Yunnan Provincial Key Laboratory of Soil Carbon Sequestration and Pollution Control, Faculty of Environmental Science & Engineering, Kunming University of Science & Technology, Kunming, 650500, China.
Yunnan Provincial Key Laboratory of Soil Carbon Sequestration and Pollution Control, Faculty of Environmental Science & Engineering, Kunming University of Science & Technology, Kunming, 650500, China.
Sci Total Environ. 2022 Sep 15;839:156226. doi: 10.1016/j.scitotenv.2022.156226. Epub 2022 May 26.
Environmentally persistent free radicals (EPFRs) have attracted extensive attention due to their potential toxicity. However, EPFRs-containing particles always coexist with their parent organic contaminants and intermediate degradation products (IM), which may have hindered the toxicity assessment of EPFRs. In this study, the toxicity of EFFRs was specifically verified after comparing the systems without EPFRs, such as the immediate mixture of catechol (CT) and particles, solutions of CT only, IM extracted from the particles, as well as particles after EPFRs quenching. Caenorhabditis elegans (C. elegans) were used as model organisms. Our results showed that EPFRs-containing particles (Si-Al-CT) exhibited significant toxicity to C. elegans, but not for the parent chemical CT and IM on the particles. Higher levels of reactive oxygen species (ROS) and malondialdehyde (MDA) in the Si-Al-CT system were attributed to the mediated generation of ·O and ·OH via EPFRs. EPFRs could increase gene expressions related not only to oxidative stress and biotransformation in C. elegans, but also to indications of disturbances in energy homeostasis, survival, proliferation, cell and embryonic development. Overall, these results confirmed the direct toxicity of EPFRs and highlighted the key role of EPFRs which may be neglected in assessing the environmental risks of organic contaminants.
环境持久性自由基（EPFRs）因其潜在毒性而引起了广泛关注。然而，含 EPFRs 的颗粒总是与它们的母体有机污染物和中间降解产物（IM）共存，这可能阻碍了对 EPFRs 的毒性评估。在这项研究中，通过比较不含 EPFRs 的系统，如儿茶酚（CT）和颗粒的即时混合物、仅 CT 的溶液、从颗粒中提取的 IM 以及 EPFRs 淬灭后的颗粒，专门验证了 EPFRs 的毒性。秀丽隐杆线虫（C. elegans）被用作模型生物。我们的结果表明，含 EPFRs 的颗粒（Si-Al-CT）对 C. elegans 表现出显著的毒性，但对母体化学 CT 和颗粒上的 IM 没有毒性。Si-Al-CT 系统中活性氧（ROS）和丙二醛（MDA）水平较高，这归因于 EPFRs 通过介导生成·O 和·OH。EPFRs 不仅可以增加与秀丽隐杆线虫氧化应激和生物转化相关的基因表达，还可以增加能量稳态、生存、增殖、细胞和胚胎发育紊乱的迹象。总的来说，这些结果证实了 EPFRs 的直接毒性，并强调了在评估有机污染物的环境风险时可能被忽视的 EPFRs 的关键作用。
