Determination of Zn,Cu, Cd,Pb, Ni and Cr in some Slovenian foodstuffs

An acid-assisted microwave digestion procedure was optimised for the determination of trace elements in foodstuffs by the use of flame and electrothermal atomic absorption spectrometric (FAAS, ETAAS) techniques. Zn, Cu, Cd, Pb, Ni and Cr were determined in cabbage, wheat, potato, instant milk, fish, eggs and baby foodstuffs. The repeatability of measurements was tested in the cabbage sample and was found to be ±3.3% for Zn, 4.6% for Cd, ±6.8% for Cu and ±15.5% for Cr. The worse value obtained for Cr was probably due to its inhomogeneous distribution and very low concentration in the cabbage. Concentrations of Ni and Pb in the cabbage sample were below the limit of detection (0.2 mg kg^–1). The accuracy of the analytical procedure was checked by the analysis of the standard reference material CRM 1570 Trace and minor elements in spinach leaves and IAEA 336 Trace and minor elements in lichen. Good agreement between the certified or indicative and determined values was obtained. The results indicate that the concentrations of Zn, Cu, Cd, Pb, Ni and Cr found in cabbage, wheat and potato are comparable to the literature data. Cd, Pb and Ni were not found to be the contaminants in the foodstuffs analysed. Higher concentrations of Ni were found only in baby food "okolenik", arising from the cocoa that "okolenik" contained. It was demonstrated that the Cr content is very low in baby food, yolk and white of egg and in fish (<0.05 mg kg^–1 Cr). Elevated concentrations of trace elements were found only in mussels that accumulate heavy metals from the marine environment.     

Accumulation of Cu, Pb, Ni and Zn in the halophyte plant Atriplex grown on polluted soil

BACKGROUND: Three annual Atriplex species—A. hortensis var. purpurea, A. hortensis var. rubra and A. rosea—growing on soil with various levels of the heavy metals copper, lead, nickel, and zinc, have been investigated. RESULTS: Metal accumulation by Atriplex plants differed among species, levels of polluted soil and tissues. Metals accumulated by Atriplex were mostly distributed in root tissues, suggesting that an exclusion strategy for metal tolerance widely exists in them. The increased concentration of heavy metals in soil led to increases in heavy metal shoot and root concentrations of Ni, Cu, Pb and Zn in plants as compared to those grown on unpolluted soil. Accumulation was higher in roots than shoots for all the heavy metals. None of the plants were suitable for phytoextraction because no hyperaccumulator was identified. However, plants with a high bioconcentration factor and low translocation factor have the potential for phytostabilization. Similarly, the correlation between metal concentrations and translocations in plants (BCFs and TFs) using a linear regression was also statistically significant. CONCLUSION: Among the plants studied, var. purpurea was the most efficient in accumulating Pb and Zn in its shoots, whereas var. rubra was most suitable for phytostabilization of sites contaminated with Cu and Ni. Copyright © 2011 Society of Chemical Industry     

Determination of Cd,Co, Cu,Fe, Pb,Mn, Ni and Zn in diets: Development of a method

A method useful for the determination of cadmium, cobalt, copper, iron, lead, manganese, nickel and zinc in diets is described. Organic matter is destroyed applying a wet procedure, and element content is measured by flame atomic absorption spectroscopy (FAAS) in the case of copper, iron, manganese, nickel and zinc, and by graphite furnace (GF-AAS) in the case of cadmium, cobalt and lead. The matrix interference study is carried out. Values found for linearity, detection and quantitation limits as well as accuracy show that the described method is useful to determine the elements taken into account at usual levels in diets.     

Determination of Cd, Co, Cu, Fe, Pb, Mn, Ni and Zn in diets: development of a method.

A method useful for the determination of cadmium, cobalt, copper, iron, lead, manganese, nickel and zinc in diets is described. Organic matter is destroyed applying a wet procedure, and element content is measured by flame atomic absorption spectroscopy (FAAS) in the case of copper, iron, manganese, nickel and zinc, and by graphite furnace (GF-AAS) in the case of cadmium, cobalt and lead. The matrix interference study is carried out. Values found for linearity, detection and quantitation limits as well as accuracy show that the described method is useful to determine the elements taken into account at usual levels in diets.     

