Abstract:Abstract：As the main endemic disease entities prevalent in China, endemic arsenism, fluorosis and Kaschin-Beck disease pose serious threat to people’s health. The distribution and formation mechanism of high arsenic water and high fluorine water in main basin of North China, the characteristics of geological environment in Kaschin-Beck disease area and the research progress of the relationship between each other are summarized in this paper. Then, the research direction is indicated.

Abstract:Abstract：Kaschin-Beck disease (KBD) is an endemic disease with many influencing factors. There are lots of hypotheses on KBD, but its etiology remains unclear. This paper elucidates the characteristics of regional distribution and dynamic changes of KBD in China, discusses the natural and geological environment characteristics and etiology research status. Based on a review on the hypotheses of the KBD etiology, the authors consider that KBD results from the compound effect of multiple factors. Selenium deficiency is the environmental background factor, toxin related to human body in the environment is the main controlling factor, and the disproportion of major and trace elements is an influencing factor. It is suggested that in the etiology research we should attach much importance to the macro and micro analysis combination and the multi-science combination, especially to the medicine and geoscience combination.

Abstract:Abstract：Kaschin-Beck disease is a local endemic osteoarthritis disease. In the past 160 years, experts both in China and abroad have conducted much research work in this aspect and put forward hundreds of hypotheses on the cause of this disease; nevertheless, no final conclusion has been reached. Zoige County is one of the areas in China where the incidence of Kaschin-Beck disease is relatively high. Based on field investigation, geotechnical water sample test and some other researcher work conducted in the disease area, this paper has summarized the distribution of Kaschin-Beck disease as well as local natural environment and geological characteristics and discussed the distribution of Kaschin-Beck disease in relation to local lithology, soil, topography, geological environment, drinking water and some other factors. Some conclusions have been reached: bedrock lithology and soil parent material composition seem to be the basic factors responsible for the distribution of this disease; Se, Mo and Ba are lower in the disease area than in the non-disease area, whereas N, P, Pb and S are higher in the disease area; the disease area and the non-disease area do not show remarkable differences in degree of mineralization, hardness and humic acid content of the surface drinking water; Ce content is lower in the disease area than in the non-grave and non-disease areas. The factors causing the Kaschin-Beck disease are very complex, related not only to geological-geochemical environmental factors of rock, soil and water but also to food structure. The cause of this disease deserves further investigation.

Abstract:Abstract：The pathological mechanism of Kaschin-Beck disease is complex, and the cause of this disease remains a problem of much controversy, in spite of the fact that most scholars believe that there exists some relationship between the Kaschin-Beck disease and the drinking water in the disease area. From the aspects of major components, trace elements and organic matters, this paper have summarized the chemical composition of water in Kaschin-Beck disease areas on the basis of the researches on the Kaschin-Beck disease in the past two decades. It is concluded that many achievements on the study of Kaschin-Beck disease have been gained, but there still exist lots of different views and arguments which deserve further discussion.

Abstract:Abstract：The Kaschin-beck disease is an epidemic disease widespread in such environments as middle-low mountains, low-lying lands (low plain and intermountain valley basin), migration and enrichment areas of elements, and intermediate-acid reducing and alkaline-oxidizing conditions. The non-disease area lies in the transitional zone from the depletion to the enrichment of elements in a neutral oxidization-reduction environment. The Kaschin-Beck disease is a disease affected by various geological environmental factors, in which hydrogeochemistry is the most important factor.

Abstract:Abstract：Kaschin-Beck disease is a kind of endemic osteoarthritis disease, and Zamgtang County is one of the serious areas of Kaschin-Beck disease. An investigation and analysis of water source and water quality of Zamgtang County have led the authors to believe that the low degree of mineralization and high humic acid in drinking water are two key environmental pathogenic factors for Kaschin-Beck disease in that area. Low degree of mineralization results in the lack of nutrient elements necessary for cartilage tissue, and high humic acid damages cartilage cell. In view of this, water improvement demonstration projects exploiting the small-scale deep groundwater have been put into practice. These projects are suitable for the Kaschin-Beck disease area and will cut off pathogenic factors.

