Motorcycle engine exhaust emissions containing large amounts of organic nanoparticles, while industrial emissions of inorganic nanoparticles easily, these nanoparticles easily enter into body by the respiratory system and skin. In this study, the human respiratory cell lines were exposed to the organic and inorganic nanoparticles to investigate the effects of cell growth. 　　The sol-gel and hydrothermal synthesis method were use to produceTiO2 or SiO2 nanoparticles by different sintering time and temperature. Organic nanoparticles from motorcycle engine exhaust emissions were subpath obtained. In addition, the study has given quantitative output of plastic atomizer and EFI fog generator produces nano-size range of multi-particle size distribution (polydisperse) and single-particle size distribution of aerosol particles. Four respiratory-related cell lines, A549, HEp2, HacaT, BEAS-2B and a non-transformation of NIH/3T3 were used for cell toxicity study. The inorganic nanoparticleTiO2, SiO2 have not serious toxicity for these cel lines. However, the results of MTT assay find that some nanoparticles have a significant effect on cell growth, such asTiO2 and SiO2 on NIH/3T3 cell lines significantly inhibited the growth, 10nm and 50nm ofTiO2 particle have a significant growth inhibition of the BEAS-2B cell lines, and while the diesel exhaust extract filtrate 13 markedly inhibited HEp2 cell growth. The nanoparticles induced cell death by necrosis pathway, not apoptosis, in the annexin V assay. In addition, we found that some nanoparticles would significantly promote cell growth, such as 10nm Organic nanoparticles for A549 and NIH/3T3 and 10nm and 300 nmTiO2 for HacaT and BEAS-2B cells. Most of nanoparticles do not have transformation activity for human respiratory cell lines. 　　Based on the above results, we found that most of the nanoparticles do not cause cell toxicity and only some specific nanoparticles can cause characteristic changes for specific cell lines, while changes including cells inhibition and proliferation phenomenon. In addition, we have design a cell exposure model to prevent aggregation for nanoparticle and make ensure that the cell lines to correctly reflect the effect of nanoparticles.

nano-particle,TiO2, SiO2