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1.
Phosphogypsum (PG) is a by-product of the phosphate fertilizer industry. In Brazil, three main phosphate industries are responsible for the production of 5.5 × 106 metric tons of PG per year, which is stored in stacks. Part of this by-product can be reused to improve fertility of agricultural soils. For its safe application, it is necessary to characterize the impurities (metals and radionuclides) present in PG and to evaluate their availability to the environment. The main objectives of this paper are: to determine the total concentration of radionuclides (226Ra, 228Ra and 210Pb) and metals (As, Cd, Cr, Co, Cu, Hg, Ni, Pb, Se, Zn) in the Brazilian PG samples using different methodologies, to evaluate the available fraction of these elements in the PG samples using a methodology with mild leaching with EDTA, to compare the results obtained for PG samples with those obtained for the most used phosphate fertilizers. The total concentration obtained for the metals using methodologies with different initial digestion (strong attack with acids and HF and mild attack with nitric acid) are slightly different. The results obtained using the methodology with mild leaching showed that the metals and radionuclides are not available to the environment, giving evidence that the application of PG in agriculture is safe as far as contamination by such elements. PG presented metals concentration lower than the phosphate fertilizers. The results obtained for the PG samples, for As, Cd, Cr, Hg, Ni, Pb and Se, are below the limits established by the Brazilian Regulatory Agency.  相似文献   

2.
The present paper describes radiochemical separation procedures developed for the determination of seven elements: As, Cd, Cr, Cu, Hg, Sb and Se in different Brazilian regional diets. In the case of the elements As, Hg, Sb and Se, the procedure was based on retention in inorganic exchanger TDO (tin dioxide) and determination of Hg by extraction with Ni(DDC)2. For determination of Cd, Cr, Cu and Se the procedure chosen was based on retention in inorganic exchanger HMD (hydrated managese dioxide) and extraction of Cu and Cd as diethyldithiocarbamate compounds. The accuracy and precision of the methods studied were tested by means of analyses of different reference materials. Due to the lack of data on trace element levels in Brazilian foodstuffs and diets, these methods were applied to determination of these elements in different Brazilian regional diets. These diets were supplied by the Food and Experimental Nutrition Department of the Faculty of Pharmaceutical Science, University of São Paulo. The daily dietary intake values for these diets are presented for As, Cd, Cr, Cu, Hg, Sb and Se.  相似文献   

3.
目前由人工合成的有机螯合微量元素肥料,因价格昂贵不能在农业生产中广泛应用。本研究采用丰富廉价的有机肥料,经转化提取的天然螯合剂与微量元素螯合研制的天然螯合微肥,在多种作物上施用,证明能促进作物对N、P、K和Fe、Mn、Zn、Cu等微量元素的吸收。明显提高作物的产量,改善品质,并不同程度地提高作物的抗病能力.  相似文献   

4.
目的:通过测定缅甸进口姜黄中26种无机元素,并对进口姜黄中重金属含量进行风险评价,为缅甸进口姜黄的质量控制奠定基础。方法:采用微波消解ICP-MS法对24批来自缅甸地区的姜黄进行26种无机元素的测定,通过靶标危害系数(THQ)和总危害指数(HI)对Pb、Cd、Cu 3种元素进行非致癌风险评价,用终生致癌风险(R)对As进行致癌风险评价。结果:结果表明,缅甸进口姜黄中含有24种无机元素,其中K、Na、Mg、Ca 4种营养元素含量占比24种无机元素的92.39%。缅甸姜黄中均未检出Sn、Hg 2种金属元素,Pb、Cd、As、Cu 、Hg5种重金属元素含量均符合2020版中国药典限定值。经过缅甸姜黄中Cu、Pb、Cd 3种重金属元素健康风险评价,THQ和HI均小于1,表明人体通过缅甸姜黄摄入的Cu、Pb、Cd不会对人体造成非致癌伤害。经过对姜黄中As的致癌健康风险评价,致癌风险R为7.72 x10-6,低于世界卫生组织建议的致癌风险值(1.00 x 10-5),通过缅甸姜黄摄入的总As不存在致癌风险。结论:总体而言,缅甸进口姜黄重金属元素保持在较好水平。  相似文献   

