贵州兴仁煤砷中毒患者的死因调查与防治

运用高分辨率等离子体质谱法(HRICP-MS)测定了贵州兴仁居民燃用煤中砷含量,并调查了煤砷中毒死者详细资料。结果显示,当地居民燃用煤中砷仍然高度富集,从1976年到2003年,贵州兴仁砷中毒患者共死亡265人,其中死于癌症人数最多,死于肝硬化、腹水的病人其次,其中大部分患者死亡时间集中在1992年以后,说明贵州兴仁煤砷中毒的远期危害逐渐暴露,煤砷中毒的预防与防治应从各个方面全面进行。     

砷中毒对免疫功能的影响

砷是环境中常见的污染物之一,地方性砷中毒是一种严重危害人体健康的慢性全身性疾病。就近年来有关砷中毒免疫损伤的研究资料,从免疫器官、细胞免疫、体液免疫、单核巨噬细胞系统整体功能以及基因表达等五个方面进行了综述,旨在说明砷中毒对机体免疫系统造成的影响。     

评《地方性砷中毒与乌脚病》

由新疆科技卫生出版社出版的（地方性砷中毒与乌脚病）一书最近和读者见面了。砷对人类健康的危害由来已久，至少可追溯到两千年以前。作为毒物的“砒”是自古以来人们所熟知的“毒工”。但对于自然环境因素所致的地方性砷中毒则只是近数十年才引起人们关注的地方性疾病。特别是近20年，随着我国新疆确认由饮水引起的地方性砷中毒以来，我国和世界一些国家和地区相继发现病区。地方性砷中毒逐渐成为引人注目的公共卫生问题。我国卫生部lop年将此病列为重点防治的地方病之一，要求各省区开展调查研究。但由于人们对此种地方病认识时间较短，…     

氢化物发生-原子荧光法测定水样中砷的注意事项

砷(As)是人们熟知的高毒性物质,砷的中毒机理被认为是其封锁了蛋白质的氢硫基或置换了酶活性中心的铜或锌[1].砷中毒可引起黑脚病,严重的可以导致癌症.     

煤中砷赋存状态与其脱洗率的关系

煤中砷是环境危害敏感有害微量元素之一，美国在1990年通过的清洁空气法修正案，对包含砷在内的11种微量元素表示关切。Swaine也把煤中砷列为对人类明显有害的元素之一。由于燃煤，砷曾经引起过诸多环境问题，在这些问题中尤以捷克和我国因燃用高砷煤所引发的环境问题最为突出。在捷克某使用高砷煤的发电厂下行风向的蜜蜂大量死亡，而我国则在贵州西南出现了大批的砷中毒患。     

负载型V2O5-WO3/TiO2催化剂的砷中毒研究

在实验室模拟了负载型V₂O₅-WO₃/TiO₂催化剂砷的中毒。采用催化剂活性测试,NH₃-TPD、H₂-TPR、XPS技术表征催化剂中毒特性。实验表明,砷中毒使催化剂活性降低明显。NH₃-TPD、H₂-TPR、XPS表征结果表明,As中毒使催化剂表面酸性降低,催化剂中W、Ti化学形态不受砷中毒的影响,而砷中毒改变了催化剂表面钒的化学形态,认为酸性降低和钒化学形态的改变引起了催化剂的中毒。     

燃煤烟气中砷对V_2O_5-WO_3/TiO_2 SCR脱硝催化剂性能的影响

通过将商业V_2O_5-WO_3/TiO_2脱硝催化剂暴露于含As_2O_3烟气中,制备了砷中毒催化剂,并运用X射线衍射(XRD)、比表面积(BET)、NH3化学吸附、傅里叶变换红外光谱(FT-IR)、X射线光电子能谱等技术表征分析了砷对催化剂性能的影响,并提出了催化剂砷中毒机理。结果表明,砷对催化剂具有严重的毒害作用,As_2O_3会吸附在催化剂表面,并被催化剂氧化形成As_2O_5覆盖层,减小催化剂比表面积,减少催化剂V活性位,阻止催化剂对NH3的吸附,造成催化剂失活。     

原子荧光光谱法测定尿中痕量砷

砷在自然界中对环境的污染较为普遍，砷中毒对人体健康危害很大，会影响细胞正常代谢，引发神经系统病变，含量高时可致人死亡，故对人体尿液中砷的测定很重要。测定痕量砷常用的方法为光度法，此方法测定时间长，手续繁杂，分析结果的重现性不是很好，本试验采用氢化物一原子荧光法，试样经消化后，在酸性条件下，加硫脲一抗坏血酸进行预还原，再用硼氢化钾将砷还原为AsH3，由载气导人石英炉原子化器进行原子化，在砷高强度空心     

