环渤海近岸海域表层沉积物及底栖生物中PBDEs的赋存特征及富集行为

Occurrence and Bioaccumulation of Polybrominated Diphenyl Ethers( PBDEs) in Surficial Sediment and Benthic Organism in the Bohai Sea

多溴联苯醚（PBDEs）作为一种新型的持久性有机污染物,在海洋环境中广泛存在,研究PBDEs在不同介质中的赋存状态对于理解其环境行为及归趋具有重要的意义。通过采集不同区域沉积物及生物样品,考察了PBDEs在环渤海近岸海域表层沉积物及底栖生物中的含量及空间分布特征、污染模式及生物-沉积物富集因子。结果表明,环渤海沿岸表层沉积物中PBDEs总量（Σ10PBDEs）的浓度范围在0.446～26.8 ng·g-1（干重,dw）之间,中值为1.02 ng·g-1（dw）,底栖生物中PBDEs（Σ9PBDEs）的浓度范围为0.053～9.90 ng·g-1（dw）,中值为1.25 ng·g-1dw;沉积物中BDE-209为最主要的单体,平均丰度达到90.5%,生物体中主要以低溴代BDEs为主,其中单体BDE-47的含量最高,平均丰度范围为43.2%～49.7%;沉积物和生物中PBDEs的含量在空间上存在显著的差异,其中莱州湾和锦州附近区域的结果明显高于其他区域;5种不同的底栖生物对PBDEs均表现出一定的生物富集性,其中∑9PBDEs的BSAF值按从大到小的顺序为菲律宾蛤仔（0.43～4.06,mean=1.19）〉紫贻贝（0.34～2.86,1.03）〉四角蛤蜊（0.17～1.95,0.82）〉麻蛤（0.13～2.33,0.61）〉牡蛎（0.09～1.20,0.52）。辛醇水分配系数（log KOW）与不同物种BSAF值的相关性分析结果表明,除BDE-17单体外,其他单体的BSAF值表现出随log KOW的升高而下降的趋势。

As the new type of persistent organic pollutants, polybrominated diphenyl ethers（PBDEs） widely existed in the marine environment. Thereby it is meaningful to investigate the occurrence of PBDEs in different matrixes for understanding the environmental behavior and fate. In present study, the concentration, spatial distribution, congener pat-tern and bio-sediment accumulation factor were studied by collecting the surface sediments and benthic organisms around the Bohai sea. The results showed that the total concentration of PBDEs（Σ10PBDEs） in surficial sediments ranged from 0.446 to 26.8 ng·g-1（dry weight, dw） with the median value of 1.02 ng·g-1（dw）. The Σ9PBDEs in the benthic organisms ranged from 0.053 to 9.90 ng·g-1（dw） with the median of 1.25 ng·g-1（dw）. The congener BDE-209 predominated in the surficial sediments with the mean abundance of 90.5%. With a difference, the lowly brominated BDEs was dominated in the benthic organisms, and BDE-47 was the highest congener with the mean abundance of 43.2% ～ 49.7%. The spatial distribution of total PBDEs concentration in sediments and organisms showed a significant difference, which the results around the Laizhou bay and Jinzhou city were significantly higher than those from other areas. The five different species all showed the bioaccumulation and BSAF values of ∑9PBDEs with descending values followed the sequence of Ruditapes philippinarum（0.43 ～ 4.06, mean = 1.19） Mytilus edulis（0.34 ～ 2.86, 1.03） Mactra veneriformis（0. 17 ～ 1. 95, 0. 82） Anadara subcrenata（0. 13 ～ 2. 33, 0. 61） Ostrea gigas Thunberg（0.09 ～ 1.20, 0.52）. The correlation analysis between octanol-water partition coefficient（log KOW） and BSAFs in different species both showed a decrease trend with the increase of log KOWvalues except the congener BDE-17.