Abstract:Abstract：In the study of the factors responsible for Kaschin-Beck disease in northwest Sichuan plateau and the hydorgeochemical conditions of this area, the authors conducted neutron activation tests on the samples collected from different types of water sources in the Kaschin-Beck disease area. The results show that the enrichment of trace elements is obvious in this area, and that high element content is coincident with higher illness whereas low element content is consistent with lower illness. Relative to things of other Kaschin-Beck disease areas, selenium in this area is especially abundant; nevertheless, low selenium content is in accord with higher illness, which conforms to the KBD general laws. A comparative study of different types of sources reveals that the content of total trace elements decreases in order of brook water＞well water＞deep well water＞marsh water＞spring water.

Abstract:提要：在本文中，5种类型的氟的水文地球化学异常被确定，它们的形成过程、在水环境中的流入物源以及浓度水平各异。对它们的特征也进行了讨论。

Abstract:Abstract：Since Mesozoic-Cenozoic, great thickness of Tertiary and Quaternary sediments has been deposited in Songnen fault basin, which has constituted the foundation of water storage structure for the phreatic and confined water. There exists high fluoride in the phreatic and Quaternary confined water, with the fluoride in 194 samples ranging from 0.25 to 14 mg/L (3.45mg/L on average). Large-scale prevalence of fluorosis has resulted from the drinking of high fluoride water. The researches conducted by the authors show that high fluoride groundwater is mainly distributed in the piedmont area, the evaporation discharge zone and the transitional zone in the middle of Songnen basin, where evaporation is strong. In this area, the groundwater hydrochemistry is of HCO3-Na · Mg and HCO3-Cl · Na types, and the total dissolved solid is about 689.84-2005.6 mg/L. The formation of high fluoride water is related to climate, hydrology, geological structure, rock and soil, geological and hydrological conditions of water chemistry and other natural factors, and is also affected by human activity factors such as the irrational exploitation of groundwater. The research on the groundwater environmental characteristics and causes of high fluoride is very important for the effective implementation of safe water supply.

Abstract:Abstract：Fluoride poisoning by drinking high-fluoride water is a rather common phenomenon in the world, and groundwater with high fluoride is very widespread in northern China. As regional groundwater is the main source of water supply, fluoride poisoning has developed to such an extent that it has seriously affected human health. The enrichment of fluoride in the groundwater is a very complicated hydrogeochemical reaction. Results of the studies conducted in northern China are summarized in this paper. It is indicated that regional high fluoride-bearing groundwater on the whole exhibits some characteristics in distribution. The formation of high fluoride water was studied in relation to climate, hydrology, geological structure, rock and soil, geological and hydrological conditions of water chemistry and other natural factors. The groundwater exploration direction and some key points in the high-fluoride groundwater zone are pointed out on the basis of relevant results. Having analyzed the distribution and environmental characteristics of high fluoride-bearing groundwater, this paper advances many effective measures to reduce the fluoride content in drinking water and to cure the disease.

Abstract:Abstract：Exemplified by the result of endemic and eco-geochemical investigation in several cities of the lower Yellow River basin within Shandong Province, the authors studied the relationship between endemic fluoride disease and geological environment. It is shown that endemic fluoride disease has close relationship with soil and potable water. Based on a review of the past work on the prevention and treatment of local endemic fluoride disease as well as the existent problems, this paper suggests that the investigation and study of specialized endemic geological work should be carried out as soon as possible.

Abstract:Abstract：Fluorosis occurs rather widely in Huaihe River basin, and in some local areas, the incidence of fluorosis disease is serous, which is gravely harmful to people’s health and the development of local economy. In the past decades, some scientists and research institutes have done some work for the fluorosis, and for many years China Geological Survey has implemented some projects on environmental geological research including the study of fluorosis in Huaihe River basin. Based on the previous work, this paper expounds the distribution of endemic fluorosis in Huaihe River basin and the fluoride content in groundwater of different depths, and points out four factors responsible for fluoride concentration and two factors causing fluorosis disease. Some water supply measures for prevention and cure of fluorosis disease are also discussed in this paper.

Abstract:Abstract：A suitable process to modify natural clinoptilolite from Beipiao area of Liaoning Province was determined by using contrast experiments of three different modifying methods. The process includes: (1) roasting the zeolite at 700℃ for 5 hours in muffle furnace, (2) soaking it in hydrochloric acid of 10% concentration for 12 hours, (3) using clear-water to wash it to neutrality, then boiling it in the liquid of hydroxide sodium of 2% concentration for 6 hours, (4) washing it to neutrality by using the water of pH=3, and soaking it in alum liquid of 10% concentration at the temperature of 70℃ for 24 hours, and (5) washing it by clear-water and drying it at the temperature of 80℃. For the modified clinoptilolite, the penetrability of interior pores and specific surface areas are augmented, and the adsorbability of fluoride is increased together with the decrease of silicon-aluminum ratio. Therefore, the high-energy of defluoridation is shown with the increasing ion-exchange capability of this modified zeolite.

