Department of Civil and Environmental Engineering, University of Alberta, Edmonton, AB, T6G 2W2, Canada.
Institute for Environmental Genomics, Department of Microbiology and Plant Biology, University of Oklahoma, Norman, OK, USA.
J Hazard Mater. 2018 Jan 5;341:448-456. doi: 10.1016/j.jhazmat.2017.07.051. Epub 2017 Aug 2.
Increased amount of nano-silver will be released into domestic and industrial waste streams due to its extensive application. However, great controversy still exists on the effects of silver nanoparticle (Ag-NP) on biological wastewater treatment processes and a toxicology model has not been built yet. Four sequencing batch reactors with activated sludge has been run for over three months with different silver species at a concentration of 1mg Ag/L in influent. Both freshly prepared Ag-NPs and aged Ag-NPs were tested with released silver ion as control. Results in this study showed that Ag-NPs, especially freshly prepared Ag-NPs, can help to maintain or even increase the diversity of microbial community in activated sludge and the biomass concentration even under long-term treatment. It indicates that the hormesis model need to be considered for the toxicology of Ag-NPs.
由于纳米银的广泛应用，其将被更多地释放到生活污水和工业废水中。然而，纳米银颗粒（Ag-NP）对生物废水处理过程的影响仍存在很大争议，并且尚未建立毒理学模型。在进水银浓度为 1mg/L 的条件下，用不同的银物种连续运行了四个带有活性污泥的序批式生物膜反应器超过三个月。以新鲜制备的 Ag-NP 和老化的 Ag-NP 作为对照，测试了释放出的银离子。本研究结果表明，Ag-NP，尤其是新鲜制备的 Ag-NP，可有助于维持甚至增加活性污泥中微生物群落的多样性，即使在长期处理下，生物量浓度也会增加。这表明在 Ag-NP 的毒理学方面需要考虑到激素效应模型。
