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1.
Brick-tea-type fluorosis is a peculiar endemic disease in China, which had been discovered in minority areas of western China since 1980, and distributed mainly in Tibet, Inner Mongolia, Gansu, Xinjiang, Qinghai and parts of Sichuan Province. The prevalence rate of fluorosis in Tibetan and Mongolian nationality people was higher. Epidemiological investigation showed that fluorosis morbidity and degrees were different in different brick-tea drinking areas, and it was probably caused by drinking various kinds of brick tea from different regions. Therefore, we collected 33 samples of brick tea from six provinces where minority nationalities were accustomed to drinking a large quantity of brick tea. F concentrations were determined by the combustion hydrolysis-ion selective electrode method. The results showed that among the brick teas, the F concentrations ranged from the minimum 74.1 mg/kg in Yunnan Province to the maximum 991.2 mg/kg in Sichuan Province. Besides, there was a great difference among the various kinds of brick tea, and F concentrations decreased in the order of Kang brick tea, Green brick tea, Black brick tea, Mi brick tea, Fu brick tea, Chitsu ping tea, Puerh tea, and Tuo tea. The average F concentration in brick teas was 431.92 mg/kg.  相似文献   

2.
Drinking water-type fluorosis is the most harmful endemic disease in China with the largest number of sufferers. Although the implementation of the policy to alter water sources to lower fluoride level has effectively controlled the spread of this kind of endemic disease, its prevalence could not thoroughly be stopped because the high-fluoride environmental background in these endemically diseased areas could still do harm to human health through food chain. Therefore, it is necessary to conduct a more deep-going study on the drinking water-type fluorosis. To investigate the effect of high fluorine environmental background on crops and human health in the hot spring-type fluorosis-diseased areas, local water, paddy soil, rice, whole vegetables and soils around their roots were sampled for analysis. The results were compared with those of the control groups in fluorosis-free areas which are similar to the fluorosis-diseased areas both in natural background and in social background. It is indicated that rice and vegetables can accumulate water-soluble fluorine either in soils or in irrigating water, and different crops have different abilities of fixing fluorine. The contents of fluorine in different parts of vegetables in the fluorosis-diseased and fluorosis-free areas were statistically categorized. The results showed that the fluorine contents of roots, tubers, leaves and flowers of vegetables in the fluorosis-diseased areas are 3.56, 1.17, 3.07 and 3.23 mg/kg, respectively. However, comparisons showed that in the fluorosis-free areas, the fluorine contents are 2.17, 0.70, 1.91 and 2.52 mg/kg, respectively. Moreover, different parts of a crop also show significantly different fluorine fixation abilities. It is demonstrated that the fluorine contents of the strongly metabolic parts are relatively high. For example, the fluofine contents of roots, leaves and flowers of vegetables are much higher than those of stems. The fluorine fixation ability of seeds is very weak. In order to reduce the risk of human body's  相似文献   

3.
徐州地氟病区植物中氟的分布及其环境意义   总被引:12,自引:0,他引:12  
徐州地氟病区几种主要粮食中氟的含量变化在0.70-0.85mg/kg之间,均不超过国家卫生标准值。各种主食蔬菜中氟的含量变化在1.88-12.25mg/kg之间,远超过国家卫生标准,其中以青菜氟含量较高(12.25mg/kg),同种蔬菜叶中氟含量高于块茎和果实的氟含量。不同树中氟含量高达24.56-34.29mg/kg。相关分析表明,植物中的氟含量主要取决于土壤中水溶性氟的含量。叶菜(青菜、白菜等)和树叶中氟含量远远超过土壤中水溶性氟的含量(病区土壤中水溶性氟含量平均值9.60mg/kg),说明氟有随水向植物叶子中富集的趋势。徐州地氟病区主食粮食对人体健康不构成伤害,主食蔬菜氟含量高,长期食用是引发地氟病的重要因素之一。  相似文献   

