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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
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In a study of 291 mineral waters from 41 different countries, 9–20% exceeded the Dutch drinking water standards for chloride, calcium, magnesium, potassium, sodium, sulphate, and fluorine. The mineral water quality cannot be qualified as bad because the standards for these compounds (with the exception of fluorine) are not based on health issues, but matters regarding undesirable taste and possible adverse effects on the water supply system. For the mineral water data set, the amount of dissolved compounds, hardness, and chloride content appear to be the most distinctive criteria. A mineral water type classification based on these criteria will offer consumers a tool for assessing mineral water on the basis of the chemical composition data on the bottle label. In terms of the criteria mentioned, average Dutch tap water strongly resembles the Belgian and Dutch mineral waters. This similarity does not extend to the price, since Dutch tap water is about 500 times cheaper. 相似文献
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露水的形成及其对土壤水分的影响是进一步量化水循环和生态水文过程的重要依据。为探明露水发生规律, 在宁夏中部干旱带连续3 a观测了每30 min气象资料和表层土壤水分, 用叶片湿度传感器测算了露水量。结果表明: 该区年露水量可达56.41 mm, 75%发生在6—10月, 最大月露水量和日露水量分别为13.40 mm和0.80 mm, 主要发生在03:00—08:00;露水发生的气温、相对湿度和风速范围分别为0~24.4℃、50%~100%和0.16~1.74 m/s, 风向为30°~60°(东北风)和270°~330°(西南偏西风); 气温和露点差与相对湿度之间呈极显著线性逆相关, 气温和露点差小于3 ℃且相对湿度大于80%时极易产生露水; 日露水量为0.6 mm、0.7 mm和0.8 mm时表层5 cm土壤贮水量可分别提高0.10 mm、0.20 mm和0.25 mm。该地区年均降露量是降雨量的13.5%, 露水年均发生频率为126 d(35%), 是当地水循环和生态系统不可忽略的水源。 相似文献
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北京大兴区第四系高氟地下水分布规律研究 总被引：2，自引：1，他引：1
北京市大兴区供水以地下水为主,研究该区高氟地下水的分布规律及其成因,对指导区域地下水的开发利用和保障居民饮水安全是必要的。在野外调查和以往研究成果的基础上,测试了北京大兴区地下水氟离子浓度。结果表明,高氟水分布区地层岩性以粘性土为主;浅层高氟水主要分布在大兴区的南部及东南部,超标区面积为258.57 km2;深层高氟水主要分布在中部,超标区面积为20.91 km2。建议对浅层高氟地下水加大止水深度,统一并严格设计饮用水井结构;对深层氟超标水,避免饮用或采取降氟措施后再饮用。 相似文献
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采空区是高氟矿井水形成的关键区域,其水-岩系统中氟的来源与溶解释放决定了矿井水中氟的富集或贫化。针对蒙陕接壤区3-1煤采空区矿井水氟来源及释放规律不清晰问题,采用水化学测试、岩石矿物成分分析、矿物扫描电镜与能谱检测,以及室内水-岩作用仿真模拟试验,查明矿井水氟物质来源与赋存载体,揭示岩石中氟释放规律。结果表明：研究区3-1煤矿井水水化学类型主要为HCO3-Na与SO4-Na型,3-1煤采空区矿井水氟浓度高于3-1煤生产工作面的矿井水浓度,且采空区矿井水pH、Na+/Ca2+浓度比均大于工作面矿井水。3-1煤采空区矿井水F-的物质来源为泥岩与粉砂岩,2种岩石中氟平均含量分别为741、610 mg/kg,氟在固相中的主要赋存载体为蒙脱石、高岭石、伊利石及绿泥石。采空区水-岩系统中氟的释放受岩性、粒径、pH、温度及Na+/Ca2+浓度比5个因素影响。其中,泥岩及粉砂岩中的氟比细砂岩中的更容易释放进入水中;无论何种岩性,随着粒径的减小,氟释放F-的浓度增大;此外,碱性、高温及高钠低钙的... 相似文献
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近40a来江河源区生态环境变化的气候特征分析 总被引：69，自引：12，他引：57
利用月气象资料,对过去40a江河源气候变化特征进行分析,并与全球、全国、青藏高原进行了比较.结果表明:江河源区气温具有增暖趋势,近40a两地年平均气温分别增加约0.8℃和0.7℃,为高原异常变暖区.黄河源区变暖的主要特征是最低气温变暖,日照时数增加;最低、最高气温的显著变暖,以及较黄河源区增加更长的日照时数是长江源区变暖的主要特征.长江源区冬季变暖的作用不是主要的,春季、夏季和秋季的变暖作用比冬季还要大;黄河源区的变暖也并不主要是冬季变暖造成的,秋季变暖的作用与其相当,其它季节的变暖作用也不能忽视.近40a来江河源区降水量略有增加,主要体现在20世纪80年代中后期以来春季与冬季降水量的明显增加,夏季降水量虽然总体上没有明显变化,且局地夏季降水量呈持续减少趋势.与全球、全国以及高原区对比显示,江河源区对全球气候变暖的响应最敏感,变暖首先从长江源和整个高原发端,之后15a.黄河源和全国才进入显著温暖期.黄河源与长江源北部降水量的增加表明,气候变暖有利于高原增加降水量. 相似文献
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Anthropogenic gadolinium as a microcontaminant in tap water used as drinking water in urban areas and megacities 总被引：1，自引：0，他引：1
Serkan Kulaks?zMichael Bau 《Applied Geochemistry》2011,26(11):1877-1885
