Feasibility Evaluation of Using Biochar-based Permeable Reactive Barrier for the Remediation of Mercury and Arsenic Composite Polluted Water Bodies

This study employed a modified biochar material to construct a permeable reactive barrier(PRB)for the treatment of water bodies polluted with mercury and arsenic.The experimental results demonstrated that the addition of goethite-modified biochar significantly enhanced the remediation efficiency of As(III),achieving a maximum removal rate of 100%.Conversely,pure biochar exhibited high efficiency in the removal of Hg(II),with a maximum removal rate approaching 100%.Furthermore,the pH level of the water significantly influenced the adsorption efficiency of heavy metal ions,with the optimal removal performance observed at a pH of 6.0.The PRB system demonstrated excellent removal rates under low concentrations of heavy metals.However,as the concentration increased,the remediation efficiency exhibited a slight decrease.In summary,the findings of this study provide compelling evidence for the use of modified biochar in the construction of PRBs for the remediation of mercury and arsenic-polluted water bodies.Furthermore,the study reveals the mechanism by which pH and heavy metal concentration influence remediation efficiency.

Determination of Arsenic and Mercury in Soil by Microwave Digestion and Hidride GenerationAtomic Fluorescence Spectrometry

[Objective] The aim was to develop a rapid, simple method for determina- tion of arsenic and mercury in soil samples by atomic fluorescence spectrometry. [Method] The method for determination of As and Hg in soil by combined atomic fluorescence spectrometry and microwave digestion was used. [Result] The concentration curve was linear within the range of 0-80.0μg/L of As and 0-8.0 μg/L of Hg, and the detection limits of As and Hg was 0.036 μg/L and 0.015 μg/L, respectively. The precision for elevenfold determination of As at 40.0 ug/L level and Hg at 4.0μg/L level were 1.1% and 2.2%（RSD）, respectively. Recoveries of 103.0%-106.6% for As and 90.0%-95.0% for Hg were obtained for there soil samples. [Conclusion] The proposed method has the advantages of simple operation, high sensitivity, and high efficiency; it was successfully used for determination of As and Hg in soil samples.

Determination and ecological risk assessment of arsenic and mercury in sediments from the Changjiang River Estuary and adjacent East China Sea

Arsenic(As)and mercury(Hg)are pollutants presented in marine environment.A process of atomic fluorescence spectrometry was proposed for the simultaneous determination of As and Hg in marine sediment samples(n=38)collected from the Changjiang River Estuary and adjacent East China Sea.The proposed method used an optimized pretreatment procedure in an aqua regia–H_(2)O digestion system.Recoveries of As and Hg increased to97%and 98%,respectively,with suitable precisions(2.7%–4.1%)under optimized process conditions.As and Hg were widely presented in these samples,with the ranges of content values were 2.39–8.77μg/g for As and48.03–410.8 ng/g for Hg.Results indicate that anthropogenic factors strongly influence the abundances of As and Hg in investigated samples.The preliminary environmental risk assessment was investigated using the Igeoaccumulation index(Igeo)and anthropogenic contribution rate(M).Findings reveal that Hg demonstrates a strong ecological risk(with average values of 1.3 and 72%for Igeo and M,respectively)in the sediments from the Changjiang River Estuary and adjacent East China Sea.Therefore,Hg should be considered in future investigations.

Health Risk Assessment in Children by Arsenic and Mercury Pollution of Groundwater in a Mining Area in Sonora, Mexico

A highly acidic spill from one of the most important copper mines in the Americas (Buenavista del Cobre) occurred in Sonora, Mexico in August, 2014. 40,000 m3 of metals-enriched sulphate solution escaped into the Sonora River representing the worst ecological disaster in Mexican history. The spill affected the economy, water accessibility and the health of residents near the river. Despite the economic importance of mining in this area, no environmental assessment was undertaken. There is no information about the health impact of this event on the local population. The study assesses the health risk among children exposed to arsenic and mercury via groundwater in five communities located in a mining area into the Sonora River Basin, Mexico. Local drinking water from the localities was sampled one year after the spill and it was analyzed for arsenic and mercury by Atomic Absorption Spectrometry coupled with Hydride Generation (AAS/HG). Further, some of the traditional local foods were sampled and analyzed for the same elements. Results indicate that levels of arsenic in drinking water did not exceed the Mexican Norm (25 μg As/L) or the EPA Guideline (10 μg As/L). The concentrations of mercury exceeded the WHO and Mexican Legislation value (1.0 μg Hg/L). The Hazard Quotient (HQ) values for arsenic were >1 in 42% of children exposed and for mercury in 67% of the children. Foods concentrations contained in the ranges of 9.2 to 62.0 μg As/Kg and 0.28 to 42 μg Hg/Kg for arsenic and mercury respectively. These values are below the Codex Alimentarius limits. Children affected by mining activities are at risk of developing chronic diseases associated with low arsenic and mercury exposure via groundwater consumption, without consideration of the contribution from these metals by other important exposures routes.