通过皮肤吸收的砷中毒病例观察

测定了７０例皮肤接触砷（Ａｓ）引起中毒症状的患者血清砷、谷丙转氨酶（ＡＬＴ）、白细胞总数（ＷＢＣ）及分类（ＤＣ）计数，结果显示患者除出现严重皮肤溃烂的临床症状外，血中嗜中性粒细胞明显增高，均值高于正常对照组，Ｐ〈０．０１；血清砷含量均值为０．４２μｍｏｌ／Ｌ，显著高于正常对照组（ｘ↑－〈０．０１μｍｏｌ／Ｌ），Ｐ〈０．０１。说明人体皮肤对砷有很强的吸收能力，应尽量防止皮肤接触引起的类似中毒事件发生     

电化学氢化物发生-原子荧光光谱法测定尿中砷的含量

正砷及其化合物广泛存在于土壤、水、空气、植物及动物等环境中,都有可能被人体吸收,从而引起砷中毒,砷含量高时有可能致人死亡,故对人体尿砷含量的检测有重要意义。目前,测定砷含量的方法有分光光度法[1]、氢化物发生-原子吸收光谱法[2]、原子荧光光谱法[3-4]、电感耦合等离子体原子发射光谱法[5]和电感耦合等离子体质谱法[6]等,其中,氢化物发生原子荧光光谱法具有仪器便宜,样品前处理简     

微量元素砷与人体健康

讨论了砷在人体中的代谢，砷对人和动物的毒性影响，砷的生物学作用以及砷与癌症的关系。指出砷的毒性不仅取决于总量，更重要的是取决于化学形态；提示微量元素的形态与人体健康的关系应该作为从分子水平准确认识中草药中微量元素与中草药的药理生理活性关系的新思路；提出元素的生物活性与其存在状态的关系是药物拮抗作用和食物拮抗作用的实质。     

土壤中的砷在菠菜中的富集规律研究

通过盆栽试验研究了不同污染条件下菠菜对As的吸收富集规律。结果表明,菠菜叶片中As含量与土壤污染指数之间呈指数相关,相关性达到了极显著水平；而菠菜根中As含量与土壤As含量之间为线性相关。从结果中还可见,在盆栽条件下,土壤中As含量达到60mg·kg~(-1)时,菠菜中As含量才有可能超过食品卫生限量标准。这个土壤含量值比现行的国家标准高了2倍。由于蔬菜中的As限量卫生标准是根据每人每日允许摄入量(ADI)来确定的,而土壤中的限量标准则是根据土壤背景值调查资料统计得到的,因此在评价土壤环境以及蔬菜的安全质量时,会出现污染的土壤上生产出合格蔬菜的尴尬情况,说明两者之间的联系还需进一步研究。     

金属有机框架材料UTSA-74高效去除水溶液中的砷

利用水热法合成金属有机框架材料UTSA-74,并用它同时去除水中的As(Ⅴ)和As(Ⅲ)。 批次实验结果表明,在低质量浓度情况下(~1 mg/L),UTSA-74对As(Ⅴ)的去除率高达95%。 对As(Ⅲ)的去除率达85%。 经拟合,本实验符合拟二级动力学及Freundlich等温吸附模型。 本文还探究了共存离子(如Cl^-、NO₃^-、PO₄^3-)干扰影响,结果表明PO₄^3-的存在会抑制吸附的进行,可能是由于竞争吸附位点所致。 此外,本文对吸附后的材料进行洗脱(0.1 mol/L NaOH),将洗脱后的UTSA-74材料再次进行吸附探究,反复3次,其去除率仍可达70%左右。 为探究其中机理,本文通过X射线衍射(XRD)、扫描电子显微镜(SEM)、红外光谱(IR)对吸附前后材料进行表征,结果表明吸附过程中可能形成了Zn—O—As,以此促进吸附反应的进行。 综上所述,UTSA-74可以作为一种处理砷的新型吸附剂,具有一定的实用价值。     

高效液相色谱-等离子质谱联用分析食品中的主要有机砷和无机砷

 应用液相色谱-等离子质谱联用的方法分析食品样品中的主要有机砷(一甲基砷和二甲基砷)和无机砷(三价砷和五价砷)。 采用50%(体积分数)甲醇水溶液作为萃取剂,将食品样品进行预处理,再以5 mmol/L四丁氢铵,2 mmol/L丙二酸和5%(体积分数)甲醇水溶液作为流动相(pH 5.9),C18色谱柱(150 mm×4 mm i.d., 5 μm)将样品萃取液进行液相色谱分离,最后进入等离子质谱仪定性分析。 经测定发现,新鲜蔬菜和水果样品中主要含有的无机砷为三价砷和五价砷,有机砷为二甲基砷。一甲基砷在个别样品     

植物样品中痕量砷的形态分析研究进展

介绍了近十年来国内外植物样品中包括药用植物中砷的形态分析研究进展。由于植物中的砷含量甚低,其主要的检测手段是:氢化物电感耦合等离子体原子吸收光谱法(HG-ICP-AAS)、高效液相色谱-等离子体质谱法(HPLC-ICP-MS)、氢化物原子荧光光谱法(HG-AFS)。     