Gadolinium chelates have been used since 1988 as contrast agents in magnetic resonance imaging (MRI), and produce positive anthropogenic Gd anomalies in rare earth element (REE) patterns of river and lake waters. These Gd compounds are not removed in wastewater treatment plants (WWTP) due to their high stabilities, and are transferred to surface waters with the clearwater discharge from WWTP. Through natural and induced bank filtration, the anthropogenic Gd is also transported into groundwater. To date, there are no related acute health risks known, but the potential long-term effects of exposure to low doses have not been studied.Here REE data is presented for tap water from the City of Berlin, Germany, a metropolitan area that is known for its anthropogenic Gd-rich rivers and groundwater. Natural and induced bank filtration play important roles in Berlin’s freshwater resource management. Therefore, the extent to which municipal tap water that is used as drinking water is affected by anthropogenic Gd was investigated. Large positive Gd anomalies were found in tap water samples from the western districts of Berlin, indicating the presence of up to 18 ng/L of anthropogenic Gd on top of a geogenic background of 0.54 ng/L. In marked contrast, the amount of anthropogenic Gd in tap water from the eastern districts of Berlin is negligible to minor (maximum of 0.18 ng/L on top of a geogenic background of 0.26 ng/L). This strong regional difference likely results from the specific historical situation of Berlin, where before the re-unification of Germany in 1990, natural and induced bank filtration were necessities in isolated West Berlin, but unimportant in East Berlin, a situation that has seen little change during the past 20 years. Thus, drinking water resources in the western part of Berlin are more strongly affected by anthropogenic Gd than those in the eastern part. The high anthropogenic Gd concentrations found in some tap waters in Berlin clearly show that the Gd initially used as contrast agent is removed neither during natural nor artificial water treatment. This is further evidence for the high stability and long environmental half-lives of these compounds. Considering that the amount of anthropogenic Gd in the Havel River in Berlin has increased more than 4-fold over the past 15 years and that water migration from the Havel River to the groundwater wells take years to decades, the amounts of anthropogenic Gd in West Berlin tap water will increase further over the next few years. Due to its presence in tap water that is consumed as drinking water, millions of people are exposed to low doses of these anthropogenic Gd chelates. Additional data for the City of London, UK, for example, indicate that this is not a local phenomenon confined to the City of Berlin, but rather a common feature of tap water in metropolitan areas and megacities in countries with highly developed health care systems. Hence, the REE distribution in tap waters used for human consumption should be monitored, especially since the anthropogenic Gd chelates can also be used as tracers for emerging microcontaminants such as steroids, pharmaceuticals and personal care products. 相似文献
