牡蛎、缢蛏和菲律宾蛤仔中微量元素的分析研究

采用硝酸-高氯酸法消解样品,应用ICP—AES法测定了牡蛎、缢蛏和菲律宾蛤仔中Ca、Co、Cr、Cu、Fe、Mg、Mn、Ni、Se、Sr、V和Zn共12种微量元素。实验结果表明,3种贝类中均含有大量的Ca、Cu、Fe、Mn、Zn、Mg,还含有Co、Cr、Ni、Se、Sr和V等对人体有益的微量元素,是营养价值较高的海产品,可以作为人体补充微量元素的重要来源。     

INAA and ETAAS of toxic element content of fruits harvested and consumed in Pakistan

Instrumental neutron activation analysis (INAA) and electro-thermal atomic absorption spectrometry (ETAAS) were employed to determine the toxic elements in fourteen fruits harvested in Pakistan. As, Br, Hg, Sb and Se were determined using INAA. Cadmium and Pb were determined using ETAAS. The intake levels of all toxic elements have been calculated. The data show that dates supply the maximum amount of most of the toxic elements. Peels of apple and pear have also been investigated and were found to contain higher concentration of toxic elements than their edible parts. The reliability of the techniques has been established by the use of standard reference materials. This study shows that all investigated fruits cultivated and consumed in Pakistan are safe for human consumption.     

Use of combined NAA and SIMS analyses for impurity level isotope detection

Instrumental neutron activation analysis (INAA) and electro-thermal atomic absorption spectrometry (ETAAS) were employed to determine the toxic elements in fourteen fruits harvested in Pakistan. As, Br, Hg, Sb and Se were determined using INAA. Cadmium and Pb were determined using ETAAS. The intake levels of all toxic elements have been calculated. The data show that dates supply the maximum amount of most of the toxic elements. Peels of apple and pear have also been investigated and were found to contain higher concentration of toxic elements than their edible parts. The reliability of the techniques has been established by the use of standard reference materials. This study shows that all investigated fruits cultivated and consumed in Pakistan are safe for human consumption.     

Heavy metal determinations in algae and clams and their possible employment for assessing the sea water quality criteria

An empirical criterion for a possible classification of sea water quality is proposed. It is based on the knowledge of metal content in algae (Ulva Rigida) and clams (Tapes Philippinarum), two species present in marine ecosystems. The elements considered are Hg, Cu, Pb, Cd, Zn. The analytical technique employed is Differential Pulse Anodic Stripping Voltammetry (DPASV) in the case of Cu, Pb, Cd, Zn, while the determination of mercury is obtained by the Cold Vapour Atomic Absorption Spectroscopy (CV-AAS) technique with SnCl2 as reducing agent. The analytical procedure has been verified on three standard reference materials: Sea Water BCR-CRM 403, Ulva Lactuca BCR-CRM 279 and Mussel Tissue BCR-CRM 278. For all the elements, in addition to detection limits, accuracy and precision are given: the former, expressed as relative error (e), and the latter, expressed as relative standard deviation (Sr), were in all cases lower than 6%.     

Vanadium biomonitoring by using <Emphasis Type="Italic">Perna perna</Emphasis> (Linnaeus, 1758) mussels transplanted in the coast of the State of São Paulo,Brazil

The increased pollution in the aquatic ecosystem has led to the investigation of toxic elements in sea water by using marine organisms to assess marine pollution from human activities. Among these organisms, the mollusks bivalves have been used as biomonitors since they can accumulate trace elements and other substances, without the occurrence of their death. In this study, Perna perna mussels were transplanted from a mussel farm (reference region) to four sites located in coastal regions of São Paulo State, Brazil, close to anthropic discharge areas. Vanadium was determined in mussel tissues by instrumental neutron activation analysis (INAA). Quality control of V analysis was checked by analyzing biological reference materials and the results obtained were precise and in good agreement with the certified values. Comparisons between the V concentrations obtained in transplanted mussels indicated that those from São Sebastião region, close to an oil terminal presented the highest concentration of this element, during spring.     

Toxic and essential metals determination in commercial seafood: Paracentrotus lividus by ICP-MS

Toxic and essential metals content was determined by inductively coupled plasma mass spectrometry in commercial sea urchins samples from the Mediterranean Sea and Pacific Ocean. Results show that Chilean samples have the highest values of Cd, As, Ni, Cr and V; Spanish samples have the maximum Hg content while Sicilian samples have the lowest content of toxic metals. The toxic metal traces were compared with the limits of European Community (EC) No. 1881/2006 for bivalve molluscs. All samples exceed Pb and Cd limit levels; regarding Hg levels, only Sicilian and Sardinian samples have Hg content below the EC limits. The dietary intake of toxic and essential elements was evaluated for an adult. Furthermore, our study highlights a correlation between the toxic elements content and the marine environmental conditions of the places of origin even though only the generic FAO fishing area is specified.     

