低氟砖茶预防大鼠砖茶型氟中毒的实验观察

目的 观察低氟砖茶预防砖茶型氟中毒的效果。方法 用低氟砖茶（含氟量210．0mg/kg）和普通砖茶（含氟量503．5mg/kg）制备的茶水喂饲Wistar大鼠，在4，8，12个月时观察动物的日总摄氟量，茶氟在动物体内的代谢情况和氟中毒情况。结果 普通砖茶组动物在0．3mg左右的日总摄氟量时，8个月开始出现以棕、白横纹为主的氟斑牙，12个月后发展为以白垩为主的氟斑牙，患病率达75．0％。低氟砖茶组动物日总摄氟量0．19mg，实验期间未出现氟中毒症状。氟代谢观察表明，半量茶氟通过尿、粪便排出体外，体内吸收的氟绝大部分进入骨骼。结论 低氟砖茶能有效预防砖茶型氟中毒。

Prevention of brick-tea fluorosis in rats with low-fluoride brick-tea on laboratory observation

Objective To test whether the low fluoride bric-tea can prevent the occurrence of fluorosis.Methods Rats had access to a specially prepared low fluoride brick tea (210.0 mg/kg) and ordinary brick tea (503.0 mg/kg) for one year.The daily fluoride intake,fluoride metabolism,tissue distribution and development of dental fluorosis were observed at the end of months 4,8 and 12,respectively.Results The daily intake of fluoride in the ordinary brick-tea group was 0.3 mg,and they developed dental fluorosis characterized as brown and white horizontal markers at the end of month 8,and white chalk dental fluorosis developed at the end of month 12.The total incidence was 75%.In contrast,the daily fluoride intake of the low fluoride brick-tea group was 0.19 mg,and this group did not develop any signs of dental fluorosis.Fluoride distribution was mainly retained in the bone tissue,and about half of the absorbed fluoride was excreted via urine and feces.Conclusions The results suggest that this low level fluoride brick tea did not induce fluorosis in rats and can be used as an effective control measure for humans.