环渤海渔港沉积物多环芳烃的污染特征和生态风险评价

Pollution characteristics and ecological risk assessment of polycyclic aromatic hydrocarbons in sediments from fishing ports along the coast of Bohai Sea

2019年5—6月采集了环渤海20个渔港的沉积物样品,采用高效液相色谱紫外/荧光检测器串联方法对16种多环芳烃(PAHs)进行检测,分析了其分布和组成特征,采用比值法和正定矩阵因子模型法(PMF)对PAHs进行定量源解析,采用效应区间中低值法和中值商法评估其生态风险.10种PAHs的检出率达到100%,表明PAHs在沉积物中广泛存在.16种PAHs总含量为1092.87—4196.88μg·kg^(-1),平均值为2642.05μg·kg^(-1).相比国内外其它海域,环渤海渔港PAHs含量处于中高水平,含量由高到低依次为辽东半岛>京津冀地区>山东半岛.在组成上,低环PAHs(2—3环)占比大于高环(4—6环)PAHs.渔港PAHs主要来自石油污染,贡献率为51.6%;石油燃烧和生物质燃烧的贡献率分别为22.1%和17.4%,煤炭燃烧的贡献率为8.9%.环渤海渔港PAHs总体呈现中低生态风险,主要来源于低环PAHs.研究环渤海渔港表层沉积物中PAHs污染情况,对环渤海生态环境保护和治理具有重要意义.

Surface sediment samples were collected from 20 fishing ports along the Bohai Sea in May to June 2019,and 16 US EPA priority polycyclic aromatic hydrocarbons(PAHs)were measured using high performance liquid chromatography with UV and fluorescence detector.The distribution and composition characteristics of PAHs were analyzed and the sources of PAHs were determined with methods of ratio between PAHs and positive matrix factorization(PMF).The ecological risk assessment of PAHs was carried out using effects range low(ERL),effects range median(ERM)and mean effects range median(M-ERM-Q).The percentage of positive results of PAHs was high and10 PAHs reached up to 100%,indicating that PAHs are widespread pollutants in fishing ports.The total concentrations of 16 PAHs(∑;PAHs)ranged from 1092.87μg·kg^(-1) to 4196.88μg·kg^(-1),with the mean of 2642.05μg·kg;.Compared with surface sediments in other coastal areas around the world,the concentrations of PAHs in this study were at a middle-high level.In contrast,the Liaodong Peninsula presented the highest PAHs concentration,followed by the Beijing-Tianjin-Hebei region and the Shandong Peninsula.PAHs with low ring numbers(two and three rings)had a higher contribution than those with high ring numbers(four,five,and six rings).The potential sources of PAHs in surface sediment from fishing ports included the oil emission pollution,oil combustion,oil combustion,biomass combustion and coal combustion,with a contribution rate of 51.6%,22.1%,17.4%,and 8.9%,respectively.PAHs in surface sediments presented a medium-low ecological risk which mainly were attributed to PAHs with low ring numbers.It is great significance to study the pollution of PAHs in the surface sediments from fishing ports in the Bohai Sea.