A Survey on coliform contamination and chemical parameters of potable water from water dispensers in faculties of Mashhad University of Medical Sciences

Water is of great significance for living and access to safe water has been considered as an important goal in public health. However, water can transmit a wide range of pathogenic microorganisms. The aim of this study was to determine the bacteriological quality of drinking water dispensed by water coolers from different faculties of Mashhad University of Medical Sciences, on August 2016. A total of 22 samples from 9 water coolers of different faculties of Mashhad University of Medical Sciences were collected and some indicators of contamination including total coliform and fecal coliform, residual free chlorine and pH were evaluated. Results show that Coliform and Escherichia coli were not observed in any of the water samples. Residual chlorine content in drinking water in 50 percent of samples and pH in 12.5 percent of samples were out of Iranian standard levels range. There is no significant difference between the levels of pH and chlorine in water samples before and after water dispenser systems. The lack of coliform indicates the safety of drinking water from water coolers. However, the decrease in the residual free chlorine after water cooler may cause to grow some microorganisms in water coolers. Therefore, it is suggested that an appropriate and regular monitoring program should be established.