State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China.
State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China.
Chemosphere. 2017 Aug;181:360-367. doi: 10.1016/j.chemosphere.2017.04.098. Epub 2017 Apr 22.
Pine needle samples were collected near a municipal solid waste incinerator (MSWI) in Pearl River Delta, southern China, as well as the stack gas and dust samples of the MSWI were simultaneously collected. Polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) were analyzed following the USEPA Method 1613B. The concentration of PCDD/Fs in the pine needles (137-625 ng/kg, 25-51 ng I-TEQ/kg) is the highest level ever detected in China. Congener profile comparison and principal component analysis (PCA) confirmed the MSWI as an important emission source of environmental PCDD/Fs. The PCDD/Fs in the pine needles mainly depended on the atmospheric concentration, exposure time and also the wind direction. The accumulation of PCDD/Fs in this species did not occur at a steady rate, and the total concentrations covered up the actual photolysis information. Gas-phase partitioning of compounds in the atmosphere was the dominant process through which PCDD/Fs were adsorbed onto the pine needle surface in contrast with particle-phase deposition, and subsequent environmental behavior varied between the congeners. Photo-degradation was the major transformation process as PCDD/Fs were adsorbed onto the pine needle surfaces. Higher chlorinated PCDD/Fs were more recalcitrant to photo-degradation than those that were less chlorinated, and PCDDs were more resistant to photo-degradation than PCDFs. On the other hand, the strong ability of lipid-rich pine needles to accumulate dioxin compounds indicates they can be used as the absorption sink of PCDD/Fs in heavily polluted areas because it is easier to dispose of pine needles than it is to clean contaminated air.
在中国珠江三角洲的一个城市固体废物焚烧厂（MSWI）附近采集了松针样本，同时采集了 MSWI 的烟道气和粉尘样本。采用美国环保署方法 1613B 对多氯二苯并对二恶英和多氯二苯并呋喃（PCDD/Fs）进行了分析。松针中的 PCDD/Fs 浓度（137-625ng/kg，25-51ng I-TEQ/kg）是中国有记录以来的最高水平。同系物特征比较和主成分分析（PCA）证实 MSWI 是环境 PCDD/Fs 的一个重要排放源。松针中的 PCDD/Fs 主要取决于大气浓度、暴露时间和风向。PCDD/Fs 在该物种中的积累不是以稳定的速率发生的，总浓度掩盖了实际的光解信息。化合物在大气中的气相分配是 PCDD/Fs 被吸附到松针表面的主要过程，而与颗粒相沉积相反，随后的环境行为在同系物之间有所不同。与颗粒相沉积相反，化合物在大气中的气相分配是 PCDD/Fs 被吸附到松针表面的主要过程。与低氯取代的 PCDD/Fs 相比，高氯取代的 PCDD/Fs 更不易发生光降解，而 PCDDs 比 PCDFs 更不易发生光降解。另一方面，富含脂质的松针具有很强的吸附二恶英化合物的能力，这表明它们可以作为重污染地区 PCDD/Fs 的吸收汇，因为处理松针比清洁受污染的空气更容易。
