三亚河表层沉积物中多环芳烃分布、来源解析及生态风险评价

Distribution, source and ecological risk assessment of polycyclic aromatic hydrocarbons (PAHs) in surface sediments from Sanya River

为了解三亚河表层沉积物中多环芳烃分布特征及生态风险,应用加压流体萃取、高效液相色谱检测表层沉积物中16种优先控制PAHs的含量和组成.结果表明,研究区域内表层沉积物中PAHs含量为3.23—493 ng·g^(-1)之间,平均浓度为211 ng·g^(-1),调查区域表层沉积物中PAHs含量与其它区域河流、湖库和海域沉积物中PAHs的含量比较,PAHs含量属于低值水平.调查区域表层沉积物中PAHs含量以3—5环为主,其对总浓度的贡献率为76.6%—100%,平均为84.4%,采用同分异构体比值分析结果显示PAHs主要来源于木柴、煤炭等燃烧源.质量基准法和质量标准法分析表明三亚河表层沉积物中的PAHs含量水平对该区域的生态环境影响较小,但对长期生活在该区域的底栖生物将构成轻微的潜在威胁,应采取相应管控措施,控制多环芳烃排入三亚河.

In order to understand pollution characteristics and ecological risk of polycyclic aromatic hydrocarbons(PAHs)in surface sediment from Sanya River,the concentration and composition of 16 priority PAHs were detected by accelerated solvent extraction(ASE)and high performance liquid chromatography(HPLC).The results showed that the total PAHs level(dry weight)reached 3.23—493 ng·g-1 and the average amount was 211 ng·g-1.Compared with other areas,the survey area was at low PAHs pollution level.The PAHs in the surface sediments of the survey area were primarily 3—5 rings.Source analysis showed that PAHs were mainly originated from combustion of firewood and coal.According to the assessment results of the Sediment Quality Guidelines(SQGs)and the Sediment Quality Standards(SQSs),the assessment results indicated that the PAHs in the surface sediments of the Sanya River are at a lower ecological risk level,but will pose a slight potential threat to the benthic organisms living in the region for a long time.Corresponding control measures should be taken to control the discharge of the PAHs into the Sanya River.