宁波市饮用水中重金属铁锌铜健康风险度评价

对宁波市区内36个样点的饮用水中Fe,Zn,Cu的质量浓度进行了调查研究,并应用目前美国环保局推荐的健康风险评价模型对各区饮用水中Fe,Zn,Cu所引起的健康风险度作了初步评价。结果表明,宁波市区Fe,Zn,Cu的平均质量浓度范围分别为Fe 35~809μg/L,Zn51~1 147μg/L,Cu 14~98μg/L;通过饮水途径所引起的非致癌健康风险中Zn在邱隘(样点)的致癌年风险最大(1.7×10-5),但低于国际辐射防护委员会(ICRP)推荐的通过饮水途径最大可接受年风险水平(5×10-5),Cu,Fe的年风险水平(10-8~10-9)均远低于ICRP推荐的最大可接受风险水平。因此与Fe,Cu相比,Zn为主要的风险污染物,应进行优先管理。     

高效液相色谱法测定间硝基苯磺酸还原制备间氨基苯磺酸过程中的间氨基苯磺酸和间硝基苯磺酸

提出了测定间硝基苯磺酸还原制备间氨基苯磺酸生产过程中间氨基苯磺酸和间硝基苯磺酸的高效液相色谱法。采用kromasil C_(18)色谱柱(150 mm×4.6 mm,5μm)分离,以0.10 mol·L~(-1)的磷酸二氢铵溶液为流动相,紫外检测波长为236 nm。间氨基苯磺酸和间硝基苯磺酸的线性范围分别为4.0×10~(-5)~2.4×10~(-4),8.0×10~(-5)~4.0×10~(-4)mol·L~(-1),检出限(3S/N)分别为1.5×10~(-6),3.5×10~(-6)mol·L~(-1),测定下限(10S/N)分别为5.0×10~(-6),1.0×10~(-5)mol·L~(-1)。加标回收率在95.3%~102%之间,测定值的相对标准偏差(n=6)在0.86%~2.6%之间。     

黔产市售绿茶重金属的含量特征及健康风险评估

为研究黔产市售绿茶中重金属的含量分布特征及健康风险,以五个生产加工地的黔产市售绿茶为研究对象,分析其9种重金属(Pb、Cr、Cd、Hg、Cu、Zn、Mn、Ni和As)含量,利用美国环境保护署(USEPA)推荐的健康风险评价模型进行人体重金属的健康风险评价。结果表明,五种茶叶中Cr、Cd、Pb、Hg、Cu和As含量均低于国家限量标准。黔产市售绿茶的重金属浸出率大小次序为Zn>Mn>Hg>As>Cd>Pb>Cr>Cu>Ni。健康风险评价结果表明,五个产地的绿茶中重金属通过饮茶途径所产生的健康危害个人年风险大小次序为Cd>As>Mn>Ni>Cr>Hg>Pb>Zn>Cu,茶叶中重金属通过饮茶途径所产生的个人健康危害年风险总和为4.33×10-6~5.73×10-6 a-1,均低于USEPA和ICRP推荐的最大可接受风险水平,表明重金属引起的健康危害极小,其对暴露人群造成的健康危害可忽略不计,绿茶中重金属均处于安全范围内。     

银铜双金属/组氨酸功能化石墨烯量子点/石墨烯杂化物的制备及其在电化学法测定黄瓜中毒死蜱、克百威和多菌灵上的应用北大核心CSCD

为了提高金属纳米粒子在石墨烯片上的分散度,通过组氨酸功能化石墨烯量子点(His-GQD)作为桥梁,设计合成银铜双金属/His-GQD/石墨烯杂化物(AgCu/His-GQD/G)。His-GQD通过π-π堆积作用固定到氧化石墨烯上,然后与银离子和铜离子结合形成复合物,最后在氮气保护下热还原获得AgCu/His-GQD/G。形成的杂化物表现出独特的三维结构,且银、铜纳米粒子均匀分散在石墨烯片上。基于该杂化物构建了电化学适配体传感器,适配体与杂化物上的银、铜纳米粒子通过Ag-N和Cu-N键连接而修饰到电极表面上,用于毒死蜱、克百威和多菌灵的测定,表现出高的灵敏度和选择性。毒死蜱、克百威和多菌灵标准曲线的线性范围分别为1.00×10^(-2)~1.00×10^(3)pmol·L^(-1)、1.00×10^(-1)~1.00×10^(4)pmol·L^(-1)和1.00~1.00×10^(6)pmol·L^(-1),检出限(3S/N)分别为3.2×10^(-3)pmol·L^(-1)、2.3×10^(-2)pmol·L^(-1)和2.9×10^(-1)pmol·L^(-1)。该适配体传感器用于黄瓜样品中克百威、毒死蜱和多菌灵的测定,仅检出多菌灵,检出量为1.21 pmol·L^(-1)和1.25 pmol·L^(-1);并按标准加入法进行回收试验,回收率为99.3%~100%。     

