Chemometric studies of some trace elements in cows' milk

The matrix of the correlation between the concentrations of 11 trace elements determined in 45 samples of cows' milk was used as a starting matrix for principal component analysis. The space dimension was reduced from 11 variables to 5 principal components, accounting for about 80% of the total variance. After an orthogonal rotation, the first factor (F1) was found to be positively correlated with Cr, Mn, and Fe, F2 positively correlated with Ni and negatively with Cu, F3 positively with Cd and Pb, F4 positively with Zn, Sr, and Mo and F5 positively correlated with A1 and Sr. Element clusters appear to be determined by their origin. Some clusters are confirmed by principal factor analysis. A plot of the principal component scores was also applied to the differentiation of Italian Milk from different geographical origins.     

Investigation of trace element content of cheese

Nine trace elements (Al, Cr, Mn, Fe, Ni, Cu, Zn, Cd, Pb) were determined in cheese by atomic absorption spectrophotometry with electrothermal atomization in a graphite tube, using the ashing procedure. Associations among mineral constituents were studied by means of principal component analysis, which allows determination of interdependences among trace elements in foods. A test for normality was used to investigate monovariate distributions, in order to estimate the symmetry of data vector. The correlation matrix was used as a starting matrix for principal component analysis; nine variables were reduced to four principal components. The clusters of elements appear to be determined by their origin.     

Chemometric studies of some trace elements in cows' milk

Summary The matrix of the correlation between the concentrations of 11 trace elements determined in 45 samples of cows' milk was used as a starting matrix for principal component analysis. The space dimension was reduced from 11 variables to 5 principal components, accounting for about 80% of the total variance. After an orthogonal rotation, the first factor (F1) was found to be positively correlated with Cr, Mn, and Fe, F2 positively correlated with Ni and negatively with Cu, F3 positively with Cd and Pb, F4 positively with Zn, Sr, and Mo and F5 positively correlated with Al and Sr. Element clusters appear to be determined by their origin. Some clusters are confirmed by principal factor analysis. A plot of the principal component scores was also applied to the differentiation of Italian Milk from different geographical origins.

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Chemometrische Untersuchungen über einige Spurenelemente in pasteurisierter Kuhmilch

Zusammenfassung Die Analyse der Hauptkomponenten wurde auf die Korrelationsmatrix zwischen Konzentrationen von 11 Spurenelementen in 45 Kuhmilchproben angewandt. Die Raumdimension von 11 Variablen wurde auf 5 Hauptkomponenten die 80% der totalen Varianz ausmachen, reduziert. Die orthogonal-rotierte Faktorenmatrix zeigt, daß Cr, Mn und Fe an die erste Hauptkomponente gebunden sind, Ni und Cu an die zweite, Cd und Pb an die dritte, Zn, Sr und Mo an die vierte and Al and Sr an die fünfte. Die Herkunft der Gruppen von Spurenelementen werden diskutiert. Einige Gruppen wurden bei der Analyse der Hauptfaktoren bestatigt. Das Diagramm der Hauptkomponentenwerte wurde auf die Unterscheidung von Milch aus zwei geographischen Herkünften angewandt.

     

Principal component analysis for the identification of pollution sources in mussel survey by trace metals

Principal component analysis has been applied to analyze the correlation matrix obtained from a 8 X 43 data matrix. The 8 trace metals are Mn, Co, Ni, Cu, Zn, Cd, Hg, Pb, which are contained in the soft part of mussels (Mytilus galloprovincialis Lamarck). Mussels were sampled from two sites in the Gulf of Trieste. In both samples, 76-78% of the total variance is explained by the four principal components. The orthogonally rotated factor matrix indicates that Co and Ni are bonded to the first principal component and Cd and Pb to the first (site 2) or second principal component (site 1). The origin of trace metals in the soft part of mussels from the Gulf of Trieste is discussed.     

Multivariate data analysis of sea waters and mussels in relation to pollution sources of trace elements

The total concentration of Cu, Zn and Pb in surface sea waters from the Bay of Muggia (Gulf of Trieste, Northern Adriatic Sea) was determined by anodic stripping voltammetry. The association of these trace elements in relation to the known sources of pollution was discussed. The content of eight trace elements (Mn, Co, Ni, Cu, Zn, Cd, Hg, Pb) in the soft part of mussels (Mytilus galloprovincialis Lamarck) is also considered. The wild molluscs were sampled in the harbour of Trieste, in the proximity of an important city sewer. Principal component analysis was used to analyse the correlation matrix obtained from an 8 x 43 data matrix after a logarithmic transformation of the concentration variables. Eight variables were reduced to four principal components, which explained 80% of the total variance. The orthogonally rotated factor matrix shows that Co, Ni, Cd, and Pb are associated with the first principal component, Cu and Zn to the second, Hg to the third and Mn to the fourth principal component. The results of this multivariate data analysis are compared with those already obtained from two sampling sites in the Bay of Muggia and the origin of some trace metals in the soft part of mussels from the Gulf of Trieste is discussed.     

