Liu Qingyang, Zhang Yuanxun, Liu Yanju, Zhang Meigen
College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 100049, China,
Environ Sci Pollut Res Int. 2014;21(15):9325-33. doi: 10.1007/s11356-014-2843-6. Epub 2014 Apr 15.
Epidemiologic studies have suggested that particulate matter (PM)-associated adverse health effects are related to particle composition. To study the toxicological characteristics of dust storm, airborne PM10 was collected at two sites in Beijing from March to May 2012. The production of reactive oxygen species (ROS), quantified by dithiothreitol (DTT), was used to measure the PM-induced oxidative potential. Two dust storm (DS) samples were monitored during the sampling period: one happened on March 28th (DS1) and the other one was on April 28th (DS2). The backward trajectory results showed that both events originated from Inner Mongolia and Mongolia, respectively. The increased trends of ROS activities during the dust storm episode in PM10 were observed for all the dust storms owing to a higher concentration of water-soluble components for all the PM10 samples compared to nondust storm ones. Interestingly, the correlations between DTT consumption with water-soluble species yield interesting results about the spatial variability of redox activity between sites. In particular, a tracer of soil suspension, namely Fe, contributed the most fraction to ROS variability in the urban background site. Water-soluble organic carbon (WSOC) made the highest contribution to ROS variability, suggesting that vehicle emission might be important driving factors of the PM-induced oxidative stress in the urban site.
流行病学研究表明，与颗粒物（PM）相关的不良健康影响与颗粒成分有关。为了研究沙尘暴的毒理学特征，于2012年3月至5月在北京的两个地点采集了空气中的PM10。用二硫苏糖醇（DTT）定量的活性氧（ROS）生成量来测量PM诱导的氧化潜力。在采样期间监测到两次沙尘暴（DS）样本：一次发生在3月28日（DS1），另一次在4月28日（DS2）。后向轨迹结果表明，这两次事件分别起源于内蒙古和蒙古国。由于所有PM10样本中水溶性成分的浓度高于非沙尘暴样本，在所有沙尘暴期间，PM10中ROS活性均呈现增加趋势。有趣的是，DTT消耗量与水溶性物质之间的相关性得出了关于各站点之间氧化还原活性空间变异性的有趣结果。特别是，土壤悬浮物的一种示踪剂，即铁，在城市背景站点对ROS变异性的贡献最大。水溶性有机碳（WSOC）对ROS变异性的贡献最大，这表明车辆排放可能是城市站点PM诱导氧化应激的重要驱动因素。