Elemental analysis of traditional medicinal seeds by instrumental neutron activation analysis

Traditional medicinal seeds prescribed for specific treatment purposes, were purchased from local markets and analyzed by INAA. The samples were irradiated at Es-Salam research reactor, at a power of 5 MW for 6 h. The accuracy of the method was established by analyzing reference materials. Twenty elements were measured, with good accuracy and reproducibility. The concentration of elements determined, was found to vary depending on the seeds. The daily intake of essential and toxic elements was determined, and compared with the recommended values. The probable cumulative intake of toxic elements is well below the tolerance limits.     

Development of frozen whale blubber and liver reference materials for the measurement of organic and inorganic contaminants

Summary Fresh frozen homogenates of pilot whale blubber and liver tissue were prepared for use as control materials for the determination of organic and inorganic contaminants in marine mammal tissue analyses. The blubber material was analyzed to determine 30 polychlorinated biphenyl congeners and 16 chlorinated pesticides using gas chromatography with electron capture detection and gas chromatographymass spectrometry. A total of 39 trace elements and methylmercury were determined in the liver homogenate using instrumental neutron activation analysis, voltammetry, and cold vapor atomic absorption spectroscopy. The preparation and analysis of these two tissue materials are part of the development of marine mammal tissue reference materials.     

Non-destructive alpha-particle activation analysis of P,Cl, K and Ca in marine macro-alga samples using synthetic multielement reference material as comparative standard

A Synthetic Reference Material (SyRM) composed with accurately known amounts of 12 elements has been prepared. The elemental composition of the SyRM is closely similar to that of marine macro-algac sample. The elemental composition of the SyRM was regulated by the starting materials used for the synthesis. The SyRM was used as a comparative standard for non-destructive alpha-particle activation analysis of marine macro-alga samples. P, Cl, K and Ca were determined simultaneously without correction for alpha range due to difference in the elemental composition between the analytical samples and the comparative standard.     

应用多接收器电感耦合等离子体质谱法测定海洋碳酸盐中稳定铅同位素组成

研究了多接收器电感耦合等离子体质谱仪(MC-ICP MS)测定铅同位素比值时,影响测试结果准确度和精密度的主要因素及其优化过程。在优化条件下,10 h内连续30次测定4 ng/mL NIST SRM 981同位素标准溶液铅同位素比值,获得208Pb/206Pb、207Pb/206Pb和206Pb/204Pb相对标准偏差(RSDs)分别为0.005%、0.004%和0.054%。长期监测208Pb/206Pb、207Pb/206Pb和206Pb/204Pb,标准偏差(2SDs)分别为0.000 06、0.000 05和0.006 7。采用NEPTUNE MC-ICP MS法测定了低铅海洋碳酸盐样品中稳定铅的同位素比值,并对南海橙黄滨珊瑚(Porites lutea)和库氏砗磲(Tridacna gigas)进行了分析,得到全流程空白为8～10 pg,重复样误差优于0.1%。经0.50 mol/L HNO3洗脱之后,得到海南珊瑚样品中208Pb/206Pb、207Pb/206Pb的比值分别为2.086 2±0.001 5、0.849 90±0.001 47(n=16);海南砗磲样品中208Pb/206Pb、207Pb/206Pb的比值分别为2.116 9±0.004 2、0.864 81±0.001 62(n=9)。进一步考察了南海海洋碳酸盐中204Pb的同位素比值。分析结果表明,南海海洋碳酸盐中稳定铅同位素比值与中国气溶胶、珠江三角洲大气沉降、黄土及南海海底玄武岩等具有很好的相关性。方法适用于复杂基体高钙低铅的海洋碳酸盐样品中铅同位素比值的分析。     

Distribution of <Superscript>137</Superscript>Cs activities in clams, <Emphasis Type="Italic">Tivela mactroidea</Emphasis> collected along the northern coast of Venezuela and the island of Margarita

Clam meats were obtained directly from the fishermen on the beaches in front of where the clams were collected at eight sites; seven along the northern coast of Venezuela and one on the northern coast of the island of Margarita (Venezuela). Marine sediments were also collected in the same corresponding areas as the clams. ¹³⁷Cs was determined both in clam meats and the marine sediments by high resolution gamma-ray spectrometry employing a hyperpure germanium detector. About 5 kg portions of clam meats were washed and dried in the laboratory, before 500 cm³ volumes were transferred and weighed in the measuring containers. Similarly, 500 cm³ volumes of marine sediments that were dried and ground to pass a 85 μm sieve were transferred to the measuring containers. The samples were counted for 150,000 seconds of real time. The ¹³⁷Cs activity of the clam meats ranged from <0.011 Bq·kg⁻¹ (our detection limit) to 0.36 Bq·kg⁻¹ (dried weigh). These values are all within the range of values considered for environmental fallout from the nuclear weapons tests. Finally, all the values for the corresponding marine sediments were below our detection limit of 0.1 Bq·kg⁻¹ of ¹³⁷Cs (dried weigh).     