A survey of selected essential and heavy metals in milk from different regions of Egypt using ICP-AES

The aim of this paper was to assess the content of selected essential metals (Fe, Zn, Cu and Cr) and some heavy metals (Pb and Cd) in raw cow's milk collected from different Egyptian areas during different periods of one year (January–February, May–June and September–October 2009). Twenty-one samples of raw milk were analysed using inductively coupled plasma–atomic emission spectrometry for quantitative determination. The highest metal accumulation levels for Cd, Cr, Fe and Cu are found in milk samples collected from Shubra, while samples from Menofia and Tanash are high in Pb and Zn, respectively. On the other hand, the highest metal accumulation levels were during January–February for Cd, Cr and Zn. In the period of May–June, the content of Pb, Cu and Fe were the highest, while the samples during the September–October period are characterised by the lowest metal content.     

电感耦合等离子体质谱法同时检测贵州省芸豆中13种元素含量

目的 建立电感耦合等离子体质谱法(inductively coupled plasma mass spectrometry,ICP-MS)同时测定贵州芸豆主产地28份芸豆样品中Na、Mg、P、Ca、Cr、Mn、Fe、Cu、Zn、As、Cd、Hg、Pb 13种元素的定量分析方法.方法 采用主成分分析和聚类分析方法分析贵州...     

基于矿物元素分析对进口泰国、越南、柬埔寨香米产地的鉴定

目的 探讨泰国、越南、柬埔寨3国香米矿物元素含量差异,并对产地进行鉴别。方法 通过电感耦合等离子体质谱法(inductively coupled plasma mass spectrometry, ICP-MS)测定泰国、越南、柬埔寨3国75份香米中Cr、Ni、Cu、Zn、As、Se、Cd、Hg和Pb 9种矿物元素含量,对测定结果进行差异性分析、相关性分析、主成分分析和Fisher判别。结果 所有样本均未检出Pb,其中Ni、Cu、Zn、As、Se、Cd6种元素在不同国家之间有显著性差异(P<0.05),并且Cu在3个国家之间均存在极显著差异(P<0.01),6种元素相互之间存在一定的相关性。主成分分析中选取了前2个主成分,累计方差贡献率为71.334%。确定Cu、Ni和Se元素是造成不同产地香米矿质元素差异的特征因素。通过Fisher判别建立溯源模型,对越南训练集和验证集判别准确率为100%,而对柬埔寨和泰国的训练集判别准确率达到70%以上,验证集的判别准确率达到80%以上。结论 通过Fisher判别法可较为有效地鉴别泰国、越南、柬埔寨3个国家的香米。     

Multivariate data analysis of sea waters and mussels in relation to pollution sources of trace elements

Summary The total concentration of Cu, Zn and Pb in surface sea waters from the Bay of Muggia (Gulf of Trieste, Northern Adriatic Sea) was determined by anodic stripping voltammetry. The association of these trace elements in relation to the known sources of pollution was discussed. The content of eight trace elements (Mn, Co, Ni, Cu, Zn, Cd, Hg, Pb) in the soft part of mussels (Mytilus galloprovincialis Lamarck) is also considered. The wild molluscs were sampled in the harbour of Trieste, in the proximity of an important city sewer. Principal component analysis was used to analyse the correlation matrix obtained from an 8 × 43 data matrix after a logarithmic transformation of the concentration variables. Eight variables were reduced to four principal components, which explained 80% of the total variance. The orthogonally rotated factor matrix shows that Co, Ni, Cd, and Pb are associated with the first principal component, Cu and Zn to the second, Hg to the third and Mn to the fourth principal component. The results of this multi-variate data analysis are compared with those already obtained from two sampling sites in the Bay of Muggia and the origin of some trace metals in the soft part of mussels from the Gulf of Trieste is discussed.

