长江中游沉积物中多溴联苯醚的污染特征及风险评价

多溴联苯醚(PBDEs)具有高毒性和生物累积性,进入水体后易与有机质相结合,成为PBDEs污染物的重要归宿,对人类健康和水生生态系统造成潜在的危险.为揭示多溴联苯醚(PBDEs)在长江中游流域的污染现状,通过采集该地区流域内13个表层沉积物样品,采用高分辨气相色谱/高分辨质谱法(HRGC/HRMS)对沉积物中9种PBDEs同类物进行分析.结果表明该地区沉积物中9种PBDEs的含量范围(干重)约为46.1~326 pg·g~(-1),而BDE-99是其中最主要的贡献单体,平均贡献率约为51.6%;其次是BDE-47,约为19.6%.与国内外其他海域的研究相比,长江中游沉积物中PBDEs残留量处于较低水平.通过测定沉积物中总有机碳(TOC),研究结果发现PBDEs含量与TOC无明显的正相关关系.结合商值法对PBDEs的健康风险进行初步评估,结果表明,本研究中PBDEs对人体产生的健康风险较小.

Pollution Characteristics and Risk Assessment of Polybrominated Diphenyl Ethers in the Surface Sediments from Middle Reaches of the Yangtze River

Polybrominated diphenyl ethers (PBDEs) are highly lipophilic compounds with high toxicity and long-term bioaccumulation, which have strong affinities to suspended particulates in water. So PBDEs are easily adsorbed to sediments, and cause potential risks to human beings and aquatic ecosystem. In order to investigate the levels and patterns of PBDEs in the Yangtze River, 13 surface sediment samples were collected from the middle reaches of the regions and the concentrations of 9 PBDE congeners in the sediments were determined using High Resolution Gas Chromatography/High Resolution Mass Spectrometry (HRGC/HRMS). The total concentrations of PBDEs ranged from 46.1 to 326 pg ·g^-1 dry weight. BDE-99 and BDE-47 were the dominant PBDE congeners, which averagely contributed 51.6% and 19.6%, respectively. The concentrations of PBDEs were relatively low compared to those in other studies. The total organic carbon (TOC) was also analyzed in this study, and the results indicated that there was no obvious positive correlation between the levels of PBDEs and TOC. In addition, based on the PBDEs concentration levels, the ecotoxicological risks of PBDEs contamination in surface sediments of the Yangtze River were evaluated by the quotient method. The results showed that the levels of PBDEs were considerably low and these compounds should have no risk to human health.