废旧电器拆解区河流沉积物中多溴联苯醚(PBDEs)的污染特征与生态风险

在流经某废旧电器拆解区域的河段中采集沉积物样品,研究了该区域河流中多溴联苯醚(PBDEs)的污染特征和生态风险.结果表明,在所有沉积物样品中PBDEs含量在101~20400 ng·g-1之间,平均浓度为3700 ng·g-1,其中主要单体为BDE209,在23个样品中的平均比例达到94%以上;在河流中分布呈现出上游和下游低,中游高,而下游平均浓度比上游高的趋势,在拆解园区附近浓度达到最高;与其它地区相比,该地区PBDEs污染相对较为严重;废旧电器的拆解是该区域沉积物中PBDEs污染主要来源.经测算,当地近40年的拆解活动中共向该河流中排放了多溴联苯醚0.39 t,其中BDE209为0.36 t;采用危害商数法对沉积物中PBDEs进行了初步的生态风险评估,结果表明,该河流沉积物中OctaBDEs和DecaBDEs生态风险较低,而PentaBDEs则风险较高,可能对环境造成危害.

Pollution Characteristics and Ecological Risk of Polybrominated Diphenyl Ethers (PBDEs) in River Sediments from an Electrical Equipment Dismantling Area

Polybrominated diphenyl ethers (PBDEs) were determined in sediments collected from a river which through an electrical equipment dismantling area. The results showed that concentrations of PBDEs ranged from 101 to 20400 ng ·g^-1 with an average of 3700 ng ·g^-1, and BDE209 was the most dominant homologue accounted for more than 94% of all detected homologues. The concentration of PBDEs was higher in the middle of river than that in upstream and downstream and the average concentration in downstream was higher than the upstream, with a peak of concentration in the area near by dismantling industrial park. PBDEs pollution in this region is relatively serious compared with other regions. It was estimated that 0.39 t PBDEs (including 0.36 t BDE209)was discharged into the river as a result of dismantling industrial activities in last 40 years. A preliminary ecological risk assessment for PBDEs in sediments was conducted by hazard quotient method, the results showed that the OctaBDEs and DecaBDEs were in a low ecological risk, while the PentaBDEs was in a particularly high risk and could cause great harm to the environment.