Removal of antibiotic microbial resistance by micro- and ultrafiltration of secondary wastewater effluents at pilot scale

• Published in: The Science of the total environment 2022-09, Vol.838 (Pt 2), p.156052-156052, Article 156052
• Main Authors: Hiller, Christian X., Schwaller, Christoph, Wurzbacher, Christian, Drewes, Jörg E.
• Format: Article
• Language: English
• Subjects: 16S rRNA gene, total cell counts; Antibiotic resistance genes; Microfiltration; Standard filtration mode; Ultrafiltration
• ISSN: 0048-9697; 1879-1026
• DOI: 10.1016/j.scitotenv.2022.156052

Low-pressure membrane filtration was investigated at pilot scale with regard to its removal of antimicrobial resistance genes (ARGs) in conventional secondary treated wastewater plant effluents. While operating microfiltration (MF) and ultrafiltration (UF) membranes, key operational parameters for antimicrobial resistance (AMR) studies and key factors influencing AMR removal efficiencies of low-pressure membrane filtration processes were examined. The main factor for AMR removal was the pore size of the membrane. The formation of the fouling layer on capillary membranes had only a small additive effect on intra- and extrachromosomal ARG removal and a significant additive effect on mobile ARG removal. Using feeds with different ARGs abundances revealed that higher ARG abundance in the feed resulted in higher ARG abundance in the filtrate. Live-Dead cell counting in UF filtrate showed intact bacteria breaking through the UF membrane. Strong correlations between 16S rRNA genes (as surrogate for bacteria quantification) and the sul1 gene in UF filtrate indicated ARBs likely breaking through UF membranes. [Display omitted] •Removal of antibiotic microbial resistance by micro- and ultrafiltration•Fouling layer on capillary membranes have only a small additive effect on removal.•Higher ARG abundance in the feed result in higher ARG abundance in filtrate.•Strong correlations between 16S rRNA genes and sul1 gene in UF filtrate