土法炼砷亟待制止──关于衡阳市乡镇砷污染的调查

自80年代初起，乡镇上法炼砷开始在我市兴起，至今已有50年的历史了，立法炼砷在我市部分县（市）屡禁不止，并先后形成了三次炼砷热（第一次是1988年．第二次是1990年．第三次是1993年至今），该行业已成为我市环境污染的一大公害。1995年10月份，我们再次组织有关人员对全市七公（市）乡镇上法炼砷情况进行了一队调查．调查范围是全市1989年有炼砷厂家的七个县（市）．其中区域污染状况以我市常宁、来阳两县（市）沿大义山脉一带为重点。一、土法炼砷现状截止1995年10月底止，我市乡镇炼砷情况与1989年相比．主要有以下几个变化：1、炼砷…     

活性污泥法处理含砷废水初探

文章概述了含砷废水的产生及其处理方法，重点介绍了国内外研究报道较少的活性污泥法，以引起人们对这一有效除砷方法的重视。通过总结活性污泥法除砷的研究进展，探讨了活性污泥除砷的机理和影响因素，并提出今后要从活性污泥法除砷的机理、除砷工艺、及含砷废渣处理三方面开展研究，以促进该方法的应用。     

准确测定水中砷应注意的问题

砷的化合物在自然界普遍存在且均有剧毒，在环境监测中，砷是常规化验项目之一。本文对砷的测定方法、样品的预处理、干扰物的排除等有关问题进行了探讨。     

科学家利用植物处理土壤中的砷

美国乔治亚大学的研究人员发明了一种从土壤中去除砷的方法。乔治亚州的科学家们称：砷污染是一个日益严峻的环境问题。科学家们表示：土壤中累积的砷大部分都固定在植物的根系中，这使得对其进行安全处置非常困难。如今，遗传学家Richard Meagher所领导的该研究小组发现了一种将砷从植物根系中转移到叶子中的方法。这对于清理数千个对人类健康构成严重威胁的砷污染场地是个很有效的工具。     

双波长K系数方程法同时测定水样中的砷和磷酸盐

双波长K系数方程法同时测定水样中的砷和磷酸盐，是指选定两个测定波长λ1、λ2，将磷酸盐、砷在λ2处的吸光度转化为λ1处的吸光度，列出一个二元一次方程组，解得磷酸盐、砷在λ1处的吸光度，进而求得水样中的磷酸盐、砷含量。     

土壤中砷的污染控制技术研究

土壤砷污染修复是世界性的难题,日益受到人们的密切关注。本文阐述了土壤砷污染的现状、危害及其来源,探讨土壤砷污染的传统物理化学和生物修复技术的研究现状及特点的同时,重点阐述了纳米材料修复技术,尤其是纳米铁技术,并对土壤砷污染修复研究方向进行了展望。     

成都地区蔬菜中重金属污染分析与评价

通过对成都地区的9种蔬菜152个样品的可食部分中重金属元素的分析研究，查明了蔬菜中重金属汞、砷、铅、锡的含量及分布特征。结果表明，锡和铅是成都地区蔬菜中的主要污染元素，在检测的蔬菜样品中，锡和铅的超标率分别为29．4％和22％，最高超标分别为5.60倍和2.86倍，汞和砷无超标现象。     

砷污染稻作区发展旱稻控制稻米砷暴露风险探讨

农田砷污染是我国中南、西南稻作区面临的重要环境问题之一。水稻淹水种植条件下,土壤砷的溶解度较高,其移动性和生物有效性较大,水稻根系易吸收并向地上部转移砷。而在非淹水富氧条件下,土壤砷的移动性、生物有效性及稻米砷累积量显著降低。本文在综述水分管理影响水稻砷吸收基础上,提出：砷污染稻作区可通过水改旱、发展旱稻种植,显著降低土壤砷的生物有效性;在非淹水种植、降低土壤砷活性基础上,可通过筛选砷低吸收基因型旱稻,进一步控制水稻砷吸收和稻米砷累积,实现砷污染稻作区农产品质量安全保障与水危机缓解的双赢。目前,关于旱稻对砷的胁迫响应及对砷的吸收、转运与代谢研究鲜见报道,无疑,相关工作值得深入开展。     

