Inactivation and regrowth of antibiotic-resistant bacteria by PAA disinfection in the secondary effluent of a municipal wastewater treatment plant

Biomed Environ Sci. 2013 Oct;26(10):865-8. doi: 10.3967/bes2013.012.

Abstract

Inactivation and microbial regrowth of penicillin-, ampicillin-, cefalexin-, tetracycline-, chloramphenicol-, and rifampicin-resistant bacteria were studied to explore risks associated with selection and regrowth of antibiotic-resistant bacteria after PAA disinfection. The results showed that after exposure to 20 mg/L PAA for 10 min, inactivation of ampicillin-resistant bacteria reached 2.3-log, which was significantly higher than that of total heterotrophic bacteria with a decrease of 2.0-log. In contrast, inactivation of tetracycline- resistant bacteria was significantly less efficient, reaching only 1.1-log. Chloramphenicol-and tetracycline-resistant bacteria, as well as total heterotrophic bacteria regrew more than 10 fold compared to those in the untreated wastewater sample with 22 h stilling culture after exposure to 2 or 5 mg/L PAA as for 10 min. Selection and potential regrowth of tetracycline-and chloramphenicol-resistant bacteria are potential risks when utilizing PAA disinfection, which may induce the spread of specific antibiotic-resistant bacteria in reclaimed water.

Publication types

  • Letter
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anti-Bacterial Agents / pharmacology
  • Bacteria / drug effects
  • Disinfection*
  • Waste Disposal, Fluid
  • Wastewater*
  • Water Microbiology
  • Water Purification

Substances

  • Anti-Bacterial Agents
  • Waste Water