Does the Process for Production Nanoparticulate ZnO Play a Role in its Ecotoxicity?

Abstract

Abstract:The interaction between live organisms and nanosized particles has become a current focus in toxicology. The aims of the present work are: (i) to assess the zinc oxide (ZnO) toxicity and its mechanisms into the aquatic environment, using the green algae Chlorella vulgaris as biological indicator; (ii) to compare the ZnO behavior and toxic profile in synthetic (Bold's Basal) and natural (Seine River Water, SRW) culture media; and (iii) to address whether the obtaining route is an issue in ZnO particles toxicity or not. Responses such as growth inhibition, cell viability, superoxide dismutase (SOD) activity, adenosine-5-triphosphate (ATP) content and photosynthetic efficiency were evaluated. The main conclusions are: (i) nanoparticulate ZnO have an statistically significant toxic effect on C. vulgaris growth since the lower concentration tested (1ppm), that seems to be mediated by a induced oxidative stress (probably due to extensive release of Zn 2+ into the media); (ii) the ZnO behavior in synthetic and natural culture media were statistically similar, although the toxic effects were more pronounced in SRW; and (iii) the production process does not seem to be an issue in ZnO nanoparticles toxicity since all tested particles produced significant effects on microalgae growth