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1.
Aubry Vanderstraeten Steeve Bonneville Stefania Gili Jeroen de Jong Wendy Debouge Philippe Claeys Nadine Mattielli 《Geostandards and Geoanalytical Research》2020,44(2):307-329
Atmospheric dust is an integral component of the Earth system with major implications for the climate, biosphere and public health. In this context, identifying and quantifying the provenance and the processes generating the various types of dust found in the atmosphere is paramount. Isotopic signatures of Pb, Nd, Sr, Zn, Cu and Fe are commonly used as sensitive geochemical tracers. However, their combined use is limited by the lack of (a) a dedicated chromatographic protocol to separate the six elements of interest for low‐mass samples and (b) specific reference materials for dust. Indeed, our work shows that USGS rock reference materials BHVO‐2, AGV‐2 and G‐2 are not applicable as substitute reference materials for dust. We characterised the isotopic signatures of these six elements in dust reference materials ATD and BCR‐723, representatives of natural and urban environments, respectively. To achieve this, we developed a specific procedure for dust, applicable in the 4–25 mg mass range, to separate the six elements using a multi‐column ion‐exchange chromatographic method and MC‐ICP‐MS measurements. 相似文献
2.
太湖MS岩芯重金属元素地球化学形态研究 总被引：21，自引：4，他引：17
采用BCR三步提取法对太湖MS岩芯沉积物中Cu、Fe、Mn、Ni、Pb和Zn等6种重金属元素的化学形态进行了研究.结果表明,有效结合态的Cu、Ni和Pb主要以有机物及硫化物结合态、Fe-Mn氧化物结合态存在,Fe和Zn主要以Fe-Mn氧化物结合态存在,Mn主要以可交换态及碳酸盐结合态存在;Fe-Mn氧化物结合态的Ni、Pb和Zn与可还原态的Mn有较好的正相关关系,有机物及硫化物结合态的Cu、Mn、Ni、Pb和Zn与有机碳含量有较好的正相关关系;重金属形态分布体现了重金属元素地球化学性质的差异,以及重金属形态含量与沉积物理化性质的关系.沉积岩芯重金属元素形态垂向变化规律及次生相富集系数表明,Cu、Mn、Ni、Pb和Zn在沉积岩芯13～4 cm有效结合态含量较稳定,为自然沉积;4～0 cm有效结合态含量明显升高,存在一定程度的人为污染.根据137Cs测年结果判断,沉积岩芯Cu、Mn、Ni、Pb和Zn等重金属污染开始于20世纪70年代末期,主要污染元素及污染历史与太湖流域污染工业类型及经济发展阶段相吻合. 相似文献
3.
Jason Jweda Louise Bolge Cornelia Class Steven L. Goldstein 《Geostandards and Geoanalytical Research》2016,40(1):101-115
The Lamont‐Doherty Earth Observatory radiogenic isotope group has been systematically measuring Sr‐Nd‐Pb‐Hf isotopes of USGS reference material BCR‐2 (Columbia River Basalt 2), as a chemical processing and instrumental quality control monitor for isotopic measurements. BCR‐2 is now a widely used geochemical inter‐laboratory reference material (RM), with its predecessor BCR‐1 no longer available. Recognising that precise and accurate data on RMs is important for ensuring analytical quality and for comparing data between different laboratories, we present a compilation of multiple digestions and analyses made on BCR‐2 during the first author's dissertation research. The best estimates of Sr, Nd and Hf isotope ratios and measurement reproducibilities, after filtering at the 2s level for outliers, were 87Sr/86Sr = 0.705000 ± 11 (2s, 16 ppm, n = 21, sixteen digestions, one outlier), 143Nd/144Nd = 0.512637 ± 13 (2s, 25 ppm, n = 27, thirteen digestions, one outlier) and 176Hf/177Hf = 0.282866 ± 11 (2s, 39 ppm, n = 25, thirteen digestions, no outliers). Mean Nd and Hf values were within error of those reported by Weis et al. (2006, 2007) in their studies of RMs; mean Sr values were just outside the 2s uncertainty range of both laboratories. Moreover, a survey of published Sr‐Nd‐Hf data shows that our results fall within the range of reported values, but with a smaller variability. Our Pb isotope results on acid leached BCR‐2 aliquots (n = 26, twelve digestions, two outliers) were 206Pb/204Pb = 18.8029 ± 10 (2s, 55 ppm), 207Pb/204Pb = 15.6239 ± 8 (2s, 52 ppm), 208Pb/204Pb = 38.8287 ± 25 (2s, 63 ppm). We confirm that unleached BCR‐2 powder is contaminated with Pb, and that sufficient leaching prior to digestion is required to achieve accurate values for the uncontaminated Pb isotopic compositions. 相似文献
4.
