The status of microbiological contamination of water using to produce bottled drinking water in Khanh Hoa province in 2022

Ninety-three samples of source water, used to produce bottled drinking water at bottled drinking water producers in Khanh Hoa province in 2022, were examined for microbiological criteria such as coliform, Escherichia coli, Pseudomonas aeruginosa, and HPC (Heterotrophic Plate Count). Results indicated that 19/93 (20.4%) of samples did not meet the microbiological requirements according to QCVN 01-1:2018/BYT. In which, the percentage of microbiological unsatisfactory well water (42.9%, 6/14) was higher than that of tap water (16.5%, 13/79). The proportion of source water samples of bottled drinking water facilities that did not meet the microbiological requirements in Cam Lam district (83.3%) was higher than those of Cam Ranh (33.3%), Dien Khanh (30%), Ninh Hoa (13.6%), Nha Trang (8%), and Van Ninh (7.7%). Unsatisfactory microbiological criteria included coliform (16.1%), P. aeruginosa (15.1%), and E. coli (1.1%). In addition, there were 8/93 (8.6%) samples with HPC higher than the recommended limit (500 CFU/mL) of the Environmental Protection Agency (EPA). The means of HPC, coliform, and P. aeruginosa were 4,2 × 102, 6,2 × 101, and 1,1 × 102 CFU/100 mL, respectively. Contaminated source water is one of the risks of microbiological contamination in finished bottled drinking water. Therefore, bottled drinking water producers in Khanh Hoa need to maintain good infection control and minimize the risk of microbial contamination from source water to finished bottled drinking water.