嘉陵江重庆段雨季悬浮颗粒相PAHs的污染分布及来源解析

Distribution and Sources of Polycyclic Aromatic Hydrocarbons in Suspended Particle Mater in Rainy Season from Jialing River in Chongqing

利用GC-MS研究了嘉陵江重庆段雨季13个悬浮颗粒相样品中的多环芳烃（PAHs）含量,同时应用比值法及主成因子分析/多元线性回归法（PCA-MLR）对PAHs进行来源解析。结果表明,16种PAHs总的浓度范围为447.47~1 344.92ng/g,平均浓度值为927.48ng/g,且在空间分布上呈现出＂升高-降低-升高-降低＂的趋势;PAHs的组成以4环PAHs为主,占PAHs总量的41.87%。汽油和柴油等化石燃料燃烧的交通源是嘉陵江重庆段雨季悬浮颗粒相PAHs的主要污染来源,其贡献率分别为37.97%和29.97%。通过效应区间中值（ERM）和效应区间低值（ERL）对悬浮颗粒相PAHs的生态风险进行了评价,结果表明,Acy、Ace、Fl和DahA具有一定的生态风险,其余12种PAHs都不超标,嘉陵江重庆段雨季悬浮颗粒相PAHs的生态风险比较小。

16 polycyclic aromatic hydrocarbons （PAHs） were measured by GC-MS for 13 suspended particle matter samples collected from Jialing River in Chongqing in rainy season. The results showed that the total concentrations of 16 PAHs ranged from 447.47 ng/g to I 344.92 ng/g, with a mean value of 927.48 ng/g. The concentration of total PAHs in suspended particle matter showed the trend of＂ up-down-up-down＂ in spatial distribution in the 13 sampling sites. The predominant PAHs in suspended particle matter were 4 ring PAHs, which accounting for 41. 87% of the tatal PAHs. The ratio analysis and principle factor analysis-multiple linear regression（PCA-MLR） indicated that the major source of PAHs was the engine combustion source, in which the proportion of gasoline combustion and diesel combustion were 37.79% and 29.97%, respectively. The ecological risk of PAHs was evaluated by the effects range median values （ERM） and the effects range low values （ERL）. The results illustrated that Acy, Ace, F1 and DahA had certain ecological risks, while the ERL values of other12 PAHs in all suspended particle matter samples were lower than the ERL guideline value, namely, PAHs in Jialing River in Chongqing could not cause obvious ecological risk.