中文摘要：

为研究沉积物中十溴联苯醚（BDE-209）的生物有效性，将淡水生态系统中常见的底栖动物中华圆田螺（Cipoangopaludinaca-hayensis）~k露于商品DE-83（主要包含92％的BDE-209、6％的BDE-206、1．5％的BDE-207和0．5％的BDE-208）染毒的沉积物，进行60d养殖实验。根据暴露期间中华圆田螺体内PBDEs含量与同系物组成的变化，探讨了田螺对DE．83的富集动力学、积累常数以及可能发生的生物转化。实验结果显示，DE-83主要同系物均能够被中华圆田螺积累，但是生物有效性非常低，BDE．209、BDE．207和BDE-206的吸收速率常数（ka）为0．029～0．042d^-1，BDE-207〉BDE-206〉BDE-209。依据动力学参数推算的生物-沉积物积累因子（BSAF）非常低，分别为0．05（BDE-209）和0．02（BDE-206和BDE-207）。暴露20d后，中华圆田螺体内有低溴代同系物检出，其含量随暴露时间延长而增加，说明BDE-209在中华圆田螺体内发生了生物转化。

英文摘要：

Cipangopaludina cahayensis was exposed to a commercial product of BDEs （DE-83） in sediments for 60 days to investigate the bioaccumulation and biotransformation ofnona- and deca-BDEs. The major con- geners in DE-83 were 92% of BDE-209, 6% of BDE-206, 1.5% of BDE-207 and 0.5% of BDE-208. The resultsshowed that all the major congeners were bioaccumulated in C. cahayensis. The uptake coefficients （ka） of nona- and deca-BDE congeners in C. cahayensis ranged from 0.029 to 0.042 d^-1, and the value of BDE-207 was slightly higher than those of BDE-206 and BDE-209. Nona- and deca-BDE congeners displayed low bioavail- ability with biota sediment accumulation factor （BSA F） of 0.02 for BDE-206 and BDE-207 and 0.05 for BDE-209, respectively. Lower brominated BDEs were detected in the tissue of C. cahayensis and their concentrations in- creased with the exposure duration, which could result from the biotransformation of high brominated BDEs.