Zhao Junying, Guo Huaming, Ma Jie, Shen Zhaoli
a School of Environmental Science and Safety Engineering , Tianjin University of Technology , Tianjin , China.
Int J Phytoremediation. 2015;17(1-6):355-62. doi: 10.1080/15226514.2013.837028.
High-arsenic groundwater in inland basins usually contains high concentrations of fluoride. In the present study, the effects of fluoride on arsenic uptake by Pteris vittata and on arsenic transformation in growth media were investigated under greenhouse conditions. After P. vittata was hydroponically exposed to 66.8 μM As (V) in the presence of 1.05 mM F- in the form of NaF, KF, or NaF+KF for 10 d, no visible toxicity symptoms were observed, and there were not significant differences in the dry biomass among the four treatments. The results showed that P. vittata tolerated F- concentrations as high as 1.05 mM but did not accumulate fluoride in their own tissues. Arsenic uptake was inhibited in the presence of 1.05 mM F-. However, in hydroponic batches with 60 μM As (III) or 65 μM As (V), it was found that 210.6 and 316.0 μM F(-) promoted arsenic uptake. As(III) was oxidized to As(V) in the growth media in the presence and absence of plants, and F- had no effect on the rate of As(III) transformation. These experiments demonstrated that P. vittata was a good candidate to remediate arsenic-contaminated groundwater in the presence of fluoride. Our results can be used to develop strategies to remediate As-F-contaminated water using P. vittata.
内陆盆地的高砷地下水通常含有高浓度的氟化物。在本研究中，在温室条件下研究了氟化物对蜈蚣草吸收砷以及对生长介质中砷转化的影响。将蜈蚣草在含有1.05 mM以NaF、KF或NaF + KF形式存在的F-的情况下，水培暴露于66.8 μM As(V)中10天，未观察到明显的毒性症状，并且四种处理之间的干生物量没有显著差异。结果表明，蜈蚣草能够耐受高达1.05 mM的F-浓度，但不会在其自身组织中积累氟化物。在存在1.05 mM F-的情况下，砷的吸收受到抑制。然而，在含有60 μM As(III)或65 μM As(V)的水培批次中，发现210.6和316.0 μM F(-)促进了砷的吸收。在有植物和无植物的情况下，As(III)在生长介质中均被氧化为As(V)，并且F-对As(III)的转化速率没有影响。这些实验表明，在存在氟化物的情况下，蜈蚣草是修复受砷污染地下水的良好候选植物。我们的结果可用于制定利用蜈蚣草修复As-F污染水的策略。
