es4055077_si_001.pdf (695.34 kB)
Role of Nanoparticles in Controlling Arsenic Mobilization from Sediments near a Realgar Tailing
journal contribution
posted on 2014-07-01, 00:00 authored by Guowen Dong, Yaohua Huang, Qiangqiang Yu, Yuanpeng Wang, Haitao Wang, Ning He, Qingbiao LiMicrocosm experiments
were conducted to investigate the mechanism
of microbial-mediated As mobilization from high arsenic tailing sediments
amended with nanoparticles (NPs). The addition of SiO2 NPs
could substantially stimulate arsenic mobilization in the sodium acetate
amendment sediments. However, the addition of Fe2O3 and Fe3O4 NPs restrained arsenic release
because these NPs resulted in Fe–As coprecipiate. Moreover,
NP additions in sediments amended with sodium acetate as the electron
donor clearly promoted microbial dissimilatory iron reduction. Nearly
4 times the Fe(II) (11.67–12.87 mg·L–1) from sediments amended with NPs and sodium acetate was released
compared to sediments amended with only sodium acetate (3.49 mg·L–1). Based on molecular fingerprinting and sequencing
analyses, the NP additions could potentially change the sediment bacterial
community composition and increase the abundance of Fe(III) and As(V)
reduction bacteria. Several potential NP-stimulated bacteria were
related to Geobacter, Anaeromyxobacter, Clostridium, and Alicyclobacillus. The findings offer a relatively comprehensive assessment of NP
(e.g., Fe2O3, Fe3O4, and
SiO2) effects on sediment bacterial communities and As
mobilization.