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Organic matters in drinking water of Kaschin-Beck disease areas were extracted. Then analyses and characterization were performed by means of multiply chemical and physical methods. The results did not show the obvious difference in the frame structure of humic substances and the structure of rmcromolecular compounds in the drinking water of disease and non-disease areas, but the difference in the contents of some micromolecular compounds and radicals. The investigation also includes the preliminary research on the photoreaction of drinking water from disease and non-disease areas and the accumulation of natural organic matter in the bone of tested animals. 相似文献
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大骨节病(Kaschin-Beck disease)至今原因不明。在众多病因学说中,饮水有机物中毒说,粮食霉菌感染说和地球生物化学说较为受到重视。但都因流行病学研究和环境生态学考察结果不一致,更因缺少实验论证而未为人们所确认。 相似文献
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Zhang Xuelin Ren Shufen Li Wencheng Wang Wensheng Wang Jin Wang Wenjun Zhang Yuxia 《环境科学学报(英文版)》1991,3(4):102-107
The relationship between humic acid and selenium content was studied in this research. The results of calculation showed that there is more humic acid and less selenium in Kaschin-Beck disease areas in China. Fulvic acid in soil could increase selenium level in plants. The chemical bonding between humic acid and selenium was observed with an I.R. spectroscope. It was remarkable for the changes of absorption peak and frequency in 1100-1000 cm-1, 900-700 cm-1. 相似文献
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Kaschin-Beck disease (KBD) could be exogeneous free radical induced endemic osteoarthropathy under conditions of lacking necessary antioxidant defences.especially selenium-cored defence in Chinese eco-en-vironment. Experimental evidences have been provided for the internal relations among previously suggested pathologic factors, i.e., selenium deficiency, organic matters of drinking waterand mycotoxins from contaminated grains, based on the facts that the former is a preventory factor while the others are exogenous freeradical carriers. ESR spectrum shows that these exogenous free radical carriers have a property of semi-quinone compounds and are toxic in in-vitro cartilage cell culture and animal tests in inducing lipid peroxidation process. 相似文献
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In order to provide further references for studing on the causes of Kaschin-Beck discase (KBD) and measuring for its prevention and treatment from a macroscopic view, we analyzed the natural growth and declineof KBD and the effects of selenium and humic acid on its occurrence from an epidemiologic angle. In this article through a retrospective survey on the spots of disease areas by comparison between a change in water sources and that without. It was proved that a change in water sources was an effective measure for the prevention of KBD occurrence, and the pathogenic factor of KBD was one (or several kinds) of organic compounds or active radicals related to water. 相似文献
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This paper deals with some endemic diseases related to selenium, iodine and fluoride in eco-environment. Keshan disease and Kaschin-Beck disease are associated with low selenium, they mainly occur in a belt zone across China ranging from North-East to South-West. Selenium contents in food grains and human hair from the disease affected areas are usually below 0.020ppm and 0.20ppm respectively. The endemic goitre caused by iodine deficiency distributes extensively in China, mainly in mountainous and hilly districts, swamp and peat areas, some sand soil and limestone areas. Also there is another kind of endemic goitre which caused by iodine excess in interior and coast areas. Endemic cretinism usually occurs in the endemic goitre seriously affected areas. Endemic fluorosis is also widely distributed in China, but mainly occurs in dry or semi-dry areas of north China. The fluoride sources for causing endemic fluorisis are drinking water and food grains polluted by coal smoke in the backing process of maize 相似文献