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Mehrdimensionale Analyse der Daten von Seewasser und Muscheln in Beziehung zu Verunreinigungen mit Spurenelementen

Zusammenfassung Der Gesamtgehalt von Cu, Zn, Pb in den oberen Schichten des Seewassers aus der Bucht von Muggia (Golf von Triest) wurde nach einer puls-inversvoltammetrischen Methode untersucht. Es wurden die Beziehungen dieser Spurenelemente zu den bekannten Verunreinigungsursachen diskutiert. Weiterhin wurde der Gehalt von Mn, Co, Ni, Cu, Zn, Cd, Hg, Pb im Fleisch von Miesmuscheln (Mytilus galloprovincialis Lamarck) untersucht. Die Mollusken stammen aus der Umgebung des Hafens von Triest, in der Nähe eines wichtigen Abwasserkanals. Die Korrelationsmatrix geht aus der 8 × 43-Datenmatrix nach einer logarithmischen Transformation der Konzentrationsvariablen hervor, dies basiert auf der Analyse der Hauptkomponenten. 8 Variable wurden auf 4 Hauptkomponenten, die 80% der totalen Varianz erklären, reduziert. Die orthogonal-rotierte Faktorenmatrix zeigt, daß Co, Ni, Cd und Pb an die erste Hauptkomponente, Cu und Zn an die zweite, Hg an die dritte und Mn an die vierte Hauptkomponente gebunden sind. Die Ergebnisse dieser Forschung werden mit denen vorhergehender mehrdimensionaler Analysen aus zwei Gegenden in der Bucht von Muggia verglichen. Die Herkunft der Spurenelemente im Muschelfleisch aus dem Golf von Triest werden diskutiert.

     

浓香型白酒蒸馏过程中金属元素的迁移变化规律

利用微波消解结合电感耦合等离子体质谱检测的方法测定泸州老窖浓香型白酒蒸馏过程中,蒸馏前后的酒糟、底锅水及所得的酒样样品中Na、K、As、Pb、Cd、Sn、Ti、Mg、Fe、Cu、Mn、Zn、Ca、Al、Ni、Cr和Ba 17 种金属元素的含量,并借助SPSS统计学软件采用t检验分析酒体中对应元素的来源。结果表明,蒸馏之后超过94%的金属元素仍保留在糟醅中,不到6%的金属元素转移至白酒及底锅水中。Pb、Mn、Cr等重金属元素的转移率显著低于Na、K、Ca和Mg等矿质元素,有效减少了酒中Pb、Mn、Cr等重金属的超标几率。酒样中的Ca、Cu、K、Mg、Na、Zn和Ba等元素主要来源于糟醅,而蒸馏使用的设备则会引入Fe、Ni、Al、Sn元素,Pb和Cr等有害重金属。     

Chemometric analysis of minerals and trace elements in raw cow milk from the community of Navarra,Spain

The concentrations of protein, fat, five minerals (Na, K, P, Ca and Mg) and nine trace elements (Fe, Zn, Cu, Mn, Se, Al, Cd, Cr and Pb) have been determined in 347 samples of raw cow milk from the community of Navarra, north Spain, using infrared analysis, atomic absorption spectrometry (flame and electrothermal atomisation) and inductively coupled plasma atomic emission spectroscopy. A preliminary chemometric study with the use of pattern recognition methods was carried out in order to characterise, classify and distinguish the different collected samples on the basis of their contents. Principal component analysis (PCA) has permitted the reduction of 16 variables to five principal components which interpret reasonably well the correlations of these studied variables. These variable associations may be attributed to intrinsic (lactogenesis) and other extrinsic factors, such as seasonal variation, animal feeding or geographical situation. Changes in these contents during different seasons were also assessed and consistently interpreted. Linear discriminant analysis (LDA) was used to explore cow milk samples, classifying according to season or geographical location, providing complementary information to PCA. This work shows that PCA and LDA are useful chemometric tools for the multivariate characterisation of raw cows’ milk.     

Determination of element contents in herbal drugs: Chemometric approach

The elemental content of 23 commercial herbal drugs was evaluated and multivariate analysis such as principal component analysis (PCA) and hierarchical cluster analysis (HCA) were performed with aim to know the relationship among the elements in the herbal drugs. Among the 13 elements investigated K (8096.97), Na (581.53), Cu (2.06); Mg (678.4); Fe (476.93), Al (321.5), Co (0.22); Zn (4.46), Ni (0.56); Mn (25.77); Pb (13.33); and Cr (13.18) mg/kg dry weight, respectively, were found at high concentrations in Eclipta prostrata; Adhatoda vasica; Phyllanthus amarus; Hybanthus enneaspermus; Cardiospermum halicacabum; Acacia nilotica; and Denolix elata. Interestingly, the toxic element Cd was below detectable level in all the samples and Cr, Pb and Ni were lower than the permissible limit as prescribed by the World Health Organisation (WHO). This study clearly shows that PCA and HCA procedures appear useful tools for the differentiation and classification of herbal drugs using the profile of elements.     