含铈重轨钢珠光体组织对抗大气腐蚀的影响

通过向重轨钢中添加Ce来改变重轨钢组织,研究其组织对抗大气腐蚀的影响。用中频感应炉冶炼实验用U71Mn,轧制后空冷。SEM测量了实验钢的珠光体片层距,在浓度为(1.0±0.05)×10~(-2)mol·L~(-1)的NaHSO3溶液中模拟了工业大气环境下实验钢的腐蚀,利用热力学计算、失重率、SEM、XRD和电化学方法研究了珠光体组织对抗大气腐蚀的影响。经过热力学计算,含Ce的U71Mn在1600～800℃析出的主要物相Ce_2O_2S,从而减少了MnS的析出,减少了钢中的有害夹杂析出。随着Ce加入量的增加,U71Mn钢珠光体片层间距先减小后增加,在40×10~(-6)时珠光体片层间距达到最小值0.2480μm。随着腐蚀周期的增加,失重量增加,在腐蚀的后期失重速率基本恒定,失重与时间呈线性关系,斜率分别为1.3755,1.0008,1.3396 g·(m~2·h)~(-1)。加入40×10~(-6)Ce和加入80×10~(-6)Ce相比与不含Ce的U71Mn钢耐腐蚀性能分别提升了12.50%和10.4%。电化学实验分别加入铈0,40×10~(-6),80×10~(-6)的三个样品在第五周期的电流分别为1.93×10~(-4),3.71×10~(-9),2.01×10~(-7)A。XRD物相半定量分析三组样品的稳定产物和不稳定产物的比值分别为0.670,1.625,1.110。对腐蚀样品的表面形貌进行分析,在腐蚀样品的表面均为花状γ-FeOOH,加入40×10~(-6)Ce的晶粒最大,不含Ce的U71Mn钢最小,加入80×10~(-6)Ce居中。     

宁波市饮用水中重金属污染物镉健康风险评价

对宁波市区内36个监测点的饮用水中Cd的质量浓度进行了调查研究,并应用目前美国环保局推荐的健康风险评价模型对各区饮用水中Cd所引起的健康风险度作了初步评价。结果表明,宁波市区镉的平均质量浓度范围为0～3.2μg/L;通过饮水途径所引起的致癌健康风险中Cd在邱隘的致癌风险最大(8.7×10-6.a-1),但低于国际辐射防护委员会(ICRP)推荐的通过饮水途径最大可接受风险水平(5×10-5.a-1)。由于邱隘地区饮用水中的镉风险度相对较高,因此应优先对其进行管理。总体来说,Cd的个人年风险在10-6水平,所以宁波市通过饮水所引起的慢性镉暴露不会对暴露人群引起健康危害。     

氨基改性Fe_(3)O_(4)纳米材料修饰电极同时测定Cd^(2+)和Pb^(2+)北大核心CSCD

采用溶剂热法一步合成氨基改性的Fe_(2)O_(4)(NH_(2)-Fe_(3)O_(4))纳米材料,通过扫描电镜、红外光谱、X射线衍射等方法对合成纳米材料进行表征,并将NH_(2)-Fe_(3)O_(4)滴涂在玻碳电极(GCE)表面制成电化学传感电极(NH_(2)-Fe_(3)O_(4)/GCE)。结果发现,NH_(2)-Fe_(3)O_(4)/GCE在最优条件下可以同时测定Cd^(2+)和Pb^(2+),Cd^(2+)在1.2×10^(-8)~9.6×10^(-5)mol·L^(-1)浓度范围内与峰电流值呈良好的线性关系(R=0.9949),检测限为1.4×10^(-9)mol·L^(-1);Pb^(2+)在4.8×10^(-8)~9.6×10^(-5)mol·L^(-1)时浓度范围内与峰电流值呈良好的线性关系(R=0.9843),检测限是2.7×10^(-9)mol·L^(-1)。     

