<  Back to the Polytechnique Montréal portal

Impacts of Continuous Inflow of Low Concentrations of Silver Nanoparticles on Biological Performance and Microbial Communities of Aerobic Heterotrophic Wastewater Biofilm

Sanaz Alizadeh, Arshath Abdul Rahim, Bing Guo, Jalal Hawari, Subhasis Ghoshal and Yves Comeau

Article (2019)

Open Access document in PolyPublie
Open Access to the full text of this document
Accepted Version
Terms of Use: All rights reserved
Download (710kB)
Show abstract
Hide abstract


Attached-growth wastewater processes are currently used in water resource recovery facilities (WRRFs) for required upgrades due to an increase in influent loading or to reach more stringent discharge criteria. Yet, the distribution and long-term inhibitory effects of silver nanoparticles (AgNPs) in attached-growth biological wastewater processes and their impact on involved microbial communities are poorly understood at relevant, low concentrations. Retention, distribution, and long-term inhibitory effect of polyvinylpyrrolidone (PVP)-coated AgNPs were evaluated in bench-scale moving bed biofilm reactors (MBBRs), achieving soluble organic matter removal, over a 64 day exposure to nominal concentrations of 10 and 100 μg/L. Distributions of continuously added AgNPs were characterized in the influent, bioreactor, and effluent of MBBRs using single particle inductively coupled plasma mass spectroscopy (spICP-MS). Aerobic heterotrophic biofilms in MBBRs demonstrated limited retention capacity for AgNPs over long-term exposure, with release of AgNPs, and Ag-rich biofilm sloughed from the carriers. Continuous exposure to both influent AgNP concentrations significantly decreased soluble chemical oxygen demand (SCOD) removal efficiency (11% to 31%) and reduced biofilm viability (8% to 30%). Specific activities of both intracellular dehydrogenase (DHA) and extracellular α-glucosidase (α-Glu) and protease (PRO) enzymes were significantly inhibited (8% to 39%) with an observed NP dose-dependent intracellular reactive oxygen species (ROS) production and shift in biofilm microbial community composition by day 64. Our results indicated that long-term exposure to AgNPs in biofilm processes at environmentally relevant concentrations can impact the treatment process stability and the quality of the discharged effluent.

Uncontrolled Keywords

Biofilms, Metal nanoparticles, Peptides and proteins, Wastewater, Biomass

Subjects: 1000 Civil engineering > 1000 Civil engineering
1000 Civil engineering > 1006 Hydrologic engineering
1000 Civil engineering > 1007 Water resources and supply
Department: Department of Civil, Geological and Mining Engineering
Funders: CRSNG/NSERC, Environment and Climate Change Canada, PerkinElmer, Health Sciences Canada, Fonds de Recherche du Québec Nature et Technologies (FRQNT), Canadian Water Network (CWN), SNC Lavalin Environment, City of Calgary, City of Saint-Hyacinthe
Grant number: STPGP 430659–12
PolyPublie URL: https://publications.polymtl.ca/9089/
Journal Title: Environmental Science & Technology (vol. 53, no. 15)
Publisher: ACS Publications
DOI: 10.1021/acs.est.9b01214
Official URL: https://doi.org/10.1021/acs.est.9b01214
Date Deposited: 16 Aug 2021 13:11
Last Modified: 13 May 2023 00:21
Cite in APA 7: Alizadeh, S., Abdul Rahim, A., Guo, B., Hawari, J., Ghoshal, S., & Comeau, Y. (2019). Impacts of Continuous Inflow of Low Concentrations of Silver Nanoparticles on Biological Performance and Microbial Communities of Aerobic Heterotrophic Wastewater Biofilm. Environmental Science & Technology, 53(15), 9148-9159. https://doi.org/10.1021/acs.est.9b01214


Total downloads

Downloads per month in the last year

Origin of downloads


Repository Staff Only

View Item View Item