4.
浅层地下水系统氟地球化学行为的数值模拟   总被引:2,自引:0,他引:2       下载免费PDF全文
曾溅辉 《地质学报》1995,69(3):267-276
本文以重要的命必需元素氟为研究对象,选择地方性氟病比较严重,浅层高氟地下水形成分布在我国北方地区具有代表性的河北邢台山前平原为典型研究区,在大量野外工作和模拟实验研究基础上,应用国外近十几年发展起来的地下水地球化学定量研究方法-地下水地球化学模拟,以及多反应组分系统水动力弥散运移与化学反应耦合模型的理论和方法,对浅层地下水系统氟的地球化学行为进行数值模拟,定量研究了大气降水入渗条件,水-非饮和带非  相似文献   

5.
The dental and skeletal fluorosis is highly prevalent in Zhijin, Guizhou, especially at Hualuo Village, Hehua Village and Majiazhuang Village. The contents of fluorine in coal, clay used for coal combustion, mixed fuel of coal and clay, corn, and chili from households of the three villages were determined by the pyrohydrolysis-fluorine ion-selective electrode method. The average contents of fluorine in the above samples respectively are 237 mg/g, 2262 mg/g, 828 mg/g, 1419 mg/g, and 110 mg/g. The clay used for coal combustions is the main fluorine source of endemic fluorosis and the inferior coal and weathered coal are the secondary source of fluorine. During the combustion of mixed fuel of coal and clay, about eighty percent of fluorine was volatilized, approximately two thirds of which was from the clay and the other one third from the coal. The occurrence of fluorine in clay used for coal combustion is closely related to apatite and hornblende. The contents of fluorine in corn and chili, dried by coal-clay mixed fuel are about 1400 and 73 times higher than the permitted level of fluorine in foods according to the Chinese Standard. It is worth paying attention to the high-fluorine indoor surroundings, such as coal, clay, corn, and chili, particularly ash from boiler bottom with the fluorine content of 15738 μg/g. Besides the technologies of fluorine fixation during the combustion,  相似文献   

6.
石墨尾矿烧结砖制备工艺及性能研究   总被引:2,自引:0,他引:2  
山东青岛南墅地区是我国优质石墨的生产基地。石墨资源的开发,对当地经济发展产生了明显的带动和促进作用。但是,石墨选矿厂排放的大量固体尾矿,不仅占用了宝贵的农田,也对区域生态环境产生了不利影响。石墨选矿厂投产以来排放的尾矿,已占用了数十公顷的土地,其中最大的一个尾矿堆场,面积达10公顷,体积约32万m3。裸露于地表的泥沙状尾矿粉末,随风飘扬,极易形成扬沙天气;在多雨季节,大量降水又形成泥沙流,危及周围农田。为解决尾矿带来的环境问题,石墨矿及当地政府每年都要花费巨资和人力对尾矿进行掩盖,但治理效果不佳…  相似文献   

7.
贵州西部氟中毒地区氟来源地质背景研究   总被引:1,自引:0,他引:1       下载免费PDF全文
贵州省西部广泛分布上二叠统煤系地层,燃煤型氟中毒严重影响当地居民的身体健康。引起氟中毒的氟是多来源的,影响氟中毒的因素是多方面的。高氟含量的岩石粘土岩、煤、页岩等是氟的初始来源体;高氟含量土壤是氟第二个层次的来源;高氟含量土壤中种植的农作物是第三个层次的来源;燃煤烟尘直接排放室内空气中和用燃煤烘烤食物等,使空气、食物和水中氟含量增高,是一重要的人为氟来源。人通过呼吸高氟含量的空气和食(饮)用高氟含量的食物(水)将氟沉淀在体内,造成氟中毒。  相似文献   

