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1.
不同茶园茶叶氟含量及土壤氟的形态分布 总被引：7，自引：0，他引：7
通过对我国中西南产茶区12个茶园土壤样品和茶叶样品的采集,探讨了不同茶园茶叶氟含量和茶园土壤氟的形态分布规律。老叶和嫩叶氟含量分别为221～1 504 mg/kg和49.0～602 mg/kg,老叶氟含量是嫩叶的2.5～8.1倍。各形态氟含量随土壤层次加深没有统一变化规律,但各层土壤不同形态氟含量均为残渣态铁锰氧化物态＞有机结合态＞水溶态＞交换态。土壤pH值、有机质含量和阳离子交换量对茶园土壤氟的形态分布有不同程度的影响。老叶和嫩叶氟含量随水溶态氟含量的增加均呈显著增加趋势,但与其他形态氟含量没有显著的相关关系。 相似文献
2.
安溪县光德村地氟病区生态地球化学特征 总被引：5，自引：2，他引：3
在安溪县光德村地氟病区进行生态地球化学调查发现,岩石、土壤、饮用水、水稻、蔬菜中F含量较高,而Cu、Mo、Ca等人体必需的元素严重缺乏;饮用水中F严重超标, F-高达4.18 mg/L,达地下水Ⅲ类标准的4倍之多,且水质pH低于饮用水标准的下限6.5,属酸性水质,不适合饮用,该地区特殊的生态地球化学环境是导致地氟病的主要原因。 相似文献
3.
Groundwater is one of the most important natural resources of drinking water on the earth planet. In rural areas of Yemen, groundwater is the main resource for drinking as well as for domestic purposes. According to the World Health Organization, one of the most important elements that has to be found in drinking water is fluorine (fluoride) but within the range of concentration of 0.5 up to 1.5 mg/l. Otherwise, any concentration of fluoride out of that range may cause serious diseases in human’s body such as fluorosis, kidney chronic disease, and/or nephrotoxicity. Taiz City, the third important and largest city in Yemen, has been suffering from dental fluorosis for a few decades. The main resource for drinking water in this city and adjacent areas is Al-Howban Basin (the study area) from where 33 groundwater samples were collected from 33 stations. These samples were preserved and then chemically analyzed according to the American Public Health Association Standards. The results reflected high levels of fluoride concentrations up to 3.6 mg/l in groundwater of many stations. GIS mapping was used to produce a geospatial distribution map of fluoride concentrations using ArcGIS-inverse distance weighted (IDW) tool. As a result, three zones of risks were identified in the study area: mild risk zone which covers the major part of the study area, moderate risk zone, and zone of no risk (optimum level zone). The last two zones occupy small portions of the study area. Consequently, dental and skeletal fluorosis, kidney, and/or nephrotoxic diseases are highly expected to be detected in the study area. Groundwater treatment measurements and health precautions are strongly recommended to be taken by local authorities in the near future. 相似文献
4.
Fluorine is one of the potential hazardous trace elements in coal. Fluorine may be released into atmosphere mostly during
coal combustion process. When the coal is burning indoors without any controlling methods (chimney), the fluorine will pollute
the room and is absorbed by food fired (dried) over stoves. Now many people have suffered from fluorosis due to coal burning
indoors in Southwest China. In this paper, the concentration, distribution, mode of occurrences and impact factors of fluorine
in Chinese coals are analyzed. The environmental impacts and typical features of fluorosis are studied. It is concluded that
the value of fluorine in Chinese coals ranges from 20 to 300 mg/kg, and with average value of 122 mg/kg from 5,603 coal samples.
It is higher than the average value of the world coals (80 mg/kg). In provincial coalfields of the SW China, the content of
F is highest and many people have been affected due to coal combustion indoors. 相似文献
5.
Binbin Wang Baoshan Zheng Weijuan Lian Lan Yang Ruizhe Huang Jianping Ruan 《中国地球化学学报》2009,28(2):172-175
In this study, the author determined fluorine in drinking water and urine of residents who are divided into four age groups (5, 12, 35-44, 65-74 aged), living in Huangling City, Shaanxi Province and at 6 villages of Qin'an County, Gansu Province, P.R.China. Some residents are living in fluorine exposure areas. A total of 929 residents (463 females and 466 males) involved in the study were selected from 7 tap water systems. Drinking water samples were collected from each area and analyzed using the fluoride ... 相似文献
6.
