Toxicity Study of TiO₂, ZnO and CNT Nanomaterials

Abstract

Nanotechnology based industry is expected to turn into a one trillion dollar industry as their applications are emerged in various fields like consumer products, medicine, and the environment. Rapid development of Nanosciences, therefore, resulted in significant synthesis of various inorganic and organic Nanomaterials followed by their characterization which are highly applicable globally. However, potential negative effects of this burgeoning industry were not well studied, especially toxicity of nanoparticle on aquatic environments. Present study reports the cytotoxicity of Carbon Nanotubes, ZnO nanoparticle and TiO₂ nanoparticle to Chlorella sp. algae. Nanoparticles suspensions were prepared in various concentrations from 0.03 to 0.12 g/l using algal test medium and further quantified by UV/Vis spectroscopy. Algal cultures were maintained in 3–4 K Lux cool white fluorescent light on 16 h/8 h alternate light and dark cycles at 28 ± 2 °C temperature. A growth study of algae was done by measuring the transmittances of algal cultures on 680 nm wavelength at different time interval. It has been observed that with the increase of the concentrations nanoparticles, the growth of algae decreases simultaneously. It shows 90 % growth in presence of CNT’s, 86 % growth in presence of TiO2 and 38 % growth in presence of ZnO nanoparticles as compare to control i.e. 100 %. Reduce growth of Chlorella cells in presence of CNT, TiO2 and ZnO nanoparticles indicates clearly cytotoxicity of these nanoparticles. In our study we found ZnO 62 % toxic, TiO2 14 % toxic and CNT 10 % toxic against Chlorella sp.