Lawrence Berkeley National Laboratory
Contradictory effects of silver nanoparticles on activated sludge wastewater treatment.
- Author(s): Sheng, Zhiya
- Van Nostrand, Joy D
- Zhou, Jizhong
- Liu, Yang
- et al.
Published Web Locationhttps://doi.org/10.1016/j.jhazmat.2017.07.051
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.