To study arsenic(As) content and distribution patterns as well as the genesis of different kinds of water, especially the different sources of drinking water in Guanzhong Basin, Shaanxi province, China, 139 water samples were collected at 62 sampling points from wells of different depths, from hot springs, and rivers. The As content of these samples was measured by the intermittent flowhydride generation atomic fluorescence spectrometry method(HG-AFS). The As concentrations in the drinking water in Guanzhong Basin vary greatly(0.00–68.08 μg/L), and the As concentration of groundwater in southern Guanzhong Basin is different from that in the northern Guanzhong Basin. Even within the same location in southern Guanzhong Basin, the As concentrations at different depths vary greatly. As concentration of groundwater from the shallow wells(50 m deep, 0.56–3.87 μg/L) is much lower than from deep wells(110–360 m deep, 19.34–62.91 μg/L), whereas As concentration in water of any depth in northern Guanzhong Basin is 10 μg/L. Southern Guanzhong Basin is a newly discovered high-As groundwater area in China. The high-As groundwater is mainly distributed in areas between the Qinling Mountains and Weihe River; it has only been found at depths ranging from 110 to 360 m in confined aquifers, which store water in the Lishi and Wucheng Loess(Lower and Middle Pleistocene) in the southern Guanzhong Basin. As concentration of hot spring water is 6.47–11.94 μg/L; that of geothermal water between 1000 and 1500 m deep is 43.68–68.08 μg/L. The high-As well water at depths from 110 to 360 m in southern Guanzhong Basin has a very low fluorine(F) value, which is generally 0.10 mg/L. Otherwise, the hot springs of Lintong and Tangyu and the geothermal water in southern Guanzhong Basin have very high F values(8.07–14.96 mg/L). The results indicate that highAs groundwater in depths from 110 to 360 m is unlikely to have a direct relationship with the geothermal water in the same area. As concentration of all reservoirs and rivers(both contaminated and uncontaminated) in the Guanzhong Basin is 10 μg/L. This shows that pollution in the surface water is not the source of the high-As in the southern Guanzhong Basin. The partition boundaries of the high- and low-As groundwater area corresponds to the partition boundaries of the tectonic units in the Guanzhong Basin. This probably indicates that the high-As groundwater areas can be correlated to their geological underpinning and structural framework. In southern Guanzhong Basin, the main sources of drinking water for villages and small towns today are wells between 110–360 m deep. All of their As contents exceed the limit of the Chinese National Standard and the International Standard(10 μg/L) and so local residents should use other sources of clean water that are 50 m deep, instead of deep groundwater(110 to 360 m) for their drinking water supply. 相似文献
7.
N. V. Ramamohana Rao N. Rao K. Surya Prakash Rao R. D. Schuiling 《Environmental Geology》1993,21(1-2):84-89
Geochemical and hydrochemical studies were conducted in Nalgonda District (A.P.), to explore the causes of high fluorine in waters, causing a widespread incidence of fluorosis in the local population. Samples of granitic rocks, soils, stream sediments, and waters were analyzed for F and other salient chemical parameters. Samples from the area of Hyderabad city were analyzed for comparison. The F content of waters in areas with endemic fluorosis ranges from 0.4 to 20 mg/l. The low calcium content of rocks and soils, and the presence of high levels of sodium bicarbonate in soils and waters are important factors favoring high levels of F in waters. 相似文献
8.
Ayman A. Ahmed 《Arabian Journal of Geosciences》2014,7(8):3069-3083
The occurrence of fluoride in ground water is the focus of the public and has attracted the attention of many scientists all over the world due to its importance in public health. Deficiency or increase of fluoride uptake is considered a public health problem due to the narrow permissible limit which should not exceed 1.5 mg/l according to the World Health Organization (WHO). The range of fluoride tolerance and toxicity is narrow. Deviation from the optimal levels therefore results in dental health effects such as caries and fluorosis. Many studies have found fluorosis to be invariably associated with high concentrations of fluoride in drinking water. Fluorosis is a considerable health problem in many areas of the world including Brazil, China, East Africa, Ghana, India, Kenya, Korea, Malawi, Mexico, Pakistan, South Africa, southeastern Korea, Spain, Sri Lanka, Sudan, Taiwan, Tanzania, and Turkey. Fluoride in groundwater of Quaternary aquifer of the Nile Valley, Egypt, does not gain the attention of the authors in the Nile Valley which makes the public health status of fluoride is not certain. The present work aims at investigating the fluoride concentration of Quaternary groundwater aquifer at Luxor as a representative area of the Nile Valley to be a base line for subsequent studies and criteria for public health. Ground water samples were collected from Quaternary groundwater aquifer at Luxor area, Egypt and analyzed for the purpose of investigating fluoride content. The results showed that fluoride concentration in the study area ranges between 0.113 and 0.452 with an average of 0.242 mg/l. Sources of fluoride in the study area can result from the natural dissolution from fluoride-rich minerals, fertilizers and from groundwater recharge. It is worth mentioning that low fluoride content in the study area is considered a public health threat specially limited growth, fertility, and dental caries. Corrective measures should be taken to avoid the public health impacts of fluoride deficiency at Luxor area as well as similar areas in the Nile Valley. A public health program should be initiated to account for the deficiency of fluoride in groundwater and deal with the other supplementary fluoride sources in food or fluoridation of drinking water supplies. 相似文献
9.