8.
The Xingtai piedmont plain in Hebei Province is a representative area in northern China where endemic fluorosis is serious and shallow high-F ground water is distributed. In this paper, the area is selected as a typical study area, and on the basis of large amounts of field work and the experiments, through groundwater geochemical modelling and by applying the theory and method of the coupled model of hydrodynamic transport and chemical reactions in a multicomponent system, the author performed numerical modelling of the geochemical behaviour of fluoride in a shallow groundwater system, quantitatively studied the hydrodynamic transport and chemical reaction of fluorine migration, transformation and concentration in a water-heterogeneous unsaturated soil system under the conditions of meteoric water infiltration and quantitatively determined the speciation of fluorine and the saturation state and dissolution/precipitation trend of various solid precipitates in shallow high-F groundwater, thus deepening t  相似文献   

9.
利用湖泊底泥和粉煤灰制备瓷质砖的实验研究   总被引:6,自引:0,他引:6  
将湖泊底泥引入瓷质砖的生产, 既可消除污染, 又能减少传统的瓷质砖生产中所需的粘土.以武汉市东湖底泥和湖北黄石电厂粉煤灰为主要原料, 辅以伟晶花岗岩、石英为添加剂, 设计4个底泥含量分别为4 0 %、5 0 %、6 0 %和70 %的配方, 每一配方压制6片生坯, 分别在1 190, 1 175, 1 160, 1 130, 1 115和1 100℃下烧成.XRD分析显示瓷坯中的莫来石晶相随烧成温度的升高而增加.在1 160~1 175℃烧成的瓷坯的吸水率和断裂模数测试结果分别为0.0 8%~ 0.2 0 %和39.36~ 51.0 8MPa, 表明利用湖泊底泥和粉煤灰作为主要原料可以烧制瓷质砖, 二者的总用量可达75 %~ 80 %.   相似文献   

10.
贵州地方病氟中毒的氟源、致病途径与预防措施   总被引:6,自引:0,他引:6  
运用高温燃烧水解-氟离子选择性电极方法,对贵州织金县地方病氟中毒重灾区的化落村、荷花村和马家庄村居民用的粉煤、拌煤黏土、煤泥混合燃料、玉米、辣椒等系列样品进行了氟含量测定,结果表明,这些样品中的氟含量均值分别为237.1/μg/g、2261.9/μg/g、827.9/μg/g、1418.8/μg/g和110.1/μg/g。玉米和辣椒中氟的含量超出国家标准食品中氟允许量的约1000倍和100倍。氟中毒的氟源主要来自拌煤黏土,氟在拌煤黏土中除了以磷灰石、角闪石形式存在外,与伊蒙混层矿物和伊利石的吸附密切相关。煤泥混合燃料在燃烧过程中,约有80%的氟被释放。除了采用固(降)氟技术以外,病区居民改变生活习惯,在食用辣椒前用清水淘洗,把玉米粒加工成玉米面前进行脱皮处理,可以除去食物表面相当一部分氟,对预防地方病氟中毒有重要作用。  相似文献   

11.
刘家仁  王尚彦 《贵州地质》2005,22(3):192-195
地方性氟中毒病简称“地氟病”,是一种严重危害人体健康的地方病,是因人体过量摄入氟元素所致.燃煤污染型地氟病,是燃烧煤炭时氟元素挥发污染空气和被烘烤的粮食、辣椒等食品,人体通过呼吸被污染的空气和食用被污染的食品而引起的氟中毒病.笔者通过对典型重病区织金县荷花村调查,获得如下认识:高氟煤炭和高氟粘土(岩)同为燃煤污染型地氟病的氟源,上二叠统龙潭组下部地层应为其重要产出层位;查明高氟煤炭和高氟粘土(岩)的成因、分布状况和分布规律,为政府制订科学合理、切实可行的防治措施提供科学依据很有必要.  相似文献   

