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. 2022 Apr 1:212:118069.
doi: 10.1016/j.watres.2022.118069. Epub 2022 Jan 14.

Reduction and liquid-solid partitioning of SARS-CoV-2 and adenovirus throughout the different stages of a pilot-scale wastewater treatment plant

Maria Fernanda Espinosa  1 , Matthew E Verbyla  2 , Lucas Vassalle  1 , Cintia Leal  1 , Deborah Leroy-Freitas  1 , Elayne Machado  1 , Luyara Fernandes  1 , Alcino Trindade Rosa-Machado  1 , Juliana Calábria  1 , Carlos Chernicharo  1 , César Rossas Mota Filho  3
Affiliations

Reduction and liquid-solid partitioning of SARS-CoV-2 and adenovirus throughout the different stages of a pilot-scale wastewater treatment plant

Maria Fernanda Espinosa et al. Water Res. .

Abstract

Investigating waterborne viruses is of great importance to minimizing risks to public health. Viruses tend to adsorb to sludge particles from wastewater processes by electrostatic and hydrophobic interactions between virus, aquatic matrix, and particle surface. Sludge is often re-used in agriculture; therefore, its evaluation is also of great interest to public health. In the present study, a pilot scale system treating real domestic wastewater from a large city in Brazil was used to evaluate the removal, the overall reduction, and liquid-solid partitioning of human adenovirus (HAdV), the novel coronavirus (SARS-CoV-2) and fecal indicators (F-specific coliphages and E. coli). The system consists of a high-rate algal pond (HRAP) post-treating the effluent of an upflow anaerobic sludge blanket (UASB) reactor. Samples were collected from the influent and effluent of each unit, as well as from the sludge of the UASB and from the microalgae biomass in the HRAP. Pathogens and indicators were quantified by quantitative polymerase chain reaction (qPCR) (for HAdV), qPCR with reverse transcription (RTqPCR) (for SARS-CoV-2), the double agar plaque assay (for coliphages), and the most probable number (MPN) method (for E. coli). The removal and overall reduction of HAdV and SARS-CoV-2 was greater than 1-log10. Almost 60% of remaining SARS-CoV-2 RNA and more than 70% of remaining HAdV DNA left the system in the sludge, demonstrating that both viruses may have affinity for solids. Coliphages showed a much lower affinity to solids, with only 3.7% leaving the system in the sludge. The system performed well in terms of the removal of organic matter and ammoniacal nitrogen, however tertiary treatment would be necessary to provide further pathogen reduction, if the effluent is to be reused in agriculture. To our knowledge, this is the first study that evaluated the reduction and partitioning of SARS-CoV-2 and HAdV through the complete cycle of a wastewater treatment system consisting of a UASB reactor followed by HRAPs.

Keywords: Adenovirus; High-rate algal ponds; SARS-CoV-2; Sewage; Sludge; UASB; Virus removal.

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Conflict of interest statement

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Figures

Image, graphical abstract
Graphical abstract
Fig. 1
Fig. 1
Diagram of the pilot-scale upflow anaerobic sludge blanket (UASB) reactor followed by twin high-rate algal ponds (HRAPs) with return of algal biomass, showing the measured flow rates and sample collection points (1 – 5).
Fig. 2
Fig. 2
Boxplots of the concentrations in raw wastewater, UASB effluent and HRAP effluent, a) SARS-CoV-2 RNA (log copies/mL), b) HAdV DNA (log copies/mL), c) F-specific coliphages (log PFU/mL) and d) E. coli (log MPN/mL). The lower and upper bars denote minimum and maximum values, respectively. The lower and upper boxes represent the 25th and 75th percentiles, respectively. Mean values are represented by an “x”. The line inside the box denotes the median value.
Fig. 3
Fig. 3
Liquid-solid partitioning of the microrganisms throughout the different stages, a) UASB reactor, b) HRAP settler and c) UASB reactor + HRAP.
See this image and copyright information in PMC

References

    1. Ahmed W., Angel N., Edson J., Bibby K., Bivins A., O'Brien J.W., Choi P.M., Kitajima M., Simpson S.L., Li J., Tscharke B., Verhagen R., Smith W.J.M., Zaugg J., Dierens L., Hugenholtz P., Thomas K.v., Mueller J.F. First confirmed detection of SARS-CoV-2 in untreated wastewater in Australia: a proof of concept for the wastewater surveillance of COVID-19 in the community. Sci. Total Environ. 2020;728 doi: 10.1016/j.scitotenv.2020.138764. - DOI - PMC - PubMed
    1. Ahmed W., Bertsch P., Bivins A., Bibby K., Farkas K., Gathercole A., Haramoto E., Gyawali P., Korajkic A., McMinn B.R., Mueller J., Simpson S., Smith W.J.M., Symonds E.M., Thomas K.v., Verhagen R., Kitajima M. Comparison of virus concentration methods for the RT-qPCR-based recovery of murine hepatitis virus, a surrogate for SARS-CoV-2 from untreated wastewater. Sci. Total Environ. 2020;739 doi: 10.1016/j.scitotenv.2020.139960. - DOI - PMC - PubMed
    1. Ali H.A., Yaniv K., Bar-Zeev E., Chaudhury S., Shaga M., Lakkakula S., Ronen Z., Kushmaro A., Nir O. Tracking SARS-CoV-2 RNA through the wastewater treatment process. Environ. Sci. Technol. Water. 2021;1:1161–1167. doi: 10.1101/2020.10.14.20212837. - DOI - PubMed
    1. Allard A. In: Global Water Pathogen Project. Rose J.B., Jiménez-Cisneros B., editors. UNE, Michigan State University; E. Lansing, MI: 2017. Adenoviruses.http://www.waterpathogens.org/book/adenoviruses (J.S Meschke, and R. G. (eds) P. 3V.(Ed.) (Ed.)
    1. APHA SMWW 9224 Detection of coliphages. 2017 doi: 10.2105/SMWW.2882.195. https://doi.org/ - DOI