福州内河沉积物中多环芳烃的分布、来源及其风险评价

对福州市11个内河表层沉积物样品中15种多环芳烃(PAHs)含量进行了分析,结果表明,沉积物中 15种PAHs的总量在84.3~2248.1 μg/kg之间,均值为899.6μg/kg,处于中等污染水平,且呈现中部和南部高,东部、西部和北部低的地理分布特征.沉积物中15种PAHs的总量与有机碳总量(TOC)呈显著性正相关(r=0.7829, P1,具有一定的生态风险.

Distribution,sources and ecological risks of PAHs in inland river sediments of Fuzhou City

The concentrations of 15 PAHs in eleven surface sediment samples collected from inland rivers in Fuzhou City were analyzed. The results showed that the total concentrations of 15 PAHs ranged from 84.3 to 2248.1 μg/kg and the average was 899.6 μg/kg, which was at the intermediate pollution level. The geographical distribution of the total PAHs can be characterized by higher concentration in the southern and central region and lower concentration in the northern, eastern and western region of Fuzhou city. The total concentration of 15 PAHs had a significantly positive correlation with the total organic carbon concentration in sediments (r=0.7829, P<0.05). Among the 15 PAHs, the concentration of 11 PAH isomers had significant positive correlations with the concentration of the total organic carbon (r=0.6557~0.9256, P<0.05),and the concentration of 12 PAH isomers had highly significant correlations between each other (r=0.6706~0.9908, P<0.01). The diagnostic ratios indicated that the sources of PAHs in sediments were mixed and mainly derived from local traffic pollution. The ecological risks of PAHs in sediments were evaluated according to the sediment quality guideline ERL (Effects Range Low). The concentrations of Ace, Flu and Phe in two sediment samples and those of Ace and Flu in one sediment sample exceeded ERL value. In the case of average ERL quotient of the PAH species, only one sediment sample had the average ERL quotient value greater than 1, and had certain ecological risks.