Comparative Responses to Metal Oxide Nanoparticles

Authors: Alexandra CastroBugallo África GonzálezFernández Cástor Guisande Aldo Barreiro

Publish Date: 2014/06/08

Volume: 67, Issue: 4, Pages: 483-493

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Abstract

A series of experiments was undertaken on three different marine microalgae to compare the effect of two metal oxide nanoparticles NPs on different physiological responses to stress zinc oxide ZnO a known toxic compound for microalgae and the never before tested yttrium oxide Y2O3 The effect of these potential pollutants was estimated for different physiological variables and temporal scales Growth carbon content carbontonitrogen CN ratio and chlorophyll fluorescence were evaluated in longterm assays and reactive oxygen species ROS production was evaluated in a shortterm assay Population growth was the most susceptible variable to the acute toxic effects of both NPs as measured in terms of number of cells and of biomass Although Phaeodactylum tricornutum and Alexandrium minutum were negatively affected by ZnO NPs this effect was not detected in Tetraselmis suecica in which cell growth was significantly decreased by Y2O3 NPs Biomass per cell was negatively affected in the most toxic treatments in T suecica but was positively affected in A minutum ZnO treatments induced a sharper decrease in chlorophyll fluorescence and higher ROS than did Y2O3 treatments The pronounced differences observed in the responses between the species and the physiological variables tested highlight the importance of analyzing diverse groups of microalgae and various physiological levels to determine the potential effects of environmental pollutantsWe thank Tamara Lozano and Mercedes Peleteiro for advice on flow cytometry The research leading to these results has received funding from the European Union Seventh Framework Programme FP7NMPSMALL2 and FP7/REGPOT201220131 under grant agreements HINAMOX228825 and BIOCAPS316265 respectively

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