Otěrové částice z brzdového obložení automobilů a jejich akutní akvatická toxicita pro sladkovodní zelené řasy

Abstract

Kučová, K.: Automotive brake wear particles and their acute aquatic toxicity to fre-shwater green algae. Ostrava, VŠB – Technical University of Ostrava, University Study Programmes, 2014, Thesis supervisor: Doc. Mgr. Jana Kukutschová, Ph.D. The bachelor thesis deals with an experimental evaluation of potential impact of non-airborne fraction of wear particles generated by automotive braking to the environment, especially to growth of freshwater green algae (Desmodesmus subspicatus a Raphidocelis subcapitata). Scanning electron microscopy (SEM) and Raman micro-spectroscopy were used to analyze elemental and phase composition of wear particles generated from a model automotive friction composite and captured from the environ-mental chamber of laboratory dynamometer as a settled fraction. SEM of water extract of wear particles revealed a release of nano-sized particles from the non-airborne fracti-on into the liquid phase. Both experimental techniques utilized showed decent hetero-geneous character of wear debris and also the water extract, which could affect linear course of the dose-response relationship in the acute aquatic toxicity bioassay. Based on the obtained experimental data it can be stated that the non-airborne fraction of wear particles has a potency to interact with cells of the detection organisms, which was ma-nifested by growth inhibition of Raphidocelis subcapitata cells. However, Desmodesmus subspicatus was observed to be stimulated in its growth.