School of Applied Sciences, RMIT University, Melbourne, Australia.
Sci Total Environ. 2010 Mar 1;408(7):1604-11. doi: 10.1016/j.scitotenv.2009.11.059. Epub 2010 Jan 29.
The aim of this study was to quantify the amount of polybrominated diphenyl ethers (PBDEs) released into the environment (biosolids, effluent) from a conventional Australian activated sludge treatment wastewater treatment plant (WWTP). The concentration of PBDE congeners was measured at various treatment stages and included four aqueous samples (raw, primary, secondary and tertiary effluents) and three sludges (primary, secondary and lime stabilized biosolids), collected at three sampling events over the course of the experiment (29 days). Semi-permeable membrane devices (SPMDs) were also installed for the duration of the experiment, the first time that SPMDs have been used to measure PBDEs in a WWTP. Over 99% of the PBDEs entering the WWTP were removed through the treatment processes, principally by sedimentation. The main congeners detected were BDE 47, 99 and 209, which are characteristic of the two major commercial formulations viz penta-BDE and deca-BDE. All the PBDE congeners measured were highly correlated with each other, suggesting a similar origin. In this case, the PBDEs are thought to be from domestic sources since domestic wastewater is the main contribution to the in-flow (approximately 95%). The mean concentration of SigmaPBDEs in chemically stabilized sewage sludge (biosolids) was 300microg kg(-1) dry weight. It is calculated that 2.3+/-0.3kg of PBDEs are disposed of each year with biosolids generated from the WWTP. If all Australian sewage sludge is contaminated to at least this concentration then at least 110kg of PBDEs are associated with Australian sewage sludge annually. Less than 10g are released annually into the environment via ocean outfall and field irrigation; this level of contamination is unlikely to pose risk to humans or the environment. The environmental release of treated effluent and biosolids is not considered a large source of PBDE environmental emissions compared to the quantities used annually in Australia.
本研究旨在量化常规澳大利亚活性污泥处理废水处理厂（WWTP）向环境（生物固体、废水）中释放的多溴二苯醚（PBDEs）量。在各个处理阶段测量了 PBDE 同系物的浓度，包括四个水样（原水、一级、二级和三级出水）和三个污泥（一级、二级和石灰稳定生物固体），在实验过程中三个采样事件采集（29 天）。还安装了半渗透膜装置（SPMDs）进行实验，这是 SPMD 首次用于测量 WWTP 中的 PBDEs。超过 99%的 PBDEs 在处理过程中被去除，主要是通过沉淀。检测到的主要同系物是 BDE 47、99 和 209，这是两种主要商业配方 penta-BDE 和 deca-BDE 的特征。测量的所有 PBDE 同系物彼此高度相关，表明它们具有相似的来源。在这种情况下，PBDEs 被认为来自家庭来源，因为家庭废水是流入物的主要贡献者（约 95%）。化学稳定污水污泥（生物固体）中 SigmaPBDEs 的平均浓度为 300μgkg(-1)干重。据计算，每年从 WWTP 产生的生物固体中有 2.3+/-0.3kg 的 PBDEs被处理掉。如果澳大利亚所有的污水污泥都受到至少这种浓度的污染，那么每年与澳大利亚污水污泥相关的 PBDEs 至少有 110kg。每年通过海洋排放口和田间灌溉向环境中释放的不到 10g；这种污染水平不太可能对人类或环境构成风险。与澳大利亚每年使用的数量相比，处理后的废水和生物固体的环境释放被认为不是 PBDE 环境排放的主要来源。