黄瓜中敌敌畏残留的快速分析

构建了一种十六烷基三甲基溴化铵/植物酯酶修饰玻碳电极测定敌敌畏的方法,植物酯酶可使乙酸-1-萘酯水解为1-萘酚,敌敌畏使植物酯酶的活性降低,根据1-萘酚氧化峰电流峰值的降低值,可对敌敌畏进行定量分析.在最优条件下,敌敌畏的线性范围为1.0×10~(-9)～1.0×10~(-5) mol·L~(-1),检出限为3.0×10~(-10) mol·L~(-1).     

表面增强拉曼光谱法测定牛奶中青霉素G钠的残留量北大核心CSCD

青霉素G钠(NaBP)溶液的常规拉曼光谱信号微弱.将制备的浓缩银纳米粒子(AgNPs)20μL与不同浓度(1×10^(-9)~1×10^(-1)mol·L^(-1))的青霉素G钠溶液(pH 6)20μL混合,所得混合液的表面增强拉曼光谱(SERS)信号显著增强,在上述混合液中加入1×10^(-2)mol􀅰L^(-1)硫酸镁溶液8μL,青霉素G钠SERS增强效果最佳.据此,提出了以AgNPs为基底,硫酸镁为凝聚剂,采用SERS测定青霉素G钠含量的方法,并用于加标牛奶样品的检测.结果表明,青霉素G钠浓度为1×10^(-8)~1×10^(-3)mol·L^(-1)时,其浓度的对数值与相应的SERS信号强度呈线性关系,检出限(3s/k)为8.2×10^(-9)mol·L^(-1).按标准加入法进行回收试验,回收率为80.0%~96.0%,测定值的相对标准偏差(n=5)为2.3%~6.5%.     

金纳米粒子/石墨烯量子点复合修饰电极检测NO_(2)^(-)北大核心CSCD

采用微波加热石墨烯量子点还原HAuCl_(4)的方法,制备金纳米粒子/石墨烯量子点(AuNPs/GQDs)复合物,并将其应用于构建具有高灵敏度的NO_(2)^(-)电化学传感器。由于GQDs大的比表面积和AuNPs良好的导电能力,合成的AuNPs/GQDs复合材料显著提高了NO_(2)^(-)的电化学响应。利用循环伏安法研究NO_(2)^(-)在AuNPs/GQDs修饰电极上的电化学性质,发现在电位1.22 V处出现一个明显的氧化特征峰,其氧化峰电流与NO_(2)^(-)浓度成线性关系,线性范围为1.0×10^(-7)~1.0×10^(-5) mol/L,检测限(S/N=3)为5.0×10^(-8) mol/L。将该方法应用于土壤中NO_(2)^(-)的检测,具有较好的准确度。     

Uptake of lead and arsenic in food plants grown in contaminated soil from Barber Orchard, NC

Elevated levels of heavy metals in soil may allow uptake of these toxic species in food plants. Barber Orchard, Haywood County, NC has been designated a U.S. EPA Superfund site, primarily because of elevated levels of lead and arsenic. In this work, carrots, lettuce, and tomatoes were cultivated in a greenhouse in control soil and soil obtained from Barber Orchard. The resulting samples were then analyzed for lead and arsenic using inductively coupled plasma optical emission spectrometry (ICP-OES). Except for carrot roots grown in the contaminated soil, the concentrations of lead and arsenic in the plants were below the ICP-OES detection limit. The concentration of lead in carrot roots was 20 ± 11 μg/g, which represents a bioconcentration factor (BCF) of 0.03.     

