Liang Shuang, Guan Dong-Xing, Li Jie, Zhou Chun-Yang, Luo Jun, Ma Lena Q
State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Jiangsu 210023, China; Central and Southern China Municipal Engineering Design & Research Institute, Wuhan, Hubei 430010, China.
State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Jiangsu 210023, China.
Chemosphere. 2016 May;151:94-100. doi: 10.1016/j.chemosphere.2016.02.070. Epub 2016 Mar 15.
The effect of aging on the bioaccessibility of As and Pb in three soils spiked with As (40 or 400 mg kg(-1)), Pb (150 or 1500 mg kg(-1)) or As + Pb (40 mg kg(-1) As and 150 mg kg(-1) Pb) were investigated using the physiologically based extraction test (PBET). Prolonged aging in soils resulted in a decrease in As/Pb bioaccessibility, especially within the first month. After 76 weeks, As/Pb bioaccessibility in soils decreased to a stable level, with 48-84% and 8-34% for bioaccessible As and Pb respectively in the intestinal phase, illustrating that As in spiked soils was much more bioaccessible than Pb. Correlation analysis between sequential extraction data and PBET results showed that the non-specifically sorbed As contributed the most to bioaccessible As, while Pb bound with carbonates and exchangeable fractions were the source for bioaccessible Pb. For future work, minerals containing As and/or Pb instead of their soluble salts can be added to uncontaminated soils to better simulate the natural aging processes.
采用基于生理学的提取试验（PBET）研究了老化对三种添加了砷（40或400毫克/千克(-1)）、铅（150或1500毫克/千克(-1)）或砷+铅（40毫克/千克(-1)砷和150毫克/千克(-1)铅）的土壤中砷和铅生物可及性的影响。土壤中的长期老化导致砷/铅生物可及性降低，尤其是在第一个月内。76周后，土壤中砷/铅生物可及性降至稳定水平，在肠道阶段，生物可及性砷和铅分别为48-84%和8-34%，这表明添加砷的土壤中砷的生物可及性远高于铅。连续提取数据与PBET结果之间的相关性分析表明，非特异性吸附的砷对生物可及性砷的贡献最大，而与碳酸盐和可交换部分结合的铅是生物可及性铅的来源。对于未来的工作，可以将含砷和/或铅的矿物而非其可溶性盐添加到未受污染的土壤中，以更好地模拟自然老化过程。
