Comparison of Bacterial Count in Tap Water between First Burst and Running Tap Water
Talabporn Harnroongroj PhD*, Amornrat Leelaporn MD**, Sunee Limsrivanichayakorn MSc**, Srirumpha Kaewdaeng MSc**, Thossart Harnroongroj MD, PhD***
Affiliation : * Department of Tropical Nutrition and Food Science, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand ** Department of Microbiology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand *** Department of Orthopaedic Surgery, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
Objective : To compare the number of bacterial counts in tap water at first burst and running tap water.
Material and Method: The present study was performed in thirty-two first burst water samples and twenty-nine running tap
water samples after two minutes, collected from an operation room at one standard hospital and analyzed for the mean,
median, and 95% achieved confidence interval of CFU/ml. All water samples were cultured and investigated for total
bacterial counts, which were expressed as colony forming unit per milliliter (CFU/ml).
Results : The bacterial count was statistically significantly about three times higher in the samples of the first burst tap water
in comparison with the group of samples after letting the tap water run for two minutes 98.7, 78.5, 60.5-120.0 vs. 29.1, 25.8,
16.6-33.2 CFU/ml.
Conclusion : Two minutes running tap water contains about three times less bacterial count than first burst tap water.
Keywords : Tap water, First burst tap water, Running tap water, Bacterial count, Water contamination