Abstract:Abstract：The potable water endemic fluorosis (called endemic fluorosis disease for short) is an endemic disease caused by drinking water which has had excessive fluorine content for a long time. The main factors responsible for the endemic fluorosis disease are the specific natural environment, geological environment, living environment etc. This paper has discussed the geological environments in which the endemic fluorosis disease has occurred in Northeast China, investigated the problem on the endemic fluorosis disease prevention and given some advices concerning water improvement.

Abstract:Abstract：Exemplified by the demonstration area in Zhaoyuan County, this paper deals with the distribution of endemic fluorosis disease in Northeast China. In combination with hydrogeological conditions in disease areas, the authors have determined the endemic fluorosis-inducing aquifer and advanced the intent layer for water supply and the well drilling technology. All this has provided experience for water supply in Northeast China.

Abstract:Abstract：The content and distribution characteristics of F in soils in the whole region and the typical areas of the Zhujiang River delta were studied by contrast with the F background of soils in the Zhujiang River delta and whole China. Soil types, parent rocks and land use types affecting the above situation were analyzed in this paper, and the relations between F content of soils and endemic fluorosis were discussed. The results show that the F average value of surface soils and deep soils in the Zhujiang River delta is respectively 510 mg/kg and 529 mg/kg. The F content of the delta gleyed paddy soils, delta salinized paddy soils and irrigated land in Quaternary marine (continental) loose layer areas is the highest. The high F background areas of surface soils whose acreage is 6760 km2 are distributed in the central plain, the F pollution areas are spread in local areas of Dongguan, Xinhui and Zhuhai. The acreage of high F background areas of deep soils is 5504 km2, the F pollution areas are distributed in Gaolan island and Sanzhao island of Zhuhai City. The enrichment of F in soils is obviously related to Quaternary marine-terrigenous and terrestrial-marine facies sediments, and evidently has to do with granitoids in the bedrock. The soils influenced by human activity, paddy soils and their salinization seem to be beneficial to F enrichment . The endemic fluorosis in this region is distributed in Conghua, Zengcheng, suburbs of Dongguan, Naihai, Xinhui and Enping, where endemic areas are located in high F strata, rocks and soils. There exists excessive F in the crops growing in soils of high F background areas, and the F excessive rates and excessive times of crops in endemic areas are greater than those of crops in the non-endemic areas, suggesting that the proportion of bioavailable dose of F in soils in pollution areas is high, and F in soils has been migrated and enriched in agricultural products, which jeopardizes the quality of agricultural products. High F soils and crops in the study region caused by high F geological environment become factors responsible for endemic fluorosis.

Abstract:Abstract：This paper deals with the distribution regularity of fluorine and TDS in groundwater of Hulun Buir plateau, and probes into chemical characteristics of groundwater. Using special methods, the authors evaluated the safety of potable water. According to the distribution regularity of fluorine and TDS in groundwater and the results of the safety evaluation of potable water, the authors put forward some suggestions for the exploitation and application of groundwater.

Abstract:Abstract：To find out the distribution and formation conditions of high-fluorine groundwater in Dali County, Shaanxi Province, the authors made a systematic analysis from several angles, such as strata, weather, terrain and landform, hydrogeology and hydrochemistry. The results show that the high-fluorine groundwater is jointly controlled by terrain, landform and hydrogeology. Meteoric water brings fluorine element in rock and soil into groundwater through water-rock reaction during its infiltration and leaching, and such water is concentrated during the evaporation to form high-fluorine water. This research provides hydrogeological grounds for solving the problem of safe water drinking in Deli County.

