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Published on: June 7, 2017
Control of bacterial contamination of washbasin taps and output water using Ecasol: a one-year study
M A Boyle1, M J O'Donnell, A Miller
1Microbiology Research Unit, Dublin Dental University School and Hospital, University of Dublin, Trinity College Dublin, Dublin, Ireland.
Background:
Contaminated washbasin taps and output water are an important source of bacteria that may cause nosocomial infection. A five-week pretreatment study of hot and cold water from 15 washbasin taps at Dublin Dental Hospital showed consistently heavy contamination by aerobic heterotrophic bacteria: mean bacterial counts of 482.5 [standard deviation (SD) 293] colony-forming units (cfu)/mL and 5022 (SD 4322) cfu/mL, respectively.
Aim:
To minimize microbial contamination of washbasin taps and output water in the long term using the electrochemically generated, pH-neutral disinfectant, Ecasol.
Methods:
Initially, the 15,000-L water tank providing cold and hot water to washbasins, calorifiers and the distribution network were drained and sediment was removed. The system was shock-dosed with Ecasol 100 ppm to eradicate gross contamination and biofilms. Thereafter, tank water was automatically maintained at Ecasol 2.5 ppm prior to distribution. The microbiological quality of water from five sentinel washbasin taps was monitored weekly for 54 weeks using R2A agar.
Findings:
The mean counts for hot, cold, mains and tank water during the 54-week study period were 1 (SD 4) cfu/mL, 2 (SD 4) cfu/mL, 205 (SD 160) cfu/mL and 0 cfu/mL, respectively. Swab samples of 33/40 taps, each tested on three separate occasions, yielded no growth on R2A agar, while five samples yielded <20 cfu/swab and two samples yielded >200 cfu/swab. No detrimental effects due to Ecasol were observed in the water network.
Conclusion:
Ecasol consistently minimized bacterial contamination of washbasin taps and output water in a dental hospital setting.
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