Heavy metal content in different types of smoked meat in Serbia

Concentrations of Fe, Cu, Ni, Cr, Pb, Mn, Zn and Cd in pork, beef, turkey and chicken samples were determined using inductively coupled plasma-optical emission spectrometry (ICP-OES). The mean concentration ranges in milligrams per 100?g of the studied metals in all samples were 0.6924–1.2154 for Fe, 0.6492–0.9831 for Cu, 0.0012–0.0027 for Pb, 0.041–0.0510 for Ni, 0.1186–0.1481 for Mn, 0.7257–5.2726 for Zn and 0.0042–0.0050 for Cd. The levels of analysed elements were in accordance with European standards for all metals except for manganese in all samples and for nickel in a certain number of samples. Zn level in beef was significantly higher compared to other samples, and Pb and Cd were found in concentrations well below the recommended daily intake.     

Elemental Composition of Various Sour Cherry and Table Grape Cultivars Using Inductively Coupled Plasma Atomic Emission Spectrometry Method (ICP-OES)

Three sour cherry and three table grape cultivars were analyzed using inductively coupled plasma optical emission spectrometry. The elements: Na, K, Ca, Mg, Fe, Cu, Zn, Mn, Cr, Cd, Co, Pb, and Ni were detected in all samples; four elements are very abundant (K, Na, Ca, and Mg), and four are not abundant (Cu, Fe, Mn, and Zn). Five of them are trace elements (Cr, Cd, Co, Pb, and Ni) at <0.1 mg/kg. Among the 13 elements analyzed, potassium was the most abundant element distributed throughout all categories of fruits. Iron was the predominant minor element constituents. Manganese concentration was the highest in table grape cultivars. The accuracy of the results was evaluated by spike recovery tests. Analysis of variance was used to establish the metals with significant difference in mean content between the cultivars from sour cherries and between table grapes. Principal component analysis was used to evaluate the distribution of metals.     

ICP-MS法测定可降解塑料制品中11种元素

可降解塑料制品样品采用硝酸、盐酸和过氧化氢,于220℃微波辅助加热消解,采用电感耦合等离子质谱(ICP-MS)法同时测定样品中锌、铜、镍、镉、铅、汞、铬、钼、硒、砷和钴11种元素含量。优化了碰撞气体流量、反应气流量等测试条件。结果显示,11种元素仪器检出限在0.0003~0.02 mg·kg^-1之间,7次重复性相对标准偏差(RSD)为1.1%~5.6%。在加标回收试验(汞元素0.3,0.5和0.7 mg·kg^-1,其余元素3.0,5.0和7.0 mg·kg^-1)中,其回收率为85.7%~105.9%。7批次外卖用可降解塑料制品样品中均有锌、铜、镍、铅和铬元素检出,部分样品中有钼、砷和钴元素检出,3批次样品铜元素含量超过标准限量。该方法检测限低、快速、准确,适用于可降解塑料制品中11种元素同时测定。     

Contribution to the study of avocado honeys by their mineral contents using inductively coupled plasma optical emission spectrometry

Avocado honey samples were analyzed by inductively coupled plasma optical emission spectrometric. First, the botanical origin of the honeys was confirmed by melissopalynological analysis. Twenty-four minerals were quantified for each honey sample. The elements Al, Ba, Ca, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Na, Ni, P, Pb, S, Se, Si and Zn were detected in all samples; seven elements were very abundant (Ca, K, Mg, Na, P, S and Si), six were not abundant (Al, Cu, Fe, Li and Zn) and 11 were trace elements (As, Ba, Cd, Co, Cr, Mo, Ni, Mo, Pb, Se, Sr and V).     

Rapid Determination of Trace Elements in Macedonian Grape Brandies for Their Characterization and Safety Evaluation

A graphite furnace atomic absorption spectrometry (GFAAS) was used for determination of trace elements (Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) in “rakija” samples, a grape brandy traditionally produced in Republic of Macedonia by distillation of grape pomace or wine, for characterization and safety evaluation. Cd, Pb, Cr, and Ni were determined directly, while Cu, Fe, Mn, and Zn were quantified after appropriate dilution. The calibration curves of all elements were linear with correlation coefficients (R ²) ranging from 0.9995 to 0.9998. The accuracy of the method was checked with a standard addition method showing good repeatability and reproducibility (relative standard deviation (RSD) <10 %). Relationship between several metal concentrations (Cu, Fe, Mn, Zn) in brandies and distillation system (homemade/industrial) on one side and aging mode (oak barrels/oak chips) on the other side were demonstrated. Two homemade brandies showed Cu, Fe, and Zn concentrations higher than industrial distillates and thus were found to be not safe for consumption because of Cu and Zn over the maximum allowed values. For the industrially produced brandies, Mn was identified to be a suitable marker related to aging with oak chips regardless variety, while Cu a marker for the influence of oak chip type. Principal component analysis applied on the content of elements clearly showed a good separation in terms of distillation and aging method.     

