Dramatic enhancement of solar disinfection (SODIS) of wild Salmonella sp. in PET bottles by H2O2 addition on natural water of Burkina Faso containing dissolved iron

Abstract

Disinfection of surface water containing dissolved iron (0.3 mg L1 ) at natural neutral pH (7.5) was carried out via solar disinfection (SODIS) treatment in PET bottles with H2O2 (10 mg L1 ). Wild coliforms and Salmonella sp. were monitored for 6 h of sunlight irradiation and 72 h of dark post-treatment period. In our conditions, SODIS treatment could not avoid Salmonella sp. re-growth during dark storage, meanwhile the addition of 10 mg L1 of H2O2 showed a strong enhancement of the inactivation rate without any re-growth of both bacteria. Finally, total coliforms (Escherichia coli included) demonstrated to be an inappropriate indicator for monitoring bacterial contamination in water during solar disinfection processes.