土壤-植物系统中磷和砷相互作用关系的研究进展

砷元素导致的环境污染问题日益突出,施磷已成为植物修复砷污染土壤过程中必要强化措施之一。土壤-植物系统中磷和砷的相互作用关系是非常复杂的,研究表明：磷和砷在土壤中往往是共生的,但又存在竞争吸附关系;磷和砷在不同植物中的相互作用关系主要有拮抗效应和协同效应;有必要通过分子生物学手段对磷和砷表达基理进行深入研究,获得对砷具有超积累能力的植株。     

煤中砷及燃煤固砷技术研究

对煤中砷的含量、分布、赋存状态等地球化学特征进行了综述,分析了煤炭燃烧过程中砷的迁移转化行为与释放特性,指出煤中砷的燃烧释放不仅与砷的物理化学性质有关,更取决于煤中的浓度、赋存状态及燃烧工况等因素。进一步讨论了天然钙基材料燃煤固砷技术及燃煤砷污染控制的研究现状。     

Concentrations of additive arsenic in Beijing pig feeds and the residues in pig manure

The swine industry in China has grown rapidly over last two decades. Great amount of pig manure is generated in China, which can be used as organic fertilizers on agricultural lands. Meanwhile, the organic arsenic compounds have been used as feed additives for swine disease control and weight improvement. Once the excessive additives are released in the environment, arsenic may compromise food safety and environmental quality. There is a growing public concern about the arsenic residues accumulation in pig manure, however, little work has been done to investigate the exact arsenic content in pig feed and the residues in manure in China This study investigates the concentrations of arsenic in 29 pig feed samples and 29 manure samples collected from eight pig farms in the Chaoyang district, Beijing city. The detected rate of arsenic in 29 couples of samples was 100%. The concentrations of arsenic in pig feeds and manures ranged from 0.15 to 37.8 mg/kg and 0.42 to 119.0 mg/kg, respectively. The result showed that arsenic concentration in pig manure will be greatly elevated when the arsenic in pig feed was largely increased. The loading rates of pig manure in fourteen Beijing counties and districts were in the range of 2.7–57.2 t/ha yr. Accordingly, the potential soil arsenic increase rates resulting from land application of pig manure might range between 11.8 and 78.9 μg/kg yr. Despite these findings, it is too early to draw the conclusion that arsenic pollution from pig manure is serious in Beijing farmland; therefore, longitudinal studies about the chemical form transformation and the environmental behaviors of pig manure arsenic are required in order to come up with more definitive conclusions.     

对氨基苯胂酸的生命周期评价

本文介绍了最常用的有机胂制剂——对氨基苯胂酸的主要用途和污染特征，从生命周期的角度识别并定量评价了其生产、使用和残留过程的环境影响，评价结果表明对氨基苯胂酸在土壤中最终残留的环境骰响占其整个生命周期的99％以上，指出了常规环境影响评价在评价其环境污染上的局限性，据此提出逐步减少或禁止有机胂制剂的生产和使用、并在一些特殊的建设项目环境影响评价中推广生命周期评价的建议。     

Removal of arsenic from wastewater using iron compound: Comparing two different types of adsorbents in the context of LCA

A study was carried out in order to compare the environmental performance of two different types of adsorbents in removing arsenic (As) from wastewater. A FeCl₃-based adsorbent and a poly-Fe-based adsorbent were first synthesized and their abilities in adsorbing As from wastewater were investigated in terms of the adsorption density and the rate of adsorption. Here, it should be noted that the main material being used in the synthesis of the poly-Fe-based adsorbent was a waste product, known as polyferric sulfate or poly-Fe in short, which exits the manufacturing process of titanium dioxide.Both adsorbents were then compared in the context of life-cycle assessment (LCA). In other words, the experimental results (i.e. the value of the adsorption density and the rate of adsorption) were input into the LCA model in order to assess the environmental performance of each adsorbent in removing arsenic. An estimate for the environmental burden of each option was finally calculated as the sum of the depletion of abiotic resources (ADP), the global warming potential (GWP), the acidification potential (AP), the photo-oxidant formation potential (POCP), the eutrophication potential (EP), and the human toxicity potential (HTP). The main finding of this study was that the adsorption of arsenic by using the poly-Fe-based adsorbent is more attractive treatment option in the environmental protection point of view than the adsorption by using the FeCl₃-based adsorbent, which generates a relatively larger environmental burden.     

