青岛近岸表层海水中PAHs的分布特征及物源初步解析

采用固相萃取-高效液相色谱-荧光检测法分析了青岛近岸海水中15种PAHs的质量浓度.结果表明,海水中PAHs的总量变化范围为8.23～272.02 ng.L-1,河口区质量浓度最高,远离城区的清洁区质量浓度最低.就组成特征而言,2～3环PAHs是其主要组分,占总量的质量分数为52.2%～93.8%,4～6环PAHs占总量的质量分数为6.2%～47.8%.表层海水中PAHs总浓度和DOC浓度之间有较好的相关性,相关系数为0.944 3.青岛湾表层海水中PAHs浓度组成相对稳定.利用Fl/(Fl+Py)和An/(An+Ph)分析表层海水中PAHs的来源,结果表明除清洁区表层海水中PAHs主要来源于煤和木材燃烧外,青岛近岸海水中的PAHs主要来源于石油制品和石油燃烧.

Distribution of PAHs in Surface Seawater of Qingdao Coast Area and Their Preliminary Apportionment

The 15 parent PAHs in surface seawater from Qingdao coastal areas have been quantified by solid phase extraction-high performance liquid chromatography with fluorescent detection. The results showed that the concentration of total PAHs ranged from 8.23 ng·L^-1 to 272.02 ng·L^-1, with highest concentration near estuary and lowest at rural location. As for PAHs composition, 2, 3 ring PAHs were dominant, with percentage ranged from 52.2% to 93.8%, while the remaining were 4 to 6 ring PAHs which were ranged from 6.2% to 47.8%. The concentration of total PAHs correlates strongly with dissolved organic carbon (R=0.9447) in surface seawater. There was no significant fluctuation in the concentration and composition of PAHs in surface seawater from Qingdao bay area in a one-month period. The two ratios of paired PAH isomeric compounds, fluoranthene to fluoranthene plus pyreneFl/(Fl+Py)] and anthracene to phenanthrene plus anthraceneAn/(An+Ph)], for source apportionment suggested that various petroleum related sources, such as oil spill and petroleum combustion, were the major origin at most sampling sites, except in clean areas where PAHs were predominantly derived from coal and wood combustion.