Bioaccumulation of C-13-fullerenol nanomaterials in wheat

Fullerenol, an important water-soluble derivative of fullerene carbon nanomaterial, has been increasingly used in medicine and industry. The presence and release of carbon nanoparticles into the environment have raised concerns over potential impacts on human health and the environment. In this study, the bioaccumulation of fullerenol nanoparticles in wheat was investigated using C-13-labelling techniques. The dose and time-dependent bioaccumulation of fullerenol in wheat was observed, and most fullerenol (about 85.68-263.86% ID per g, percentage of dose per gram tissue) was found in roots. With prolonged culture times, the seedlings treated with relatively low concentrations of fullerenol nanoparticles (2.5 mu g mL(-1)) showed significant increases in C-13 content in roots, while 10.0 mu g mL(-1) fullerenol appeared to suppress this accumulation. Only very limited amounts (< 4.13% ID per g) of fullerenol nanoparticles were translocated from roots to stems and leaves. The presence of fullerenol nanoparticles was confirmed by scanning electron microscopy, and small particles were found in the vascular cylinder of wheat roots. During the incubations with fullerenol nanoparticles at all test concentrations, the biomass gain of stems and leaves was unaffected, while root elongation was promoted. Fullerenol also improved the synthesis of chlorophyll in wheat during the 7 d observation period.