State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai 200237, PR China.
J Hazard Mater. 2013 Feb 15;246-247:96-102. doi: 10.1016/j.jhazmat.2012.11.065. Epub 2012 Dec 17.
Leaching assessment on five heavy metals (copper, zinc, lead, nickel and cadmium) and two brominated flame retardants (BFRs), polybrominated diphenyl ethers (PBDEs) and tetrabromobisphenol A (TBBPA), from waste printed circuit boards (WPCBs) were conducted using various leaching methods. The mean leaching concentrations of copper were the highest in both toxicity characteristic leaching procedures (TCLP) and synthetic precipitation leaching procedures (SPLP) tests at 8.6 mg/L and 1.1mg/L, while only lead (6.2mg/L) exceeded the TCLP criteria and Chinese EPA regulatory limit (both 5.0mg/L). However, PBDEs and TBBPA were not detected in TCLP and SPLP tests. Then the BFRs leaching trends and potential leachabilities were further investigated in actual landfill leachates using a modified method. Leaching characteristics that fast-leaching initially followed by slow-desorption over time were generally observed. In landfill leachate tests, the highest leaching concentrations of PBDEs and TBBPA were determined at 30.39 and 12.27 μg/L. Meanwhile, the highest leaching rates were estimated to reach 0.08% and 1.00%, respectively, which were significantly influenced by the dissolved organic carbon contents of extracts, the hydrophobicities of target BFRs and the specific surface areas of WPCBs materials. These results proved that leaching from WPCBs was a significant emission source of BFRs in landfill and electronic waste recycling dumpsite.
采用多种浸出方法对来自废印刷电路板（WPCB）的五种重金属（铜、锌、铅、镍和镉）和两种溴化阻燃剂（BFRs），即多溴二苯醚（PBDEs）和四溴双酚 A（TBBPA）进行了浸出评估。在毒性特征浸出程序（TCLP）和合成沉淀浸出程序（SPLP）测试中，铜的平均浸出浓度最高，分别为 8.6mg/L 和 1.1mg/L，而只有铅（6.2mg/L）超过了 TCLP 标准和中国 EPA 监管限值（均为 5.0mg/L）。然而，在 TCLP 和 SPLP 测试中未检测到 PBDEs 和 TBBPA。然后，使用改良方法进一步研究了实际垃圾填埋场浸出液中 BFRs 的浸出趋势和潜在浸出率。通常观察到最初快速浸出，随后随时间缓慢解吸的浸出特征。在垃圾填埋场浸出测试中，PBDEs 和 TBBPA 的最高浸出浓度分别为 30.39μg/L 和 12.27μg/L。同时，估计最高浸出率分别达到 0.08%和 1.00%，这受到提取物中溶解有机碳含量、目标 BFRs 的疏水性以及 WPCB 材料的比表面积的显著影响。这些结果证明，WPCB 的浸出是填埋场和电子废物回收场中 BFRs 的重要排放源。
