Department of Environmental Science & Engineering, Fudan University, Shanghai, 200032, PR China.
Department of Environmental Science & Engineering, Fudan University, Shanghai, 200032, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, PR China.
Environ Pollut. 2021 Jan 1;268(Pt B):115582. doi: 10.1016/j.envpol.2020.115582. Epub 2020 Sep 28.
Although it is known that increases in ambient particulate matter (PM) levels are associated with elevated occurrence of adverse health outcomes, the understanding of the mechanisms of PM-related health effects is limited by our knowledge of how particle size and composition are altered subsequent to inhalation through respiratory-deposited processing. Here we present a particle-generated hydroxyl radical (·OH) study of the size-resolved particles as particles are inhaled in the human respiratory tract (RT), and we show that accumulation-mode particles are significant factors (71-75%) in ·OH generation of lung-deposited particles using Multiple-Path Particle Dosimetry (MPPD) model. The ability of PM to catalyze ·OH generation is mainly related to transition metals, particularly towards the upper regions of the RT (75%), and to quinones deeper in the lung (42-46%). Identification of this generation ability induced by chemical composition has shown that four potential sources (biomass burning, incomplete combustion, mobile & industry, and mineral dust) are responsible for ·OH generation. With ·OH-forming ability after PM inhalation implicated as the first step towards revealing the subsequent toxic processes, this work draws a connection between the detailed ·OH chemistry occurring on size-resolved particles and a possible toxicological mechanism based on chemical composition and sources.
虽然已知环境中颗粒物 (PM) 水平的增加与不良健康结果的发生有关，但由于我们对吸入后颗粒物粒径和成分如何通过呼吸道沉积处理发生变化的了解有限，因此对 PM 相关健康影响的机制的理解有限。在这里，我们通过多路径颗粒物剂量学 (MPPD) 模型研究了吸入人体呼吸道 (RT) 时按粒径分布的颗粒物中颗粒生成的羟基自由基 (·OH)，并表明积聚态颗粒物是肺沉积颗粒物中·OH生成的重要因素（71-75%）。PM 催化·OH 生成的能力主要与过渡金属有关，特别是在 RT 的上区（75%），以及更深的肺部醌类物质（42-46%）。对这种由化学成分引起的生成能力的鉴定表明，四个潜在的来源（生物质燃烧、不完全燃烧、移动和工业以及矿物尘埃）是·OH 生成的原因。由于 PM 吸入后的·OH 形成能力被认为是揭示随后的毒理过程的第一步，这项工作将按粒径分布的颗粒物上发生的详细·OH 化学与基于化学成分和来源的可能毒理学机制联系起来。