《Chemie der Erde / Geochemistry》2016,76(4):481-489
Risk assessment of metals associated to airborne particulate matter (PM) has usually been based on the analysis of their total concentrations, which is a poor indicator of metal mobility. Chemical fractionation processes may provide an additional level of information, however, chemical complexity and small sample sizes do not allow to combine several extraction methods. Additionally, analysing the metal concentrations during the extractions exceptionally provides restricted information about metals’ speciation. To overcome these limitations we collected total suspended particulate matter (TSP) samples from the air filters placed in the air supply channel of methane-heated turbines of thermal power stations which allows collecting large amounts of TSP materials. Additionally, we combined single and sequential chemical extractions in which not only the concentrations of potentially toxic elements (PTE) (Cd, Cr, Cu, Ni, Pb, Zn) but also that of the major chemical components (Al, Ca, Fe, K, Mg, Mn, Na, P, S, Ti) were analysed. Our aims were to study these metals’ mobility and speciation through the study of their association to major chemical components.Accumulation of the studied PTEs in the TSP material suggests moderate contamination for Ni, Cd and Cr whereas a heavy one for Cu, Zn and Pb. Three groups of these PTEs could be distinguished based on their mobility. The highly mobile Zn and Cd (large ratios of water and weak acid soluble fractions) can be considered as especially harmful elements to environment. The moderately mobile Pb and Cu (large ratios of reducible and oxidizable fractions, respectively) may potentially have a negative effect on the environment, whereas the immobile Cr and Ni cannot be expected to pose a serious risk. Based on the statistical evaluation of extraction data, the potential phases for Zn and Cu are presented by metal-sulphates, -nitrates, -chlorides, -carbonates and -hydroxides, as well as sorbed forms. Lead primarily hosted by metal-carbonates and sorbed forms, as well as by -hydroxides, whereas Cu by organic matter. Finally, Cr and Ni are mostly incorporated into very resistant phases, most probably by magnetite or other resistant metal-oxides.Combination of single and sequential extractions, as well as that of the analysis of not only the target elements but also the major chemical components were found to be a very effective tool to study the host phases of PTEs in the TSP material. The necessity for relatively large sample amounts for such analyses could be fulfilled using special sampling methodology; however, obvious disadvantages of this kind of sampling must be taken into account when resulted data are evaluated. 相似文献
5.
Dorrit E. Jacob 《Geostandards and Geoanalytical Research》2006,30(3):221-235
Fifty-two trace elements in NIST SRM 614, 616 and MPI-DING BM90/21-G glass reference materials as well as in NIST SRM 612, USGS BCR2-G and other MPI-DING reference glasses (KL2-G, GOR132-G, GOR128-G, ATHO-G, Tl-G, StHs6/80-G and ML3B-G) were determined by laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS). Accurate ultra-low trace element abundances in the NIST SRM 614, 616 and BM90/21-G reference glasses down to lower ng g−1 levels were determined with relative standard deviations (RSD) of less than 10%. Limits of detection using He as carrier gas were up to two times lower than with Ar and were 0.004 to 0.12 μg g−1 for elements of lower mass numbers (amu < 85) and 0.002 to 0.06 μg g−1 for elements having amu < 85. The measured concentrations generally agree within 15% with previous studies except for B in NIST SRM 614 and 616, which appears to be heterogeneously distributed, and Co, Zn, Ga and Ag in NIST SRM 616 for which the existing data set is too small to evaluate the discrepancies. New values for As (0.593 μg g−1 ), Ag (0.361 μg g−1 ) and Cd (0.566 μg g−1 ) in NIST SRM 614 and new values for Na (94864 μg g−1 ) and As (0.276 μg g−1 ) in NIST SRM 616 are reported. 相似文献
6.
The European Water Framework Directive (WFD) commits European Union member states to achieving good ecological status in all water bodies by 2015. For sediments the definition of good chemical status is based on numerical sediment quality guidelines. The aqua regia fraction is thus used for the evaluation of heavy metal concentrations in sediments. The chemical constituents in sediments responsible for mobility and toxicity are not considered generally. This article presents the combining of the sequential BCR procedure, for determining the chemical species of relevant elements, with the geoaccumulation index principle a numerical classification method for sediment quality guidelines. Using the BCR method it can be demonstrated that changes in element speciation can lead to more highly mobile species of trace elements which may affect the hazardous potential of sediments despite the “good chemical status” classification for aqua regia digestions. The Klinke stream is an urban surface water body located in Magdeburg, the state capital of Saxony‐Anhalt, Germany. Using this stream as an example it is shown that this additional information helps to describe the dynamics and discharge of the trace elements Al, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Rb, Sr, Mo, Pd, Cd, Sb, Ba, Pb, Bi, and U into the Elbe River from urban water bodies. 相似文献
7.
