AWWA WQTC71345

Bacterial regrowth is a concern for many water treatment facilities. Previous studies showed that extracellular polymeric substances (EPS) play a role in bacterial resistance to disinfectants. In this study, strains from an opportunistic pathogen, Pseudomonas aeruginosa (both wild type and mutant strains) with different EPS secretion capabilities were tested to monitor the role of EPS on the susceptibility of bacteria to three disinfectants (chlorine, chloramines, and chlorine dioxide). The mucA strain, which overproduces EPS, showed high resistance to all three disinfectants than the other two strains, which produce less or no EPS. The results indicated that cell bound EPS reacted with disinfectants and decreased the susceptibility of bacteria cells. Includes 13 references, tables, figures.