Jump to main content
Jump to site search


Peracetic acid disinfection kinetics for combined sewer overflows: indicator organisms, antibiotic resistance genes, and microbial community

Author affiliations

Abstract

Combined sewer overflows (CSOs) degrade water quality and end-of-pipe treatment is one potential solution for retrofitting this outdated infrastructure. The goal of this research was to evaluate peracetic acid (PAA) as a disinfectant for CSOs using viability based molecular methods for antibiotic resistance genes (ARGs), indicator organism marker gene BacHum, and 16S rRNA genes. Simulated CSO effluent was prepared using 23–40% wastewater, representing the higher end of the range of wastewater concentrations reported in CSO effluent. PAA residual following disinfection was greatest for samples with the lowest initial COD. Treatment of simulated CSO effluent (23% wastewater) with 100 mg min L−1 PAA (5 mg L−1 PAA, 20 min) was needed to reduce viable cell sul1, tet(G), and BacHum (1.0 ± 0.63–3.2 ± 0.25-log) while 25 to 50 mg min L−1 PAA (5 mg L−1 PAA, 5–10 min) was needed to reduce viable cell loads (0.62 ± 0.56–1.6 ± 0.08-log) in 40% wastewater from a different municipal treatment plant. Increasing contact time after the initial decrease in viable cell gene copies did not significantly improve treatment. A much greater applied Ct of 1200 mg min L−1 PAA (20 mg L−1 PAA, 60 min) was required for significant log reduction of 16S rRNA genes (3.29 ± 0.13-log). No significant losses of mexB were observed during the study. Data were fitted to a Chick–Watson model and resulting inactivation constants for sul1 and tet(G) > BacHum > 16S rRNA. Amplicon sequencing of the 16S rRNA gene indicated the initial viable and total microbial communities were distinct and that treatment with PAA resulted in marked increases of the relative abundance of select phyla, particularly Clostridia which increased by 1–1.5 orders of magnitude. Results confirm that membrane disruption is a mechanism for PAA disinfection and further treatment is needed to reduce total ARGs in CSO effluent.

Graphical abstract: Peracetic acid disinfection kinetics for combined sewer overflows: indicator organisms, antibiotic resistance genes, and microbial community

Back to tab navigation

Supplementary files

Publication details

The article was received on 13 Jun 2017, accepted on 16 Aug 2017 and first published on 17 Aug 2017


Article type: Paper
DOI: 10.1039/C7EW00184C
Citation: Environ. Sci.: Water Res. Technol., 2017, Advance Article
  •   Request permissions

    Peracetic acid disinfection kinetics for combined sewer overflows: indicator organisms, antibiotic resistance genes, and microbial community

    A. Eramo, W. R. Morales Medina and N. L. Fahrenfeld, Environ. Sci.: Water Res. Technol., 2017, Advance Article , DOI: 10.1039/C7EW00184C

Search articles by author

Spotlight

Advertisements