Deriving soil critical limits for Cu, Zn, Cd, and Pb: a method based on free ion concentrations

We present a method to calculate critical limits of cationic heavy metals accounting for variations in soil chemistry. We assume the free metal ion concentration (Mfree) to be the most appropriate indicator of toxicity, combined with a protective effect of soil cations (e.g., H+, Ca2+). Because soil metal cations tend to covary with pH, the concentration of Mfree exerting a given level of toxic effect (Mfree,toxic) can be expressed as a function of pH alone. We use linear regression equations to derive Mfree,toxic in toxicity experiments from soil pH, organic matter content, and endpoint soil metal. Chronic toxicity data from the literature, for plants, invertebrates, microbial processes, and fungi are interpreted in terms of an average log Mfree,toxic together with distributions of species sensitivity. This leads to critical limit functions to protect 95% of species, of the form log Mfree,CRIT = (pH + gamma. Appreciable effects of soil pH upon log Mfree,CRIT are found, with alpha = -1.21 (Cu), -0.34 (Zn), -0.43 (Cd), and -0.83 (Pb). Critical limit functions in terms of the geochemically active soil metal (Msoil,CRIT), that pool of metal which controls the free ion concentration, have also been derived, with soil pH and organic matter content as variables. The pH effect on Msoil,CRIT is relatively small, with slopes of 0.05 (Cu), 0.19 (Zn), 0.16 (Cd), and 0.20 (Pb), since the effect of pH on Mfree,CRIT is countered by the variation of Mfree with pH.     

Gehalt an Schwermetallen (Cd, Cu, Hg, Ni, Pb, Zn) in Bachforellen im Leine-Raum G?ttingen

Zusammenfassung Um das Ausmaß der Belastung der Leine mit Schwermetallen (Cd, Cu, Hg, Ni, Pb, Zn) durch die Abwässer der Stadt Göttingen zu erforschen, wurden die Schwermetallgehalte in Bachforellen, die der Leine an zwei Probenahmestellen, oberhalb bzw. unterhalb Göttingen (Abb. 1) entnommen worden waren, mit Hilfe des Atom-Absorptions-Spektrometer ermittelt.Die durchgeführten Schwermetalluntersuchungen (im Gesamtfisch, Muskulatur und Leber) ergaben im Vergleich der obengenannten Fangorte eine statistisch gesicherte Zunahme einiger Schwermetalle durch die in diesem urbanisierten Raum anfallenden Abwässer. In der Fischmuskulatur waren nur Cd, in der Leber Cd, Hg, Zn und im Gesamtfisch Cd, Cu, Zn signifikant erhöht.Sämtliche Schwermetallwerte der Fischmuskulatur lagen unterhalb der in der Literatur vorgeschlagenen, als zulässig zu betrachtenden Höchstwerte.

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The levels of heavy metals (Cd, Cu, Hg, Ni, Ph, Zn) in brook trouts from the River Leine in the area of Göttingen (West Germany)

Summary In order to evaluate the load of heavy metals (Cd, Cu, Hg, Ni, Pb, Zn) imposed on the River Leine by the city of Göttingen (medium-sized town) the content of heavy metals in fish samples (which had been collected at two points on the River Leine, upstream, respectively downstream of Göttingen — Fig. 1) were determined by Atomic Absorption Spectroscopy. Analysis of heavy metals in brook trout (total fish, flesh, and liver) showed a statistically significant definite increase in some heavy metals, caused by the sewage from the city of Göttingen. In the flesh only Cd in the liver Cd, Hg and Zn and in the total fish Cd, Cu and Zn had been increased significantly. All the values of heavy metals in the flesh were lower than the suggested maximum allowable concentrations.

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Diese Arbeit wurde am Institut für Agrikulturchemie der Universität Göttingen (Direktor: Prof. Dr. E. Welte) angefertigt     

原子吸收光谱法测定蔬菜中的锌、钙、铜、铅和镉

采用硝酸-高氯酸消解蔬菜样品,火焰原子吸收光谱法测定蔬菜中锌、钙和铜,石墨炉原子吸收光谱法测定蔬菜中的铅和镉。在最佳实验条件下对小白菜、香菜、西红柿和水萝卜4种蔬菜进行测定,含量分别为锌:90.333、74.417、54.417、76.667 mg/kg,钙:2.820 2、0.273 9、9.074 3、8.167 9 mg/kg,铜:11.618、22.768、8.618、14.844 mg/kg,铅:0.145 9、0.000 0、0.393 0、0.000 0 mg/kg和镉:0.687 1、0.360 6、0.058 0、0.626 0 mg/kg。加标回收率为98.15%~101.96%。     

