The impact of electrochemical disinfection on Escherichia coli and Legionella pneumophila in tap water.
In order to reduce the risks of Legionnaires' disease, caused by the bacterium Legionella pneumophila, disinfection of tap water systems contaminated with this bacterium is a necessity. This study investigates if electrochemical disinfection is able to eliminate such contamination. Hereto, water spiked with bacteria (10(4)CFU Escherichia coli or L. pneumophila/ml) was passed through an electrolysis cell (direct effect) or bacteria were added to tap water after passage through such disinfection unit (residual effect). The spiked tap water was completely disinfected, during passage through the electrolysis cell, even when only a residual free oxidant concentration of 0.07 mg/l is left (L. pneumophila). The residual effect leads to a complete eradication of cultivable E. coli, if after reaction time at least a free oxidant concentration of 0.08 mg/l is still present. Similar conditions reduce substantially L. pneumophila, but a complete killing is not realised.
Delaedt
Yasmine
Y
Laboratory of Aquatic Ecology, Katholieke Universiteit Leuven, Ch. Deberiotstraat 32, B-3000 Leuven, Belgium. Yasmine.Delaedt@bio.kuleuven.de
Daneels
Arne
A
Declerck
Priscilla
P
Behets
Jonas
J
Ryckeboer
Jaak
J
Peters
Elmar
E
Ollevier
Frans
F
D002713:Chlorine / Q000032:analysis; D017606:Chlorine Compounds / Q000032:analysis; D004203:Disinfection / Q000379:methods*; D004572:Electrolysis / Q000295:instrumentation*; D004926:Escherichia coli / Q000254:growth & development*; D006861:Hydrogen Peroxide / Q000032:analysis; D016952:Legionella pneumophila / Q000254:growth & development*; D016877:Oxidants / Q000032:analysis; D010087:Oxides / Q000032:analysis; D014867:Water / Q000032:analysis; D014871:Water Microbiology; D018508:Water Purification
D017606:Chlorine Compounds; D016877:Oxidants; D010087:Oxides; D014867:Water; D002713:Chlorine; C025109:chlorine dioxide; D006861:Hydrogen Peroxide