Abstract:Abstract：In order to study the relationship between the endemic fluorosis disease and the geological environment in Dali County, Shaanxi Province, the authors carried out a detailed statistical analysis of the group of patients suffering from fluorosis, and collected groundwater, soil, crop and vegetable samples for the determination of fluorine content. It is found that fluorine content of loess and saline soil is lower than that of clay，but the water-soluble fluoride of the former is higher than that of the latter, and the higher the alkaline, the higher the ratio of water-soluble fluoride to perfluoro. Fluorine content of unit mass of vegetables such as spinach and Indian lettuce is higher than that of wheat and corn. Fluoride in groundwater is concentrated in areas where hydrodynamic action is weak and salinity is high. Such fluoride comes mainly from the primordial rock, loess and clay. Areas with severe endemic fluorosis are located at the edge of low-lying land and the conversion position from steep slope to gentle slope. High prevalence of fluorosis patients is not only related to fluorine content of atmosphere, crops and vegetables, but also associated with fluoride content of groundwater. Based on these characteristics, the authors suggest that the methods for preventing and controlling endemic fluorosis disease should lie in the strengthening of exploitation and consumption of low-fluoride groundwater as well as the growing of low-fluoride crops. In addition, physical and chemical means should be employed to reduce the fluorine content of groundwater so as to reduce the prevalence rate of the endemic fluorosis disease in this area.

Abstract:Abstract：With the aid of soil column test models, the transport regularity of fluoride in different polluted fluoride soils of Yuncheng basin was studied. The curves of F- concentrations in different periods and at different positions were obtained in different soils under the condition of inputting fluoride contaminants continuously. Laboratory experiments reveal that the migration process of fluorine ion in soils is complex because of its active chemical properties. The pH values of the soil solution change from neutral to alkaline due to the release of OH－resulting from the adsorption in the course of the experiment. The breakthrough curve of the fluorine ion is asymmetric due to the adsorption and desorption, and the peak values of concentration decay gradually at different positions. The tail of the breakthrough curve is relatively long. The migration distance in vertical direction is comparatively short, and hence it is very difficult for the F- ion to migrate directly from soil to groundwater through eluviation. The results are consistent with the observation data.

Abstract:Abstract：According to sources of fluorine in groundwater, fluorosis in Jilin Province can be divided into four types: 1. Deep-cycle hot water type: the fluorine in groundwater originates from the release of granite magma. Fluorine prevention in drinking water could be carried out by improving crevice-pore water in Neogene sediments and cave-crevice water in basalt. 2. Volcanic activity-enrichment groundwater type: the fluorine in groundwater originates from the release of magma during volcanic activity, and fluorine prevention could be conducted by improving crevice-pore water in Cretaceous sediments; 3. Displacement-enrichment groundwater type: the fluorine in groundwater originates from rock weathering and leaching, with the source from the Da Hinggan Mountains, eastern high plains and Songliao watershed. And it forms high fluorine groundwater when it moves into regional runoff-catchment area and regional catchment area. Fluorine prevention could be performed by improving crevice-pore water of Neogene Taikang Formation and Da’an Formation as well as Cretaceous Mingshui Formation, Sifangtai Formation and Nenjiang Formation. 4. Eluviation-enrichmert type: the fluorine in groundwater originates from the loessial soil and mild clay. Fluorine prevention could be implemented by improving crevice-pore water of Cretaceous Qingshankou Formation.

Abstract:Abstract：Endemic fluorosis related to domestic coal combustion is widely spread around Guizhou Province, but its source is still unclear. Analysis of samples of waters, coals and soils collected from Zhijin, Nayong and Pingba Counties where the disease is common reveals that the source of fluoride comes mainly from coals in areas where low quality coals or coals with high fluorine are exploited, and is derived from soils in other areas. Merely drinking water seems not likely to cause endemic fluorosis. It is therefore suggested that stopping the mining of low quality coal or coals with high fluorine and making use of near-surface soil could possibly relieve the damage of fluoride in the province.