江西抚州烟区土壤及烟叶重金属污染状况评价

为了弄清江西抚州烟区土壤和烟叶中As、Cd、Cr、Cu、Ni、Pb、Zn和Hg等重金属含量和污染状况,运用内梅罗指数和相关分析法,对这些重金属元素在土壤和烟叶中的含量进行了测定。结果表明,该烟区土壤中重金属含量总体上低于我国土壤二级标准（GB15618-1995）,但其污染程度已处于警戒线水平,Cd和Hg为烟区土壤主要风险因子。土壤和烟叶中重金属含量顺序分别为Zn> Pb> Cr> Cu> Ni> As> Cd> Hg和Zn> Cu> Pb> Cd> Cr> Ni> As> Hg,土壤中Hg、Cd、As和烟叶中Ni、Cr变异系数均较大。烟叶中重金属富集系数顺序为Cd> Zn> Cu> Hg> Ni> Cr> Pb> As,烟叶Cd富集系数高达11.67,表明烟草属于Cd强烈富集作物。     

Principal component analysis for the identification of pollution sources in mussel survey by trace metals

Summary Principal component analysis has been applied to analyze the correlation matrix obtained from a 8 × 43 data matrix. The 8 trace metals are Mn, Co, Ni, Cu, Zn, Cd, Hg, Ph, which are contained in the soft part of mussels (Mytilus galloprovincialis Lamarck). Mussels were sampled from two sites in the Gulf of Trieste. In both samples, 76–78% of the total variance is explained by the four principal components. The orthogonally rotated factor matrix indicates that Co and Ni are bonded to the first principal component and Cd and Pb to the first (site 2) or second principal component (site 1). The origin of trace metals in the soft part of mussels from the Gulf of Trieste is discussed.

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Analyse der Hauptkomponenten zur Identifizierung der Verunreinigungsursachen von Muscheln über die Spurenmetalle

Zusammenfassung Die Analyse der Hauptkomponenten wurde auf die Korrelationsmatrix, die aus der 8 × 43-Datenmatrix hervorgeht, angewandt. Diese 8 Spurenmetalle sind Mn, Co, Ni, Cu, Zn, Cd, Hg, Pb, die im Fleisch der Miesmuscheln (Mytilus galloprovincialis Lamarck) gefunden worden sind. Die Miesmuscheln stammen aus zwei Gegenden des Golfes von Triest. Vier Hauptkomponenten erklären 76–78 % der totalen Varianz der beiden Stichproben. Die orthogonale-rotierte Faktorenmatrix zeigt, daß Co und Ni an die erste Hauptkomponente und Cd und Pb an die erste (Lage 2) oder an die zweite Hauptkomponente (Lage 1) gebunden sind. Die Herkunft der Spurenmetalle im Muschelfleisch aus dem Golf von Triest wird diskutiert.

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L. Felician is the author of the statistical analysis for site 1 as a part of his thesis in Commodity Science, Faculty of Economics, University of Trieste- L. Gabrielli Favretto is the author of the statistical analysis of the data for site 2. All authors contributed to the rest of the paper     

电感耦合等离子体原子发射光谱法测定不同产地山银花金属元素主成分及其聚类分析

采用电感耦合等离子体原子发射光谱仪,对全国7 个主要产地的26 个山银花样品中的10 种金属元素的 含量进行定量分析,应用主成分分析和聚类分析对山银花资源中金属元素进行评价。结果表明：Pb、As、Fe、 Ca、Zn、Mg、Mn、Cu、Cd、Cr的平均含量分别为0.25、0.065、77.9、3 277.1、31.0、2 244.7、319.9、14.6、 0.31、0.217 mg/kg;主成分分析得出3因子模型,可解释实验数据的88.58%;主成分分析将26 个山银花样品划分 为4 类,聚类分析显示了相似的结果。研究得出山银花中金属元素的含量分布特征,为山银花资源的品质评价和 质量控制提供实验依据。