渤海西北部海域表层水体中PAHs的分布、来源及风险评价

摘要

利用气相色谱质谱仪(GC/MS)测定曹妃甸、山海关及沧州渤海新区表层海水样品中16种优先控制PAHs.结果表明,三个地区近岸海域表层海水中∑PAHs含量分别为14.1-226ng/L、29.9-229ng/L和97.4-254ng/L;平均含量分别为108ng/L、102ng/L和204ng/L.沧州渤海新区近岸∑PAHs含量高于曹妃甸和山海关近岸的含量,且检出的PAHs种类多.与其它国家和地区表层水体样品中PAHs含量相比较,本研究区域表层海水中PAHs含量处于中等水平.高低分子量比值和异构体比值分析表明,渤海西北部海域表层海水中PAHs主要来源于石油污染,此外,生物质及煤的燃烧也有一定贡献.应用商值法对研究区域表层海水中PAHs的生态风险进行评价,结果发现生态风险非常小.%Surface water samples were collected from the northwest Bohai Sea, including Caofeidian, Shanhaiguan and Cangzhou areas, to determine the 16 priority polycyclic aromatic hydrocarbons (PAHs) by GC/MS in September, 2010. Total PAHs concentrations in the surface water of Caofeidian, Shanhaiguan and Cangzhou area varied in the range of 14.1-226ng/L, 29.9-229ng/L and 97.4-254ng/L, with mean values of 108ng/L, 102ng/L and 204ng/L, respectively. The level of PAHs in Cangzhou area was higher than those in Caofeidian and Shanhaiguan areas, with more PAHs congeners detected. Compared with the reports about PAHs in water samples from different area, the concentrations of PAHs in the surface water from the northwest Bohai Sea were at the median level. The main sources of PAHs came from oil pollution by assessing the profile of different molecular weight and the ratios of isomer. Ecological risk was very low by the quotient assessment method.