Zhang Yongqiang, Zhou Yousong, Wang Hanchen, Xiao Kai, Luo Zhihan, Li Yaojie, Xing Ran, Jiang Ke, Fu Donglei, Liu Wenxin, Tao Shu, Shen Guofeng
Laboratory for Earth Surface Process, College of Urban and Environmental Sciences, Peking University, 100871, Beijing, China.
College of Life and Environmental Sciences, Minzu University of China, Beijing, 100081, China.
Environ Res. 2024 Dec 1;262(Pt 1):119853. doi: 10.1016/j.envres.2024.119853. Epub 2024 Aug 31.
Environmental persistent free radicals (EPFRs), as emerging contaminants in environment, can induce oxidative stress causing severe adverse health outcomes. The formation of EPFRs is thought to be associated with the transformation of aromatic compounds like polycyclic aromatic hydrocarbons (PAHs). Herein this study firstly evaluated EPFRs in industrial soils being highly polluted by PAHs, and explored its associated with PAHs, with the modification of soil organic matter content. Soil EPFRs from two industrial plants were 4.1 × 10 and 4.5 × 10 spins/g, respectively, that were significantly higher than the levels in the surrounding areas. Carbon-centered EPFRs account for approximately 80% inside the plant, but outside the plants, nearly 50-70% of EPFRs were carbon-centered with adjacent heteroatoms. As one important precursor of EPFRs, PAHs exhibited a significantly positive correlation with EPFRs in industrial soils (p < 0.05), explaining 40%-60% of the variation in EPFRs concentration in the present study. The relationship between soil organic matter and EPFRs concentration normalized by PAHs forms an inverted V-shape, suggesting an inhibition effect of soil organic matter on the EPFR formation potentials from PAHs, that is worthy to be further examed in future laboratory and field experiments.
环境持久性自由基（EPFRs）作为环境中的新兴污染物，可引发氧化应激，导致严重的不良健康后果。EPFRs的形成被认为与多环芳烃（PAHs）等芳香族化合物的转化有关。在此项研究中，首先评估了受PAHs高度污染的工业土壤中的EPFRs，并探讨了其与PAHs的关系以及土壤有机质含量的变化。来自两个工厂的土壤EPFRs分别为4.1×10和4.5×10自旋/g，显著高于周边地区的水平。以碳为中心的EPFRs在工厂内部约占80%，但在工厂外部，近50%-70%的EPFRs是以与相邻杂原子相连的碳为中心。作为EPFRs的一个重要前体，PAHs与工业土壤中的EPFRs呈现出显著的正相关（p<0.05），在本研究中解释了EPFRs浓度变化的40%-60%。土壤有机质与经PAHs归一化后的EPFRs浓度之间的关系呈倒V形，表明土壤有机质对PAHs形成EPFRs的潜在抑制作用，这值得在未来的实验室和野外实验中进一步研究。
