scholarly journals Recent Update on UV Disinfection to Fulfill the Disinfection Credit Value for Enteric Viruses in Water

Author(s):  
Nicolas Augsburger ◽  
Andri Taruna Rachmadi ◽  
Noor Zaouri ◽  
Yunho Lee ◽  
Pei-Ying Hong
2019 ◽  
Vol 17 (5) ◽  
pp. 670-682 ◽  
Author(s):  
Albert Simhon ◽  
Vince Pileggi ◽  
Cecily A. Flemming ◽  
José R. Bicudo ◽  
George Lai ◽  
...  

Abstract In Ontario, Canada, information is lacking on chlorine and ultraviolet (UV) light disinfection performance against enteric viruses in wastewater. We enumerated enteroviruses and noroviruses, coliphages, and Escherichia coli per USEPA methods 1615, 1602, and membrane filtration, respectively, in pre- and post-disinfection effluent at five wastewater treatment plants (WWTPs), with full-year monthly sampling, and calculated log10 reductions (LRs) while WWTPs complied with their monthly geometric mean limit of 200 E. coli/100 mL. Modeling of densities by left-censored estimation and Bayesian inference gave very similar results. Polymerase chain reaction (PCR)-detected enteroviruses and noroviruses were abundant in post-disinfection effluent (mean concentrations of 2.1 × 10+4–7.2 × 10+5 and 2.7 × 10+4–3.6 × 10+5 gene copies (GC)/L, respectively). Chlorine or UV disinfection produced modest LRs for culture- (0.3–0.9) and PCR-detected enteroviruses (0.3–1.3), as well as noroviruses GI + GII (0.5–0.8). Coliphages and E. coli were more susceptible, with LRs of 0.8–3.0 and 2.5, respectively. Sand-filtered effluent produced significantly higher enteric virus LRs (except cultured enteroviruses). Coliphage and human enteric virus densities gave significantly positive correlations using Kendall's Tau test. Enteric viruses are abundant in wastewater effluent following routine chlorine or UV disinfection processes that target E. coli. Coliphages appear to be good indicators for evaluating wastewater disinfection of enteric viruses.


Author(s):  
G. C. Smith ◽  
R. L. Heberling ◽  
S. S. Kalter

A number of viral agents are recognized as and suspected of causing the clinical condition “gastroenteritis.” In our attempts to establish an animal model for studies of this entity, we have been examining the nonhuman primate to ascertain what viruses may be found in the intestinal tract of “normal” animals as well as animals with diarrhea. Several virus types including coronavirus, adenovirus, herpesvirus, and picornavirus (Table I) were detected in our colony; however, rotavirus, astrovirus, and calicivirus have not yet been observed. Fecal specimens were prepared for electron microscopy by procedures reported previously.


2002 ◽  
Vol 2 (3) ◽  
pp. 23-28 ◽  
Author(s):  
C.-H. von Bonsdorff ◽  
L. Maunula ◽  
R.M. Niemi ◽  
R. Rimhanen-Finne ◽  
M.-L. Hänninen ◽  
...  

The purpose of this study was to monitor the levels of human enteric viruses and enteric protozoa and to relate their presence to the microbes used as hygienic quality indicators in domestic sewage from a small community in Finland during a period of one year. Genome-based sensitive detection methods for the pathogens selected (astro- and Norwalk-like viruses, Giardia and Cryptosporidium) have become available only recently and thus no earlier data was available. The effluent sewage is delivered into a river that serves as raw water for a larger town and the pathogens therefore constitute a health risk. The results showed that all the monitored pathogens could be detected, and that enteric viruses were present at considerable concentrations in sewage. High concentrations of astrovirus in raw sewage were observed during a diarrhea epidemic in the local day-care centre. The presence of viruses did not correlate with the monitored bacterial indicators of faecal contamination (coliforms, E. coli and enterococci) or with bacteriophages (somatic coliphages, F-specific RNA phages and B. fragilis phages). Giardia cysts and Cryptosporidium oocysts were detected from one sample (1/10) each.


2002 ◽  
Vol 2 (3) ◽  
pp. 17-22
Author(s):  
A.P. Wyn-Jones ◽  
J. Watkins ◽  
C. Francis ◽  
M. Laverick ◽  
J. Sellwood

Two rural spring drinking water supplies were studied for their enteric virus levels. In one, serving about 30 dwellings, the water was chlorinated before distribution; in the other, which served a dairy and six dwellings the water was not treated. Samples of treated (40 l) and untreated (20 l) water were taken under normal and heavy rainfall conditions over a six weeks period and concentrated by adsorption/elution and organic flocculation. Infectious enterovirus in concentrates was detected in liquid culture and enumerated by plaque assay, both in BGM cells, and concentrates were also analysed by RT-PCR. Viruses were found in both raw water supplies. Rural supplies need to be analysed for viruses as well as bacterial and protozoan pathogens if the full microbial hazard is to be determined.


2008 ◽  
Vol 8 (2) ◽  
pp. 217-222 ◽  
Author(s):  
Beibei Zhu Sun ◽  
Ernest Blatchley ◽  
Mike Oliver ◽  
Cheng Zheng ◽  
Kristofer Jennings

The effects of foulant chemical composition on ultraviolet (UV) absorbance of fouled quartz sleeves in UV disinfection systems were studied. Statistical analysis was conducted to examine the effects of nine fouling chemicals on the UV transmittance changes of fouled quartz lamp sleeves. The results demonstrated that the main effects were attributable to surface concentrations of iron and manganese. The surface concentrations of calcium and copper had no significant effects on the UV absorbance of fouled sleeves. The interaction effects of copper with iron and magnesium with manganese were also revealed from the statistical analysis. The model is able to give reasonable predictions of the UV absorbance characteristics of foulants from other UV systems. However, several limitations of this model were identified. First, the model does not accurately predict the absorbance at relatively high chemical surface concentrations. Second, the model does not account for the possible effects of anions and organics on UV absorption of fouled quartz sleeves.


1983 ◽  
Vol 15 (5) ◽  
pp. 129-135 ◽  
Author(s):  
Z Filip ◽  
K Seidel ◽  
H Dizer

To determine whether long-term sewage treatment can take place without a pollution risk for soil and groundwater, samples from sewage irrigation fields in West Berlin which have been in use since about 1890 were analyzed for enteric viruses and microorganisms. Enteric viruses were detected in only seven samples from a total number of eighty seven taken from different soil depths. With only one exception, no viruses were found below 60 cm. No viruses were detected in groundwater samples. Long-term sewage irrigation did not result in significant changes in the colony courts of aerobic soil bacteria, but the counts of anaerobic bacteria and actinomycetes were slightly elevated and those of microscopic fungi slightly decreased. Potentially pathogenic bacteria were not detected in soil below 90 cm.


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