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We collected a total of 50 water samples comprising tap water, ground water, and bottled water, from various areas of Jeddah City. We collected tap water samples from 25 districts, groundwater samples from 10 wells, and 15 different brands of bottled water. The levels of 28 elements were determined by inductively coupled plasma mass spectrometry (ICP-MS). Water certified reference material (CWW-TM-B) was used to ensure quality assurance. Recoveries ranged from 92 to 104.8% for all measured elements. Levels of major and trace elements in groundwater samples were higher than those in both bottled and tap drinking water. Only four elements (Al, Cs, U, and Zn) were shown to be higher in tap water samples than other samples type. However, their values were far below the guideline values. All mean concentrations of Na, K, Mg, and Ca in well water samples were significantly (p < 0.05) higher than those in both bottled and tap drinking water. In addition, only Al and Zn in tap water samples were significantly (p < 0.05) higher than those in both bottled and well drinking water. Most of the other elements were higher in well water samples compared to other sources. The results from this study will be used to increase public awareness about the safety of drinking water. It will also be useful for increasing awareness of health issues related to drinking water and to water used for other purposes. 相似文献
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饮水氟化预防龋齿及其在中国的实践 总被引：7，自引：0，他引：7
龋齿目前已成为严重危害我国人民健康的口腔疾病。国内外大量研究与观察证明饮水氟化是最安全、投入产出比最佳的预防龋齿的公共卫生措施。在广州，1965年开始进行饮水加氟试点，龋病发病率曾降低约50％，停止加氟后，龋病发病率再次上升。目前广州已成为全国龋病病情最为严重的城市。考虑到随着人民生活水平的提高，食品中的糖增加而粗纤维减少；随着经济的发展，水资源严重不足，城市供水正由以含氟较高的地下水为主转为以含氟较低的地面水为主，这种趋势将使我国龋病问题日益严重。在牙医严重不足，公众缺乏口腔卫生、牙齿保健知识的情况下，饮水加氟是最安全、有效、经济的防治措施。推广饮水加氟的工作，应当在科学研究和公众参与下，积极稳妥地进行。 相似文献
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综述了生活饮用水水质处理技术如饮用水水质标准、水源水水质处理标准、饮用水出厂水质处理、管网水质研究、末梢水质净化研究的进展,并指出今后应加强的改进建议。 相似文献
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Enn Karro Ene Indermitte Astrid Saava Kadri Haamer Andres Marandi 《Environmental Geology》2006,50(3):389-396
A study was undertaken to examine the content and spatial distribution of fluoride in drinking water. Water samples (735) from public water systems covering all Estonian territory were analysed using SPADNS method. In order to specify the natural source of fluoride, the chemistry data from five aquifer systems utilised for water supply were included into the study. Fluoride concentrations in tap water, to a great extent, ranged from 0.01 to 6.95 mg/l. Drinking water in southern Estonia, where terrigenous Middle-Devonian aquifer system is exploited, has a fluoride concentration lower than recommended level (0.5 mg/l), thus promoting susceptibility to dental caries. The western part of the country is supplied by water with excess fluoride content (1.5–6.9 mg/l). Groundwater abstracted for drinking purposes originates from Ordovician and Silurian carbonate rocks. The content of fluoride in Silurian–Ordovician aquifer system is associated with the groundwater abstraction depth and the main controlling factors of dissolved fluoride are the pH value and the chemical type of water. 相似文献
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Providing clean and good quality water is essential for sustaining human health and life, and for ensuring the preservation of ecosystems. The purpose of this paper is to identify the chemical and microbiological characteristics of drinking water source of Cankiri City (as raw and purified) and tap water samples of central Cankiri and its towns. The water quality in Cankiri Province was evaluated by comparing these parameters with permissible limits set by Turkish legislation and World Health Organization (WHO). Raw and purified water samples were analyzed for chemical and microbiological qualities, trace metal, pesticide, polycyclic aromatic hydrocarbon (PAH), trihalomethane (THM), and benzene contents. These analyses indicated that the parameters exceeded those of the Turkish legislation (phenolic substance, biochemical O2 demand, Mn, Se, fecal coliform) and the WHO guidelines (pH, phenolic substance, Cd, Se, fecal coliform). In this study, tap water samples were also collected from 50 sampling sites from central Cankiri and its towns during 2010. In these samples, chemical characteristics (bromide, free chlorine, nitrate and nitrite), carbamate, herbicide and fungicide contents, and microbiological contaminants were investigated. In the tap water samples, it was found that free chlorine concentrations exceeded the Turkish guidelines. Escherichia coli, total coliform and enterococci were used as indicators of possible sewage contamination due to inappropriate water distribution. Our results also indicated that significant microbiological contaminations in the tap water samples were above the guidelines for drinking water given by the Turkish legislation and WHO, and might pose a health risk. This investigation of drinking water samples of the Cankiri Province would point to the need of a new drinking water treatment strategy to ensure the safety of consumers. 相似文献
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为了研究赤泥中氟向下运移过程中的影响因素,根据堆场周围的水文地质条件,设计了7组动态淋溶试验,并对试验数据进行了灰色关联度分析。结果表明,排放7天后的赤泥其表面下700 mm处的温度仍达78℃,而刚排放到堆场的冲灰水温度更高,可达87.5℃,高温赤泥和冲灰水有利于氟的迁移;赤泥的pH值为10.29～11.83,浸出液的pH值为12.00～13.20,碱性很大,致使氟易随水迁移;赤泥的其它污染组分,如总硬度、Cl-、SO42-、K+、Na+、Ca2+、Mg2+,均对氟的迁移有一定的影响,且Na+、SO42-和Ca2+为主要控制因素,即溶液中Na+、SO42-、Ca2+含量越高,赤泥中的F-离子越易淋出。 相似文献
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High fluoride groundwater occurs in Maku area, in the north of West Azarbaijan province, northwest of Iran. Groundwater is
the main source of drinking water for the area residents. Groundwater samples were collected from 72 selected points including
40 basaltic and 32 nonbasaltic springs and wells, in two stages, during June and August 2006. The areas with high fluoride
concentrations have been identified, and the possible causes for its variation have been investigated. Regional hydrogeochemical
investigation indicates that water-rock interaction is probably the main reason for the high concentration of ions in groundwater.
The concentration of F− in groundwater is positively correlated with that of HCO3
− and Na+, indicating that groundwater with high HCO3
− and Na+ concentrations help to dissolve some fluoride-rich minerals. All of the water samples, collected from the basaltic areas
do not meet the water quality standards for fluoride concentration and some other parameters. Hence, it is not suitable for
consumption without any prior treatment. Inhabitants of the area that obtain their drinking water supplies from basaltic springs
and wells are suffering from dental fluorosis. The population of the study area is at a high risk due to excessive fluoride
intake especially when they are unaware of the amount of fluoride being ingested due to lack of awareness. 相似文献
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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
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气候变化对中国西北地区山区融雪径流的影响 总被引：22，自引：16，他引：22
选择祁连山黑河流域作为中国西北地区山区积雪流域的典型代表，分析了1956－1995年40a以来气候，积雪变化的状况和特点以及春季融雪径 波动趋势，利用融雪径流模型（Snowmelt Runoff Model-SRM)和卫星遥感数据模拟气温上升框架上的融雪径流变化情势，结果表明，中国西北地区山区的气候变化主要表现在年平均气温的缓慢上升而降水基本平稳，年内气温的上升幅度以1－2月份比较强烈，而3－6月融雪期的气温并没有大的变化，导致融雪期在时间尺度上的扩大，融雪径流呈慢增加趋势且受径流周期变化控制，融雪径流峰值的时间上前移。 相似文献