Levels and proportions of free fluoride and soluble fluorine in different brands of toothpaste / 中华地方病学杂志

ABSTRACT

Objective To investigate the level and proportional relationship of free fluorine and soluble fluoride in different brands of toothpaste,and analyze possible risk factors.Methods A total of 54 samples of commercially available toothpastes of domestic,joint venture and imported in Guiyang City were collected,and the levels of free fluoride and soluble fluorine were determined,respectively,using fluorideion selective electrode.method (GB 8372-2008).Results The number of the toothpaste was 32,12,10,respectively,in domestic,joint venture and imported.The levels of free fluorine ranged from 0.98 to 1 603.50 mg/kg,3.22 to 617.50 mg/kg and 306.80 to 1 590.80 mg/kg,respectively,in toothpastes of domestic,joint venture and imported; the number of exceeding the standard free fluorine was 3,0 and 1,respectively,in toothpastes of domestic,joint venture and imported; the rate of exceeding the standard free fluorine was 9.4％,0.0％ and 10.0％,respectively,in toothpastes of domestic,joint venture and imported.The levels of soluble fluorine ranged from 3.06 to 4 302.50 mg/kg,9.02 to 1 667.30 mg/kg and 9.18 to 4 013.20 mg/kg,respectively,in toothpastes of domestic,joint venture and imported; the number of exceeding the standard soluble fluorine was 9,2 and 3,respectively,in toothpastes of domestic,joint venture and imported; the rate of exceeding the standard soluble fluorine was 34.4％,16.7％ and 30.0％,respectively,in toothpastes of domestic,joint venture and imported.The proportion of free fluorine and soluble fluoride wasdomestic 1.0 ∶ 2.7,joint venture 1.0 ∶ 2.7,imported 1.0 ∶ 2.5,respectively.The confidence limit (R/d) was 0.98.Conclusion The fluoride level in different brands of toothpaste has exceeded the standard,the content and proportion of soluble fluoride are obviously higher than those of free fluoride,and there is a risk on tooth damage from fluoride,and factories should strengthen quality control in adding fluoride.