Effect of Environmental Pollution on Heavy Metals Content of Withania Somnifera

Heavy metals were investigated in the medicinal plant Withania somnifera as well as of the soil it was grown in using atomic absorption spectrophotometer. The plant samples were collected from three different locations of N.W.F.P, Pakistan. The plant parts including roots, stem, leaves and fruits were found to have the quantity of heavy metals corresponding to their content in the soil. The purpose of the study is to create awareness among people about the proper use and collection of medicinal plants containing high levels of heavy metals and their adverse health affects.     

Sources of Soil and Plant Contamination in an Urban Environment and Possible Assessment Methods

Abstract

A survey was carried out in the city of Brno, Czech Republic in order to determine the levels and sources of soil and plant contamination and the possible implications for human health. A group of 136 topsoil and plant samples were taken in a defined sampling pattern, both in urban (in the year 1991) and suburban (1992) areas, paying particular attention to traffic density and intensity of land use. Samples were analysed for the contents of six heavy metals (Cd, Cu, Cr, Ni, Pb, Zn) and polycyclic aromatic hydrocarbons. The main soil characteristics were also determined (p^H, CEC, C_ox).

Traffic influence indices (TII) were calculated for each locality based on the traffic density and micro climatic conditions. Soil pollution indices (SPI) and plant pollution indices (PPI) were defined as a loading of a group of toxic metals relative to acceptable upper limits and were used as a general measure of the soil and plant burden at a particular site.

There were significant differences between the level of pollution in urban and suburban areas particularly for Pb, Cr and Ni in plants.

Traffic was found to be the major source of pollution by Pb, Zn and Cu in the urban survey and significant correlations were found between soil Pb × TII and SPI × TII in urban area. No such relationships were found for the suburban samples.     

Heavy Metal Contamination and Accumulation in Soil and Plant Species from the Xinqiao Copper Deposit,Anhui Province,China

The distribution and accumulation of heavy metals in soil and various plants were investigated in Xinqiao, the location of one of the largest copper deposits in China. The concentrations of cadmium, copper, lead, and zinc were determined by inductively coupled plasma–mass spectrometry (ICP–MS), and the results suggest that the soil was contaminated by mining activities. Plants grown around the study area accumulated these metals at various concentrations. The concentrations of metals in the plants indicated that the accumulation levels were not consistent with the relative concentrations in the corresponding soils. Almost all plants primarily accumulated heavy metals in above-ground tissues, especially Commelina communis. High biological transfer coefficients for Buddleja davidii, Rumex acetosa, Debregeasia edulis, Commelina communis, and Rosacfolius smith for some metals indicate accumulation in stems and leaves and identify these plants as hyperaccumulators.     

Feasibility study on reducing lead and cadmium absorption by spinach (Spinacia oleracea L.) in a contaminated soil using nanoporous activated carbon

Activated carbons (AC) have been long recognized as prominent absorbents in industries and feature numerous applications in preventing or absorbing the harmful gases and liquids and could be employed for filtration and remediation or even reutilization of chemicals. In order to investigate the capacity of AC in reducing the absorption of heavy metals (HM) including lead (Pb) and cadmium (Cd) and dual complex (Pb?×?Cd) by spinach, a factorial experiment in a completely randomized design with three replications on a pot trial was conducted. Three factors including five levels of AC 0, 5000, 10000, 15000, 20000?mg/kg soil, one concentration level of Pb 4,000?mg/kg soil and one concentration level of cadmium Cd 8?mg/kg soil were tested. The index of heavy metal concentration was calculated in leaf, stem and root and their corresponding dry weights. Results illustrated that in contaminated soils, plants with AC exhibited a superior reduction of absorption of HM vis-à-vis the plants without AC. The foremost result regarding the impact of AC on reducing the concentration of Pb and Cd was observed in 20,000 level of AC. This reveals that AC declined the soil contamination and lessened the accumulation of HM into the shoots and roots. Results suggest that the application of AC may be an eligible solution for decreasing the translocation of HM into the plants.     

