Journal
ENVIRONMENTAL SCIENCE & TECHNOLOGY
Volume 55, Issue 13, Pages 9221-9230Publisher
AMER CHEMICAL SOC
DOI: 10.1021/acs.est.1c00645
Keywords
the UV/chlorine process; chlorine radicals; pathogens; viable but nonculturable cells; disinfection; reactivation
Categories
Funding
- Natural Science Foundation of China [21922612, U2005206, 41861144023, 22076225]
- Fundamental Research Funds for the Central Universities in China [20lgjc02, 20lgpy94]
Ask authors/readers for more resources
The UV/chlorine process effectively reduced the number of culturable cells in drinking water disinfection, eliminated viable but nonculturable bacteria, and showed better metabolic activity. Additionally, it successfully suppressed bacterial dark reactivation.
UV irradiation and chlorination have been widely used for water disinfection. However, there are some limitations, such as the risk of generating viable but nonculturable bacteria and bacteria reactivation when using UV irradiation or chlorination alone. This study comprehensively evaluated the feasibility of the UV/chlorine process in drinking water disinfection, and Pseudomonas aeruginosa was selected as the target microorganism. The number of culturable cells was effectively reduced by more than 5 orders of magnitude (5-log(10)) after UV, chlorine, and UV/chlorine treatments. However, intact and VBNC cells were detected at 10(3) to 10(4) cells/mL after UV and chlorine treatments, whereas they were undetectable after UV/chlorine treatment due to the primary contribution of reactive chlorine species (Cl-center dot, Cl-2(center dot-), and ClO center dot). After UV/chlorine treatment, the metabolic activity determined using single cell Raman spectroscopy was much lower than that after UV. The level of toxic opr gene in P. aeruginosa decreased by more than 99% after UV/chlorine treatment. Importantly, bacterial dark reactivation was completely suppressed by UV/chlorine treatment but not UV or chlorination. This study suggests that the UV/chlorine treatment can completely damage bacteria and is promising for pathogen inactivation to overcome the limitations of UV and chlorine treatments alone.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available