Spatial and Temporal Patterns of Variation in Environmental Quality of Water and Sediments of Streams in Mined and Unmined Areas with Emphasis on Mercury (Hg) and Arsenic (As)

Heavy metal pollution from both anthropogenic and natural processes can have significant effect on environmental quality of stream and river systems. However, in Ghana, heavy metal pollution of waterbodies is attributed mainly to mining activities but the role of natural mechanisms in altering stream water and sediment quality in relation to heavy metals has received little attention. Spatial and temporal variation in water quality parameters and heavy metal concentrations in water and sediments were studied comparatively in a river and two streams in a gold-rich watershed impacted by heavy mining activities. Samples were collected monthly over a twelve-month period from November 2010 to October 2011 from upstream (unmined) and downstream (mined) sections of the studied streams. Parameters measured include temperature, dissolved oxygen, conductivity, pH, turbidity, colour, mercury (Hg) and arsenic. High spatial variability of water quality parameters was found. Hg concentrations in water were extremely low in both upstream and downstream areas. Maximum geochemical background levels of Hg in unmined pristine areas were 2.45 mg/g whilst arsenic was 29.10 mg/g. By contrast, gold-mined downstream areas recorded Hg and arsenic concentrations of 8.75 mg/g and 82.53 mg/g in stream sediments respectively. Levels of Hg and arsenic in sediments were several orders of magnitude greater than concentrations in surface water in downstream sections and this may be explained by substances originating from mining activities, upstream transport or remobilized sedimented materials in the overlying water column. Our study showed that both natural and human activities may contribute to heavy metal pollution in the highly mineralized watershed of the Pra River Basin. Human factors are however likely to amplify the natural background levels of heavy metals.

A Pilot Survey of Mercury in Drugs, Cosmetics and Household Products Using Reliable Analytical Methods

The concentration of mercury (Hg) was accurately determined in more than 228 drugs, cosmetics and household products manufactured in a variety of countries. Some drugs were found to contain up to 4424 ppb Hg, and some skin creams contained up to 2769 ppm Hg. Hg in skin creams was found to be almost 100% elemental Hg (Hg0), a volatile species of Hg. Hg0 can enter the human body through inhalation and skin absorption, potentially resulting in the serious consequence of mercury poisoning. The mercury can also volatilize, contaminating the surrounding air. Other people, for example, infants and children, who are close to or contacting the skin of the person using the cosmetics, can also absorb the mercury. Total mercury (THg) was determined by combustion/trap/CVAFS. Methyl mercury (MeHg) and inorganic mercury (Hg2+) were determined by the ethylation based method. The emission of Hg0 was determined by evaporation/trap/CVAFS. All analyses were performed in accordance with explicit quality assurance and quality control protocols and procedures.

A Review of the Potential Issues of Pollution Caused by the Mineral Elements, Mercury, Lead and Arsenic, Its Possible Impacts on the Human Beings and the Suggested Solutions

Objective: This paper mainly discusses and summarises the potential issues of pollution caused by the Mineral elements, Mercury, Lead and Arsenic, its possible impacts on the human beings and the suggested solutions. Methods: This paper is prepared by reviewing the latest academic literatures. Result: First, this article discusses two aspects including the effects of Mercury, Lead and Arsenic on the Chinese herbal medicine and the potential issues of causing the environmental pollution. And then further study its toxicity effects and the side impacts on the human bodies in order to realize the actual circumstances people are encountering nowadays. This paper will also the corresponding its treatment method of reviews. Hope this will provide a valuable reference. Conclusion: Theses issues caused by the Mineral elements are prominent nowadays, thus the ongoing researches on the impacts of pollution and the possible solutions are regarded as highly valued in order to conserve the natural environment and meanwhile safeguard the well beings of people and the future offspring.