12.
福建铁观音茶园生态地球化学特征   总被引:2,自引:2,他引:2       下载免费PDF全文
东南沿海是铅等重金属的地球化学高背景区。该地区广泛分布酸性红壤,酸雨沉降、不适当施肥导致土壤酸化以及由此引发土壤重金属生态风险令人关注。以福建省铁观音主产区为研究区,采集了79个茶园的表层和亚表层土壤样、茶叶样品,测定了重金属元素以及土壤常量元素和理化指标。研究表明,福建铁观音茶园土壤中Hg、Pb、Se、Zn高含量主要由地质背景所引起,土壤常量组分、有机质、酸碱度等理化条件对土壤元素含量有一定的影响;铁观音茶树老叶中As、Cd、Cr、Hg、Se、Pb、F等非植物营养元素含量明显高于嫩叶,显示这些元素随植物生长逐渐累积的特征,而嫩叶中植物生长必需的营养元素Cu、(Ni)、Zn则高于老叶,反映出微量营养元素在茶叶生长部位相对富集的特征;多数情况下土壤与茶叶间元素含量相关性差,说明茶树对土壤元素的吸收累积受到多种复杂因素的影响。研究表明茶叶与土壤Pb、Cr具有显著正相关性,为建立铅污染土壤生态效应预测评价模型提供了基础依据。  相似文献   

13.
Four experiments have been done on the influence of times of infusion, temperature, time and ratio of tea to water on the dissolving characteristics of fluoride and aluminum in brick tea. According to the results, the behaviors of F and Al which found their way into tea liquor were analyzed and the conclusions have been drawn: the dissolution of F and Al is not synchronous and after the elements find their way into tea liquor respectively, they will be reset to form complexes of F and Al.  相似文献   

14.
对浙江省农业地质环境调查有关农产品安全性资料成果,分析在茶、稻中的铅、氟含量水平及安全性,并探讨了影响农产品安全的原因,进行了茶叶和水稻中铅、氟限量标准的讨论,认为国内对食品卫生标准制定趋于偏紧。参照日本、加拿大的茶叶氟元素限量标准,提出浙江省茶、稻的铅、氟元素限量标准。  相似文献   

15.
李端生 《吉林地质》2001,20(2):72-79
该文笔者多年研究大骨节病原始原因的一项新说。即病区外环境低氟。引起体内以低氟为中心的代谢紊乱,从而导致以骨骼系统为主的病变-大骨节病。防治该病,应向体外补氟。药疗这一进补方式故然必然,但最有效又生活化的办法是食疗。食疗又分氟盐防治和饮茶防治两种。而最适用且简便的方法是提倡患区人群适度饮茶,并且应从儿时做起。关于补氟和饮茶等防治大骨节病的实践,笔者已浓缩于下面四则拾趣之中……。  相似文献   

16.
David Grigg 《GeoJournal》2002,57(4):283-294
Coffee and tea are both drunk in most countries, but typically one predominates. Coffee is the preferred drink in Europe and the Americas, tea elsewhere. Until the early eighteenth century coffee production and consumption was confined to the Islamic world, tea production to East Asia. European traders altered this pattern dramatically. The present pattern of coffee consumption is influenced by income per capita, that of tea is not. Religious influences played some part in the early development of both tea and coffee but have little relevance at the present. National factors have influenced wider patterns. British preference for tea was taken to all their colonies. In recent years fears about health have had some influence on coffee consumption. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

17.
苏南局部富硒土壤及其天然富硒茶叶初步研究   总被引:5,自引:2,他引:5       下载免费PDF全文
硒(Se)是对人体健康有重要影响的微量元素,不同地区土壤中硒含量分布是不均匀的,依据局部富硒土壤线索开发天然富硒食品是农业地质环境研究的一个重要方向。江苏省1∶25万区域土壤地球化学调查资料显示,尽管全省表层土壤总体相对贫硒,但在江苏南部溧阳—宜兴一带局部低山丘陵地区存在较大面积的富硒土壤,并据此线索在当地新发现了天然富硒茶叶。初步研究表明当地富硒土壤的形成与特定地质背景有关,生产天然富硒茶叶的土壤环境相对优越。  相似文献   

