Toothpaste with nano HA was conducted according to the adsorption of lead ions in synthetic wastewater. Comparisons were made between distinct particle sizes of nano HA based on the adsorption effect of lead ions. Meanwhile

the stability of adsorption and mechanism of nano HA toothpaste was investigated. The suspensions of nano HA

HA dentifrice and blank dentifrice with different concentrations were prepared．Lead ion solutions with initial concentration of 1.0 mg /L were mixed with these suspensions respectively. Following being kept still for 24 h

14 d and 28 d

the residual lead ion concentration of the supernatant was measured

the sorption rate and sorption ability was calculated. The result showed that the nano HA and nano HA dentifrice with various particle sizes had strong abilities of absorbing lead ions from simulated waste water

the average adsorption rate was determined to be 95%. The adsorption capacity of nano HA increased with the decrease of particle sizes. The adsorption capacity of nano HA dentifrice was significantly higher than that of the micro HA dentifrice and blank dentifrice. The effects of nano HA dentifrice group on Pb

2+

 adsorption were relatively stable

of which no desorption were detected subsequently. Both Langmuir and Freundlich equations were sued to simulate the sorption processes of the nano HA and HA dentifrice. The result indicated that the dentifrice containing nano HA could reduce the lead ions effectively，and could be used as an environmental protection absorbent

which is beneficial to giving environmental significance for the daily health caring behavior.