SKL-ESPC, College of Environmental Sciences and Engineering, Peking University, Beijing, 100871, China.
Environment Research Institute, Shandong University, Qingdao, 266237, China.
Environ Res. 2022 Sep;212(Pt D):113499. doi: 10.1016/j.envres.2022.113499. Epub 2022 May 23.
Particulate matter (PM) has been considered to be closely related to human health, especially fine particulate matter. However, whether PM mass concentration alone is a good indicator for health impact remains a challenging question. In this study, emissions from residential coal combustion (RCC), one of the important PM sources in northern China, were tested to examine the relationship between the emission factors of particle-generated reactive oxygen species (ROS) (EF) and PM (EF). A total of 24 combinations of source tests were conducted, including eight types of coal with different geological maturities (two anthracites and six bituminous) burned in three types of stoves (one honeycomb coal stove, one old chunk stove, and one new chunk stove). Here, ROS was defined as generated hydroxyl radical (·OH) by PM, and results showed EF from 24 residential coal combustion varied greatly by nearly 20 times. EF ranged 0.78-14.85 and 2.99-12.91 mg kg for the emissions from honeycomb and chunk coals, respectively. Moreover, the correlation between EF and EF was significantly positive in honeycomb coal emissions (r = 0.82, p < 0.05), but it was insignificant in chunk coal emissions (r = 0.07, p > 0.05). For honeycomb coal emissions, organic carbon (OC) was quite abundant in PM and it might be the predominant contributor to both EF and EF, resulting in a strong and positive correlation. For chunk coal emissions, high EF was mainly related to relatively high metal emissions in AN and LVB, while the metals were not major components in PM, leading to a poor correlation between EF and EF. Therefore, this study revealed that PM was not always positively correlated with ROS from residential coal burning, and the relationship was mainly determined by the compositions of PM, suggesting PM mass concentration alone may not be the best indicator for assessing health impacts.
颗粒物 (PM) 被认为与人类健康密切相关，尤其是细颗粒物。然而，PM 质量浓度本身是否是健康影响的良好指标仍然是一个具有挑战性的问题。在这项研究中，测试了来自中国北方的重要 PM 来源之一——居民燃煤的排放物，以检验颗粒生成的活性氧物质 (ROS) 排放因子 (EF) 与 PM 排放因子 (EF) 之间的关系。进行了总共 24 种源测试组合，包括 8 种不同地质成熟度的煤 (两种无烟煤和 6 种烟煤)，在 3 种炉具中燃烧 (一种蜂窝煤炉、一种旧块煤炉和一种新块煤炉)。在这里，ROS 被定义为 PM 产生的羟基自由基 (·OH)，结果表明，24 种居民燃煤的 EF 变化幅度很大，近 20 倍。蜂窝煤和块煤的 EF 分别为 0.78-14.85 和 2.99-12.91mgkg。此外，在蜂窝煤排放物中，EF 与 EF 之间的相关性呈显著正相关 (r=0.82，p<0.05)，但在块煤排放物中不显著 (r=0.07，p>0.05)。对于蜂窝煤排放物，PM 中含有丰富的有机碳 (OC)，它可能是 EF 和 EF 的主要贡献者，导致两者之间存在强烈的正相关关系。对于块煤排放物，EF 较高主要与 AN 和 LVB 中相对较高的金属排放有关，而金属不是 PM 的主要成分，导致 EF 与 EF 之间相关性较差。因此，本研究表明，居民燃煤产生的 PM 并不总是与 ROS 呈正相关，这种关系主要取决于 PM 的成分，表明 PM 质量浓度本身可能不是评估健康影响的最佳指标。
