The Efficacy of Treated Water from Water Filtration Machines for Safe Drinking Water Supply in Bandar Baru Bangi and Kajang, Selangor

Abstract

This study was conducted to determine the physicochemical properties, microbiological quality, level of consumption, and effects of treated water from paid water filtration machines on health of the residents of Bandar Baru Bangi and Kajang, Selangor. The number of water samples taken for this study was 15 from the paid water filtration machines studied. The physicochemical assessment such as determination of pH, turbidity, total dissolved solids, conductivity, and dissolved oxygen was conducted, while the inductively coupled plasma mass spectrometry (ICP-MS) was used to determine the mineral content of the treated water. The microbiological quality was determined using the pour plate method for colony count (22°C incubation for 72 hours and 37°C for 24 hours), while for coliforms and Escherichia coli, the membrane filtration method was utilized. The samples of treated water from the paid water filters were based on triplicate sampling (n = 3). The pH, turbidity, total dissolved solid values, and heavy metal concentration were within the safe level according to the Malaysian National Standard for Drinking Water Quality, Ministry of Health (MOH). The overall range for the pH values of the treated water samples was between 6.50 and 7.15, where this was within the recommended range. The total dissolved solids showed that all the treated water samples were in the range of the recommended standard (27 to 92 mg/L). The range of turbidity values for all the treated water samples was from 1.7 to 6 NTU, and the dissolved oxygen range was from 7.7 to 8.2 mg/L. The colony count results showed that most of the water samples complied with the standards of <4 log cfu/mL at 37°C and <3 log cfu/mL at 22°C of incubation temperatures. However, there was the presence of coliforms in four (4/15) of the treated water samples being at more than 4 cfu/100 mL, while E. coli was absent in all of the treated water samples. The overall results showed that all samples were safe to drink according to the Industrial Guide to Good Hygiene Practice by Automatic Vending Association of Britain (2000) and Food Act (1983) except for the four treated water samples (C, D, H, and I). For that reason, the filtered waters require quality evaluation and management, while the filters need to be replaced according to their designated schedule in order to ascertain that the drinking water is safe to be consumed by the public.