Atmospheric aging modifies the redox potential and toxicity of humic-like substances (HULIS) from biomass burning
Atmospheric aging modifies the redox potential and toxicity of humic-like substances (HULIS) from biomass burning
复制标题
大气老化改变了生物质燃烧中腐殖质类物质 (HULIS) 的氧化还原电位和毒性
DOI：
10.1039/d3ea00104k
复制
发表时间：
2023
期刊：
影响因子：
--
通讯作者：
Rudich, Yinon
中科院分区：
文献类型：
--
作者：
Li, Chunlin;Calderon-Arrieta, Diego;Pardo, Michal;Cai, Dongmei;Laskin, Alexander;Chen, Jianmin;Rudich, Yinon
本研究研究了木材阴燃排放的HULIS在大气和中性肺液中的反应所引起的氧化还原电位和毒理学变化。新鲜的HULIS气雾剂表现出显著的氧化潜力(OP)和抗氧化能力(AOC)。夜间通过非均相臭氧或硝酸根的氧化反应对HULIS OP和AOC的影响不同，高湿度促进了HULIS对臭氧的吸收和HULIS的氧化，导致它们的氧化还原电位显著降低。臭氧氧化还原活性成分(RAC)的有效速率常数随RH增大而增大，抗氧化组分的有效速率常数为(3.2~12.7)×10−18，氧化组分的有效速率常数为(1.8~9.7)×10−18cm3mol−1 S−1。相应的反应速率常数分别为1.2×10−14和3.9×10−15cm3ol−1 S−1。肺上皮细胞的细胞毒性与OP的变化有很好的相关性，提示OP是反映HULIS氧化毒性的良好指标。新鲜和大气老化的HULIS在中性肺液模拟物中的氧化还原反应降低了它们的OP和AOC，并伴随着过氧化氢的产生。HULIS的过氧化氢产生量由OP和AOC共同决定，肺液抗氧化剂的加入增加了过氧化氢的产生量。大气老化延缓了氧化还原电位的衰减，减少了过氧化氢的产生，表明老化的HULIS中剩余的RAC对肺液环境中的固有反应具有相对较长的寿命。这项研究强调，在评估HULIS和相关有机气雾剂对健康的影响时，需要考虑大气变化和肺液水反应。
This study investigated the redox potential and toxicological changes of wood smoldering emitted HULIS due to reactions in the atmosphere and in neutral lung fluids. Fresh HULIS aerosols exhibited substantial oxidative potential (OP) and antioxidant capacity (AOC). Nighttime oxidation via heterogeneous O3 or NO3˙ reactions impacted HULIS OP and AOC differently, with high humidity enhancing O3 uptake and HULIS oxidation, causing a significant reduction in their redox potentials. The effective rate constants for HULIS redox-active components (RACs) by O3 reaction increased with RH (<1.5% to 75%), with values of (3.2–12.7)×10−18 and (1.8–9.7)×10−18 cm3 mol−1 s−1 for antioxidant moieties and oxidant components, respectively. The corresponding rate constants for NO3˙ reactions were 1.2 × 10−14 and 3.9 × 10−15 cm3 mol−1 s−1. The endpoint cytotoxicity of HULIS, studied with lung epithelial cells, correlated well with the changes in OP, suggesting OP as a good indicator of HULIS oxidative toxicity. Redox reactions of fresh and atmospherically aged HULIS in neutral lung fluid mimics decreased their OP and AOC accompanied by H2O2 generation. The H2O2 yields were determined by both OP and AOC of HULIS, and the addition of lung fluid antioxidants amplified the H2O2 yield. Atmospheric aging retarded the decay of the redox potential and abated H2O2 yield, demonstrating that the remaining RACs in aged HULIS have relatively longer lifetimes against intrinsic reactions in the lung fluid environment. This study underscores the need to consider atmospheric transformations and lung fluid aqueous reactions when evaluating the health impact of HULIS and related organic aerosols.