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This article focused on the influences of fulvic acid and humic acid on aluminum speciation in drinking water. Factors including
the concentration of residual chlorine and pH value had been concerned. Aluminum species investigated in the experiments included
inorganic mononuclear, organic mononuclear, mononuclear, polymer, soluble, and suspended forms. It was found that the e ects of
fulvic acid and humic acid on aluminum speciation depended mainly on their molecular weight. Fulvic acid with molecular weight
less than 5000 Dalton had little influence on aluminum speciation; while fulvic acid with molecular weight larger than 5000 Dalton
and humic acid would increase the concentration of soluble aluminum significantly even at concentration below 0.5 mg/L (calculated
as TOC). Aluminum species, in the present of fulvic acid with molecular weight larger than 5000 Dalton and humic acid, were more
stable than that in the present of fluvic acid with molecular mass less than 5000 Dalton, and varied little with reaction time. Within pH
range 6.5–7.5, soluble aluminum increased notably in water with organic matter. As the concentration of residual chlorine increased,
the e ects of fulvic acid and humic acid became weak. The reactions between humic acid, fulvic acid with large molecular weight, and
aluminum were considered to be a multi-dentate coordination process. With the consideration of aluminum bioavailability, reducing
the concentration of fulvic acid and humic acid and keeping the pH value among 6.5–7.5 were recommended during drinking water
treatment. 相似文献
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中国“硒与健康”数据库应用研究 总被引:9,自引:0,他引:9
由“硒与健康”数据库数据研究表明,中国26个省市人发含量量均值与长寿水平间存在着大致线性关系,相关系数达到0.71。135种常用食品含硒量与品种有关,鱼肉禽蛋>油料>豆类>粮食>蔬菜>水果。对克山病、大骨节病病区与非病区环境硒样品数据模式识别处理表明。环境硒水平不足是患病的根本原因之一,而主食大米与否不是本质原因。 相似文献
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Peng An Xu Langqiu Research Center for Eco-Environmental Sciences Academia Sinica Beijing China 《环境科学学报(英文版)》1989,(2)
The relation between EH [Se(VI)/Se(IV)] and pH of soil aqueous extract in Kaschin-Beck disease region and the effects of natural redox agents, namely humic substances, MnO2 and Fe2+, on the redox property of the system were studied. The results indicated that both humic acid and Fe2+ could enhance the reducibility of Se(VI) and MnO2, a limited oxidizability for Se(IV). Fe2+ showed a weak reducibility only at low pH value. The reducibilities of three sulfur-containing compounds for Se(VI) were in following order:thioglycollic acid > L-cysteine > sulfide 相似文献
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Effects of advanced oxidation pretreatment on residual aluminum control in
high humic acid water purification 总被引:2,自引:0,他引:2
Due to the formation of disinfection by-products and high concentrations of Al residue in drinking water purification, humic
substances are a major component of organic matter in natural waters and have therefore received a great deal of attention in recent
years. We investigated the effects of advanced oxidation pretreatment methods usually applied for removing dissolved organic matters
on residual Al control. Results showed that the presence of humic acid increased residual Al concentration notably. With 15 mg/L of
humic acid in raw water, the concentrations of soluble aluminum and total aluminum in the treated water were close to the quantity
of Al addition. After increasing coagulant dosage from 12 to 120 mg/L, the total-Al in the treated water was controlled to below 0.2
mg/L. Purification systems with ozonation, chlorination, or potassium permanganate oxidation pretreatment units had little effects on
residual Al control; while UV radiation decreased Al concentration notably. Combined with ozonation, the effects of UV radiation were