Removal of arsenic from wastewater using iron compound: Comparing two different types of adsorbents in the context of LCA

A study was carried out in order to compare the environmental performance of two different types of adsorbents in removing arsenic (As) from wastewater. A FeCl₃-based adsorbent and a poly-Fe-based adsorbent were first synthesized and their abilities in adsorbing As from wastewater were investigated in terms of the adsorption density and the rate of adsorption. Here, it should be noted that the main material being used in the synthesis of the poly-Fe-based adsorbent was a waste product, known as polyferric sulfate or poly-Fe in short, which exits the manufacturing process of titanium dioxide.Both adsorbents were then compared in the context of life-cycle assessment (LCA). In other words, the experimental results (i.e. the value of the adsorption density and the rate of adsorption) were input into the LCA model in order to assess the environmental performance of each adsorbent in removing arsenic. An estimate for the environmental burden of each option was finally calculated as the sum of the depletion of abiotic resources (ADP), the global warming potential (GWP), the acidification potential (AP), the photo-oxidant formation potential (POCP), the eutrophication potential (EP), and the human toxicity potential (HTP). The main finding of this study was that the adsorption of arsenic by using the poly-Fe-based adsorbent is more attractive treatment option in the environmental protection point of view than the adsorption by using the FeCl₃-based adsorbent, which generates a relatively larger environmental burden.     

北京市垃圾填埋场地下水中砷、汞含量分析

生活垃圾的处置一直以填埋为主,垃圾填埋承载着巨大的环境压力,尤其是垃圾填埋产生的渗滤液会对地下水造成砷、汞污染。为了解北京市生活垃圾填埋场地下水砷、汞污染水平,在北京市5座生活垃圾填埋场布设采样点,采集36个地下水样品,采用氢化物发生-原子荧光法,分析了地下水砷、汞含量特征。结果表明,36个地下水样品砷浓度范围0.41~4.82μg/L,汞浓度范围0.024~0.121μg/L,北京市典型垃圾填埋场地下水样品不存在砷、汞污染问题。     

On the potential of biological treatment for arsenic contaminated soils and groundwater

Bioremediation of arsenic contaminated soils and groundwater shows a great potential for future development due to its environmental compatibility and possible cost-effectiveness. It relies on microbial activity to remove, mobilize, and contain arsenic through sorption, biomethylation–demethylation, complexation, coprecipitation, and oxidation–reduction processes. This paper gives an evaluation on the feasibility of using biological methods for the remediation of arsenic contaminated soils and groundwater. Ex-situ bioleaching can effectively remove bulk arsenic from contaminated soils. Biostimulation such as addition of carbon sources and mineral nutrients can be applied to promote the leaching rate. Biosorption can be used either ex-situ or in-situ to remove arsenic from groundwater by sorption to biomass and/or coprecipitation with biogenic solids or sulfides. Introduction of proper biosorbents or microorganisms to produce active biosorbents in-situ is the key to the success of this method. Phytoremediation depends on arsenic-hyperaccumulating plants to remove arsenic from soils and shallow groundwater by translocating it into plant tissues. Engineering genetic strategies can be employed to increase the arsenic-hyperaccumulating capacity of the plants. Biovolatilization may be developed potentially as an ex-situ treatment technology. Further efforts are needed to focus on increasing the volatilization rate and the post-treatment of volatilization products.     

某区域内矿区土壤重金属污染与生态风险评价

探究区域内矿区土壤重金属变化并对其进行污染评价,旨在为该区域环境保护及污染治理提供一定的理论依据,以期实现矿山地质环境保护与矿产资源开发并行的矿业绿色发展。以铅、锌、镉、砷含量为评价指标,结合《土壤环境质量标准》(GB 15618—2018),采用重金属单因子污染指数法与内梅罗综合污染指数法进行重金属污染评价,并对该区域矿区潜在生态风险作出评定。结果表明,A矿区土壤各重金属含量的变异系数为149.05%~211.42%,B矿区土壤各重金属含量变异系数为60.88%~118.58%;A矿区土壤重金属均出现超标现象,其中铅、锌和镉含量超标较为严重,超标率在72%以上,而砷含量超标现象则相对较轻,超标率为36.36%;B矿区土壤铅和锌含量均未出现超标,超标率为0,而砷和镉含量则出现不同程度的超标,其中砷含量超标率为92.31%,镉含量超标率为65.38%;两个矿区土壤各重金属含量均超背景值的现象,超背景值比例为42.31%~100.00%。A矿区土壤以铅、锌和镉污染为主,而B矿区土壤中砷和镉的污染较为严重。两个矿区土壤重金属综合污染指数均属重度污染,A矿区生态风险综合指数为很强生态风险危害,而B矿区为中等生态风险危害。     

