河口滨岸悬浮颗粒物中多环芳烃分布与风险评价

DISTRIBUTION AND ECOLOGICAL RISK ASSESSMENT OF POLYCYCLIC AROMATIC HYDROCARBONS IN SUSPENDED PARTICULATE MATTER FROM THE YANGTZE ESTUARY AND COASTAL AREAS

通过收集长江口滨岸13个典型采样点上覆水中的悬浮颗粒物,分析了悬浮颗粒中多环芳烃(PAHs)的含量水平,探讨了PAHs的来源,并进行了生态风险评价。研究结果显示,EPA14种优控PAHs的总量在600～12 308 ng/g之间,平均值为5 373 ng/g,其组成主要以3环和4环PAH为主。受附近陆源输入的影响,顾路采样点的PAHs含量最高,此外,临近城市排污、滨岸工业开发区及河道排污口的采样点PAHs含量也较高,如石洞口、金山、白茆、浏河口等。结合PAHs不同环数的相对丰度与同分异构体荧蒽/芘、芘/苯并[a]蒽比值,初步推断出人类油污染及矿物燃料的不完全燃烧是悬浮颗粒物中PAHs的主要来源。此外,参照有关环境质量标准,发现悬浮颗粒物中萘、菲、芴、葸/苯并[b]荧蒽和苯并[k]荧蒽等化合物已经产生不同程度的生物影响效应。

The concentrations and spatial distribution of EPA 14 priority polycyclic aromatic hydrocarbons （PAHs） were studied in suspended particulate matter from the Yangtze Estuary and coastal areas. The results showed that the concentrations of total PAHs ranged from 600 ng/g to 12 303 ng/g with the average of 5 373 ng/g,and the components with 3～4 rings were dominant among PAH compounds. Sewage discharge from nearby city and highly industrial area in nearby coastal areas was the main factor affecting the spatial distribution of PAHs in suspended particulate matter. Based on the relative abundance of PAH rings,fuoranthene/prene ratio and prene/bnzo（a）pyrene ratio, the main possible sources of PAHs were identified as anthropogenic release of oil and oil products and uncompleted combustion of fossil fuels. Compared with the corresponding environmental guideline values,PAHs components, such as naphthalene, phenanthrene, fluorene, anthracene, Benzo （b） fluoranthene and benzo （k） fluoranthene, may have/had different level of biological effects.