Adriana Zaleska (UG) in National Institute for Environmental Studies (NIES) in Tsukuba

Between 15 and 29 of June I was visiting National Institute for Environmental Studies in Tsukuba (Japan) within Work Package 2: Carrying out experiments to produce necessary (missing) data for nanoparticles. Four series of TiO₂ based nanoparticles was prepared by members of my research group and they will be systematically characterized to collect data regarding surface properties (including crystal structure, BET surface area, morphology and surface content) and toxicity. Based on obtained experimental data, computational model will be developed to evaluate environmental risk of TiO₂-based nanoparticles.

TiO₂ nanoparticles are the most researched photocatalytic material, because it provides the most efficient photocatalytic activity, the highest stability and the lowest cost. Pure and modified TiO₂ is used both for degradation of organic and inorganic compounds in aqueous solutions and to remove microorganisms, e.g. in water and wastewater treatment and disinfection processes (Advanced Oxidation Technologies). Thus, TiO₂ nanoparticles could be released to aqueous environment and affect organisms due to three potential mechanisms: (a) transport of nanoparticles via cell membrane; (b) release of metal ions from doped of modified TiO₂ (noble and transient metals); or (c) formation of active oxygen species at irradiated TiO₂ surface.

During my visit, procedure of toxicity measurements for TiO₂-based nanocomposites was discussed and developed.