江西省市售不同类别代用茶中水分含量及重金属污染状况分析

目的了解江西省市售花类、叶类、根茎类和果(实)类代用茶中水分含量及铅、砷、镉、汞等重金属污染状况。方法在江西省全省范围内采集250份代用茶,对每份样品进行水分、铅、总砷、镉和汞的检验,按照GH/T 1091—2014《代用茶》判定是否合格。结果代用茶的水分超标率为38.8%,其中主要为叶类代用茶(占16.8%);各类别代用茶中果(实)类中的水分含量最高,中位数为13.2%。250份样品的重金属元素中汞的检出率最低(55.2%),铅均合格(<5.0 mg/kg),镉和总砷的超标率分别为11.6%和3.6%。不同类别代用茶中铅、总砷、镉和汞的检测结果差异均有统计学意义(P<0.05)。结论叶类和果(实)类代用茶的水分相比其他类别代用茶易超标,叶类代用茶中铅和总砷污染水平较高,而花类和根茎类代用茶中的镉污染水平较高。在今后制定统一的食品安全标准限度方面中应重点关注。

水浴消解-原子荧光法测定糖厂滤泥中的总砷和总汞

建立了采用水浴消解-原子荧光光度法测定糖厂滤泥中总砷和总汞含量的方法。试验结果表明,在最佳测试条件下,糖厂滤泥样品中总砷、总汞的线性浓度范围分别为0~100μg/L、0~2.00μg/L;总砷、总汞的检出限分别为0.012 mg/kg、0.001 mg/kg;精密度试验(n=9)总砷、总汞的相对标准偏差(RSD)分别为2.4%、3.8%;回收试验总砷、总汞的回收率分别为98.8%~107.9%、98.5%~107.2%。该方法准确度高,其精密度、检出限、回收率均能满足检测的要求,可为广西糖厂滤泥中总砷和总汞的含量测定及安全性评价提供参考。

地下水中砷和汞的不同测试方法

本文研究了原子荧光法(AFS)、电感耦合等离子体质谱法(ICP-MS)和电感耦合等离子体发射光谱法(ICP-OES)等3种不同方法检测地下水中的砷和汞.结果表明,地下水中砷汞的3种测试方法在一定的浓度范围内标准曲线线性良好,相关系数均在0.999以上,加标回收率和精密度较好,质控测定结果均在理论值范围内,说明3种方法有很好的准确性和稳定性,分析数据结果可靠. AFS和ICPMS砷检出限分别为0.10μg·L^(-1)和0.02μg·L^(-1),汞检出限分别为0.03μg·L^(-1)和0.05μg·L^(-1),都远低于相关水质标准检出限以及《地下水质量标准》规定的Ⅰ类水限值,完全能够满足地下水测试要求.而ICPOES砷和汞的检出限分别为20μg·L^(-1)和9.36μg·L^(-1),可用于受到污染的地下水样品检测.

光谱法测定农产品中铅镉铬汞砷的一次性消解方法

为了缩减检测用时与降低综合成本,对农产品中铅、镉、铬、汞、砷的检测方法进行改进,对检测条件进行优化和协调试验,探索一次性消解定容同时检测5种重金属元素的可行性。通过理论分析和试验研究,参考国标方法和成熟文献上的方法,消解用酸中加入盐酸和高氯酸,消解前120℃预消解30 min,消解赶酸后加入20 g/L硫脲+50 g/L抗坏血酸溶液转移定容,铅、镉检测加入磷酸二氢铵基体改进剂,砷、汞同时检测。通过条件取舍与优化,达到使用原子吸收(AAS)和原子荧光(AFS)同时检测的目的。检测标准物质和标准溶液,测定值均在其1倍不确定度范围内,准确度良好,相对标准偏差均小于20%,精密度良好。改进方法检测结果较准确,操作简便,适用于利用AAS和AFS对农产品中铅、镉、铬、汞、砷的测定。

