从天津滨海地区不同地表水表层沉积物取样,测定4类持久性有机污染物即多环芳烃(PAHs)、有机氯农药(OCPs)、多氯联苯(PCBs)和多溴联苯醚(PBDEs)的含量,目的是了解该区4类持久性有机污染物的含量特征并对其生态风险进行评估.结果表明,天津滨海地区10个沉积物采样点中16种优先控制的PAHs均有检出,PAHs总含量范围为274.06~2 656.65μg.kg-1、平均为1 198.51μg.kg-1.化石燃料(例如煤和汽油)的燃烧是该区表层沉积物中PAHs的主要来源,个别地方混有石油类产品的输入.在大沽排污河采样点,22种OCPs总含量为3 103.36μg.kg-1,35种PCBs和14种PBDEs的总含量分别为87.31μg.kg-1和13.88μg.kg-1.其它采样点OCPs、PCBs和PBDEs的含量均较低.该区表层沉积物中总有机碳含量与PAHs的相关性很好,但与OCPs、PCBs和PBDEs的相关性较差,这可能与PAHs主要来自面源污染而其它污染物主要来自点源污染有关.沉积物中PAHs(尤其是低分子量PAHs)的风险较大,在多个采样点中,萘和/或苊的含量超过可能效应浓度,极有可能对底栖生物产生不良影响.在大沽排污河,七氯环氧化物和林丹(gamma-BHC)超过可能效应浓度,极有可能对底栖生物产生不良影响;其它采样点OCPs的生态风险较小.整体上,PCBs和PBDEs的生态风险较小.
Surface sediments were sampled from various surface water bodies in Tianjin coastal area,and four types of persistent organic pollutants including polycyclic aromatic hydrocarbons(PAHs),organic pesticides(OCPs),polychlorinated biphenyl(PCBs) and polybrominated diphenyl ethers(PBDEs) were measured.The purposes were to investigate the concentration characteristics of the four types of pollutants and to assess their ecological risks.The results showed that all the 16 priority PAHs were detected from the 10 sediments sampled from the Tianjin coastal area.The total concentrations of the 16 PAHs ranged from 274.06 μg·kg-1 to 2 656.65 μg·kg-1,with the average being 1 198.51μg·kg-1.Combustion of fossil fuel such as coal and gasoline was the major source of PAHs in the surface sediments,while input of petroleum products might occur in some locations.In the Dagu discharging river,the total concentration of 22 OCPs was 3 103.36 μg·kg-1,the total concentration of 35 PCBs and the total concentration of 14 PBDEs were 87.31 μg·kg-1 and 13.88 μg·kg-1,respectively.The concentrations of OCPs,PCBs and PBDEs in other sampling locations were low.The total organic carbon in the surface sediments had good correlation with PAHs but not with OCPs,PCBs and PBDEs,and this might be due to the fact that PAHs mainly came from area pollution while the other compounds mainly came from point pollution.In the sediments,PAHs(particularly low molecular weight PAHs) had high ecological risk;in multiple locations,the concentrations of naphthalene and/or acenaphthene exceeded their probable effect concentrations,indicating that they were most likely causing adverse effects to benthonic organisms.In the Dagu discharging river,the concentrations of heptachlor epoxide and lindane(gamma-BHC) exceeded their probable effect concentrations and were most likely causing adverse effects to benthonic organisms.The OCPs in other sampling locations had low ecological risk.Overall,PCBs and PBDEs had low ecological risk.