Research On Drinking Safety Of Fluorine In The Hunan Brick Tea

Brick tea as a kind of tea was not only popular to Tibet, Mongolia, Xinjiang, Sichuang, Qinghai, Ningxia, Gansu etc. but also to people all over the world. But in recent years, it was reported that some Tibetans in China got fluorosis by long-term excessive fluoride intake, mainly from brick tea, which has been attached importance to this problem by so mang people. This research are mainly about the condition which brick tea release the least fluoride; make certain the best drink way for people at different altitude; prepare the drinking water according to the daily way for rats then copy the fluorosis type rats, make sure the subsidiary things can make different affections to the fluorosis or not; find out which nutriention can help reduce the dissociative fluoride under the manmade gastric and enteric juice.The fluoride content in tea infusion is about 70.94%—83.37%of the total fluoride in brick tea with an average of 76.91%. The smaller of the ratio between teas to water, fluoride extracted increased at first, and then decreased. When the ratio reached 1:100, people will absorb the fluoride more than the safe level, but at 1:150 the infusion amount was lower than the safe lever. Fluoride release was significantly negatively linear-correlated with the infusing times (p<0.05),60.53% of the total fluoride can be avoide taking in if discard first tea soup. The release of fluoride was significantly positively linear-correlated with the infusion time (p<0.05). Control infusion time within 5 minutes can make us take in less fluoride, and totally under 4 mg/day. Fluoride infusion amount reached the Maximum between 70℃—80℃. People may absorb fluoride more than the safe level if the temperature over 60℃.Control tea to water ratio at 1:150 then use blurry math way to do sense estimate. Advice places where boil point is 60℃or 70℃like part of Tibet,Sinkiang ect. Can control the boil time within 30 min, the release amount was at lowest point but the taste were the same. And places where boil point is 80℃suggest boil 20 min, like part of Tibet SiChuang and Sinkiang ect. Boil point at 90℃～100℃,20 min boil time is enough to satisfy the drinker and can be safer, so the places like Qinghai, ningxia, Mongolia ect. Should avoid using long time to boil tea, which is not safe for health.Milk and salt can accelerate the fluoride amount of brick tea soup have been approved. Rats were fed with brick tea infusion (F 100 mg/L) added with salt or milk powder or both for 90 days, respectively. Rats drink tea infusion with both milk powder and salt take in less amount fluoride than drink infusion with milk powder but more fluoride than drink infusion with salt. Blood serum fluoride, bone calcium, growth and weight have no significant difference between groups. Fluoride distribution was mainly retained in the bone tissue, and more than half of the absorbed fluoride was excreted via urine and feces. Rats drink tea infusion with milk powder, infusion with milk powder and salt, infusion with salt developed dental fluorosis characterized as brown and white horizontal marks after 30,35,40 days, respectively. Finally the total dental fluorosis of these three groups was all over 75%. And white chalky dental fluorosis developed in 60 days later.90 days later all groups except tap water group, karyopyknosis cell can be found in the liver cells; renal tubules degeneration; tooth essence was loosen and have cracks, from the paraffin-embedded section of Liver, kidney & teeth.Prepare 50 mL manmade gastric juice and 50 mL manmade enteric juice, and then add 400mL tea soup, separately. Put them in the 37℃water bath. Then add milk powder,salt,salt and milk powder,casein,VC,VE,VD,vegetable tallow,animal oil,lactic acid calcium,VD add with calcium to each of them. During 3 hours, each half hour drop out 50 mL mixture liquid to text the fluoride amount. Compare with manmade gastric juice and tea soup mixture or manmade enteric juice and tea soup mixture, the fluoride amount increase when the mixture was added with milk powder salt,salt and milk powder vegetable tallow,animal oil during this 3 hours. But when adding casein,VC,VE,VD,lactic acid calcium,VD add with calcium, the fluoride amount decrease. Although during 1 to 1.5 hour the VC and lactic acid calcium briefly accelerate the fluoride release amount of the tea soup, totally reduce the fluoride release amount.