Heavy metals (Pb,Cu, Zn and Cd) in the system soil – grapevine – grape

An Erratum has been published for this article in Journal of the Science of Food and Agriculture 79(15)1999, 2122. The investigation was carried out in the period 1991–1995 in a region with a major industrial pollutant, the Non‐Ferrous‐Metal Works, and a region with no industrial pollutants (as a control). The heavy metal content in soil, roots, annual shoots and perennial parts of grapevine, leaves, grapes and wine, was determined. Soil samples and roots of the rootstock Kober 5BB were taken at 10 cm intervals from depths of 0–100 cm. Roots were divided by thickness in fractions at 1 mm intervals. The shoots, bark, vascular tissue, wood, core and diaphragm were investigated. The leaf analyses included leaf blade and leaf petioles, and those of grapes, berry‐free raceme (washed in a lot of water and unwashed). Berries were analysed (the berry skin, the pulp and the seeds). The results obtained for the Pb, Cu, Zn and Cd contents in the grapevine roots show that they depend significantly both on their amounts in the soil and the age of the roots. The main parts of the heavy metal amounts taken by the roots of the grapevine from the soil are fixed and accumulated in the young feed rootlets (with diameters of 1 mm), and small amounts of them move through the conducting system to the older, larger diameter root system. The experimental data obtained for the presence of Pb, Cu, Zn and Cd in the separate tissues and organs of grapevines grown in an industrially polluted region showed that their amounts were mainly due to the heavy‐metal‐containing aerosols falling from the atmosphere. Part of them, however, got into the soil, and from there, even if in minimal amounts, penetrated via the root system into the grapevine plants and accumulated into their different overground parts. © 1999 Society of Chemical Industry     

The effect of storage of canned meat on concentration of the metals Fe, Cu, Zn, Pb, Sn, Al, Cd and Ni

Storage of canned foods may enrich the concentration of some metals. Because their toxic and other properties the presence of which in foods over certain limits is undesirable. Therefore we have determined the contents of Fe, Cu, Zn, Pb, Sn, Al, Cd and Ni over a 2 years' time of bovine, pork and veal meat. The results show a gradual increase in the concentration of Fe, Cu, Sn and Zn with time in the order pork greater than bovine greater than veal.     

The effect of storage of canned vegetables on concentration of the metals Fe, Cu, Zn, Pb, Sn, Al, Cd and Ni

The increase in the concentration of Fe, Cu, Zn, Pb, Sn, Al, Cd and Ni over a 2 year's time of strongly corrosive acidic vegetables (pickles) and weakly corrosive vegetables (peas, green beans, haricot beans, mushrooms) has been determined. The results show a considerable increase in Fe, Cu, Pb and Sn content with time, particularly for pickles, while the change in Al, Cd, Zn and Ni content was rather negligible.     

微波消解-火焰原子吸收光谱法测定百里香中微量元素

采用微波消解-火焰原子吸收光谱法(FAAS法),连续测定雷山县乌东村的百里香中的Zn,Fe,Cu,Mn,Ni,Cd,Cr,Pb含量。待测元素的最佳测试条件经过正交试验设计优化组合确定。结果表明,供试样品中微量元素Zn,Fe,Cu,Mn的含量分别为154.6,331.4,1.86,342.6mg/kg,而重金属元素Ni,Cd,Cr,Pb未检出。用此法节省时间和试剂,环境污染少,操作简便,精密度和准确度较高。     

Multielementary (Cd, Cu, Pb, Zn, Ni) Stable Isotopic Exchange Kinetic (SIEK) method to characterize polymetallic contaminations

