Virus Reduction during Advanced Bardenpho and Conventional Wastewater Treatment Processes

Abstract

The present study investigated wastewater treatment for the removal of 11 different virus types (pepper mild mottle virus; Aichi virus; genogroup I, II, and IV noroviruses; enterovirus; sapovirus; group-A rotavirus; adenovirus; and JC and BK polyomaviruses) by two wastewater treatment facilities utilizing advanced Bardenpho technology and compared the results with conventional treatment processes. To our knowledge, this is the first study comparing full-scale treatment processes that all received sewage influent from the same region. The incidence of viruses in wastewater was assessed with respect to absolute abundance, occurrence, and reduction in monthly samples collected throughout a 12 month period in southern Arizona. Samples were concentrated via an electronegative filter method and quantified using TaqMan-based quantitative polymerase chain reaction (qPCR). Results suggest that Plant D, utilizing an advanced Bardenpho process as secondary treatment, effectively reduced pathogenic viruses better than facilities using conventional processes. However, the absence of cell-culture assays did not allow an accurate assessment of infective viruses. On the basis of these data, the Aichi virus is suggested as a conservative viral marker for adequate wastewater treatment, as it most often showed the best correlation coefficients to viral pathogens, was always detected at higher concentrations, and may overestimate the potential virus risk.

Evaluating the fate of bacterial indicators, viral indicators, and viruses in water resource recovery facilities

“…Even though accurate comparisons are difficult due to differences in WRRF processes, the enteric virus pathogen log reductions were similar to the removal rates seen in other studies (Carducci, Battistini, Rovini, & Verani, 2009;Carducci & Verani, 2013;Hewitt, Leonard, Greening, & Lewis, 2011;Katayama et al, 2008;Petrinca et al, 2009;Wen, Tutuka, Keegan, & Jin, 2009). The two WRRFs with higher levels of secondary treatment (WRRFs G & I) had larger log removals than WRRF H; this finding is similar to what was documented in other WRRF comparisons (Rose et al, 2004;Schmitz, Kitajima, Campillo, Gerba, & Pepper, 2016). The total log reductions in enteric viruses over the entire course of the treatment process were more similar to the 2-3 log reduction seen for infectious coliphage indicators than the 3-4 log reduction seen for cultured fecal indicator bacteria, similar to findings described in Dias, Ebdon, andTaylor (2018), McMinn, Ashbolt, et al (2017), Hata et al (2012), and Rose et al (2004).…”

Pepper mild mottle virus as a water quality indicator

“…1). 28,[31][32][33][34][35] These studies reported that PMMoV was detected in almost all untreated wastewater samples with concentrations greater than 10 5 genome copies (GC)/L ( Table 2). One recent study carried out in Costa Rica documented that the specificity of PMMoV qPCR signal was 100% for domestic wastewater, as compared to 94% specificity of a human-specific (HF183) Bacteroides marker.…”

“…37 PMMoV was also detected in most treated wastewater samples with concentrations greater than 10 4 copies/L ( Table 2). 24,28,[31][32][33][34][35]38 The prevalence of PMMoV in wastewater showed little seasonal variations. 11,31,33 PMMoV showed a higher concentration in wastewater than human enteric viruses.…”

Using indicators to assess microbial treatment and disinfection efficacy

“…AiV RNA concentrations in influent and effluent wastewater have been determined to be up to 2.2×10 7 and 1.8×10 4 GC/L, respectively . A recent study by Schmitz et al (2016) compared the removal of 11 different virus types (pepper mild mottle virus (PMMoV); Aichi virus (AiV); Norovirous GI,II,IV; EntV; sapovirus (SaV); group-A rotavirus (ARV); adenovirus (AdV); and JC polyomavirus JCPyV) by two full-scale WWTP utilizing advanced Bardenpho technology (primarily for nitrogen reduction) and compared the results with previously monitored conventional treatment processes at the same WWTP in Southern Arizona (prior to upgrade) (Kitajima et al, 2014). The results revealed which wastewater treatment processes were most proficient at minimizing the incidence of pathogenic viruses in effluent waters intended for reclamation and recycling and which viral markers correlated best with viral pathogens.…”