Laboratory investigation of the microbiological performance of ceramic water filters as household water treatment technology

Ceramic Water Filter (CWF) is a widespread household water treatment (HWT) technology in urban and rural areas of developing countries like Bangladesh. However, information regarding the microbiological performance of CWF is rare. A 23 weeks study was undertaken aiming to evaluate the microbiological performance of commercially available CWFs in Bangladesh under laboratory controlled environment according to WHO protocol. A total of 24 filters from three well-known brands were purchased and the removal performance of E.coli bacteria, MS-2 bacteriophage virus and Clostridium perfringens spores were evaluated using two types of challenged waters. Results showed that filter performance declined with the increasing filtration period. The filters were found moderately effective but inconsistent in reducing E.coli (1.03–2.15 log
10
reduction), MS2 (0.52–1.52 log
10
reduction) and less effective against C. perfringens spores (0.50–1.06 log
10
reduction). Also the devices can effectively reduce turbidity (> 98% removal) and color (> 90% removal). In complying WHO guideline, only one brand achieved protective target in few cases. The findings of this study is very much to a study in Cambodia, however more scientific performance data is needed to confirm its reliability.