Determination of Arsenic in Algae – Results of an Interlaboratory Trial: Determination of Arsenic Species in the Water-Soluble Fraction

Seven algae samples, five purchased from food stores and two reference algae (BCR 279 Sea Lettuce) were distributed as blind samples to 13 laboratories from which five labs attempted a full characterisation of the water-soluble fraction with respect to their arsenic species. The extraction efficiency is largely dependant on the algae and varied from 3% to 96%. Besides inorganic arsenic (mainly as As^(V)) DMA^(V) and, in particular, several arsenosugars were identified in all samples. From the five labs, three labs gave agreeable results in respect of the arsenic species identification and its quantification, although different chromatographic methods were used. Different Hijiki samples seem to contain largely different arsenic concentration (67–113 mg As/kg) which may also have an influence on the distribution of inorganic arsenic and arsenosugars.     

Distribution of Arsenic Species in Different Leaf Fractions – An Evaluation of the Biochemical Deposition of Arsenic in Plant Cells

This paper describes an approach to the determination of arsenic species bonding with proteins or low-molecular peptides by separation of leaf proteins and protein precursors into three fractions and analysis of arsenic species associated to these fractions. Plants irrigated with arsenite contained not only arsenite but also arsenate and dimethylarsinate. In plants treated with arsenate, the major component was arsenite in the water-soluble fraction containing soluble protein and non-protein (F II) and in the acid-soluble non-protein fraction (F IV). Concentrations of 43 mg kg⁻¹ (As(V)-treatment) and 18 mg kg⁻¹ (As(III)-treatment) could be analyzed in the water-insoluble structure protein fraction F I (56 ± 15% of the total mass). Based on the concentration of arsenic species in all fractions, conclusions are drawn over the fixation of arsenic in the fraction of insoluble structure proteins, in the fraction of soluble cytosolic proteins as well as the fraction of amino acids.     

Arsenic bioaccumulation and species in marine polychaeta

Published whole tissue arsenic concentrations in polychaete species tissues range from 1.5–2739 µg arsenic/g dry mass. Higher mean total arsenic concentrations are found in deposit‐feeding polychaetes relative to non‐deposit‐feeding polychaete species collected from the same locations. However, mean arsenic concentrations at some of the locations are skewed by the high arsenic concentrations of Tharyx marioni. There appears to be no direct correlation between sediment arsenic concentrations and polychaete arsenic concentrations. Arsenic bioaccumulation by polychaetes appears to be more controlled by the physiology of the polychaetes rather than exposure to arsenic via ingested material or the prevailing physiochemical conditions. Arsenic concentrations in polychaete tissues can vary greatly. Most polychaete species contain the majority of their arsenic as arsenobetaine (57–98%), with trace concentrations of inorganic arsenic (<1%) and other simple methylated species (<7.5%). However, this is not always the case, with unusually high proportions of arsenite (57%), arsenate (23%) and dimethylarsinic acid (83–87%) in some polychaete species. Arsenobetaine is probably accumulated by polychaetes via organic food sources within the sediment. The presence of relatively high proportions of phosphate arsenoriboside (up to 12%) in some opportunistic omnivorous Nereididae polychaete species may be due to ingestion of macroalgae, benthic diatoms and/or phytoplankton. Consideration of the ecology of individual polychaete species in terms of their habitat type, food preferences, physiology and exposure to arsenic species is needed for the assessment of arsenic uptake pathways and bioaccumulation of arsenic. Future research should collect a range of polychaete species from a wide variety of uncontaminated marine habitats to determine the influence of these ecological factors on total arsenic concentrations and species proportions. Copyright © 2005 John Wiley & Sons, Ltd.     

微波王水消解不赶酸原子荧光光谱法测定土壤中的砷

采用微波消解土壤样品不赶酸的情况下利用原子荧光光谱法测定土壤中的砷.结果表明:微波王水消解土壤样品不赶酸情况下,砷的测定值均在国家标准物质ESS-1的推荐值范围内.砷的线性范围分别为0.0 ～50.0μg/L,相关系数为r=0.9995.按称取0.2g样品,定容至50 mL,求出砷检出限为0.5 mg/kg.砷回收率为...     

Experimental Design Optimization of Arsenic Speciation in Groundwater

The optimization of a Differential-Pulse Stripping Voltammetry (DPSV) procedure for arsenic speciation determination, using sodium diethyldithiocarbamate (DDTC-Na) as complexing agent, is described. An experimental design methodology was used to select the optimal experimental conditions. A robust regression method was used for the calibrations under these conditions that eliminate anomalous points. Electroinactive As(V) was reduced to As(III) with sodium thiosulfate prior to determination. The detection limit obtained was 1.95 × 10^?9 mol dm^?3. This procedure was successfully applied to the determination of arsenic speciation in groundwater.