TY - JOUR
T1 - Removal of human pathogenic viruses in a down-flow hanging sponge (DHS) reactor treating municipal wastewater and health risks associated with utilization of the effluent for agricultural irrigation
AU - Kobayashi, Naohiro
AU - Oshiki, Mamoru
AU - Ito, Toshihiro
AU - Segawa, Takahiro
AU - Hatamoto, Masashi
AU - Kato, Tsuyoshi
AU - Yamaguchi, Takashi
AU - Kubota, Kengo
AU - Takahashi, Masanobu
AU - Iguchi, Akinori
AU - Tagawa, Tadashi
AU - Okubo, Tsutomu
AU - Uemura, Shigeki
AU - Harada, Hideki
AU - Motoyama, Toshiki
AU - Araki, Nobuo
AU - Sano, Daisuke
N1 - Funding Information:
This work was supported by JSPS KAKENHI Grant number 21676004, 25289174, and 26249075 for TY, NA, and DS, respectively, and Program for the Strategic Promotion of International Cooperation to Accelerate Innovation in Developing Countries of Japan Science and Technology Agency.
Publisher Copyright:
© 2016 Elsevier Ltd
PY - 2017
Y1 - 2017
N2 - A down-flow hanging sponge (DHS) reactor has been developed as a cost-effective wastewater treatment system that is adaptable to local conditions in low-income countries. A pilot-scale DHS reactor previously demonstrated stable reduction efficiencies for chemical oxygen demand (COD) and ammonium nitrogen over a year at ambient temperature, but the pathogen reduction efficiency of the DHS reactor has yet to be investigated. In the present study, the reduction efficiency of a pilot-scale DHS reactor fed with municipal wastewater was investigated for 10 types of human pathogenic viruses (norovirus GI, GII and GIV, aichivirus, astrovirus, enterovirus, hepatitis A and E viruses, rotavirus, and sapovirus). DHS influent and effluent were collected weekly or biweekly for 337 days, and concentrations of viral genomes were determined by microfluidic quantitative PCR. Aichivirus, norovirus GI and GII, enterovirus, and sapovirus were frequently detected in DHS influent, and the log10reduction (LR) of these viruses ranged from 1.5 to 3.7. The LR values for aichivirus and norovirus GII were also calculated using a Bayesian estimation model, and the average LR (±standard deviation) values for aichivirus and norovirus GII were estimated to be 1.4 (±1.5) and 1.8 (±2.5), respectively. Quantitative microbial risk assessment was conducted to calculate a threshold reduction level for norovirus GII that would be required for the use of DHS effluent for agricultural irrigation, and it was found that LRs of 2.6 and 3.7 for norovirus GII in the DHS effluent were required in order to not exceed the tolerable burden of disease at 10−4and 10−6disability-adjusted life years loss per person per year, respectively, for 95% of the exposed population during wastewater reuse for irrigation.
AB - A down-flow hanging sponge (DHS) reactor has been developed as a cost-effective wastewater treatment system that is adaptable to local conditions in low-income countries. A pilot-scale DHS reactor previously demonstrated stable reduction efficiencies for chemical oxygen demand (COD) and ammonium nitrogen over a year at ambient temperature, but the pathogen reduction efficiency of the DHS reactor has yet to be investigated. In the present study, the reduction efficiency of a pilot-scale DHS reactor fed with municipal wastewater was investigated for 10 types of human pathogenic viruses (norovirus GI, GII and GIV, aichivirus, astrovirus, enterovirus, hepatitis A and E viruses, rotavirus, and sapovirus). DHS influent and effluent were collected weekly or biweekly for 337 days, and concentrations of viral genomes were determined by microfluidic quantitative PCR. Aichivirus, norovirus GI and GII, enterovirus, and sapovirus were frequently detected in DHS influent, and the log10reduction (LR) of these viruses ranged from 1.5 to 3.7. The LR values for aichivirus and norovirus GII were also calculated using a Bayesian estimation model, and the average LR (±standard deviation) values for aichivirus and norovirus GII were estimated to be 1.4 (±1.5) and 1.8 (±2.5), respectively. Quantitative microbial risk assessment was conducted to calculate a threshold reduction level for norovirus GII that would be required for the use of DHS effluent for agricultural irrigation, and it was found that LRs of 2.6 and 3.7 for norovirus GII in the DHS effluent were required in order to not exceed the tolerable burden of disease at 10−4and 10−6disability-adjusted life years loss per person per year, respectively, for 95% of the exposed population during wastewater reuse for irrigation.
KW - Down-flow hanging sponge reactor
KW - Human pathogenic virus
KW - Logreduction
KW - Microfluidic quantitative PCR
KW - Quantitative microbial risk assessment
KW - Wastewater reclamation and reuse
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UR - http://www.scopus.com/inward/citedby.url?scp=85009386931&partnerID=8YFLogxK
U2 - 10.1016/j.watres.2016.10.054
DO - 10.1016/j.watres.2016.10.054
M3 - Article
C2 - 28038763
AN - SCOPUS:85009386931
SN - 0043-1354
VL - 110
SP - 389
EP - 398
JO - Water Research
JF - Water Research
ER -
