SINOUVASSANE DJEARAMANE, LING SHING WONG, YANG MOOI LIM AND POH FOONG LEE
Abstract
Nano particles such as zinc oxide nano particles (ZnO NPs) have a wide range of applications in industrial and personal care products, but, at the same time, the presence of nano particles causes negative impact to aquatic ecosystem and the organisms within. In this study, the cytotoxic effect of ZnO NPs on fresh water microalga Chlorella vulgaris is reported. C. vulgaris cells were treatedwith 10, 50, 100, 150 and 200 mg/L of ZnO NPs for 72 h. Cytotoxicity effects of ZnO NPs were assessed by measuring the fluorescence emission of chlorophyll using fluorescents pectrophotometer, algal biomass by spectrophotometer and cell viability through counting viablecells at 24, 48 and 72 h. Exposure to ZnO NPs caused a decrease in chlorophyll content, cell viability and algal biomass. The cytotoxic effects increased as the concentration and exposure duration of ZnO NPs increased. Toxicity of ZnO NPs was indicated by reduction in the chlorophyll content,cell viability and biomass. This study showed the potential of C. vulgaris to be a bio indicator forZnO NPs'toxicity in aquatic environment.