The extensive development of nanotechnologies and nanomaterials poses a number of questions to toxicologists about the potential health risks of exposure to nanoparticles (NP). In this study, we analysed DNA damage in the leukocytes of 20 workers who were long-term exposed (18 ± 10 years) to NP in their working environment. Blood samples were collected in September 2016, before and after a shift, to assess (i) the chronic effects of NP on DNA (pre-shift samples) and (ii) the acute effects of exposure during the shift (the difference between pre- and post-shift samples). The samples from matched controls were taken in parallel with workers before the shift. Leukocytes were isolated from heparinised blood on a Ficoll gradient. The enzyme-modified comet assay (DNA formamido-pyrimidine-glycosylase and endonuclease III) demonstrated a considerable increase of both single- and double-strand breaks in DNA (DNA-SB) and oxidised bases when compared with the controls (2.4× and 2×, respectively). Acute exposure induced a further increase of DNA-SB. The welding and smelting of nanocomposites represented a higher genotoxic risk than milling and grinding of nanocomposite surfaces. Obesity appeared to be a factor contributing to an increased risk of oxidative damage to DNA. The data also indicated a higher susceptibility of males vs. females to NP exposure. The study was repeated in September 2017. The results exhibited similar trend, but the levels of DNA damage in the exposed subjects were lower compared to previous year. This was probably associated with lower exposure to NP in consequence of changes in nanomaterial composition and working operations. The further study involving also monitoring of personal exposures to NP is necessary to identify (i) the main aerosol components responsible for genotoxic effects in workers handling nanocomposites and (ii) the primary cause of gender differences in response to NP action.

中文翻译：

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处理纳米复合材料的工人在白细胞中的遗传毒性作用。

纳米技术和纳米材料的广泛发展向毒理学家提出了许多有关暴露于纳米颗粒（NP）的潜在健康风险的问题。在这项研究中，我们分析了20名长期暴露于NP（18±10年）的工人在其工作环境中的白细胞中的DNA损伤。于轮班前后，于2016年9月采集血液样本，以评估（i）NP对DNA的慢性影响（轮班前样品）和（ii）轮班期间暴露的急性影响（前轮班之间的差异）。和移位后的样本）。在轮班之前，与工人平行地从匹配的对照中取样。从肝素化的血液中按Ficoll梯度分离白细胞。酶修饰的彗星试验（DNA甲酰胺基-嘧啶-糖基化酶和核酸内切酶III）表明，与对照（2.4x和2）相比，DNA（DNA-SB）和氧化碱基的单链和双链断裂均显着增加。 ×）。急性接触引起DNA-SB进一步增加。与研磨和研磨纳米复合材料表面相比，纳米复合材料的焊接和熔炼具有更高的遗传毒性风险。肥胖似乎是导致DNA氧化损伤风险增加的因素。数据还表明，男性和女性对NP暴露的敏感性更高。该研究于2017年9月重复进行。结果显示出相似的趋势，但暴露受试者的DNA损伤水平低于去年。由于纳米材料成分和工作操作的变化，这可能与较低的NP暴露量有关。为了确定（i）负责处理纳米复合材料的工人的遗传毒性作用的主要气溶胶成分和（ii）响应NP作用的性别差异的主要原因，还需要进行进一步的研究，包括监测个人对NP的暴露。