Water Res. 2011 Dec 31.
Solar water disinfection (SODIS) of Escherichiacoli, Enterococcus spp., and MS2 coliphage: Effects of additives and alternative container materials.
Fisher MB, Iriarte M, Nelson KL. Department of Civil and Environmental Engineering, University of California, Berkeley, CA 94720-1710, USA.
The use of alternative container materials and added oxidants accelerated the inactivation of MS2 coliphage and Escherichiacoli and Enterococcus spp. bacteria during solar water disinfection (SODIS) trials. Specifically, bottles made from polypropylene copolymer (PPCO), a partially UVB-transparent plastic, resulted in three-log inactivation of these organisms in approximately half the time required for disinfection in bottles made from PET, polycarbonate, or Tritan(®), which absorb most UVB light.
Furthermore, the addition of 125 mg/L sodium percarbonate in combination with either citric acid or copper plus ascorbate tended to accelerate inactivation by factors of 1.4-19. Finally, it was observed that the inactivation of E. coli and enterococci derived from local wastewater was far slower than the inactivation of laboratory-cultured E. coli and Enterococcus spp., while the inactivation of MS2 was slowest of all.
These results highlight the importance of UVB in SODIS under certain conditions, and also the greater sunlight resistance of some viruses and of bacteria of fecal origin, as compared to the laboratory-cultured bacteria commonly used to model their inactivation. Furthermore, this study illustrates promising new avenues for accelerating the inactivation of bacteria and viruses by solar disinfection.