Optimization of a centrifugation and ultrasound-assisted procedure for the determination of trace and major elements in marine invertebrates by ICP OES

A three factor Doehlert design was applied to optimize the extraction of elements in marine invertebrate samples (oyster, mussel and clam) using centrifugation with diluted acids. The factors were: concentration of acid mixture (HCl + HNO₃ + H₃CCOOH; 1–3 mol L^{− 1}), centrifugation time (10–40 min), and rotation velocity (6000–10,000 rpm). In order to evaluate the ultrasound effect on the extraction of trace metals, a portion of the certified oyster tissue sample (NIST 1556b; 0.250 g) was sonicated for 15 min and then the solution was centrifuged at the optimized conditions. The optimized procedure was then applied to nine marine invertebrate samples (oysters, clams and mussels) collected at Todos os Santos Bay, Bahia, Brazil. The optimized condition of the developed method was: 20 min of centrifugation at 9000 rpm using the acid mixture 1.0 mol L^{− 1}. The effect of sonication prior centrifugation was very variable, but it promoted a significant increase in the extraction (12 to 44%) of some trace elements. Moreover, the combination of the centrifugation with sonication offered other advantages, such as improvement of the precision and accuracy, both demonstrated using the oyster tissue reference sample. The results of major and trace elements in marine invertebrate samples showed that elements such us Cd and Cu in oyster samples and Zn in mussel and clam samples were above recommendations, suggesting that its consumption may impose health risks.     

Neutron activation analysis of Urartian pottery from eastern Anatolia

The assessment of environmental pollution of the coastal areas of the Malaysian Peninsula was done by analyzing the contents of the heavy and trace elements in the bivalves blood clams (Anadara granosa) and green mussels (Perna viridis) and sediments at twenty-two sampling stations to look for prevailing trends. Heavy and trace elements analyzed in this study were As, Cd, Cr, Cu, Pb, Se and Zn. Two techniques, namely the neutron activation analysis (NAA) and atomic absorption spectrophotometry (AAS) were used in the quantitative determination of the heavy metals while Marine Sediment Reference Material (BCSS) and Lobster Hepatopancreas (TORT-1) provided the certified reference materials in the quality assurance control. The potential use of these bivalves as suitable bio-indicators was evaluated from correlation tests based on the concentrations of heavy and trace elements in the sediment-metals system to those in the bivalves.     

Certified sediment reference materials for trace element analysis from the National Metrology Institute of Japan (NMIJ)

Two types of sediment reference material (NMIJ 7302-a and 7303-a) for trace elements analysis have been prepared and certified by the National Metrology Institute of Japan in the National Institute of Advanced Industrial Science and Technology (NMIJ/AIST). The original materials were collected from a bay near industrial activity in Kyushu (NMIJ CRM 7302-a; marine sediment) and from Lake Biwa (NMIJ CRM 7303-a; lake sediment). The sediment materials were air-dried, sieved, homogenized, packaged in 1000 glass bottles (60 g each), and radiation sterilized. Certification of these CRM for trace elements was conducted by NMIJ, where each element was determined by at least two independent analytical techniques. Isotope-dilution inductively coupled plasma mass spectrometry (ICP–MS) was applied for certification of all the elements except mono-nuclide elements such as As and Co. Other techniques such as ICP–MS with quadrupole mass spectrometry and sector-field mass spectrometry, inductively coupled plasma atomic emission spectrometry (ICP–AES), and atomic absorption spectrometry (AAS), were also used. Certified values have been provided for 14 elements (Sb, As, Cd, Cr, Co, Cu, Pb, Hg, Mo, Ni, Se, Ag, Sn, and Zn) in both CRM.     

Identification of the novel thio-arsenosugars DMThioAsSugarCarboxyl, DMThioAsSugarCarbamate and DMThioAsSugarAdenine in extracts of giant clam tissues by high-performance liquid chromatography online with electrospray tandem mass spectrometry

Recently, the identification of four thio-arsenosugars in extracts of marine samples was reported. The biosynthesis of these arsenic species is most likely closely related to the well known oxo-arsenosugars. Due to their symbiotic algae giant clams contain oxo-arsenosugars with Carboxyl-, Carbamate- and Adenine-aglycone in significant amounts. Now we provide evidence for the presence of the thio analogues of these three arsenosugars in tissue extracts of the giant clams Tridacna maxima and Tridacna derasa. Anion-exchange high-performance liquid chromatography (HPLC) online with electrospray tandem mass spectrometry was applied for the identification of the thio-arsenosugars and the indirect quantification via their oxo analogues.     