5.
Instrumental neutron activation analysis (INAA) with gamma-ray spectrometry was applied to determine As, Ca, Cd, Cl, Co, Cu, Cr, Fe, Hg, K, Mg, Mn, Mo, Na, Sb, Se and Zn in the Brazilian agroindustrial by-products. These materials are widely used in ruminant feeding. The results obtained were compared with requirement and maximum tolerable concentrations. The general conclusions from the data obtained were: (1) many by-products presented concentrations of some essential elements lower than the requirement concentrations, while in some concentrations of Cr, Fe, Mg and Se exceeded by a little the maximum tolerable concentrations, (2) the elements As, Cd, Hg and Sb, generally considered toxic, showed concentrations lower than maximum tolerable values.  相似文献   

6.
Instrumental neutron activation analysis (INAA) have been used to determine As, Br, Hg, Sb and Se in combination with atomic absorption spectrometry (AAS) as a complementary technique for the quantification of Cd and Pb in jaggery, brown sugar, white sugar and molasses. All sugar cane products were collected from the local sugar cane industry of Pakistan. The highest concentration of these potentially toxic elements was quantified in molasses; however, molasses together with jaggery, brown sugar and white sugar contains trace amounts of all of these elements. Due to very low concentration of Cd it could only be detected in molasses. To evaluate the percentage contribution of these elements in the sugar cane products to the weekly recommended values, intakes on weekly consumption of 100 g of each item have also been calculated which follow the pattern Br>Se>Pb>Hg>As>Sb. The elevated Br contents may be attributed to the use of Br-containing chemicals for fumigation; however, these contents are well within the tolerance levels. The estimated weekly intake of all toxic elements is very low indicating that sugar cane products can be safely ingested as part of the diets.  相似文献   

7.
建立电感耦合等离子体原子发射光谱法(ICP-AES)测定血藤类中药中K,Ca,Mg,P,Sr,Fe,Mn,Zn,Cu,Co,Cr,Al,Ba,Ni,As,Pb和Cd 17种常量和微量元素含量的分析方法。样品用微波辅助消解,ICP-AES法检测几种血藤中17种元素的含量,方法的检出限为0.000 03~0.009 81μg/mL,加标回收率88.37%~110.00%,相对标准偏差(RSD)均小于5.0%,方法可快速、灵敏、准确测定血藤类中药中多种常量、微量元素的含量。血藤样品中除含有人体必需的常量元素K,Ca,Mg外,还含有Fe,Zn,Mn,Cr,Co等必需的微量元素和其它元素P,Ni,Ba,Al,Sr,Pb,Cd,Ba等。  相似文献   

8.
Instrumental neutron activation analysis (INAA) was applied to determine the elements Br, Ca, Cl, Cu, Fe, I, K, Mg, Mn, Na, Rb, S, V, Zn in five varieties of Brazilian corn, resulting from the studies carried out in order to increase their protein contents. The accuracy of the method was evaluated by means of reference material analysis. In general, the precision of the method was lower than 15%, except for Cu, I and S. Sensitivity and detection limit were also determined. Besides, tryptophan contents were determined. It was observed that the tryptophan content in improved corn samples was twice as large as in the normal samples. However, the same ratio was not observed in the inorganic element contents.  相似文献   

9.
采用微波消解样品,运用电感耦合等离子体原子发射光谱法同时测定山药中K,Na,Ca,Mg,Zn,Fe,Cu,Mn,Se,Pb,Cd和Cr 12种元素。结果表明:方法简便、快速、准确;山药富含对人体有益的K,Ca,Fe,Mg,Zn,Mn,Se等矿物质元素,其肉质中重金属元素Pb,Cd,Cr含量均未超过国家食品卫生标准。  相似文献   

10.
The single extraction procedures validated by the standards, measurement and testing programme (formerly BCR), extraction with 0.05 mol l−1 EDTA and 0.43 mol l−1 acetic acid, have been applied to reference materials of soils and sludges with certified total values of elements, in order to determine bioavailable contents of Cd, Cu, Ni, Pb and Zn. These soils, which represent uncontaminated pedologically different types of soils from Slovakia and sludges from city water treatment are characterized for the bioavailable fraction of the metals using the procedures followed by SM&T Programme. Concentrations of the elements under the study in the extracts were determined by flame (FAAS) using calibration curves in appropriate extractants and by electrothermal (ETAAS) atomic absorption spectrometry, using technique of standard additions for the evaluation of the results. The accuracy of the extraction procedures and determinations of the elements in the extracts was controlled using CRM 483 certified for EDTA- and acetic acid-extractable contents of Cd, Cu, Ni, Pb and Zn in sewage sludge amended soil.  相似文献   

