E. coli and bacteriophage MS2 disinfection by UV, ozone and the combined UV and ozone processes

Abstract

The combination of low-dose ozone with ultraviolet (UV) irradiation should be an option to give benefit to disinfection and reduce drawbacks of UV and ozone disinfection. However, less is known about the disinfection performance of UV and ozone (UV/ozone) coexposure and sequential UV-followed-by-ozone (UV-ozone) and ozone-followed-by-UV (ozone-UV) exposures. In this study, inactivation of E. coli and bacteriophage MS2 by UV, ozone, UV/ozone coexposure, and sequential UV-ozone and ozone-UV exposures was investigated and compared. Synergistic effects of 0.5–0.9 log kill on E. coli inactivation, including increases in the rate and efficiency, were observed after the UV/ozone coexposure at ozone concentrations as low as 0.05 mg·L^-1 in ultrapure water. The coexposure with 0.02-mg·L^-1 ozone did not enhance the inactivation but repressed E. coli photoreactivation. Little enhancement on E. coli inactivation was found after the sequential UV-ozone or ozone-UV exposures. The synergistic effect on MS2 inactivation was less significant after the UV/ozone coexposure, and more significant after the sequential ozone-UV and UV-ozone exposures, which was 0.2 log kill for the former and 0.8 log kill for the latter two processes, at ozone dose of 0.1 mg·L^-1 and UV dose of 8.55 mJ·cm^-2 in ultrapure water. The synergistic effects on disinfection were also observed in tap water. These results show that the combination of UV and low-dose ozone is a promising technology for securing microbiological quality of water.

Keywords

bacteria inactivation / photoreactivation / water disinfection / UV / ozone

References

[1] FawellJ, RobinsonD, BullR, BirnbaumL, BoormanG, ButterworthB, DanielP, Galal-GorchevH, HauchmanF, JulkunenP, KlaassenC, KrasnerS, Orme-ZavaletaJ, ReifJ, TardiffR. Disinfection by-products in drinking water: critical issues in health effects research. Environmental Health Perspectives, 1997, 105(1): 108–109

[2] Mac KenzieW R, HoxieN J, ProctorM E, GradusM S, BlairK A, PetersonD E, KazmierczakJ J, AddissD G, FoxK R, RoseJ B, DavisJ P. A massive outbreak in Milwaukee of cryptosporidium infection transmitted through the public water supply. The New England Journal of Medicine, 1994, 331(3): 161–167

[3] LindenK G, ShinG A, FaubertG, CairnsW, SobseyM D. UV disinfection of Giardia lamblia cysts in water. Environmental Science & Technology, 2002, 36(11): 2519–2522

[4] ShinG A, LindenK G, ArrowoodM J, SobseyM D. Low-pressure UV inactivation and DNA repair potential of Cryptosporidium parvum oocysts. Applied and Environmental Microbiology, 2001, 67(7): 3029–3032

[5] von GuntenU. Ozonation of drinking water: part II.Disinfection and by-product formation in presence of bromide, iodide or chlorine. Water Research, 2003, 37(7): 1469–1487

[6] JungY J, OhB S, KangJ W. Synergistic effect of sequential or combined use of ozone and UV radiation for the disinfection of Bacillus subtilis spores. Water Research, 2008, 42(6–7): 1613–1621

[7] LabatiukC W, BelosevicM, FinchG R. Inactivation of Giardia-muris using ozone and ozone-hydrogen peroxide. Ozone Science and Engineering, 1994, 16(1): 67–78

[8] MeunierL, CanonicaS, von GuntenU. Implications of sequential use of UV and ozone for drinking water quality. Water Research, 2006, 40(9): 1864–1876

[9] WangX, HuX, WangH, HuC. Synergistic effect of the sequential use of UV irradiation and chlorine to disinfect reclaimed water. Water Research, 2012, 46(4): 1225–1232

[10] WalkerG C. Mutagenesis and inducible responses to deoxyribonucleic acid damage in Escherichia coli. Microbiological Reviews, 1984, 48(1): 60–93

[11] FriedbergE C, WalkerG C, SiedeW. DNA Repair and Mutagenesised. Washington, D C: ASM Press, 1995

[12] ReiszE, SchmidtW, SchuchmannH P, von SonntagC. Photolysis of ozone in aqueous solutions in the presence of tertiary butanol. Environmental Science & Technology, 2003, 37(9): 1941–1948

[13] von SonntagC. The Chemical Basis of Radiation Biology. London: Taylor & Francis, 1987

[14] WolfeR L, StewartM H, ScottK N, McGuireM J. Inactivation of Giardia-muris and indicator organisms seeded in surface-water supplies by peroxone and ozone. Environmental Science & Technology, 1989, 23(6): 744–745

[15] ChoM, ChungH, ChoiW, YoonJ. Linear correlation between inactivation of E. coli and OH radical concentration in TiO₂ photocatalytic disinfection. Water Research, 2004, 38(4): 1069–1077

[16] ShangC, CheungL M, HoC M, ZengM Z. Repression of photoreactivation and dark repair of coliform bacteria by TiO₂-modified UV-C disinfection. Applied Catalysis B: Environmental, 2009, 89(3–4): 536–542

[17] APHA-AWWA-WEF. Standard Methods for the Examination of Water and Wastewater. 20th ed. Washington, D C, USA: American Public Health Association/American Water Works Association/Water Environment Federation, 1998

[18] ShangC, CheungL M, LiuW. MS2 coliphage inactivation with UV irradiation and free chlorine/monochloramine. Environmental Engineering Science, 2007, 24(9): 1321–1332

[19] USEPA. Method 1602: Male-Specific (F+) and Somatic Coliphage in Water by Single Agar Layer (SAL) Procedureed. Washington, D C: United States Environmental Protection Agency, 2001

[20] RahnR O. Potassium iodide as a chemical actinometer for 254 nm radiation: use of iodate as an electron scavenger. Photochemistry and Photobiology, 1997, 66(4): 450–455

Acknowledgements

We acknowledge the financial support from the National Natural Science Foundation of China (Grant No. 51108117) and the Hong Kong Innovation and Technology Fund (No. ITS/336/09).

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2014 Higher Education Press and Springer-Verlag Berlin Heidelberg