Bacterial toxicity comparison between nano- and micro-scaled oxide particles

• Published in: Environmental pollution (1987) Vol. 157; no. 5; pp. 1619 - 1625
• Main Authors: Jiang, Wei, Mashayekhi, Hamid, Xing, Baoshan
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.05.2009; Elsevier
• Subjects: aluminum oxide; Animal, plant and microbial ecology; Applied ecology; Bacillus subtilis; Bacillus subtilis - drug effects; Biological and medical sciences; Bulk particles; Ecology - methods; Ecotoxicology, biological effects of pollution; Escherichia coli; Escherichia coli - drug effects; Fundamental and applied biological sciences. Psychology; General aspects; Metal Nanoparticles - toxicity; Microbes; Microbial Sensitivity Tests; Microscopy, Electron, Transmission; mortality; Nanoparticles; nanotechnology; Oxides; Particle Size; pollutants; Pseudomonas fluorescens; Pseudomonas fluorescens - drug effects; silicon; titanium dioxide; Toxicity; zinc oxide; Nanoparticles; Bulk particles; Oxides; Toxicity; Microbes; Ecotoxicology; Nanoparticle; Ultrafine particle; Aerosols; Bacteria; Environment; Air pollution; Toxidty
• ISSN: 0269-7491; 1873-6424
• DOI: 10.1016/j.envpol.2008.12.025

Toxicity of nano-scaled aluminum, silicon, titanium and zinc oxides to bacteria ( Bacillus subtilis, Escherichia coli and Pseudomonas fluorescens) was examined and compared to that of their respective bulk (micro-scaled) counterparts. All nanoparticles but titanium oxide showed higher toxicity (at 20 mg/L) than their bulk counterparts. Toxicity of released metal ions was differentiated from that of the oxide particles. ZnO was the most toxic among the three nanoparticles, causing 100% mortality to the three tested bacteria. Al 2O 3 nanoparticles had a mortality rate of 57% to B. subtilis, 36% to E. coli, and 70% to P. fuorescens. SiO 2 nanoparticles killed 40% of B. subtilis, 58% of E. coli, and 70% of P. fluorescens. TEM images showed attachment of nanoparticles to the bacteria, suggesting that the toxicity was affected by bacterial attachment. Bacterial responses to nanoparticles were different from their bulk counterparts; hence nanoparticle toxicity mechanisms need to be studied thoroughly. Oxide nanoparticles show higher toxicity than their bulk counterparts