典型电器工业区河涌沉积物中多环芳烃的分布、来源和潜在生态风险

Distribution and Potential Ecological Risk of Polycyclic Aromatic Hydrocarbons in the Sediments from Typical Electronics Industrial Zone

为综合评估电器加工制造业对纳污水体多环芳烃(PAHs)的污染影响,对广东典型电器工业区佛山市顺德区容桂街道河涌沉积物的PAHs含量进行了空间和垂直分布、来源以及生态风险评估研究.结果表明,16种优先控制PAHs中有12种检出率达100%,其余4种具有不同的检出率.ΣPAHs含量范围为343.5～2 099μg.kg-1,均值为1 215.9μg.kg-1.PAHs组成特点为2～3环>4环>5～6环.在0～40 cm垂直尺度内,4个分层层面的ΣPAHs含量和种类均无显著变化.同分异构体比率分析显示,空间尺度上PAHs主要污染源来自石油、生物质以及木柴燃烧等活动.垂直尺度上燃烧类型反映了从生物质向石油燃烧为主的转变.河涌沉积物总量污染指标和污染因子指标显示了相同的重度污染特征,各监测断面污染程度由高到低为:S7>S2>S4>S3>S6>S1>S5.沉积物质量基准法(SQGs)评价显示S7、S2、S3等位点具有潜在的生态风险.包含居民区和制造业集中区的各监测点ΣPAHs含量分布显示,该地区PAHs污染和电器制造业存在没有直接相关性.

In order to investigate the polycyclic aromatic hydrocarbons(PAHs) contamination status in a river of a typical electrical equipment industrial area,Ronggui,Foshan,8 sediments simples were collected.The results showed that 12 components of PAHs were detected in all sediment samples,and the other 4 components were also detected in different degree.The total 16 EPA priority PAHs contents in surface sediments varied from 343.5 μg·kg-1 to 2 099 μg·kg-1(dry wt),with an average of 1 215.9 μg·kg-1,and no significant variation was found in vertical distribution.The 2 to 3 aromatic rings were the dominant PAHs,and they accounted for 50.6% to 82.5% of the total PAHs.Diagnostic ratios were used to identify the possible sources of PAHs,and the results indicated that PAHs were mainly pyrogenic origin.Sediments were polluted by PAHs heavily according to Maliszewska-Kordybach's standard,the very high risk level was also confirmed by the contamination factors assessment which was investigated by comparison with the background area(S0).The assessment by the method of sediment quality guidelines(SQGs) and relative contamination factor(RCF) demonstrated that adverse biological toxicity effect might occasionally happen in a few sampling sites,and the ecological risk components included acenaphthene(Ace),fluorine(Flu),and phenanthrene(Phe).