Elemental concentrations in sediments of the Patras Harbour, Greece, using INAA, ICP-MS and AAS

Twenty marine sediment samples, selected downcore from six sediment cores, which were retrieved from the Patras Harbour, were studied for their elemental composition using three analytical techniques: INAA, ICP-MS and AAS. Standard reference materials were used to verify the accuracy of the analysis techniques. In total, the concentrations of 30 major, minor and trace elements were measured. The vertical distribution of most elements in the examined cores could be characterized as relatively uniform. The eastern part of the harbour seems to be more polluted in respect to some elements (Ag, Br, Cd, Cr, Cu, Pb and Zn) compared to the western one. The concentrations of a number of elements (As, Cd, Cr, Cu, Ni, Pb and Zn) determined in the sediment samples of the present work are discussed regarding to those obtained from other harbours in the world and compared against sediment quality guidelines (SQGs) to assess the ecotoxicological significance of the sediment contaminants to benthic biota.     

Analysis of marine samples by neutron-induced prompt gamma-ray technique and ICP-MS

Multi-element and isotopic analyses of oils and marine environmental samples were carried out to estimate a contamination source using a "finger printing" method. Elemental analyses were carried out using neutron-induced prompt gamma-ray analysis (PGA), instrumental neutron activation analysis (INAA) at the Japan Atomic Energy Research Institute, Tokai-mura, Japan (JAERI) and ICP-MS in the IAEA Marine Environment Laboratory, Monaco (MEL). Fifteen elements including light elements, H, B, N, Si and Ca, which cannot be determined by INAA and ICP-MS, were determined by PGA. A total of 47 elements were determined in the present study. The potential of PGA for the determination of isotopic ratios was tested by measuring ³⁴S/³²S ratios in oils. The evaluation of historical records of marine environmental conditions using annual bands in coral samples was also investigated.     

Preparation and characterization of a suite of ephedra-containing standard reference materials

The National Institute of Standards and Technology, the U.S. Food and Drug Administration, Center for Drug Evaluation and Research and Center for Food Safety and Applied Nutrition, and the National Institutes of Health, Office of Dietary Supplements, are collaborating to produce a series of Standard Reference Materials (SRMs) for dietary supplements. A suite of ephedra materials is the first in the series, and this paper describes the acquisition, preparation, and value assignment of these materials: SRMs 3240 Ephedra sinica Stapf Aerial Parts, 3241 E. sinica Stapf Native Extract, 3242 E. sinica Stapf Commercial Extract, 3243 Ephedra-Containing Solid Oral Dosage Form, and 3244 Ephedra-Containing Protein Powder. Values are assigned for ephedrine alkaloids and toxic elements in all 5 materials. Values are assigned for other analytes (e.g., caffeine, nutrient elements, proximates, etc.) in some of the materials, as appropriate. Materials in this suite of SRMs are intended for use as primary control materials when values are assigned to in-house (secondary) control materials and for validation of analytical methods for the measurement of alkaloids, toxic elements, and, in the case of SRM 3244, nutrients in similar materials.     

CRMs for quality control of determinations of chemical forms of elements in support to EU legislation

The concern for the control of toxic chemical forms of elements in the environment is reflected by an increasing number of analyses performed by research and routine laboratories. The European Commission has recognised the need to include some of these species in the list of dangerous substances to be monitored, e.g. in the marine environment or in groundwater. However, in most cases, the specifications are far from being sufficient in respect to the chemical forms of the element to be determined. Furthermore, these determinations are in most cases based on multi-step analytical techniques which are often prone to errors (e.g. at the extraction, derivatization or separation steps). Certified reference materials (CRMs) certified for their content in chemical forms of elements are, therefore, necessary to ensure the accuracy of these measurements and hence the respect of the regulations. However, the lack of CRMs for speciation analysis hampers the quality control of determinations which in turn leads to an incomparability of data produced; so far the number of CRMs produced by international organisations, e.g. NIST (USA), NIES (Japan), NRCC (Canada) and BCR (Belgium), is very limited and concerns mainly compounds such as e.g. methyl-mercury and butyltin compounds in biological matrices or sediments. The Standards, Measurements and Testing Programme (formerly BCR) of the European Commission has started a series of projects for the improvement of speciation analysis in environmental matrices, the final aim of which being the production of a variety of environmental CRMs. The existing EU legislation involving chemical forms of elements is presented, the requirements for the preparation of CRMs for speciation analysis are discussed and an update of the most recent CRMs produced within the Standards, Measurements and Testing Programme (SM&T) is given.