Abstract:提要：20世纪，越来越多的证据使人们意识到，吸入含石棉的灰尘会使从事与石棉有关的几种职业（如石棉采矿、造船和石棉产品组装）的工人患上几种严重的呼吸道疾病（石棉沉着病，肺癌和mesotheliuma）。为此已经制定了若干规定，以控制工人们在特殊的制造、采矿和其他工作地点与石棉尘埃的接触。比较间接的是控制和管理“天然产生的石棉”（NOA），这一问题近年来也引起了管理机构、健康机构和居民团体的注意。NOA包括在自然状态下原地找到的被描述为石棉的矿物，例如在基岩或土壤中的这种矿物。NOA之所以引起关注，是因为如果含石棉的岩石受到自然侵蚀或人类活动（例如修路、城市开挖、农业、采矿、压碎和碾磨）的影响，就有可能暴露并变成空中尘埃的微小纤维。天然石棉矿床的规模差异很大，从薄的四散的细脉一直到大的矿体。它们的地理分布与地质条件直接有关。石棉产出的地质背景是含镁丰富的主岩，这些岩石受到低压低温的变质作用蚀变而成。已知的容矿主岩包括变质的和已被交代的超基性岩（尤其是蛇纹岩）、一些基性火成岩、变质白云岩和变质的铁建造。石棉形状的角闪石在几种热液蚀变型的碱性火成侵入体中也能作为副矿物存在。石棉形成于可预见和可鉴别的地质环境。这种认识是一种信息，而这种信息使公众健康机构可以执行有情报根据的屏蔽和管理规划。第一步是在区域的或国家规模的尺度上确定和描述已知的（报道过的）石棉矿床。第二步是对容纳已知石棉矿的单位进行填图，以划定可能的其他石棉矿化的范围。这种地质研究使有关机构对遇到石棉的可能性做出规划，而尽量节省在不太可能遇到石棉矿的地区的管理费用。对石棉地质条件的认识可以事先应用于岩石和土壤的挖掘项目，而不管挖掘的规模有多大。这种对石棉管理的科学探索能有助于缓解对挖掘所发现的自然石棉矿床的连续不断地做出反应。因此，通过对很可能含有石棉矿床的地区做填图，规划者可开发出一些控制尘埃的程序，这些程序适用于工人和附近居民最容易暴露于空气携带的石棉的地区。

Abstract:提要：目前，西孟加拉地区地下水砷污染问题日益严重并且已经波及到食物链中。由于吸收了砷污染地下水，谷物和蔬菜中砷含量日渐累积，超出了健康规定范围。尽管提出了若干补救方案，但是考虑到农业人口的社会经济状况，建议使用地表水灌溉方案。然而，实际中该方案仍然较难施行，且并无其他更经济有效的措施。若干年后，含水层可以减缓严酷的健康环境现状并为人们提供安全的饮用水。

Abstract:提要：研究表明饮用水中微小数量的砷会对人类健康产生不利影响。世界上居住在贫穷地区的人数超过了100万，目前他们正直接饮用来自含水层中砷离子含量（> 10μg/L）非安全标准的地下水。砷有时称为毒中之王，在水环境中常常以五价氧化物形式出现。自2000年以来，许多国家开始执行更为严格的10μg/L（WHO认可的居民安全饮水标准）饮用水标准，可以确定地说，在世界范围内的饮用水中检测到砷的情况越来越多。亚洲地区砷中毒的人数比世界其他地区总和还多。最受影响的地区位于南亚和东南亚富砷带，环绕恒河—雅鲁藏布江—梅克纳河三角洲及恒河平原上游的冲洪积扇含水层、红河三角洲、湄公河和伊洛瓦底江；在中国境内包括内蒙黄河冲积盆地，山西大同盆地、新疆准噶尔盆地，其中的地下水富含砷和氟化物而引发砷中毒和氟中毒。尽管还未完全掌握其中的水文地质及生物地球化学作用的详细过程，但对大多数沉积介质含水层，在还原条件下砷离子容易从沉积介质转移到地下水中。孟加拉研究实例表明地质时期尺度的冲刷降低了沉积介质中的As和有机物含量从而形成低砷地下水。这一认识为孟加拉国的降砷策略提供了科学指导，是未来水文学，矿物学，地质学和生物地球化学方面很有意义的研究方向，并有利于地砷病区低砷地下水的可持续利用。

Abstract:提要：1990年报道了在中国内蒙古河套平原由于饮用污染的地下水而患砷中毒的病例。估计目前内蒙受到砷中毒影响的居民已超过41万人。从1997年至2004年, 在长达8年的时间里, 我们进行了水文地质调查、地质调查和医学调查, 并装置了管道输送的供水系统。这些调查揭示了河套平原地下水受砷污染的机理: 由于被吸收的砷释放进入地下水, 蓄水层中不断加强的还原环境造成铁氢氧化物的溶解。 为了防止砷中毒病人数量的进一步增加, 停止饮用污染过的水和供应安全的饮用水是重要的。 我们需要根据当地的地质和水文地质条件来了解砷污染的机理。

