Quantitative Microbiological Risk Assessment of Salmonella spp. in Drinking Water in Sealed Container

Quantitative Microbial Risk Assessment of Salmonella spp. in Bottled Water

Abstract

         Salmonella spp. are pathogens of serious public health concern as they cause food poisoning in humans. The objective of this study was to quantitatively evaluate the risks associated with Salmonella contamination of consumable bottled water in 15 randomly selected provinces of Thailand between October 2020 and September 2021. The study revealed that one out of a total of 346 samples was positive for Salmonella. The prevalence of Salmonella contamination was 0.29%, while the concentration of Salmonella was 0.01 CFU/mL. The amount of water to be consumed per day was 2.151 L, and the number of exposed microorganisms was 21.51 CFU. The response to dose assessment showed the risk or probability of illness at 0.0000108 and 0.0452, as estimated by the exponential model and the beta-Poisson model, respectively. Based on the dose-response assessment model, at the concentration of microbial exposure of at least 10 CFU/mL, the probability of illness was 0.02324. The exposure assessment showed the probability of exposure to Salmonella at 0.00289. Thus, the risks of illness due to drinking bottled water contaminated with Salmonella were 0.000000031 and 0.000130619 according to the exponential model and the beta-Poisson model, respectively. The quantitative microbial risk assessment revealed that the bottled water consumption in the study area was within acceptable and safe risk criteria. This study approach could be used as a prototype for microbiological risk assessments and applicable to other food types or pathogenic microorganisms.