SYNERGISTIC EFFECT OF UV IRRADIATION AND SILVER IONS IN THE DISINFECTION OF COLIPHAGE MS2 AND BACILLUS SUBTILIS SPORES

UV irradiation offers rapid, effective disinfection of a range of pathogenic organisms, but does not produce a lasting residual to protect against microbial activity over time and distance from the treatment system. Silver ions are also toxic to pathogens, but generally require a longer contact time to have a significant effect. However, silver ions do produce a lasting effect, and so convey efficacy beyond the instant or physical setting of the treatment system. In assessing the possibility of combining these technologies to merge the advantages of each into a single system, it was found that a synergistic effect was realized, whereby the sum of the levels of inactivation achieved independently by the two technologies was exceeded by the two when acting together.