Abstract: OBJECTIVE: To establish the early warning of the contamination of nano-SiO₂ particle,swimming behavior changes of zebrafish under nano-SiO₂ particle exposure were studied. METHODS: Based on behavior response of zebrafish,effects of nano-SiO₂particles,including individual endpoints(swimming speed,swimming depth,turning frequency and acceleration) and group endpoints(distance and dispersion),were investigated by using Online Bio monitoring. RESULTS: Swimming behavior changes of zebrafish were affected significantly in 600 and 1200 mg/L exposure dose groups. Swimming speed was decreased 30%-50% 6 h after exposure. Changes of swimming depth lagged behind changes of swimming speed,which were decreased by more than 90% 24 h after exposure. Group behavior of zebrafish was also changed,distance and dispersion were significantly decreased(all P<0.01). CONCLUSION: After exposure,swimming behavior of zebrafish(swimming speed,swimming depth,turning frequency,distance and dispersion) were affected significantly wie increase of nano-SiO₂ particles concentration,which is consistend wie Stepwise Stress Model.

Key words: nano-SiO₂ particles, zebrafish, behavior, biological monitoring