11.
The concentration of 35 elements (Al, As, B, Ba, Be, Ca, Cd, Co, Cl, Cr, Cu, Fe, K, Mg, Mn, Mo, N, Na, Ni, P, Pb, Rb, S, Sb, Sc, Si, Sr, Tb, Th, Ti, U, V, Yb, Zn and Zr) in six different imported, NPK, NP and K fertilizers were determined by ICP-OES in two different laboratories and by INAA. The fertilizers were labeled as 24/12 (Belgium), 46/18 (Morocco), 50% ammonium sulfate 50% K2O (Belgium), New 24/12 (Belgium), 16.8.24 (France) and 17.17.17 (France). It is clear that these fertilizers vary widely in their heavy metals and uranium content, and the accumulation of certain elements in vitally important media such as water, soil and food is undesirable from the medical point of view. The results obtained were acceptable and intercomparison between various methods was carried out.  相似文献   

12.
Composition of phosphate rocks mostly depend on their type and origin. Sedimentary rocks contain high concentration of heavy metals. Phosphate rocks are mainly used for the manufacturing of phosphate fertilizers. The contents of heavy metals Cd, Co, Cu, Fe, Mn, Ni, Pb and Zn, as well as rare earth elements Ce, La, and Th were determined in sedimentary phosphate rock used for production of fertilizer in Turkey. The Kasrik-Semikan, Mazidag (Mardin, SE Anatolia, Turkey) high-grade phosphate rock used in this study is situated near the border with Syria and was deposited during the Turonian and Senonian (Cretaceous) ages. Total phosphorus (P) concentration in the rock is 18.5% on the average. Microwave acid digestion (MW-AD) followed by ?nductively Coupled Plasma-Optical Emission Spectrophotometry (ICP-OES) was carried out for the determination of all the elements of interest in phosphate rock. The results revealed that hazardous metal content of the phosphate rock was lower in Mazidag phosphate than that in samples imported from other countries and were within the safety limits.  相似文献   

13.
14.
Previous studies have revealed considerable Cd isotope fractionations in seawater, which can be used to study the marine cycling of this micronutrient element. The low Cd concentrations that are commonly encountered in nutrient-depleted surface seawater, however, pose a particular challenge for precise Cd stable isotope analyses. In this study, we have developed a new procedure for Cd isotope analyses of seawater, which is suitable for samples as large as 20 L and Cd concentrations as low as 1 pmol/L. The procedure involves the use of a 111Cd–113Cd double spike, co-precipitation of Cd from seawater using Al(OH)3, and subsequent Cd purification by column chromatography. To save time, seawater samples with higher Cd contents can be processed without co-precipitation. The Cd isotope analyses are carried out by multiple collector inductively coupled plasma mass spectrometry (MC-ICP-MS). The performance of this technique was verified by analyzing multiple aliquots of a large seawater sample that was collected from the English Channel, the SAFe D1 seawater reference material, and several samples from the GEOTRACES Atlantic intercalibration exercise. The overall Cd yield of the procedure is consistently better than 85% and the methodology can routinely provide ε 114/110Cd data with a precision of about ±0.5 ε (2sd, standard deviation) when at least 20–30 ng of natural Cd is available for analysis. However, even seawater samples with Cd contents of only 1–3 ng can be analyzed with a reproducibility of about ±3 to ±5 ε. A number of experiments were furthermore conducted to verify that the isotopic results are accurate to within the quoted uncertainty.  相似文献   

15.
建立电感耦合等离子体质谱法(ICP-MS)测定不同产地和批次地龙药材中铅(Pb)、砷(As)、汞(Hg)、镉(Cd)、铜(Cu)5种重金属元素的含量.采用微波消解进行样品前处理,结果表明:5种重金属元素的线性关系良好(r≥0.999 6),平均回收率在92.8%~95.2%范围内,方法的检出限在0.001 0~0.092 mg/kg范围内.方法灵敏度高,重复性好,方法准确.不同产地和批次的样品中5种重金属元素均有检出.地龙药材中Pb、As、Hg、Cd、Cu这5种重金属元素需要重点监控.  相似文献   

16.
The objective of this study was to determine the trace element composition and the toxic metal residues in Galician cow’s milk cheese produced in different systems (artisan, industrial, and organic). Fourteen elements (As, Cd, Co, Cr, Cu, Fe, Hg, I, Mn, Mo, Ni, Pb, Se, and Zn) were determined in 58 representative samples of Galician cheeses by inductively coupled plasma mass spectrometry. The toxic elements were present at low concentrations, similar to those reported for other unpolluted geographical areas. The essential elements were also within the normal range in cheeses. There were no statistically significant differences between smoked and unsmoked cheeses for any of the elements. Chemometric analyses (principal component analysis and cluster analysis) revealed that the industrial cheeses produced in Galicia using the milk from intensive dairy farms were different, in terms of elemental content, from artisan and organic cheeses, in which the elemental contents were similar.  相似文献   