Abstract:提要：从医学地质学角度看，在日本地质污染的地方如何使用地下水资源，我们面临许多问题。本文讨论了地质污染学（geo-pollution science）作为医学地质学中一门学科的概念以及在受二苯亚砷酸污染的地方成功使用农业地下水的案例。

Abstract:Abstract：This paper has analyzed the distribution, hydrogeological condition and hydrochemical characteristics of the drinking water type arseniasis in northern Yinchuan plain, and dealt with the distribution and enrichment environment of arsenic ions in groundwater. It is shown that the high arsenic groundwater is distributed in two zones in the alluvial lacustrine plain, and is mainly of unconfined water, with the buried depth of the groundwater table less than 40 m. The high arsenic groundwater is in a weakly alkaline and reducing environment, and the hydrochemical types are mainly HCO3-Na·Ca, Cl·HCO3-Na and Cl·HCO3-Na·Ca; This paper also makes a comparative study of the distribution and the environment geological features of high arsenic groundwater areas in northern China, which include Hetao plain in Inner Mongolian, Datong basin in Shanxi province, Xinjiang, and western Jilin Province.

Abstract:Abstract：A study area in Jilin was selected from lots of arsenic endemic regions, which are mainly distributed in Taiwan, Xinjiang, Inner Mongolia, Shanxi and Jilin. The area is physiogeographically located along the western flank of Songnen plain, and hydrogeochemically regarded as a basin with groundwater generally flowing eastward. A total of 196 groundwater samples were collected, which not only covered the whole study area but also extended to different depths/aquifers that included Quaternary phreatic groundwater, Quaternary Baitushan Formation confined groundwater and Neogene confined groundwater. Cluster analysis was also performed to identify the degree of relationship between each chemical constituent and arsenic by the SPSS statistical package. The result reveals that the distribution of arsenic at the present time has a close relationship with the spatial variation of Fe, Mn as well as Cl-, PO3-4, HCO-3, SO2-4 and Se. An inverse geochemical model was established to demonstrate the above relationship by using the PHREEQC software. The simulation results have confirmed that the arsenic presence and its distribution in the groundwater of this area result largely from the leaching-migration-accumulation from the edge to the central area of the basin. The dissolution of the redox sensitive ferric oxide compounds and hydrous ferric oxides as well as the arsenic compounds (arsenate or arsenide) is probably the major mechanism for the control of the spatial variation of arsenic in the study area. As groundwater flows stagnantly in the low-lying central area, the afore-mentioned minerals become less stable due to lower Eh and move into the groundwater with relatively high solubility under the lower Eh condition. At the same time, the arsenic complexes adsorbed by these minerals are released and migrate with the movement of the groundwater. It is concluded that the presence of arsenic in the regional groundwater flow regime exhibits the highest concentration in chloride-sodium bicarbonate groundwater in the central area, which is consistent with the above findings and many previous studies in this special field of the international community.

Abstract:Abstract：Geogenic high arsenic groundwater occurs in Datong basin, northern China. This paper reports the results of recent studies of high arsenic groundwater in Datong, which include spatial distribution of high arsenic groundwater, hydrochemical evolution, source of arsenic, and geochemical processes controlling the mobilization of arsenic. Carboniferous-Permian coal-bearing clastic rocks around the basin may constitute the primary sources for arsenic in groundwater. Iron-bearing magnetic minerals are the main carrier of arsenic in the aquifer system and organic matter-enriched lacustrine sediments is the secondary source for arsenic in groundwater. In the central part of the basin, groundwater permeation is very slow and evaporation is the major way of groundwater discharge. Intensive evaporation results in the increase of TDS content. Decomposition or oxidation of organic carbon in aquifer sediments is catalyzed by bacteria and/or microorganisms, resulting in prevalence of anoxic conditions. Under high pH and low Eh conditions, due to the adsorption of arsenic by iron or/and manganese oxyhydroxides and the decrease of clay minerals, part of arsenic absorbed on the surface of these minerals tends to be released from sediments during this process. On the other hand, iron and manganese oxyhydroxides with strong adsorbing capacity for arsenic are reduced to low valence states which are soluble under low Eh conditions, so arsenic adsorbed on their surface is released to groundwater. Under anoxic conditions, dissolved SO2-4 and organic carbon can be reduced to produce H2S and CH4. Although dissolved arsenic can be removed from groundwater via the reaction with pyrite due to FeAsS precipitation, the low concentration of dissolved iron and sulfate in groundwater may limit this reaction. When sulfate is used up, methanogens will prevail the biogeochemical processes and further promote the enrichment of arsenic in groundwater. In addition, pH increase induces desorption of a wide variety of oxyanions, such as phosphate, vanadate, uranyl and molybdate, which tend to accumulate in the groundwater. Competitive adsorption of these oxyanions with arsenic can result in the release of arsenic from sediments into groundwater

