Chen L, Shi H, Medema G, van der Meer W, Liu G. Water Research, 281, 2025, 123566.
Highlights:
- There is limited understanding of long-term and dynamic effects of free chlorine (FC) and monochloramine (MC) on biofilm development.
- A 56-week study was conducted to assess biofilm development under different disinfection regimes: no chlorine (NC), FC (0.1 mg/L), and MC (0.4 mg/L).
- FC and MC significantly inhibited biofilm growth compared to NC.
- FC drastically reduced biofilm biomass and community diversity, resulting in a more uniform biofilm community.
- MC effectively reduced the biofilm biomass to a level comparable to that of FC, however it maintained a high diversity comparable to that of NC.
- The biofilm communities across all disinfection conditions began similarly. However, from week-19 and week-36 under FC and NC the biofilm stabilised. In contrast, the biofilm under MC did not achieve stability until week-56.
- This study challenges classical views that MC is more effective than FC in penetrating and controlling biofilm.