Potential anthropogenic mobilisation of mercury and arsenic from soils on mineralised rocks, Northland, New Zealand

Eroded roots of hot spring systems in Northland, New Zealand consist of mineralised rocks containing sulfide minerals. Marcasite and cinnabar are the dominant sulfides with subordinate pyrite. Deep weathering and leached soil formation has occurred in a warm temperate to subtropical climate with up to 3 m/year rainfall. Decomposition of the iron sulfides in natural and anthropogenic rock exposures yields acid rock drainage with pH typically between 2 and 4, and locally down to pH 1. Soils and weathered rocks developed on basement greywacke have negligible acid neutralisation capacity. Natural rainforest soils have pH between 4 and 5 on unmineralised greywacke, and pH is as low as 3.5 in soils on mineralised rocks. Roads with aggregate made from mineralised rocks have pH near 3, and quarries from which the rock was extracted can have pH down to 1. Mineralised rocks are enriched in arsenic and mercury, both of which are environmentally available as solid solution impurities in iron sulfides and phosphate minerals. Base metals (Cu, Pb, Zn) are present at low levels in soils, at or below typical basement rock background. Decomposition of the iron sulfides releases the solid solution arsenic and mercury into the acid rock drainage solutions. Phosphate minerals release their impurities only under strongly acid conditions (pH<1). Arsenic and mercury are adsorbed on to iron oxyhydroxides in soils, concentrated in the C horizon, with up to 4000 ppm arsenic and 100 ppm mercury. Waters emanating from acid rock drainage areas have arsenic and mercury below drinking water limits. Leaching experiments and theoretical predictions indicate that both arsenic and mercury are least mobile in acid soils, at pH of c. 3-4. This optimum pH range for fixation of arsenic and mercury on iron oxyhydroxides in soils is similar to natural pH at the field site of this study. However, neutralisation of acid soils developed on mineralised rocks is likely to decrease adsorption and enhance mobility of arsenic and mercury. Hence, development of farmland by clearing forest and adding agricultural lime may mobilise arsenic and mercury from underlying soils on mineralised rocks. In addition, arsenic and mercury release into runoff water will be enhanced where sediment is washed off mineralised road aggregate (pH 3) on to farm land (pH>6). The naturally acid forest soils, or even lower pH of natural acid rock drainage, are the most desirable environmental conditions to restrict dissolution of arsenic and mercury from soils. This approach is only valid where mineralised soils have low base metal concentrations.     

Arsenic accumulation in the hyperaccumulator Chinese brake and its utilization potential for phytoremediation

The unique property of arsenic hyperaccumulation by the newly discovered Chinese brake (Pteris vittata L.) fern is of great significance in the phytoremediation of arsenic-contaminated soils. The objectives of this study were to (i) examine arsenic accumulation characterized by its distribution pattern in Chinese brake, and (ii) assess the phytoextraction potential of the plant. Young ferns with five or six fronds were transferred to an arsenic-contaminated soil containing 98 mg As kg-1 and grown for 20 wk in a greenhouse. At harvest, the Chinese brake produced a total dry biomass of 18 g plant-1. Arsenic concentration in the fronds was 6000 mg kg-1 dry mass after 8 wk of transplanting, and it increased to 7230 mg kg-1 after 20 wk with a bioconcentration factor (ratio of plant arsenic concentration to water-soluble arsenic in soil) of 1450 and a translocation factor (ratio of arsenic concentration in shoot to that in root) of 24. The arsenic concentrations increased as the fronds aged, with the old fronds accumulating as much as 13,800 mg As kg-1. Most (approximately 90%) of the arsenic taken up by the Chinese brake was transported to the fronds, with the lowest arsenic concentrations in roots. About 26% of the initial soil arsenic was removed by the plant after 20 wk of transplanting. Our data suggest that the arsenic hyperaccumulating property of the Chinese brake could be exploited on a large scale to remediate arsenic contaminated soils.