Abstract:Abstract：The Hetao plain of Inner Mongolia is one of the serious endemic arsenic poisoning areas in the world. The authors took Hanggin Rear Banner in western Hetao plain as a typical study area, where endemic arsenic poisoning constitutes a very severe problem. Studies show that As concentration is 7.7-34.6mg/kg in sediments of the high As groundwater area and As concentrations are relatively high in clay and mild clay. According to the results of the authors’ investigation, As is incorporated in amorphous iron oxides and is associated with sulfides and targeting acid volatile sulfurs, carbonates constitute the main association of sedimentary As, accounting for over 50% of total As. pH values of high As groundwater are 7.0-8.3, average Eh value is -155.1mV, average TDS value is 1.58 g/L, main hydrochemical types are Cl-HCO3-Na, Cl-Na and HCO3-Cl-Na, and As concentration ranges from 15.5 to 1093μg/L and is mainly represented by As(Ⅲ), high level DOC (0.73-35.76mg/L), HCO-3(283.75-1290.48mg/L), NH+4(0.27-10.48 mg/L) and minor nitrates and sulfate. Hanggin Rear Banner is also one of the serious endemic fluorosis areas, with fluoride content being 1.11-6.01mg/L in high F groundwater. Due to the presence of excessive As in most high F groundwater areas, there exists a coexistence phenomenon of high F groundwater and high As groundwater. A comprehensive analysis shows that high As groundwater was formed in a reductive environment in Hetao plain. Under reducing conditions, the reductive dissolution of Fe/Mn oxides (or hydroxide) from sediments in high As areas can release arsenic into groundwater. This is the main factor responsible for the formation of high As groundwater in the study area.

Abstract:Abstract：Kaolin and siderite activated by KOH were adopted as the main raw materials, the peanut shell acidified by phosphoric acid served as the pore-forming material, and then arsenate-removing material was obtained by the high-temperature activation method. The performance of the arsenate-removing material under the condition of normal temperature and pressure was studied in orthogonal captive adsorption tests. The results show that, when weight ratio of the kaolin, siderite and peanut shell was 2∶2∶1, KOH concentration was 0.3 mol/L, soaking time was 6 h and activation temperature was 900℃, the removal efficiency of arsenate was the best, even attaining to 95%. The adsorption material was filled in a plexiglass column 40mm in diameter and 450mm in length for dynamic continuous adsorption experiments. The results show that the material could maintain an effective removal of arsenate for 20 hours or so and the removal efficiency of arsenate could reach 84%. The adsorption behavior meets the Langmuir isotherm.

Abstract:Abstract：High iodine water is harmful to human health. High iodine groundwater is distributed around arid and semi arid inland basins, fluvial plains and coastal areas, which cover 12 provinces and autonomous regions in China. Huanghuaihai plain is a major region of high iodine groundwater. This paper points out that the source of iodine in groundwater is derived from the sea and brought in through atmosphere cycle, so iodine in the coastal aquifer, such as coastal aquifer of Huabei plain and that of Huaihe river plain, is usually high. The aquifer composed of alluvial and lake deposited materials with rich organic matter, ferric oxide and aluminum oxide often has high iodine, and the weathering crust of limestone possesses strong adsorption capacity for iodine. At last, this paper gives some suggestions for modification of iodine indexes in Groundwater Quality Standard（GB/T14848-93）》of China.

Abstract:Abstract：The distribution of endemic diseases has a close relationship with various geological environments such as topography and relief, geological structure, strata and lithology, soils, and hydrogeological conditions. Based on the data obtained from endemic investigation and eco-geochemical investigation in the lower Yellow River basin of Shandong Province, the authors studied the relationship between the endemic goiter induced by excessive iodine and the geological environment in the aspects of relief, soils and potable water. The results suggest that endemic goiter has high positive correlation with iodine content in water but has no correlation with iodine content in soils. In view of preventing and treating endemic goiter, the authors put forward some suggestions concerning the prevention of endemic goiter and the improvement of the environmental geological situation.

