Effects of aluminium oxide nanoparticles on bacterial growth

Warsaw University of Technology, Faculty of Building Services, Hydro and Environmental Engineering, Department of Biology, Nowowiejska 20, 00-653 Warsaw, Poland

^* Corresponding author: nina.doskocz@pw.edu.pl

Abstract

Production and wide application of nanomaterials have led to nanotechnology development but their release to environment and the induction of toxic reactions, affects the natural microbial communities. Therefore, studies on the impact of nanoparticles on microorganisms and environment are required and needed. The aim of this study was to assess the impact of aluminium oxide nanoparticles on the growth of Pseudomonas putida. To compare the harmfulness of different forms of aluminium oxide, the ecotoxicity of its macro-forms was also evaluated in the study. Research showed that the exposure to nanoparticles can negatively influence microorganisms. The EC₅₀-16h determined in this study was 0.5 mg/l, and NOEC equaled 0.19 mg/l. Nano-Al₂O₃ proved to be more toxic to P. putida than aluminium oxide. This indicates that the nano-form of a given substance demonstrates different properties and may constitute a far greater danger for the environment than the same substance in the large form. According to EU and US EPA criteria, nano-Al₂O₃ proved to be very toxic and highly toxic, respectively. Changes in bacterial communities caused by nanoparticles may affect the normal biological, chemical and nutrient cycle in the ecosystem and the effect triggered by nanomaterials in relation to other organisms is unpredictable.