Wang Ji-Zhong, Zhang Kai, Liang Bo, Zeng Eddy Y
School of Earth and Space Sciences, University of Science and Technology of China, Hefei, 230026, China.
J Environ Monit. 2011 Dec;13(12):3336-42. doi: 10.1039/c1em10599j. Epub 2011 Oct 28.
In order to evaluate the effect of local anthropogenic activities on Chaohu Lake, one of the most eutrophicated lakes in China, surface sediments have been collected from the whole lake with 0.05 × 0.05 degree latitude/longitude resolution and in the estuaries of three main inflowing rivers. The concentrations of the 28 polycyclic aromatic hydrocarbons (PAHs) determined were in a range 82.4-13,000 ng g(-1) with an average value of 1670 ng g(-1) dry weight for total 28 PAHs (referred to as Σ(28)PAH). Amongst the 28 PAHs, 16 are listed as high priority PAHs by the USEPA and they were in the range of 60.8-10,200 ng g(-1) with an average value of 1230 ng g(-1) for the total of them (referred to as Σ(16)PAH); 7 are known as carcinogenic PAHs and their levels ranged from 34.2 to 6400 ng g(-1) with an average of 815 ng g(-1) in total (referred to as Σ(7)PAH). Chaohu Lake was considered significantly polluted by PAHs through the comparison with the PAH burdens in fresh-water lakes both in China and worldwide. Toxic units (TUs) evaluation showed some sampling locations possibly were over the median lethal level for benthic invertebrate. The highest PAH concentrations were found in sediments from the Nanfei River estuary, suggesting the major contributor of PAHs contamination to the lake. The PAHs with four and five rings were found to be dominant among the PAHs detected in all of the sediment samples, and perylene was the most abundant. Σ(16)PAH had a good correlation with those PAHs from pyrogenic sources, such as anthracene and phenanthrene, but a poor correlation with perylene. The results demonstrated that the environmental behavior of PAHs from pyrogenic sources is significantly different to that of perylene from diagenetic sources. The PAHs in sediments were mainly from traffic-related emission by qualitatively assessing with the diagnostic ratios of PAH isomers, and the ratios for low molecular weight PAHs were strongly altered during their transport.
为了评估当地人为活动对中国富营养化最严重的湖泊之一巢湖的影响，已在整个巢湖以0.05×0.05度的经纬度分辨率以及三条主要流入河流的河口采集了表层沉积物。所测定的28种多环芳烃（PAHs）的浓度范围为82.4 - 13000 ng g⁻¹，28种PAHs的总含量（称为Σ(28)PAH）干重平均值为1670 ng g⁻¹。在这28种PAHs中，有16种被美国环境保护局列为高优先级PAHs，它们的含量范围为60.8 - 10200 ng g⁻¹，其总量（称为Σ(16)PAH）平均值为1230 ng g⁻¹；7种是已知的致癌PAHs，其含量范围为34.2至6400 ng g⁻¹，总量平均为815 ng g⁻¹（称为Σ(7)PAH）。通过与中国和世界范围内淡水湖泊中的PAH含量进行比较，巢湖被认为受到PAHs的严重污染。毒性单位（TUs）评估表明，一些采样地点可能超过了底栖无脊椎动物的半数致死水平。在南淝河河口的沉积物中发现了最高的PAH浓度，这表明PAHs污染湖泊的主要来源。在所有沉积物样品中检测到的PAHs中，四环和五环PAHs占主导地位，苝的含量最高。Σ(16)PAH与来自热解源的PAHs（如蒽和菲）具有良好的相关性，但与苝的相关性较差。结果表明，热解源PAHs的环境行为与成岩源苝的环境行为有显著差异。通过PAH异构体的诊断比值进行定性评估，沉积物中的PAHs主要来自与交通相关的排放，并且低分子量PAHs在其迁移过程中比值发生了强烈变化。