A new method is proposed to precisely and simultaneously quantify the exchangeable pool of metals in soils and to describe its reactivity at short- and long-term. It is based on multielementary Stable Isotopic Exchange Kinetics (multi-SIEK), first validated by a comparison between two monoelementary radioactive ((109)Cd*, (65)Zn*) IEK experiments, a mono- ((106)Cd) and multi- ((62)Ni, (65)Cu, (67)Zn, (106)Cd, (204)Pb) SIEK. These experiments were performed on a polluted soil located near the Zn smelter plant of Viviez (Lot watershed, France). The IEK results obtained for Cd and Zn were consistent across the experiments. (109)Cd*, (65)Zn* IEK, and multi-SIEK were then applied on 3 non- and moderate impacted soils that also provided consistent results for Cd and Zn. Within these experimental conditions, it can be concluded that no competition occurs between Cd, Zn, and the other metals during SIEK. Multi-SIEK results indicate that the isotopically exchangeable pool of Ni, Zn, and Cu are small (E(Ni), E(Zn), and E(Cu) values up to 17%) whatever the pollution degree of the soils considered in this study and whatever the duration of the interaction. On the contrary, Cd displays the highest E values (from 35% to 61% after 1 week), and E(Pb) displays a maximum value of 26% after 1 week. The multi-SIEK provides useful information on metal sources and reactivity relationship. Ni would be located in stable pedogenic phases according to its very low enrichment factor. The low E(Zn) and E(Cu) are consistent with location of Zn and Cu in stable phases coming from tailings erosion. Though Pb enrichments in soils may also be attributed to tailings particles, its larger exchangeable pool suggests that the Pb-bearing phases are more labile than those containing Zn and Cu. The high mobility of Cd in upstream soils indicates that it has been mostly emitted as reactive atmospheric particles during high temperature ore-treatment.     

HEAVY METAL LEVELS IN VEGETABLES IN TURKEY ARE WITHIN SAFE LIMITS FOR Cu, Zn, Ni AND EXCEEDED FOR Cd AND Pb

Copper (Cu), cadmium (Cd), nickel (Ni), lead (Pb) and zinc (Zn) contents of various vegetables (cucumber, tomato, green pepper, lettuce, parsley, onion, bean, eggplant, peppermint, pumpkin and okra) produced in Kayseri, Turkey and the soils in which they were grown were determined using Inductively Coupled Plasma–Optical Emission Spectrometry (ICP–OES). These plants are the basis of human nutrition in the study area. The results obtained from the urban area were higher than those of the rural area as a result of pollution. The order of the elements in various vegetables and their concentration ranges in μg/g were Cu (22.19–76.5), Cd (0.24–0.97), Ni (0.44–13.45), Pb (3–10.7) and Zn (3.56–259.2). The concentrations of Cu, Zn and Ni in vegetables studied are within the recommended international standards. The results also show that onion (0.97 μg/g) and peppermint (76.5 μg/g) have the ability to accumulate more Cd and Cu than the other vegetables studied, respectively. Furthermore, there were statistically significant differences (P < 0.05) between the levels of Zn and Pb in all vegetables analyzed from urban and rural areas. Concentrations of metals analyzed in samples could be related to their concentration in the corresponding soils. Enhanced levels of metals observed in some vegetable species could be related to their concentration in the corresponding soils.     

The effect of storage of canned juices on content of the metals Fe, Cu, Zn, Pb, Sn, Al, Cd, Sb and Ni

The increase in concentration of iron, copper, zinc, lead, antimony, aluminium, cadmium, tin and nickel over a 2 year's time of juices of peach (prunus persica), pear (pyrus communis), apricot (prunus vulgaris) and apple (malus pumila) was determined. The results show a considerable increase in Fe, Cu, Pb, Zn and Sn with time, while the change in Al, Cd, Ni and Sb is negligible.     

A simplified method for the extraction of the metals Fe,Zn, Cu,Ni, Cd,Pb, Cr,Co and Mn from soils and sewage sludges

The method described for digestion of soil samples with aqua regia is simple, flexible and safe to operate with large sample throughout. At least nine metals can be determined in the resulting solutions with errors of <5%. The results compare favourably with those from reflux aqua regia and averaged 88% of the certified total values for reference soils and 88% of those for reference sewage sludges.     

