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我国地方性氟病的地球化学问题 总被引:18,自引:0,他引:18
Endemic fluorine disease is a chronic fluorine poisoning caused by high level of fluorine in drinking water or foods. Incidence of this disease has been knowu in many parts of the world. In China its occurrence has been observed in the Northeast, Northwest, Southwest and some other localities. Investigation shows that it is closely related to geochemical environment: Major fluorine sources in nature include fluorinerich volcanic rocks, calcareous dolomites, phosphorus-bearing rocks/loess and Quarternary loose sediments. Under special conditions fluorine is concentrated in ground water or soil and seeks its way into human body through diet. Areas With high fluorine concentration responsible for the fluorine disease can be classified into four types, depending on characteristics of geochemical environment: (1) Arid and semiarid calcium-rich soda saline areas; (2) Semiarid, alternatively marine-terrestrial strata with a high degree of salinity; (3) Semihumid iron- and aluminum-rich intermediate-acid soils; (4) Localities where fluorine-rich rocks or deposits are developed;and those with high fluorine content as a result of industrial pollution. Based on medical statistics and chemical analyses, of water, soil, food and other related samplcs,this work will provide a scientific baekground for the prevention and control of fluorine disease. 相似文献
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Lakshmi Narasimharao Kodali Jagadiswararao Ramayanam 《中国地球化学学报》2006,25(B08):65-65
Endemic fluorosis, caused by excess fluoride in water, is widespread in the arid and semiarid tracts of India. This disorder is of recent origin and developed due to certain faulty water management practices. After Eager reported ‘dental mottling' among emigrants from Pozzuli in Italy in 1901, several such reports came from all over the world. From 3 works published independently from Pennsylvania, Arizona and South Africa in 1931, it was known that this disorder is caused by drinking water containing over 1 mg/L fluoride during formation of permanent teeth among children.‘Skeletal fluorosis/Osteofluorosis', affecting bones and joints among adults was reported by Moeller and Gudjonsson in 1932 due to accumulation of fluoride in hard tissues by drinking water with over 7 mg/L fluoride for several years. In course of time fluorosis has been reported in over 22 countries from all over the world. Fluorosis spreads now among 67 million people in the entire arid and semiarid tracts of India. The work of National Institute of Nutrition of India at Hyderabad in 1977 revealed the spread of endemic ‘genu valgum' (knock-knee) crippling lower limbs right from childhood in association with fluorosis in most parts of India. Although preliminary work revealed that genu valgum is caused by drinking waters poor in calcium and rich in molybdenum, efforts these disorders by supplying low-fluoride water should be taken up to know its exact cause to the communities could not so eradicate The governmental efforts to eradicate the problem. 相似文献
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Hairong LI Qinbin LIU Wuyi WANG Xuehui LIU Hailong LI Shuhai LI Xiaoyu ZHAO Lizhen WANG 《中国地球化学学报》2006,25(B08):73-74
Tea bush is one of the plants cultivated in acidic soil, and is a typical hyper-accumulator of F and Al. Brick tea is a kind of brick-formed tea compressed using the older and coarse leaves and branches of tea trees. Brick tea mixed with milk is drunk as a daily indispensable beverage for Mongols, Ewenki, and other minority nationalities in the pastoral and semi-pastoral areas of Northwest China. It is reported that drinking brick tea can result in dental and skeletal fluorosis due to the high F content in it. Because Alzheimer's disease (AD) is related with Al in human brain, and Al has potential toxicities for skeletal and neural systems, 相似文献