Uptake,Translocation, and Bioaccumulation of Elements in Forest Nettle (Laportea alatipes)

Elements found in the edible parts of plants are considered to be the main source of nutrients for humans and animals. However, there is insufficient information on the relationship between heavy metal pollution in the growing soil of most edible plants. In this study, the distribution of elements in the edible forest nettle (Laportea alatipes) was evaluated as a function of geographical location. Forest land soils had higher concentrations of minor elements (Cu, Cr, Ni, and Zn) compared to soils from rural and suburban areas. Translocation factors for Cd and Pb showed effective translocation from the roots to the leaves; however, these heavy metals in leaves were still above South African maximum permissible levels for vegetables. Atmospheric depositions may play a significant role in higher Cd and Pb concentrations in the leaves. Bioaccumulation factors showed the plant to accumulate Cu, Mn, and Zn to meet physiological requirement levels. Geoaccumulation indices and enrichment factors showed no soil contamination or minimal enrichment by trace metals. Principal component analysis showed Co, Cr, Cu, Fe, Ni, Pb, and Zn in soil to originate from a common source which may be soil silicates and other minerals.     

Labile rhizosphere soil solution fraction for prediction of bioavailability of heavy metals and rare earth elements to plants

A labile rhizosphere soil solution fraction has been recommended to predict the bioavailability of heavy metals and rare earth elements to plants. This method used moist rhizosphere soil in combination with a mixture of 0.01 mol L(-1) of low-molecular-weight organic acids (LMWOAs) as extractant. The extracted soil solutions were fractionated into two colloidal fractions of <0.45 microm (F(3)) and <0.2 microm (F(2)), and one truly dissolved fraction including free metal ions and inorganic and organic complexes (fractionr(0.2 microm, LMWOAs) approximately r(0.45 microm, LMWOAs). In the case of rare earth elements the good correlation was obtained for both the wheat roots and shoots. Generally, the correlation coefficients obtained by LMWAOs were better than that obtained by the first step of BCR method. Therefore, LMWAOs and F(lrss) were strongly recommended to predict the bioavailability of metals in soil pools to plants.     

The protective role of melatonin under heavy metal-induced stress in Melissa Officinalis L.

Heavy metals, due to their inability to degrade, pose a serious environmental and nutritional problem. The accumulation of essential and non-essential heavy metals in living organisms reduces normal growth and development, resulting in acute poisoning, disease and even death of organisms. Melatonin is a very important multifunctional molecule in protecting plants from oxidative stress due to its ability to directly neutralize reactive oxygen species (ROS). Also, melatonin has a chelating property, which may contribute in reducing metal-induced toxicity. In this paper, the protective role of melatonin in counteracting metal-induced free radical generation was highlighted. Using the HPLC-FLD technique melatonin was identified and quantified in the roots and leaves of lemon balm ( Melissa officinalis L.), grown under photoperiod conditions. Furthermore, the response of plants pre-treated with exogenous 0.1 mM melatonin to the increased zinc (Zn) and cadmium (Cd) concentrations was observed, with changes in mineral (Ca, Mg), physiological and antioxidant status of the plant during heavy metals stress. The obtained melatonin concentrations were the highest published for dry plants so far. Elevated Cd and Zn levels in soil caused alternation in biochemical and physiological parameters of lemon balm leaves and roots. However, melatonin pre-treatment increased plant tolerance to heavy metals stress. Increased Cd and Zn uptake and their translocation into the leaves were also improved, indicating the possible use of melatonin in phytoremediation.     

Characterization of Heavy Metals in Soil Near Coal Mines and a Power Plant in Huainan,China

The environmental and health hazards posed by heavy metals are significant due to their toxicity and bioavailability. Thirty-two soil samples were collected from residential areas around three coal mines and a power plant to assess the environmental and health implications caused by mining activities. The concentrations of heavy metals in soil were determined by inductively coupled plasma mass spectrometry. To evaluate the risk levels, the geo-accumulation index and health risk assessment were determined. The concentrations of metals in power plant soil were generally higher than those in coal mine soil, suggesting a higher release during coal combustion. The results demonstrate that the soils in the vicinity of Xinzhuangzi Mine and Luohe Power Plant are moderately contaminated by arsenic and cadmium. The analysis of the health risk of the metals indicated that the non-carcinogenic and carcinogenic adverse effects to residents due to heavy metal exposure are negligible. However, more attention should be paid around the power plant for the unacceptable level of carcinogenic risk. Based on the results of the environmental and health risk assessment, priority control components in Huaian have been identified. The study provides a comprehensive assessment of soil heavy metal implications derived from mining activity in this region in China and is helpful for pollution control and environmental management.