Distribution And Origin Of Fluoride In Water And Soil Environment And The Biological Effects In Jilin Qian'an

It is very high incidence rate and large area of prevalence state of drinking water-born endemic fluorosis in our country. They mainly distributed on the country area, pasturing area and mountainous regions far away. At present, the threaten population is over a hundred million. The west of Jilin Province is an area where local fluorosis is very serious, and Qian'an is one country of the worst area in Jilin Province. Various department of our province have investigated on water and fluorosis for many years, but because of omnifarious reasons, the prevention of fluorosis effect is not good enough. It is obvious that the harm of fluorosis is still very severe, prevent drinking-fluorosis is no time to delay.Local endemic fluorosis is a biogeochemical disease. Flouride is one of the most active chemical elements. It almost reacts with all other chemical elements. Therefore, in the most situations, flouride are widely distributed in nature as fluoride. In the area of fluorosis, fluorid content always in a very high level. The distribution of fluorosis area is closely influenced by the special natural environment of the area. In order to solve the problem about fluorosis completely, we did particular investigation of the distribution and orign of fluorosis and the biological effects, therefore find effective measure, thus the fluorosis problem could be solved radically. The application of measures of improvement, adjustment and maintains of regional ecological environment, which would be bringing about a great advance of scocial economy and the coordinated development of economy and ecological environment.Because of the characteristic feature of the natural environment, economic condition and local endemic fluorosis, in the basis on selection of evaluation models, evaluation factor and confirmation on target system, we made the evaluation of drinking water quality and evaluation to soil environment. We select fuzzy overall evaluation in the evaluation of drinking water quality and fluoride individual assessment. The results showed that most quaternary pore phreatic water surpassed the requirement of the state standard. Quaternary pore confined water was polluted by quaternary pore phreatic water, water quality of which was worse. The quality of tertiary system confined water is better, which had good prospects of drinking exploitation. We select method of grey incidence degree in soil environmental quality model selection. There are five quality grade of quality of soil environmental.The results showed that the quality of soil environmental was grade three and four. The quality of soil environmental in the east of Qian'an was better than which is in the west. The soil impoverishment and salinization in Qian'an is very severity.Chemical analysis of underground water showed that the chemical components of quaternary pore phreatic water and quaternary pore confined water were complicated, mineralization degree of which is higher, which were possessing slight alkaline; The chemical components of the tertiary system confined water was simple, which had lower mineralization degree and was distributed. The tertiary system confined water was slight alkaline and lower fluorin and the equality of which was better. The tertiary system confined water meets the potable water criteria.Base on the geographic coordinates of sampling pointshas, the fluoride distribution draw in Qian'an had been established on the support platform of Mapgis,with fluoride isoline diagram of quaternary pore phreatic water in SPSS. The results show that the fluoride of quaternary pore phreatic water is higher, the distributed regular of fluoride is higher in southwest than in northeast in Qian'an. The centre concentration of the fluoride was around Dabusu town, the concentration of the fluoride is higher than 6mg/L. The quaternary pore phreatic water has two sources: original source and secondary source. Original source is the released fluoride by demorphism of mother rock. Secondary source is fluoride created by eluviation and desorption of sedimentary rock and released by carbonate salt. By two action methods above, fluoride transfered in the environment and accumulated in the quaternary pore phreatic water. There are two reasons of the accumulation: soda-salinization and evaporation. The soda-salinization increased alkalescence of water and lower the concentration of Ca2+which increased the concentration of F- in the quaternary pore phreatic water. By occasion of the rare rainfall and wicked environment in this area and intense evaporation, the shallow underground water was concentrated to high concentration of fluoride water. The data of water sample showed that F- was negative correlated with Ca2+, Eh, positive correlated with HCO3-, total hardness, total dissolved solids, pH, total iron.The results of the soil sample showed that the soil in Qian'an was slight alkaline which had lower organic matter, humus constitution and total fluoride. The research of the fluorine formations in soil showed that dissolved fluorine was higher. The reason of that is intense evaporation which concentrated soil solution and highed concentration of fluoride. The content sequence of fluorine formation: Residual F>Fe/Mn oxide bound F>soluble F> organic matter bound F> humus constitution bound F> exchangeable F> organic matter bound F. Correlation scatter diagram among Dissolved Fluorine, Total Fluorine and Property of Soil with SPSS, which showed that total F was significantly positive correlated with CaO, MgO, otal iron, Se, CEC, was positive correlated with organic matter and humus constitution, was negative correlated with pH; Residual F was significantly positive correlated with Total Fluorine, CaO, total iron, CEC, Ca2+, HCO3-, was positive correlated with Se, organic matter and humus constitution, was negative correlated with Cl- and pH. The fluorine formations are inter-changeable. There are four chemical reactions in the environment of soil: precipitation-solution equilibrium, complexation-dissociation equilibrium, adsorption-desorption equilibrium, acid - base reaction.Study on correlation between fluoride content in drinking-water and dental fluorosis and skeletal fluorosis showed that fluoride content in drinking-water had close correlation with the prevalence of dental fluorosis and skeletal fluorosis. Draw spacial graphic overlay between fluoride content in drinking-water and the prevalence of fluorosis with Mapgis software, base on the spacial graphic overlay, which showed that the area that had a higher fluoride content, also had a higher rate of fluorosis, the highest fluoride content area appeared the highest rate of fluorosis. The defluorides of drinking water was the basic measure of prevent drinking-fluorosis. Whole Experience from defluoride of drinking water before, make a suggestion to reasonable control methods of endemic fluorosis control.