enhanced. Optimal dosages were 0.5 mg O3/mg C and 3 hr for raw water with 15 mg/L of humic acid. Under UV light radiation, the
combined forces or bonds that existed among humic acid molecules were destroyed; adsorption sites increased positively with radiation
time, which promoted adsorption of humic acid onto polymeric aluminum and Al(OH)3(s). This work provides a new solution for
humic acid coagulation and residual Al control for raw water with humic acid purification. 相似文献
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Recent drinking water regulations have lowered the disinfection by-product standards as well as added new disinfection by-products for regulation. Natural organic matter (NOM) plays a major role in the formation of undesirable organic by-products following disinfection/oxidation of drinking water. It is suspected that most precursors to disinfection by-products are humic, although nonhumic substances are also suspected of contributing to these by-products. Many of the disinfection by-products have adverse health effects in humans (i.e., carcinogenic or mutagenic effects). The primary chlorinated disinfection by-products of concern include trihalomethanes, haloacetic acids, and haloacetonitrile. Fluorescence spectroscopy was used to study humic and fulvic acids. The two fractions of humic substances, humic and fulvic acids, were characterized by a double-peak phenomena in an overlapping fluorescing region. Disinfection by-product formation potentials of humic and fulvic acids have been correlated with total organic carbon, UV absorbance at 254 nm, specific absorbance and fluorescence. River humic and fulvic acid was found to have the highest reactivity to disinfection by-product formation as compared to soil and peat humic and fulvic acid. Fluorescence spectroscopy has shown to be a rapid and predictive tool for disinfection by-products formation potential of humic and fulvic acids. 相似文献
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低硒环境中人群对不同形态硒的保留量及其效应的研究 总被引:3,自引:1,他引:3
研究了低硒生态环境中有明显早期大骨节病病变的人群服用富硒酵母,亚硒酸钠和肌肉注射硒代二乙酸后体内硒保留量的动态变化。分析了治疗效应与摄入三种形态的硒后硒在体内保留量的关系,并与对照组作了比较。讨论了不同形态硒的生物活性。研究结果是三种形态的硒对早期大骨节病病变均有非常显著的疗效,再一次证明低硒生态环境是大骨节病流行的基础。 相似文献
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针对我国再生水普遍存在的色度问题,以天津市某污水厂二级出水为研究对象,采用三维荧光光谱和GC/MS技术对其进行组成分析,结果表明:再生水中主要带色物质为富里酸与腐殖酸类物质,同时还存在偶氮二甲酸二乙酯、N,N-二甲基乙醇胺、苄醚、1,4-二甲基吡啶氯化物等导致再生水色度的带色有机物。在再生水的臭氧降解实验中,臭氧可有效降解再生水中的富里酸与腐植酸类物质,去除率分别达到96.5%、97.3%。臭氧对再生水的色度与CDOM(有色溶解有机物)的降解也表现出了良好的效果,2 min内去除率可分别达到93.1%、86.2%。并且在色度物质的臭氧降解过程中,臭氧的直接反应占据主导地位,而并非与·OH的间接反应。该结果对再生水臭氧氧化工艺的设计应用有现实的指导意义。 相似文献
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The crystal growth of hydroxyapatite (HAP) seeds in presence of the abnormal collagen secreted by the chondrocyte grown in media containing free radical sources or fulvic acid and the type II collagen (pig cartilage) damaged by · OH and fulvic acid(FA) from potable water in endemic region of Kaschin-Beck disease (KBD) was studied. The results showed that in the former case, the abnormal collagen rich in type I collagen promoted mineralization in contrast with the type n collagen. The oxidatively damaged type II collagen became less inhibitive or even promotive. In all cases, the reaction followed a second order kinetics. The powder X-diffraction analysis and SEM observation indicated that the damaged type II collagen lowers the crystalinity in the beginning and made the final crystal more agglomerated. All the results showed that the abnormal and the damaged cartilage matrix affected the bimineralization and was likely to have played an important role in the development of KBD. 相似文献
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以ESR谱仪为主要工具,配合大骨节病病因研究,进行了有关地区饮水中有机物,主要是腐殖酸的黄腐酸级分和粮食真菌——镰刀菌代谢产物性质的相似性比较研究.结果发现,病区粮食中自由基浓度高于非病区,而尖孢镰刀菌(Fusarium Oxysporum)浸染使玉米粉的自由基浓度增加.在氧化、还原、加热和改变酸碱度等处理过程中,菌粮自由基的ESR谱表现出和黄腐酸同样的变化规律.菌粮水提液经GDX-102树脂吸附后,其ESR谱和pH值的关系表明,镰刀菌代谢产物中的自由基集中于带有酸性基团的分子上.水提液的紫外及荧光光谱和黄腐酸具有一定的相似性,因而推论镰刀苗代谢产物的自由基与黄腐酸一样,都是半醌自由基.最后就这类自由基和大骨节病的关系进行了讨论. 相似文献