Engineered nanoparticles have been extensively used in electronics, energy, materials and biomedical areas. Engineered nanoparticles with unique magnetic, luminescent, and catalytic properties can not only benefit human society, but also cause potentially harmful interactions with living systems. This study was aimed at assessing the cytotoxicity of CuO ENPs, TiO2ENPs, CeO2ENPs, SWCNTs in human lung epithelial cell line (A549). Herein, we performed a comprehensive study on the cytotoxicity of four different ENPs by examining the viability of A549 cells. The results showed that CuO ENPs could cause a highest dose-dependent cytotoxicity, SWCNTs were more toxic than TiO2ENPs and CeO2ENPs to A549 cells, TiO2ENPs induced a slight loss of cell viability at 100 mg/L and CeO2ENPs had no obvious cytotoxicity. These effects were dose related, and should be considered in the application of different areas of ENPs.

The emerging use of metal oxide engineered nanoparticles has given rise to concerns about their potential impact on the environment. Nanoparticles will inevitably enter water environment, while there is little data on aquatic plants which play an important role in aquatic ecosystems. The inhibitory effect of copper oxide engineered nanoparticles (CuO ENPs) on the growth of aquatic plant Lemna minor was evaluated. Results showed that inhibition of plant growth was significant after exposed to CuO ENPs at the concentration of 150 μg/L. The inhibitory effect of CuO ENPs on frond number was similar to dry weight and total surface area. It is clear that CuO ENPs cause a potential risk to aquatic plants and therefore ecosystems.