Group of Mutagenesis, Department of Genetics and Microbiology, Faculty of Biosciences, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Spain.
Nanobiology Laboratory, Department of Natural and Exact Sciences, Pontificia Universidad Católica Madre y Maestra (PUCMM), Santiago de los Caballeros 51000, Dominican Republic.
Int J Mol Sci. 2022 Mar 9;23(6):2958. doi: 10.3390/ijms23062958.
The increasing accumulation of plastic waste and the widespread presence of its derivatives, micro- and nanoplastics (MNPLs), call for an urgent evaluation of their potential health risks. In the environment, MNPLs coexist with other known hazardous contaminants and, thus, an interesting question arises as to whether MNPLs can act as carriers of such pollutants, modulating their uptake and their harmful effects. In this context, we have examined the interaction and joint effects of two relevant water contaminants: arsenic and polystyrene nanoplastics (PSNPLs), the latter being a model of nanoplastics. Since both agents are persistent pollutants, their potential effects have been evaluated under a chronic exposure scenario and measuring different effect biomarkers involved in the cell transformation process. Mouse embryonic fibroblasts deficient for oxidative DNA damage repair mechanisms, and showing a cell transformation status, were used as a sensitive cell model. Such cells were exposed to PSNPLs, arsenic, and a combination PSNPLs/arsenic for 12 weeks. Interestingly, a physical interaction between both pollutants was demonstrated by using TEM/EDX methodologies. Results also indicate that the continuous co-exposure enhances the DNA damage and the aggressive features of the initially transformed phenotype. Remarkably, co-exposed cells present a higher proportion of spindle-like cells within the population, an increased capacity to grow independently of anchorage, as well as enhanced migrating and invading potential when compared to cells exposed to arsenic or PSNPLs alone. This study highlights the need for further studies exploring the long-term effects of contaminants of emerging concern, such as MNPLs, and the importance of considering the behavior of mixtures as part of the hazard and human risk assessment approaches.
塑料废物的不断积累和其衍生物微塑料和纳米塑料（MNPLs）的广泛存在，要求我们迫切评估它们的潜在健康风险。在环境中，MNPLs 与其他已知的有害污染物共存，因此，一个有趣的问题出现了，即 MNPLs 是否可以作为这些污染物的载体，调节它们的吸收和有害影响。在这种情况下，我们研究了两种相关水污染物：砷和聚苯乙烯纳米塑料（PSNPLs）的相互作用和联合效应，后者是纳米塑料的模型。由于这两种物质都是持久性污染物，因此在慢性暴露情况下评估了它们的潜在影响，并测量了参与细胞转化过程的不同效应生物标志物。缺乏氧化 DNA 损伤修复机制且表现出细胞转化状态的小鼠胚胎成纤维细胞被用作敏感的细胞模型。这些细胞被暴露于 PSNPLs、砷和 PSNPLs/砷的混合物中 12 周。有趣的是，通过使用 TEM/EDX 方法学证明了两种污染物之间存在物理相互作用。结果还表明，连续共暴露增强了 DNA 损伤和初始转化表型的侵袭性特征。值得注意的是，与单独暴露于砷或 PSNPLs 的细胞相比，共暴露细胞在群体中具有更高比例的类纺锤体细胞、独立于附着的生长能力以及增强的迁移和侵袭潜力。这项研究强调了需要进一步研究探索新兴关注污染物（如 MNPLs）的长期影响，以及考虑混合物行为作为危害和人类风险评估方法一部分的重要性。
