Han Y M, Bandowe B A M, Wei C, Cao J J, Wilcke W, Wang G H, Ni H Y, Jin Z D, An Z S, Yan B Z
Key Lab of Aerosol Science & Technology, SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710075, China.
Geographic Institute, University of Berne, Hallerstrasse 12, 3012 Berne, Switzerland.
Chemosphere. 2015 Jan;119:1335-1345. doi: 10.1016/j.chemosphere.2014.02.021. Epub 2014 Mar 20.
The knowledge of the association of polycyclic aromatic hydrocarbons (PAHs) with organic matter and carbonaceous materials is critical for a better understanding of their environmental transport, fate, and toxicological effects. Extensive studies have been done with regard to the relationship of PAHs with total organic carbon (TOC) and elemental carbon (EC) in different environmental matrices. The relationship between PAHs and the two subtypes of EC, char (combustion residues) and soot (produced via gas-to-particle conversion) also has been tested in field and laboratory experiments using reference materials. However, a direct comparison of associations of PAHs between with char and with soot in real environmental matrices has to our knowledge not yet been reported because of a lack of methodology to differentiate them. In this study, char and soot were measured using the IMPROVE method to test their associations with 12 EPA priority PAHs measured in topsoil samples (N=22, top 10 cm) collected from the Guanzhong Plain and in surface sediment samples (N=32, top 5 cm) from the Wei River (central China). In both soils and sediments, ∑12PAHs were more strongly associated with soot than with char, mainly due to the fact that soot and PAHs were produced in the same gas phase during combustion, had a strong affinity for each other, and were transported and deposited together, while char, the combustion residue, was transported differently to PAHs due to its large particle size. Stronger correlations between PAHs and the different carbon fractions (TOC, soot, and char) in sediments than in soils were observed, which is associated with the redistribution of PAHs among the organic matter pools in water because of the processes during soil erosion and sedimentation in the river.
了解多环芳烃（PAHs）与有机物和含碳物质之间的关联，对于更好地理解其环境迁移、归宿和毒理效应至关重要。针对不同环境基质中PAHs与总有机碳（TOC）和元素碳（EC）之间的关系，已经开展了广泛研究。PAHs与EC的两种亚型（焦炭（燃烧残留物）和烟灰（通过气-粒转化产生））之间的关系，也已在使用参考材料的野外和实验室实验中进行了测试。然而，据我们所知，由于缺乏区分它们的方法，尚未有关于真实环境基质中PAHs与焦炭和烟灰之间关联的直接比较报道。在本研究中，采用IMPROVE方法测量了焦炭和烟灰，以测试它们与在关中平原采集的表土样品（N = 22，表层10厘米）和渭河（中国中部）表层沉积物样品（N = 32，表层5厘米）中测得的12种美国环保署优先PAHs的关联。在土壤和沉积物中，∑12PAHs与烟灰的关联比与焦炭更强，主要是因为烟灰和PAHs在燃烧过程中在同一气相中产生，彼此具有很强的亲和力，并一起传输和沉积，而焦炭作为燃烧残留物，由于其粒径较大，与PAHs的传输方式不同。观察到沉积物中PAHs与不同碳组分（TOC、烟灰和焦炭）之间的相关性比土壤中更强，这与河流中土壤侵蚀和沉积过程导致PAHs在水体中有机质库之间的重新分配有关。
