Abstract: Though it has been claimed that nanotechnology has great potential in environmental cleaning, caution is required to the application of nano-particles (<100 nm). The studies relevant to organism exposure have shown that nano-particles can be hazardous. Currently, more papers are available about the remediation efficiency, characteristics, and mechanisms of manufactured nano-particles after applied into polluted environment, but  few studies are conducted about the ecotoxicological effects of the nano-particles. This paper reviewed the current researches on the hazards of nano- or ultrafine particles in environmental detoxification, discussed the potential environmental risks of applying nano-particles, and prospected the perspectives of the nanoparticles in environmental cleaning research.

Key words: nanoscale materials, toxicity, environmental risk, remediation