Reaction-based model describing competitive sorption and transport of Cd, Zn, and Ni in an acidic soil

Predicting the mobility of heavy metals in soils requires models that accurately describe metal adsorption in the presence of competing cations. They should also be easily adjustable to specific soil materials and applicable in reactive transport codes. In this study, Cd adsorption to an acidic soil material was investigated over a wide concentration range (10(-8) to 10(-2) M CdCl2) in the presence of different background electrolytes (10(-4) to 10(-2) M CaCl2 or MgCl2 or 0.05 to 0.5 M NaCl). The adsorption experiments were conducted at pH values between 4.6 and 6.5 A reaction-based sorption model was developed using a combination of nonspecific cation exchange reactions and competitive sorption reactions to sites with high affinity for heavy metals. This combined cation exchange/specific sorption (CESS) model accurately described the entire Cd sorption data set. Coupled to a solute transport code, the model accurately predicted Cd breakthrough curves obtained in column transport experiments. The model was further extended to describe competitive sorption and transport of Cd, Zn, and Ni. At pH 4.6, both Zn and Ni exhibited similar sorption and transport behavior as observed for Cd. In all transport experiments conducted under acidic conditions, heavy metal adsorption was shown to be reversible and kinetic effects were negligible within time periods ranging from hours up to four weeks.     

Fractions affected and probabilistic risk assessment of Cu, Zn, Cd, and Pb in soils using the free ion approach

The free ion approach quantifies the toxic effects of cationic metals on soil biota as a function of chemistry. The approach is here extended to calculate the general relationship among toxic effects as the Fraction Affected (FA), soil solution pH, and soil organic matter content (SOM) for Cu, Zn, Cd, and Pb within toxicity data sets from literature. The dependence of FA on SOM is strong, with the FA decreasing as the SOM increases. The dependence of FA upon pH varies; Cd and Zn show strong dependences while for Cu and Pb dependences are weaker. The FA usually decreases as the soil pH increases. When the free ion approach is applied, risks across soils due to different metals can be compared using the FA. The free ion approach may also be applied to probabilistic risk assessment. Risk values, using the joint probability curve approach, were derived for Pb using two field soil data sets. One data set, with higher SOM than that of the Pb toxicity data set, gave a lower risk with the free ion approach than that when the soil chemistry was not considered. The other data set had lower SOM than that of the toxicity data set and gave a higher risk with the free ion approach. Since literature toxicity tests are biased toward low SOM soils of circumneutral pH, using such data to perform classical risk assessment for soils of differing chemical composition can lead to misestimation of risk due to neglecting soil chemistry, especially in soils with extreme pH and/or SOM.     

ICP-MS测定饼干中的铅、砷、铬、镉、铜、锌、铁和锰

探讨了应用电感耦合等离子体质谱仪测定饼干中铅、砷、铬、镉、铜、锌、铁和锰8种重金属元素的方法。运用微波消解系统对样品进行消解,以铋、锗、钪和铟作为内标物,用ICP-MS对消解液进行检测,并采用国标方法对其结果进行验证。利用加标回收率试验和国家标准物质小麦(GBW 10052)检测试验考察了方法的准确性和可靠性。结果表明,该方法所测元素在标准溶液浓度范围内呈线性关系,相关系数均大于0.999,方法检出限在0.002~0.500 mg/kg之间,相对标准偏差均小于6.55%,本法与国标方法测量结果的相对偏差在3.73%~8.40%之间,加标回收率在88.0%~106%之间,标准物质的测定值与标准参考值符合要求。     

Levels of Cu,Zn, Pb,and Cd in the leaves of the tea plant (Camellia sinensis) and in the soil of Gilan and Mazandaran farms of Iran

Tea is known as an inevitable and important part of a healthy and balanced diet. However, it might be contaminated by heavy metals via many ways, including irrigation by sewage water, industrial effluents, sewage sludge, vehicular emissions, industrial wastes, and atmospheric deposition. The concentrations of Cu, Zn, Cd, and Pb elements in the leaves and soil samples of the tea farms in North Iran were determined by using flame and graphite furnace atomic absorption spectrometry. The samples were digested with the concentrated nitric acid and perchloric acid. The descending sequence of the mean metal levels in the tea leaves is as follows: Zn > Cu > Pb > Cd. The content of heavy metals in the tea samples were found and are provided in the following ranges: 6.07–15.24, 55.35–127.22, 0.03–0.64, and 0.06–0.38 µg/g for Cu, Zn, Pb, and Cd, respectively. According to the Institute of Standards and Industrial Research of Iran (ISIRI), the tolerance limits have been adjusted only for copper, cadmium, and lead. However, the present database can be employed for fixing the tolerance limit of zinc in tea. The contents of copper and lead in tea were significantly lower than the permissible limit under the ISIRI act. In contrast, the cadmium concentration was significantly above the permissible limit (P < 0.05). In the conclusion, the comparisonis made between the research results and the literature values.