The short-term toxic effects of TiO2 nanoparticles toward bacteria through viability, cellular respiration, and lipid peroxidation

Erdem A., Metzler D., Cha D. K., Huang C. P.

ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH, vol.22, no.22, pp.17917-17924, 2015 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 22 Issue: 22
  • Publication Date: 2015
  • Doi Number: 10.1007/s11356-015-5018-1
  • Journal Name: ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.17917-17924
  • Keywords: TiO2 nanoparticles, E. coli, B. subtilis, Cell inactivation, Lipid peroxidation, Cellular respiration disruption, ESCHERICHIA-COLI, TITANIUM-DIOXIDE, PHOTOCATALYTIC DISINFECTION, INACTIVATION, WATER, STERILIZATION, IRRADIATION, MECHANISM, SYSTEM, HEALTH
  • Akdeniz University Affiliated: Yes

Abstract

To better understand the potential impacts of metal oxide nanoparticles (NPs) on Gram(+) Bacillus subtilis and Gram(-) Escherichia coli (K12) bacteria, eight different nanosized titanium dioxide (TiO2) suspensions with five different concentrations were used. Water quality parameters (pH, temperature, and ionic strength), light sources, and light intensities were also changed to achieve different environmental conditions. The photosensitive TiO2 NPs were found to be harmful to varying degrees under ambient conditions, with antibacterial activity increasing with primary particle sizes from 16 to 20 nm. The presence of light was a significant factor under most conditions tested, presumably due to its role in promoting generation of reactive oxygen species (ROS). However, bacterial growth inhibition was also observed under dark conditions and different water quality parameters, indicating that undetermined mechanisms additional to photocatalytic ROS production were responsible for toxicity. The results also indicated that nano-TiO2 particles in the absence and the presence of photoactivation induced lipid peroxidation and cellular respiration disruption.