食用菌中砷、汞富集特征与吸收机制研究进展

食用菌包括人工菌和野生菌,极易从土壤中吸收并富集重(类)金属。汞(Hg)、砷(As)是土壤中典型高毒性重(类)金属元素,易被食用菌吸收,并通过食物链传递、富集,最终进入人体,具有潜在食品安全风险。食用菌(特别是野生菌)中As、Hg富集特征及潜在风险已引起广泛关注,但目前关于食用菌As、Hg污染特征及其吸收机制的系统性综述较少。据此,本文对食用菌(人工菌和野生菌)中As、Hg含量与分布特征(菌盖、菌柄)进行综述,重点阐述食用菌对As、Hg的富集能力、转运能力及吸收方式(细胞表面被动吸附、细胞内主动吸收),可为对比分析人工菌和野生菌对As、Hg吸收、富集、分配差异提供基础信息,并为深入研究食用菌吸收富集重金属的过程机制提供理论依据,对食用菌重金属风险阻控和保障食用菌食品安全具有一定的现实意义。

水浴密封消解-原子荧光法测定土壤中的汞和砷

建立水浴密封消解-原子荧光法测定土壤中的汞和砷。采用一次性聚丙烯离心管、恒温水浴振荡器为消解设备,取样质量为0.3~0.5 g,以5 mL王水溶液(1∶1)为消解液,消解时间为1 h。汞、砷的质量浓度分别在0~2、0~20μg/L范围内与荧光强度线性关系良好,相关系数分别为0.999 7、0.999 8,汞和砷的检出限分别为0.001、0.01 mg/kg,定量限分别为0.004、0.04 mg/kg。采用该方法对土壤成分分析标准物质GSS-8、GSS-23、GSS-29进行测定,汞和砷测定结果的相对标准偏差分别为3.5%~6.6%、1.8%~3.8%(n=6),相对误差分别为-3.3%~4.9%、-2.1%~2.5%。汞和砷的回收率分别为93.7%~104%、98.6%~102%。该方法采用一次性聚丙烯离心管,无需消清洗解管,消解过程简单,消解液用量少,适用于大批量土壤样品测定。

微波消解-电感耦合等离子体质谱法测定土壤中砷和汞

试验采用微波消解-电感耦合等离子体质谱法(ICP-MS)测定工业园区土壤中砷和汞。土壤样品采用微波消解,消解酸体系中,浓硝酸、氢氟酸和高氯酸的体积比为2∶1∶1,消解时间为35 min,消解温度为180℃。结果表明,砷浓度介于0.1~50.0μg/L时,线性关系良好,相关系数为0.999 6(大于0.995),加标回收率为103.2%,相对标准偏差(RSD)为2.33%,检出限为0.056μg/L;汞浓度介于0.1~15.0μg/L时,线性关系良好,相关系数为0.998 4(大于0.995),加标回收率为99.2%,RSD为1.84%,检出限为0.009μg/L。该方法重复性好,精密度高,适用于工业园区土壤中微量元素残留的检测。

塞曼效应电热原子吸收光谱法测定化妆品中总汞含量

建立塞曼效应电热原子吸收光谱法检测化妆品中总汞含量的方法。结果显示,在膏霜类、乳液类、粉类、蜡基类化妆品方法的检出限(LOD)为0.4 ng/g,定量限(LOQ)为1.2 ng/g,液态类化妆品方法的LOD为0.1 ng/mL,LOQ为0.3 ng/mL。在低、中、高不同加标水平时,相关系数均大于0.999,线性关系良好,加标回收率为91.7%~109.7%,相对标准偏差为0.7%~4.4%(n=6),质控样测定结果均在标准值范围之内。利用该方法对15批次不同基质化妆品中汞含量进行测定,并与原子荧光光度法、汞分析仪法测定结果进行比较,结果基本一致,且灵敏度更高。因此,该方法简便、快速,测定结果准确度可靠,灵敏度高且重现性好,适用于不同基质化妆品中总汞含量的测定。

