条子河表层沉积物中多环芳烃的分布、来源及生态风险评价

为了解辽河典型支流四平市条子河表层沉积物中多环芳烃(PAHs)的污染状况,选取10个采样点采集表层沉积物样品,测定了其中的PAHs质量浓度、分析了其空间分布特征、应用多种方法解析了PAHs的来源并对其生态风险进行了评价。结果表明,条子河表层沉积物中PAHs质量浓度范围为601.3~2 906.2 ng/g,算数平均值为1 527.3 ng/g,所检出的PAHs的环数均为2-4环化合物,且以4环为主,占PAHs的63.6%~71.5%。来源解析表明条子河表层沉积物中的PAHs主要来源于煤和生物质的燃烧。生态风险评价结果显示,3环的苊和芴在各个采样点可能产生一定的负面毒性效应;位于条子河干流、临近四平市城区采样点的沉积物中PAHs对生物可能产生中低毒性;而其他采样点存在综合生态风险的可能性很小。

Distribution, sources, and risk assessment of polycyclic aromatic hydrocarbons in surface sediments from Tiaozi River

In order to investigate the pollution of polycyclic aromatic hydrocarbons (PAHs) in surface sediments of Tiaozi River in Siping city, a typical tributary of Liaohe River, concentrations of PAHs in sediments from ten representative sampling sites was determined. The spatial distribution, possible sources and ecological risk of PAHs were also evaluated. Results indicated that total PAHs concentrations in the sediments varied from 601.3 to 2906.2 ng/g, with an average of 1527.3 ng/g. All the PAHs detected out in the sediments were composed of 2-4 ring PAHs and 4 ring PAHs accounted for 63.6%-71.5% of the total PAHs concentrations. Source appointment showed that the combustion of biomass and coal was the major source of PAHs in the sediments of Tiaozi River.Ecological risk assessment showed that acenaphthene and fluorence in the sediments of all the sampling sites could cause a negative effect on organisms. Sediment PAHs in the mainstream nearby Siping city could have low-medium toxicity, but others have little toxicity.