An assessment of immediate DNA damage to occupationally exposed workers to low dose ionizing radiation by using the comet assay.
An assessment of immediate DNA damage to occupationally exposed workers to low dose ionizing radiation by using the comet assay.
复制标题
使用彗星测定评估因职业暴露于低剂量电离辐射的工人的直接 DNA 损伤。
DOI：
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发表时间：
2010
期刊：
影响因子：
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通讯作者：
S. Frías
中科院分区：
文献类型：
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作者：
A. Martinez;M. Coleman;C. Romero;S. Frías
背景
几项细胞遗传学研究表明，受低剂量电离辐射照射的工作人员染色体畸变频率增加，但各工作领域的剂量、辐射类型和管理各不相同;这种差异可能会产生不同数量的DNA损伤，在人员受照射后的最初几个小时内即可检测到。在这项研究中，我们评估了41名来自放射科、核医学科和放射治疗科的工作人员和20名来自同一机构的健康未受照者因暴露于低剂量电离辐射而引起的早期DNA损伤。
材料和方法
从暴露和未暴露的受试者中采集血样，使用彗星试验分析DNA损伤。比较了工作日前后以及各组之间彗星尾部的迁移情况;并得出了DNA迁移与当月暴露剂量的关系。
结果
职业接触组DNA损伤程度在工作日后明显高于工作日前和非接触组（P < 0.01）。放射性月剂量与工作日前后DNA迁移长度呈正相关（P < 0.01）。不同科室工作人员的彗星尾长度有显著性差异：放射科（28.6 μ m）较核医学科（92.5 μ m）和放射治疗科（63.4 μ m）的DNA损伤小。
结论
所有职业暴露的工人在工作日之后都表现出DNA片段化的增加。所有三个服务的辐射量是不同的，在核医学和放射治疗的工作人员显示出更大的每月剂量的暴露和更大的DNA损伤比放射工作人员。在使用放射性核素的核医学中观察到较长的尾部;这些放射性物质由工作人员经口或静脉处理和给予患者，这意味着不同类型的暴露和辐射，这可能解释了本研究中发现的差异。彗星试验检测到的大部分DNA损伤都得到了修复，但其中一部分可能导致稳定的染色体重排，这可能会带来长期的健康风险。重要的是要使受照工作人员认识到他们在放射工作中的责任，并改进医院的安全措施。
BACKGROUND
Several cytogenetic studies have shown an increased frequency of chromosomal aberrations for workers exposed to low dose ionizing radiation, however the dose, type of radiation and management vary among the areas of work; it is possible that this variation may generate different quantity of DNA damage, detectable within the first hours after exposure of the personnel. In this study we assessed early DNA lesions caused by exposure to low doses of ionizing radiation in 41 workers from the departments of Radiology, Nuclear Medicine and Radiotherapy and a group of 20 healthy unexposed individuals, all from the same Institution.
MATERIAL AND METHODS
Blood samples were obtained from exposed and unexposed subjects for analysis of DNA damage using the comet assay. The migration of the comet's tail was compared before and after the workday, as well as among the groups; the relationship between DNA migration and the exposure dose of the month was also obtained.
RESULTS
A significant increase in damage to DNA was seen after workday for the occupationally exposed group (p < 0.01) as compared with the samples before workday as well as with those from the unexposed group. A positive correlation was found between the monthly dose of radiation and the migration length of DNA before and after the workday (p < 0.01). There were significant differences in the length of the comet tails among workers from different departments: workers from Radiology (28.6 microm) have less DNA damage than those from Nuclear Medicine and Radiotherapy (92.5 microm, 63.4 microm respectively) departments.
CONCLUSIONS
All the workers occupationally exposed showed an increase in DNA fragmentation after the workday. The amount of radiation in all three services is different, in Nuclear Medicine and Radiotherapy the workers showed a greater monthly dose of exposure and greater DNA damage than the Radiology workers. The longer tails were observed in Nuclear Medicine where radionuclides are used; these radioactive substances are handled and administered to patients orally or intravenously by the workers, which implies a different type of exposure and radiation, this may explain the differences found in this study. Most of the DNA damage detected by the comet assay is repaired, however a part of it may result in stable chromosomal rearrangements that may represent a long-term health risk. It is important to sensitize exposed workers on their responsibility of working with radiation and the improvement of the hospital safety practices.