F-Specific RNA Bacteriophages as Model Viruses in UV Disinfection of Wastewater

Abstract

F-specific RNA (FRNA) bacteriophages can be assayed in wastewater by simple and rapid methods. Their inactivation by UV radiation follows first-order kinetics and relatively simple formulas can describe the effect of UV absorbance by wastewater and the wavelength-dependent killing efficiency of polychromatic lamps. Because the organisms can be grown in high concentrations, biological calibration of full-scale reactors requires only relatively small volumes of phage culture. Naturally occurring FRNA-phages were more resistant to UV than somatic coliphages, Escherichiacoli and faecal streptococci. The inactivation rate constant was almost equal to that of reoviruses, which underlines the suitability of FRNA-phages as a process indicator for UV inactivation of viruses. A pure culture of MS2 was inactivated at a rate which was almost twice that of naturally occurring FRNA-phages, indicating the necessity of designing reactors for practical applications on field-data rather than laboratory experiments.