鼠免疫功能的影响

目的 研究气管灌注贫铀染毒对大鼠免疫功能的影响。方法 大鼠气管单次灌注不同剂量的贫铀粉尘后，每周称体重，定期测定外周血细胞参数，活杀后分别测定免疫器官重量系数、脾细胞抗体生成细胞数、胸腺淋巴细胞及其分类细胞数。结果 气管灌注贫铀染毒后早期，大鼠体重减少，白细胞增高，红细胞、血小板降低，所有变化不同程度地存在剂量依赖关系，且在1～2个月内恢复到正常水平。脾和胸腺细胞的免疫功能均观察到剂量依赖性的异常改变。结论 气管灌注贫铀染毒对大鼠免疫功能有损伤作用。     

铀尾矿库周边农产品中镭-226及铀浓度调查分析

目的 对某退役铀尾矿库周边主要农产品中的放射性核素镭-226和天然铀含量进行调查,以了解尾矿库周边食品中的放射性水平。方法 2017—2021年在该尾矿库周边地区连续5年采集多份大米和豆角样品,用高纯锗γ谱仪检测镭-226和天然铀浓度,并运用间接法对当地标准人食入镭-226所致内照射年待积有效剂量进行估算。结果 大米中天然铀的检出率为96.0%,镭-226的检出率为74.0%;豆角中天然铀的检出率为96.7%,镭-226的检出率为73.3%,周围居民食入镭-226所致年待积有效剂量约为170.22 μSv/a。结论 尾矿库周边主要农产品中镭-226和天然铀浓度均在国家标准限值以内,通过与国内相关领域内的研究结果对比,尾矿库周围居民食入镭-226所致辐射影响是可接受的。     

Hydrogen sulfide alleviates uranium‐induced acute hepatotoxicity in rats: Role of antioxidant and antiapoptotic signaling

As an endogenous gaseous mediator, H₂S exerts antioxidative, antiapoptotic, and cytoprotective effects in livers. This study was designed to investigate the protective role of H₂S against uranium‐induced hepatotoxicity in adult SD male rats after in vivo effect of uranium on endogenous H₂S production was determined in livers. The levels of endogenous H₂S and H₂S‐producing enzymes (CBS and CSE) were measured in liver homogenates from uranium ‐intoxicated rats. In rats injected intraperitoneally (i.p.) with uranyl acetate or NaHS (an H₂S donor) alone or in combination, we examined biochemical parameters to assess liver function, revealed hepatic histopathological alteration, investigated oxidative stress markers, and explored apoptotic signaling in liver homogenates. The results suggest that uranium‐intoxication in rats decreased CBS and CSE protein expression, H₂S synthesis capacity, and endogenous H₂S generation. NaHS administration in uranium‐intoxicated rats produced amelioration in liver biochemical indices and histopathological effects, decreased MDA content, and increased GSH level and antioxidative enzymes activities like SOD, CAT, GPx, and GST. NaHS administration in uranium‐intoxicated rats attenuated uranium‐activated phosphorylation state of JNK. NaHS treatment in uranium‐intoxicated rats increased antiapoptotic Bcl‐2 but decreased pro‐apoptotic Bax, resulting in the rise of Bcl‐2/Bax ratio. NaHS treatment in uranium‐intoxicated rats reduced the apoptosis mediator caspase‐3 and cytochrome c release and elevated ATP contents. Taken together, these data implicate that H₂S can afford protection to rat livers against uranium‐induced adverse effects mediated by up‐regulation of antioxidant and antiapoptotic signaling. The anti‐apoptotic property of H₂S may be involved, at least in part, in inhibiting JNK signaling. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 581–593, 2017.     

Allergic contact dermatitis due to nonylphenol ethoxylate (nonoxynol-6)

The non-ionic emulsifier "nonoxynol-6" found in an industrial waterless hand cleanser induced allergic contact dermatitis on the upper extremities of a uranium mill maintenance worker. The chemical is an irritant for the rabbit. It was not shown to be a cutaneous sensitizer for the albino guinea pit using the guinea pig maximization test.     

贫铀气溶胶在土壤中迁移深度的研究

目的研究酸雨对贫铀在土壤中迁移深度的影响及贫铀在我国6类代表土壤中的迁移规律，并探讨贫铀在土壤中迁移时对地下水的影响。方法利用建立的贫铀在土壤中迁移的实验室模拟模型和电感耦合等离子体质谱技术，测定不同深度土层的铀浓度、^235U／^238U比值，以及淋洗液中的铀浓度，确定贫铀的迁移深度及其迁移对地下水可能造成的影响。结果在pH3．0的模拟酸雨的淋洗下，贫铀气溶胶在洗土和褐土中的迁移深度分别是6～8cm和4～6cm，并且随着淋洗液的酸度增加，贫铀在土壤中的迁移加深；贫铀在我国主要的6类土壤中的迁移深度介于0～4cm之间；贫铀在淋洗液和土壤中的分配系数小于0．004，淋洗液中的铀浓度为0．05～10．33μg/L。结论实验证明酸雨可以促进贫铀在土壤中的迁移。沉降在土壤表面的贫铀绝大部分停留在土壤表层中，对土壤造成长期污染，但对地下水造成影响的可能性较小。贫铀的迁移能力与土壤中的有机物含量有关。     

Biological Monitoring for Depleted Uranium Exposure in U.S. Veterans

Background

As part of an ongoing medical surveillance program for U.S. veterans exposed to depleted uranium (DU), biological monitoring of urine uranium (U) concentrations is offered to any veteran of the Gulf War and those serving in more recent conflicts (post-Gulf War veterans).

Objectives

Since a previous report of surveillance findings in 2004, an improved methodology for determination of the isotopic ratio of U in urine (²³⁵U:²³⁸U) has been developed and allows for more definitive evaluation of DU exposure. This report updates previous findings.

Methods

Veterans provide a 24-hr urine specimen and complete a DU exposure questionnaire. Specimens are sent to the Baltimore Veterans Affairs Medical Center for processing. Uranium concentration and isotopic ratio are measured using ICP-MS at the Armed Forces Institute of Pathology.

Results

Between January 2003 and June 2008, we received 1,769 urine specimens for U analysis. The mean urine U measure was 0.009 μg U/g creatinine. Mean urine U concentrations for Gulf War and post-Gulf War veterans were 0.008 and 0.009 μg U/g creatinine, respectively. Only 3 of the 1,700 (0.01%) specimens for which we completed isotopic determination showed evidence of DU. Exposure histories confirmed that these three individuals had been involved in “friendly fire” incidents involving DU munitions or armored vehicles.

Conclusions

No urine U measure with a “depleted” isotopic signature has been detected in U.S. veterans without a history of retained DU embedded fragments from previous injury. These findings suggest that future DU-related health harm is unlikely in veterans without DU fragments.