边缘海（黄、东海）沉积物可以提供水体中广泛的信息。Tessier和BCR方法被广泛的应用于沉积物中不同地球化学相的提取。为了选取适用于第四纪大陆架沉积物不同相态的提取方法，我们进行了两种方法提取典型单一矿物的有效性和选择性实验，并且对每种方法提取天然沉积物（沉积物标准品GSD-9和3个表层沉积物）进行了评价，分析了提取液中地球化学代表性元素Ca、Fe、Mn、Al、Ti。结果表明，两种方法提取不同的地球化学相均具有很好的选择性和有效性，并且给出了两种方法每个形态的提取试剂体积的最佳用量。考虑到实际研究中吸附-解吸过程的重要性，我们推荐Tessier方法，同时利用Tessier方法提取表层沉积物提供了生产力和沉积物环境方面的信息。以上结果进一步说明Tessier方法适用于中国大陆架沉积物元素形态的提取。 相似文献
8.
攀枝花公园土壤中钒的地球化学形态及潜在生态风险 总被引：3，自引：0，他引：3
钒是人和动物必需的微量元素,但过量又会给动植物及人体健康造成损害.近年来随着钒矿的开采,土壤钒污染及其危害日益受到人们的重视.采用改进的BCR方法(按顺序提取元素形态的方法),系统测定旱季和雨季攀枝花公园土壤中钒的地球化学形态,研究土壤中钒地球化学形态的分布及变化特征,以此评价土壤钒污染及潜在生态危害.结果表明:土壤中不同形态钒的含量顺序为残渣态可氧化态可还原态酸可溶态,旱季和雨季土壤中钒的形态变化不明显;攀枝花公园入口处各形态钒的质量分数均较高,与该处人员流动密度大有一定的关系,而在儿童游乐区、休闲区、休憩区各形态的钒无明显的高异常;采用中国土壤背景值计算得到的土壤中钒的污染指数较高,超标率为100%,而采用加拿大城市公园土壤中钒环境质量标准计算得到的污染指数较低,但仍有近一半的样点超标,雨季较旱季钒的污染指数高;通过风险评估编码方法得到的土壤中钒的生态风险为低风险等级,应引起注意. 相似文献
9.
改进BCR法测定公路两旁表层土壤中铂钯铑的化学形态 总被引：3，自引：2，他引：1
铂、钯、铑是汽车催化转换器中的主要成分,在有效治理汽车尾气污染的同时,不断排放并在环境中累积增加,随着元素的迁移、转化及地下水的循环,可能成为一种新的环境污染问题.本文将改进的BCR顺序提取法应用于铂族元素形态分析,结合铂族元素的性质,将公路两旁表层土壤样品中Pt、Pd、Rh分为酸溶态、可还原态、可氧化态和残渣态四种形态.实验优化了原始的BCR浸取条件,利用电感耦合等离子体质谱法测定Pt、Pd、Rh的各形态.各形态的精密度、检出限满足地质矿产实验室测试质量管理规范的监控要求,各形态浸取量之和与样品各元素的总量之比(回收率)在95.3％ ～ 110.0％,说明方法具有较好的准确性和重现性.通过实际样品分析,公路两旁表层土壤样品中铂族元素非残渣态含量顺序为Pd (57.23％ ～ 58.03％)＞Rh (22.64％ ～25.80％) ＞Pt(17.91 ～20.57％),研究认为铂族元素进入生物圈的几率是Pd＞ Rh＞ Pt. 相似文献
10.
Antonio M. Álvarez-Valero Reinaldo Sáez Rafael Pérez-López Joaquín Delgado José M. Nieto 《Journal of Geochemical Exploration》2009
The beginning of polymetallic sulphide ore exploitation at Almagrera, Iberian Pyrite Belt, SW Spain, has been dated back to pre-Roman times; mining activity lasted until 2001 when it was definitely halted. The Almagrera sulphide tailings dam was built at the Sotiel–Coronada mine, where Cu, Zn and Pb concentrates were obtained by flotation processes, and sulphide (mainly pyrite) wastes formed. The dam was built as a water-reservoir, on a tectonic fault; its hazard is currently documented by the released wastes after a strong storm in the region, then, its stability is not monitored by the owner. 相似文献