17.
Several wines produced in different regions from south of Brazil and available in markets in Rio de Janeiro were analyzed for their contents of elements such as: P, S, Cl, Ca, Ti, Cr, Mn, Fe, Ni, Cu, Zn, Rb and Sr. Multi-element analysis was possible with simple sample preparation and subsequent analysis by total-reflection X-ray fluorescence using synchrotron radiation. The measurement was carried at the X-ray fluorescence beamline in the Synchrotron Light Source Laboratory in Campinas, Brazil. The levels of the various elements obtained were lower in the Brazilian wines than the values generally found in the literature. The present study indicates the capability of multi-element analysis for determining the contents of various elements present in wines coming from Brazil vineyards by using a simple, sensitive and precise method.  相似文献   

18.
Summary Instrumental neutron activation analysis (INAA) was to determine the nutrient status of six varieties of plantain. A total of 12 minerals were detected in both the pulp and the peel although their concentrations differed from variety to variety. Of these elements, only two (Mg and Cl) were classified, as macronutrients while seven (Cr, Zn, Se, Fe, Co, Mn, and Cu) were micronutrients essential for human life. The concentration of Cl, Mn and Cr in the edible pulp far exceeds the recommendations of the Subcommittee on Recommended Dietary Allowance (RDA). Aluminum, Br and Rb, which are neither classified as macro- nor micronutrients, were found in comparatively higher concentrations in the peel than is the pulp. The presence of seven micronutrients essential to human life in plantains makes it suitable for food, particularly in areas where micronutrient deficiencies may be prevalent.  相似文献   

19.
采用电感耦合等离子体原子发射光谱法测定胡蜂酒中20种无机元素,建立无机元素对照指纹图谱,对重金属元素进行风险评估。结果表明,胡蜂酒中无机元素种类丰富,其中P、K、Na元素占测定总元素的96.14%。有害元素Pb、Cd、As、Hg、Cu含量符合国家药典标准要求,Cu的靶标危险系数(THQ)为1.00×10-2,THQ<1说明摄入的重金属对人体健康造成的影响不明显。不同产区胡蜂酒金属元素含量存在差异,根据金属元素图谱得出元素含量按原子序数顺序出现相似的分布态势。结果表明,胡蜂酒中含有丰富的金属元素,很多为营养微量元素,有害元素(Pb、Cd、As、Hg、Cu)含量符合药典要求,从金属元素方面单一来看,饮用胡蜂酒没有明显的健康风险。胡蜂酒无机元素指纹图谱可为胡蜂酒的鉴别提供一定的的参考依据。  相似文献   

20.
基于秦皇岛滨海湿地人工种植耐高盐碱蓬修复工程试验,通过分析湿地土壤沉积物及耐高盐碱蓬中不同金属元素的含量与变化,研究了耐高盐碱蓬对金属元素的富集特征。结果显示:湿地沉积物中Fe、Mn、Cr、Pb和Zn的浓度较高,分别为8 210. 94、110. 04、8. 78、8. 25、10. 95 mg/kg,Cd的浓度最低,平均值为0. 022 mg/kg,湿地试验区土壤中同一金属元素变异程度较小,分布较均匀。碱蓬体内重金属含量根据采集地点的不同有差异,但与各站位中土壤的重金属分布特征存在正相关性;其中碱蓬内Fe、Mn、Zn、Cu的平均含量相对较高,且Fe、Mn、Ni、Cu、As、Cd、Pb元素在碱蓬根中的平均含量高于茎叶,而Cr在茎中的平均含量最高,Zn和Mo在叶中的含量最高。碱蓬的根、茎、叶对Cd的富集效果最好,其次为Mo、Cu,对Fe、Mn、Zn、As和Pb的富集效果相对较差,说明碱蓬对沉积物中不同金属元素的富集移出率存在差异。金属元素在碱蓬中的转移系数研究表明,Mo、Zn、Cd和Mn等元素可由根部转移到叶中,而Fe、Ni、Pb、As和Cu等金属元素固定在根部,该研究可为利用碱蓬修复湿地重金属污染提供理论基础。  相似文献   

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