Abstract：
Contamination of polycyclic aromatic hydrocarbons (PAHs) in sediment has long been of great concern because of their toxic effects to benthic organisms. Sediment quality guidelines (SQGs) are the basis to evaluate the potential ecological risks of PAHs in sediments. Species sensitivity distribution (SSD) has been widely applied in deriving water quality criteria, but seldom employed in SQGs. In this study, SSD was used to derive the freshwater SQGs for four representative PAHs (naphthalene, phenanthrene, pyrene and benzo[a]pyrene) based on the sediment toxicity results. A linear relationship between the SQGs and octanol-water partition coefficient (log KOW) was developed, and applied to predict the SQGs of other twelve PAHs. The obtained SQGs were in the range of 0.46 - 1.79 mg/kg with a geometric mean of 0.97 mg/kg, which was proposed as the SQGs for total PAHs. Based on these SQGs, the risk quotients of PAHs in the sediments collected from Haihe River of China were calculated, and the toxic effects were also tested using three representative benthic organisms. As the risk quotients of the PAHs and heavy metals in the sediments were summed up, good correlations were found (p = 0.074 and 0.018) between them and the observed toxicities of the sediments. The SQGs developed for PAHs was promising in ecological risk assessment for contaminated freshwater sediments.
摘要：
沉积物中多环芳烃（PAHs）的污染一直备受关注，因为它们对底栖生物具有毒性作用。沉积物质量准则(SQGs)是评价沉积物中PAHs潜在生态风险的依据。物种敏感性分布(SSD)已广泛应用于得出水质标准，但很少在SQG工作。在这项研究中,SSD用于推导四种代表性PAHs的淡水SQG(萘，菲,芘和苯并[a]芘)基于沉积物毒性结果。建立了SQG与辛醇-水分配系数（logKOW）之间的线性关系，并应用于其他十二种多环芳烃的SQG预测。获得的SQG在0.46-1.79mg/kg范围内，几何平均值为0.97mg/kg，这被提议作为总PAHs的SQG。基于这些SQG，计算了中国海河沉积物中PAHs的风险商，还使用三种代表性底栖生物测试了毒性作用。总结了沉积物中PAHs和重金属的风险商，在它们与观察到的沉积物毒性之间发现了良好的相关性（p=0.074和0.018）。为PAHs开发的SQG在受污染的淡水沉积物的生态风险评估中很有希望。