离心管石墨消解-原子荧光光谱法测定土壤中总砷和总汞

对现有国标方法(GB/T 22105.1—2008《土壤质量总汞、总砷、总铅的测定原子荧光法第1部分:土壤中总汞的测定》和GB/T 22105.2—2008《土壤质量总汞、总砷、总铅的测定原子荧光法第2部分:土壤中总砷的测定》)测量土壤中总砷和总汞的方法进行改进,建立离心管石墨消解-原子荧光光谱法测定土壤中总砷和总汞含量。称取国家一级土壤标准物质GBW 07428、GBW 07408样品于离心管中,采用王水消解,测定土壤中总砷和总汞含量。砷和汞的质量浓度在一定范围内与荧光强度具有良好的线性关系,线性相关系数均大于0.999,检出限分别为0.057、0.0043 mg/kg。测定结果的相对标准偏差为2.48%~3.82%(n=8),砷、汞的加标回收率分别为94.0%~101.4%、98.6%~103.5%。该方法检出限、精密度、准确度均能满足土壤检测的要求,样品无需过滤或放置澄清,能更好地满足日渐增加的土壤分析工作。

门头沟区蔬菜中砷、汞的污染状况与健康风险评估

目的:了解门头沟区的蔬果类食品中砷、汞的含量水平与污染状况,评估膳食暴露的健康风险。方法:采集并检测市场在售的蔬菜样品,采用污染指数法评价样品的污染状况,靶向危害系数法评估健康风险。结果:共检测蔬菜样品210件,总砷中位值为0.016 0 mg·kg^(-1),总汞中位值为0.001 6 mg·kg^(-1)。合格率为100%。污染指数法评价结果显示,209件样品Pi<0.7,在安全范围内;1件蔬菜样品总汞Pi值为0.83,在警戒线内。综合污染指数Pn均小于0.7,表明样品安全、未受到污染。靶向危害系数THQ、TTHQ均小于1,表明样品不存在明显的健康风险。结论:门头沟区在售的蔬菜不存在明显的健康风险。

原子荧光光谱法测定小儿惊风七厘散中雄黄和朱砂的含量

通过采用微波消解法对小儿惊风七厘散中的总砷和总汞进行提取,模拟人体胃肠道环境,仿生提取可溶性砷和可溶性汞,利用原子荧光光谱法测定小儿惊风七厘散中总砷、总汞、可溶性砷和可溶性汞的含量。结果表明,砷(As)元素和汞(Hg)元素线性回归方程线性关系良好,精密度、回收率、稳定性实验RSD均小于2.0%,该方法测定速度快、灵敏度高、稳定性高,可用于中药制剂小儿惊风七厘散中As和Hg金属元素的含量测定。

土壤中砷汞样品同步消解测试和消解液保存条件探究

为提升大批量土壤样品砷汞分析测试时的效率,重点考察了砷汞土壤样品同步水浴消解后分别测试的准确度和精密度,同时考察了定容试剂、保存温度、保存时间对砷汞消解液测试结果的影响。经测定,2类不同类型砷汞土壤标准样品测试值均在质控范围内,6次测定的精密度在2.5%~7.4%。砷汞土壤标准样品经水浴消解后定容试剂为10%盐酸溶液,在5℃以下存放5 d时,其测定值仍在土壤标准样品质控范围内。研究表明,砷汞土壤标准样品经同步消解后分开测试满足质控要求,其消解液可在10%盐酸溶液的介质、5℃以下存放5 d,在大批量砷汞土壤样品分析时,有助于分析人员合理安排时间,统筹完成工作任务。

原子荧光光谱法检测食用鱼中汞、砷含量

目的:建立原子荧光光谱法同时测定食用鱼中汞、砷含量的方法。方法:采用微波消解法对样品进行预处理,原子荧光光谱法同时测定食用鱼(淡水鱼、海水鱼)中汞、砷含量,分析其检测结果。结果:汞在0~10.0μg·mL^(-1)时线性关系良好,砷在0~40.0μg·mL^(-1)时线性关系良好,相关系数> 0.999。汞的检出限在2.50~3.83μg·mL^(-1),回收率为94.1%~99.0%,精密度为2.9%;砷的检出限在2.30~3.68μg·mL^(-1),回收率为93.3%~99.2%,精密度为2.0%。对比发现食用海水鱼中汞、砷含量显著高于淡水鱼(P <0.05)。结论:原子荧光光谱法操作简单、检测灵敏度较高,可同时测定食用鱼汞、砷含量。