Influence of soil type and environmental conditions on ZnO, TiO2 and Ni nanoparticles phytotoxicity

Abstract

Intensive development of nanotechnology will result in releasing nanoparticles (NPs) to the environment including soil. The objective of the study was the evaluation of phytotoxicity of inorganic nanoparticles and their bulk counterparts (ZnO, TiO2 and Ni) in various soils using Phytotoxkit F™ method. The estimation of toxicity was conducted with relation to Lepidium sativum. The toxicity of NPs was also estimated in relation to contact time between NPs and soil, effect of light and temperature and NPs–NPs interactions. In all tested variants no effect of NPs on seed germination was observed. NPs displayed varied effect on inhibition of plant root growth in relation to soil type. Only in the case of ZnO nanoparticles and their bulk counterparts a dose–effect relationship was observed. That relationship, however, was observed only in OECD soil. In a majority of cases, aging and increase of temperature caused a reduction of toxicity of NPs, while light conditions increased the toxic effect of NPs. The effect of the NPs interaction: ZnO with TiO2 or Ni had an antagonistic character, that was manifested in a reduction of the toxicity of ZnO.