Appraisal of highly fluoride zones in groundwater of Kurmapalli watershed,Nalgonda district,Andhra Pradesh (India) 总被引：2，自引：0，他引：2
N. C. Mondal R. K. Prasad V. K. Saxena Y. Singh V. S. Singh 《Environmental Earth Sciences》2009,59(1):63-73
Fluoride (F) contamination study had been carried out to see its allocation in Kurmapalli watershed, Nalgonda district, Andhra
Pradesh, India. The study area is located about 60 km SE of Hyderabad city. The groundwater is the main source of water for
their living. The groundwater in villages and its surrounding are affected by fluoride contamination and consequently the
majority of the people living in these villages has health hazards and is facing fluorosis. The purpose of this study is to
identify the wells with high F, raise awareness in people, study the water chemistry, and also find out the source of F in
groundwater. A total of 32 groundwater samples were collected from different wells in both shallow aquifers and deeper fractures
zones during October 2004. The chemical analysis of groundwater has been done. Fluoride values vary from 0.7 to 19.0 mg/l.
It is noted that the maximum value (19.0 mg/l) is one of the highest values found in groundwater in India and 78% of the total
samples show F concentrations that exceeds the permissible limit value (1.5 mg/l). The highest value of F is found at Madanapur
bore well which is located at central part of the watershed. The F value of this bore well was monitored from October 2004
to October 2006. During this period the F concentration varies from 17.8 to 21.0 mg/l with mean 19.3 mg/l. There is no correlation
of F with chemical parameters except calcium. The Ca has shown inverse proportional with F. Water–rock interaction studies
were also carried out to understand the behavior of F in groundwater at prominent F affected areas. Rock samples were collected
and analyzed, and found their enrichment of F. The anthropogenic possibility of F is almost negligible. The rocks of this
area are enriched in F from 460 to 1,706 mg/kg. It is indicated that the rock–water interaction is the main source of F in
groundwater. The highest values of F are found in middle part of the region and are related to the occurrence of fluoride
rich rocks and their chemical kinetic behavior with groundwater. 相似文献
10.
Obaid Aziz Alharbi Oumar Allafouza Loni Faisal K. Zaidi 《Arabian Journal of Geosciences》2017,10(2):35
The present study was carried out in the Mulaylih area which forms a part of Wadi Al Hamad in the Madinah Province of Saudi Arabia. Thirty groundwater samples from agricultural farms were collected and analyzed for various physio-chemical parameters including trace elements. The area is occupied by the Quaternary alluvium deposits which form shallow unconfined aquifers. Evaporation and ion exchange are the major processes which control the major ion chemistry of the area. The extreme aridity has results in high total dissolved solid values (average of 9793.47 mg/l). Trace element concentrations are low and are mainly attributed to geogenic sources (silicate weathering). Na-Cl groundwater type is the main hydrochemical facies found in the area. The waters are found to be oversaturated with calcite/aragonite and dolomite. The average nitrate concentration was found to be 134.10 mg/l and is much higher than the WHO recommended limit of 50 mg/l in drinking water. Their high values are mainly associated with the application of N-fertilizers on the agricultural farms. The average fluoride concentration in the study was found to be 1.54 mg/l. The relation between F and Cl and Cl and Na reveals that the fluoride concentrations are mainly attributed to geogenic sources. A comparison of the groundwater quality with the Saudi drinking water standards shows that the water is unfit for drinking. The high salinity and sodicity of the groundwater make it unfit for irrigation. Principal component analysis resulted in extraction of four principal components accounting for 79.5% of the total data variability and supports the fact that the natural hydrochemical processes (evaporation and ion exchange) control the overall groundwater chemistry. 相似文献
11.
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
12.
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
13.
各类型氟中毒病区与各类地质环境存在着明显的一致性。中、重病区类型区分布于地下水迳流的区域汇水区 冲积湖积低平原 水化学作用的元素富集区。单一中病类型区分布在迳流区——汇水区的过渡带 风砂覆盖的冲积湖积平原和冲积湖积平原的结合部 水化学作用方向的砂丘水对致病水层的补给淡水。单一轻病类型区分布在地下水的迳流区 风砂覆盖的冲积湖积平原 水化学作用方向的元素迁移区。镶嵌于中、重病类型区内的轻病区分布在冲积平原(霍林河河漫滩) 水化学作用方向为河水的对致病水层补给淡化。饮水氟含量与氟骨症患病率呈定域正相关关系,当饮水氟含量超过6 mg/l时,患病率保持基本不变。影响氟中毒滋生的诸地质环境因素中地下水动力条件起着根本性作用。 相似文献
14.
