Microbial risk assessment of drinking water filtration dispenser toll machines (DFTMs) in Mahasarakham province of Thailand

Abstract

This investigation aimed to assess the microbial quality of drinking water produced by drinking water filtration dispenser toll machines (DFTMs) to assess the health risk of DFTM water. A total of 210 samples were randomly collected of 70 DFTMs within a radial distance of 500 metres around Mahasarakham University. The prevalence of Escherichia coli and Staphylococcus aureus in the DFTM water was 54.17% and 16.67% with an average concentration of 1.04 log cfu/ml and 0.26 log cfu/ml, respectively. The risk calculation (using the @Risk program based on drinking water consumption of 2 L/day) indicated that the probability of exposure was 1.67 E-01, while the probability of illness due to E. coli and S. aureus was 2.08 E-03 and 1.58 E-05 and the risk of illness was 1.13 E-03 and 2.64 E-06, respectively. The sanitation status and drinking water quality related to health would be influenced by other pathogens due to the poor hygienic conditions of DFTMs and improper environments.

Drinking water quality assessment from water dispensers in an educational institution

“…Ten out of 60 samples tested for the presence of total coliform bacteria (16.67%) and five out of 60 samples tested for fecal coliform bacteria (8.33%) were found unsatisfactory concerning microbiological quality. E. coli could not be detected in any sample, a finding in accordance with similar studies recently conducted (Pratum & Khananthai 2017;Yongyod 2018;Wibuloutai et al 2019). The absence of these microorganisms, considered to represent an indicator of fecal contamination, renders water quality satisfactory and safe without health concerns.…”

“…However, previous investigations found that 76.6% of examined dispensers were contaminated with fecal coliform microbes, Escherichia coli, fecal streptococci, Pseudomonas aeruginosa or Staphylococcus spp. and revealed a prevalence of E. coli and S. aureus in filtration-treated dispenser water of 54.17% and 16.67%, respectively (da Silva et al 2008;Wibuloutai et al 2019). In particular, levels of E. coli and S. aureus are frequently monitored as indicators of the hygienic status of drinking water (Jessen et al 2013).…”

“…In particular, levels of E. coli and S. aureus are frequently monitored as indicators of the hygienic status of drinking water (Jessen et al 2013). The Thailand Department of Health had recently reported that an estimated 40% of vending machines did not provide drinking water whose quality met the standard requirements (Wibuloutai et al 2019). Consequently, unwanted changes in the microbial quality of drinking water can have adverse effects on the distribution system and consumers (Prest et al 2016).…”

Bacteriological Quality of Drinking Water and Hygienic Assessment of Water Cooler Dispensers in Higher Education Institution

“…[ 7 16 23 ] The low level of E. coli in this study might show the low risk of illness from E. coli exposure as described in the previous quantitative microbial risk assessment (QMRA) of drinking water in Mahasarakham province of Thailand. [ 23 ] In addition, E. coli detected in drinking water can be implied that pathogenic bacteria, viruses, and parasites may also be contaminated.…”

Coliform contamination on faucet surface of water vending machines in Klang Valley

“…Routine maintenance with effective sanitisation of all outer and inner surfaces is crucial [45] . We would like to highlight the stressing needs for proper sanitisation on the contact points between users and water vending machines for the persistent hygienic issues [46][47][48] .…”