Antimicrobial effects of bleaching agents: Part 1: Studies on Escherichia coli ATCC 11229 and Enterococcus faecium ATCC 6057

In low temperature washing processes (i.e. < 40°C) inactivation of microorganisms cannot be achieved solely by temperature effects as in 60°C-processes. Many detergents, however, contain bleaching systems which inactivate microorganisms by oxidation thus resulting in adequate hygiene even at lower temperatures. In this study the bacterial efficacy of bleaching agents (sodium perborate monohydrate, sodium percarbonate) and a bleaching activator (TAED) was examined using the standard suspension test method with selected bacteria (Entc. faecium, E. coli). The effect of pH on the biocidal efficiency of bleaching agents was also tested. The results showed that bleaching agents in concentrations as used in detergents can significantly contribute to the inactivation of faecal bacteria even at low temperatures and that the efficacy of the bleaching agents is considerably affected by other parameters such as pH-conditions and soiling.