Activated sludge and UV-C₂₅₄ for Sapovirus, Aichivirus, Astrovirus, and Adenovirus processing

ABSTRACT

In this study, the detection rates of four enteric viruses, Human Astrovirus (HAstVs), Aichivirus (AiVs), Human Adenovirus (HAdVs), and Sapovirus (SaVs) are carried out to assess the virological quality of the treated wastewater. A total of 140 samples was collected from wastewater treatment plant WWTP of Tunis-City. Real-time RT-PCR and conventional RT-PCR results showed high frequencies of detection of the four enteric viruses investigated at the entry and exit of the biological activated sludge procedure and a significant reduction in viral titers after tertiary treatment with UV-C254 irradiation. These results revealed the ineffectiveness of the biological activated sludge treatment in removing viruses and the poor quality of the treated wastewater intended for recycling, agricultural reuse, and safe discharge into the natural environment. The UV-C254 irradiation, selected while considering the non-release of known disinfection by-products because of eventual reactions with the large organic and mineral load commonly present in the wastewater.

KEYWORDS:

• Sapovirus
• Aichivirus
• Astrovirus and Adenovirus
• wastewater
• activated sludge
• UV-C₂₅₄

Acknowledgements

All authors thank all those who have contributed to this important work, in particular the staff of the pilot station El Menzeh 1 and the National Reference Center of Enteric Viruses (Dijon, France).

Disclosure 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.

Author’s contribution

All authors contributed to the study’s conception and design. CI and PP performed the conventional RT-PCR and the qRT-PCR optimization, analysis, and data interpretation. CI wrote the first draft of the manuscript. NK achieved all physico-chemical and bacteriological analyses. AH and SH conceptualized the project supervised the work, and all authors commented on earlier versions of the manuscript. All authors read and approved the final submitted manuscript.

Data availability statement

The datasets supporting the conclusions of this article are included within the article.

Additional information

Funding

This study was funded by the CERTE (Techno Park of Borj-Cédria, Tunisia) and the National Reference Center of Enteric Viruses (Dijon, France).