Abstract:Abstract：The study area is located in southwest Taiyuan basin of Shanxi Province. Totally 950 water samples were collected from the shallow wells (≤50 m), middle wells (50-200 m) and deep wells ≥200 m) . With ICP-MS and HPLC-ICP-MS methods, the authors determined the total iodine content and inorganic iodine content, which included iodine ion and iodine acid radical (I- and IO-3). The results indicate that the proportions of iodic concentration that exceeds the standard are 76.8%, 70.3% and 85.2％ in groundwater of three layers, respectively. The highest iodic concentration in the shallow groundwater is up to 4117μg/L, which is 27 times higher than the national standard of drinking water (150μg/L). The main form of iodine in the groundwater is ionized iodine, with small amounts of iodate. About 60% water samples have organic iodine. The main causes for high iodine concentration in groundwater are special topography and aquifers in the study area, which results in hindered movement of groundwater. Furthermore, local agricultural irrigation using the middle or deep layer groundwater and salinization of surface soils in the low-lying lands has led to the increase of iodine in the shallow layer groundwater. Iodic source in groundwater is closely related to geological environment of marine, lacustrine and fluvial sediments. The results could offer scientific means to reforming water projects in high iodic water areas of China.

Abstract:Abstract：In this study, the authors investigated the hydro-chemical features and distribution of predominant constituents and ions in the groundwater of western Hetao Plain, Inner Mongolia, based on field survey and analyses of 400 water samples. The results indicate that the groundwater quality is generally not satisfactory because the densities of As, Cl-, SO2-4, TDS, total hardness, F- and Fe are in excess of the standard levels. Hydrochemical types in the study area are mostly Cl-HCO3-Na, Cl-Na, and HCO3-Cl-Na. Predominant components such as As, P, Fe, Cl-, F-and SO2-4 are distributed along the boundary of the alluvial and proluvial fans in the northwest of the study area and the alluvial plain with lower topography as well as Langshan Town in northern Linhe area. Furthermore, this study presents the correlations of all the 14 tested constituents based on methods of correlation analysis and multi-variable linear regression. It is shown that the relations between P, Fe and As are significant.

Abstract:Abstract：Endemic diseases in the lower Yellow River basin of Shandong Province, such as epidemic fluorine disease and endemic goiter, have impaired human health and economic development. Based on an investigation of the epidemic fluorine disease, endemic goiter and endemic arseniasis in four counties, in combination with the result of the eco-geochemical environment investigation, the authors studied the distribution and transformation of fluorine, iodine and arsenic in soils, potable water and crops. A comprehensive analysis of the relationship between eco-geochemical characteristics and endemic diseases was carried out. The results suggest that the epidemic fluorine disease has high positive correlation with fluorine content in soil and water. High content of iodine in water is the main cause of endemic goiter. The cause of endemic arseniasis remains unclear. According to the result of correlation analysis, this paper suggests canceling the supply of iodized salt in the high iodine area.

Abstract:Abstract：Micro-humic acid in drinking water can form stable complexes with heavy metals in the water, which might affect the modes of occurrence, movements and transformations of heavy metals. It is thus important to measure the content of humic acid in the water for assessing the relationship between the geological environment and the endemic disease. There exist quite a few measurement techniques for humic acid in the laboratory, but most of them are not suitable for rapid detection in the field. On the basis of analyzing characteristics of every detecting means, the authors put forward the colorimetry for detecting the humic acid in the water. Ports-15 spectrometer with 1cm optical fiber color comparison probe and 650nm wavelength red light was used in the laboratory for the test,. As a result, the curve for the relationship between the thickness of the humic acid and the absorbency was drawn.

Abstract:Abstract：For the purpose of detecting the formation condition, occurrence regularity and chemical characteristics as well as the recharge, runoff and drainage characteristics of groundwater, the building of monitoring well for sample collection is necessary. This paper deals with construction materials, well completion technology and sampling techniques, and presents the optimization of PVC-U well pipe and gravel filter as well as the differential shut of water and stratified sampling of monitoring well in the endemic disease area. Typical groundwater samples are collected through the depth preset sampling and double-packer systems.