Selenium source in the selenosis area of the Daba region,South Qinling Mountain,China 总被引：11，自引：0，他引：11
Naore Village in the Shuang'an countryside, Ziyang County, Shaanxi Province is located in the Daba region of South Qinling Mountain. It is one of two selenosis or selenium poisoning areas in China. Crops grown in the area are enriched in selenium. The soil is derived from high-selenium, pyritic, black carbonaceous slate and volcanic tuff of the Lujiaping Formation, Early Cambrian and Late Neoproterozoic in age, which is exposed in this area. The Lujiaping Formation is more than 40-m thick. Selenium content of the volcanic tuff averages 32 mg/kg Se and the black carbonaceous slate averages 22 mg/kg Se, which represent the highest concentrations recorded among all the strata and rocks sampled in the Daba region of South Qinling Mountain. This series of selenium-enriched rocks is also found in other places in the Daba region, South Qinling Mountain, where the soil contains about 10 to 30 mg/kg Se. These zones are latent selenosis zones in the Daba region. In addition, a selenium-enriched black carbonaceous shale, of Early Cambrian age, and containing 10 to 40 mg/kg Se, occurs in several other provinces in the south of China. 相似文献
15.
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17.
The spatial distributions of Cd, Co, Cr, Cu, Hg, Mn, Ni, Pb, and Zn concentrations in surface soils of Guangdong Province, China, were investigated to evaluate the environmental quality of these potentially toxic elements using 261 samples. The following average concentrations were obtained: Cu, 17.4 mg/kg; Ni, 17.7 mg/kg; Cr, 56.7 mg/kg; Co, 6.8 mg/kg; Mn, 223.2 mg/kg; Pb, 36.6 mg/kg; Hg, 0.10 mg/kg; Cd, 0.09 mg/kg; Zn, 49.8 mg/kg. Correlation analysis was applied to the data matrix to evaluate the results and identify the possible sources of metals. Distribution maps of the elements were created using the inverse distance weighted interpolation method. The nine metals exhibited generally distinct geographical patterns. Results showed that 5,173 km2 of the study area presented higher pollution indices and was slightly polluted. 相似文献
18.
滇黔“燃煤污染型”氟中毒重症区粮食氟和砷污染的主要途径 总被引：3，自引：0，他引：3
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.
Mineralogical and geochemical studies were undertaken in the volcanic area of Biancavilla (Catania, Italy) with the aim of
explaining the nature of the high As and F contents of the area’s rocks. As and F contents in soils and groundwater were also
investigated. The metasomatised benmoreite lavas show fluorine and arsenic concentrations up to about 3,000 and 1,000 mg/kg,
respectively. Mineralogical analyses show that fluorine occurs mostly in fluoro-edenite and apatite-(CaF) crystals, both abundantly
present in the altered rocks, while As is exclusively attributed to the apatite-(CaF) crystals. Specifically, arsenic was
observed only at the borders of these apatite crystals. Leaching tests and sequential extraction procedures were carried out
to evaluate the potential remobilisation of As and F by the mineral phases and the eventual risks induced by their spreading.
The results of the leaching tests suggest that As is almost totally associated with the ‘easily reducible’ fraction and that
it is released by the preferential dissolution of the arsenic enriched rims of apatite-(CaF) crystals. In soils, As concentration
is relatively low (about 15 mg/kg, on average), while F ranges from 236 to 683 mg/kg. The underground waters supplying the
town of Biancavilla show As and F contents lower than the allowed limits for drinking water, (As:10 μg/L, F:1–1.5 mg/L). The
limited distribution of these rocks and the relatively limited mobilisation by the minerals both contribute to maintain low
As and F values, in soils and groundwaters, despite the high values in metasomatised lava samples. 相似文献
20.
Amar Messaïtfa 《Environmental Geology》2008,55(2):377-383
In the Algeria South, the dental fluorosis is a “silent” epidemic spreading within the populations. The present study was
aimed to determine the fluoride content in water, dates and tea that are widely consumed. The results reveal that 35% of water
wells had excessive fluoride levels (>1.5 mg/L). The eastern areas where dental decay is the most widespread pathology present
the highest contents. Dates, tea and water are considerable sources of fluoride, with a daily contribution of 10, 20 and up
to 70%, respectively. For these three sources, the daily intake of fluoride ingested by an adult exceeds the proposed safe
threshold of 0.05–0.07 mg/kg day. 相似文献