| Decabrominated Diphenyl Ether (BDE-209) is the brominated flame retandants which are synthesized organic compounds and used widely in the industry of furniture, automobile, electrical wire, cable and habiliment etc. In these products, BDE-209 is dissociated from other molecules and apt to enter the environment. Now, BDE-209 has been detected in atmosphere, water and soil. Some recently studies reported the volatilization and hydrolysis of BDE-209 were very difficult, it can easily accumulate in the sediments. BDE-209 could degradate to lower brominized diphenyl ethers, such as Octa-BDE and Nona-BDE under anaerobic conditions. These lower brominized diphenyl ethers are mutagens, hepatotoxic agents and carcinogens. In this article, the ultrasound-assisted extraction has been developmented to pretreat real samples. The adsorption of BDE-209 by activated sludge as well as anaerobic toxicity of BDE-209 and Di-BDE with glucose as co-substrate were studied, respectively. The results show that:1. The adsorption of BDE-209 on activated sludge reached a equilibration in initial 1h. The adsorption process could fit secend-order kinetic Lagergren model and adsorption isotherm followed the Freundlich equation . K is 457.09. The maximum adsorption is observed in neutral pH and 25℃.2. At the beginning of anaerobic reaction, the methanogens were greatly stimulated by BDE-209. From 15 h to 30 h, methanogens were gently inhibited by BDE-209. After 40 h, the production of methan stopped.3. Compared with the inhibition of methanogens, the relative activity and gas production, no obvious differences were found in BDE-209 and Di-BDE, but lower concentration of Di-BDE was more toxic than BDE-209.
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