18.
滇黔地区室内燃煤污染所致慢性氟中毒是我国特有的长期困扰我国的主要环境健康问题之一。为了探讨滇黔"燃煤污染型"氟中毒重症区粮食氟和砷含量及污染的主要途径和改灶降氟炉的使用状况及氟中毒防治效果等,从2005年至2008年11月,连续在云南省和贵州省氟中毒较严重的地区——昭通市的镇雄、威信、大关、彝良、昭阳区以及贵州威宁石门坎、毕节、郝章和非病区昭通巧家、鲁甸县等地,调查了当地500余户改灶降氟炉的使用状况、生活习惯及粮食干燥和保存方式、儿童氟斑牙患病率等,系统采集和分析测定了改灶降氟炉使用区和非使用区烘烤前后粮食的氟和砷等含量。结果发现:无论重病区或非病区,未烘烤粮食的新鲜玉米的氟含量均低于4μg/g,一般为1~2μg/g,砷含量低于0.1μg/g,一般在0.01~0.05μg/g之间;而敞炉快速烘烤(10~15天)的玉米氟含量比烘烤前增加4~200倍,一般在10倍以上,含量在10~20μg/g之间;辣椒氟含量比烘烤前增加了30~100倍,最高达1274.39μg/g;烘烤辣椒的含氟量一般高于玉米的氟含量,均高于20μg/g;砷的含量也10~40倍地增加,增加幅度与氟相当。被调查的500余户烘烤粮食的居民中,无论改灶降氟炉使用户或非使用户,只要是需要烘烤粮食的用户,没有一户是单独使用改灶降氟炉烘烤粮食,全部用2~3个以上的敞炉烘烤粮食,其烘烤后的粮食的氟和砷污染程度相当。结论:滇黔"燃煤污染型"氟中毒区重症区大多数新鲜玉米和辣椒的氟和砷的含量低于或稍高于国家标准;无论烘烤粮食的煤及拌煤黏土中氟和砷含量的高低,烘烤后的玉米和辣椒的氟含量全部超标,砷含量增加十倍以上,敞炉快速烘烤粮食是滇黔氟中毒重症区的粮食氟和砷污染的主要路径和主要成因。改灶降氟炉的推广,不能降低滇黔"燃煤污染型"氟中毒区粮食的氟污染、根治燃煤污染型氟中毒症发生的主要原因,是当地潮湿多雨,气候阴冷,而改灶降氟炉的火力太小,无法在短期内快速烘烤干粮食,所以,无论改灶降氟炉使用区或非使用区,全部用敞炉烘烤粮食。因而在阴冷潮湿的滇黔山区,仅仅推广火力较小的改灶降氟炉,无法隔断烘烤粮食时的氟污染源,对防治滇黔"燃煤污染型"氟中毒是远远不够的。  相似文献   

19.
酒钢1#高炉于1990年3月12日在生产过程中突然发生坍塌,造成国内外冶金史上罕见的高炉生产特大事故。坍塌后对炉缸、炉底风口下沿粘土残砖、炉缸中部环碳砖、炉底高铝砖缝中渗结物等进行了分析,初步查明上述炉料中含有较多的碱金属氧化物K2O、Na2O及锌等有害元素是造成炉缸内粘土砖破损和碳砖产生环形裂缝的主要原因。1 物相组成1-1 化学成分分别从炉缸、炉底采取试样进行化学分析,结果列于表1。表1 试样化学成分(%)Table1 Chemicalcompositionofsamples(%)样品号Si…  相似文献   

20.
活性氧化铝除氟性能的试验研究   总被引:1,自引:0,他引:1  
通过静态试验,研究了活性氧化铝对F-的吸附性能,分析了原水氟离子浓度、pH值、活性氧化铝的投加量和吸附时间对吸附性能的影响。研究结果表明:在原水浓度0~50mg/L范围内,活性氧化铝吸附量与原水浓度基本成线性增加的关系;活性氧化铝除氟的最佳pH值为5~7,最佳投加量为10g/L。测定了在25℃时活性氧化铝除氟的吸附等温线,并对吸附等温线进行拟合,证明其符合Langmuir吸附等温式。  相似文献   

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