Determination of Cu, Pb, Cd, Ni, Cr, Co, Mn, Fe and Zn in algae and vegetable samples using wet and dry ashing procedures

In this study, Cu, Pb, Cd, Ni, Cr, Co, Mn, Fe, and Zn metal levels of 9 vegetables (garlic, onion, radish, parsley, potato pod, cucumber, tomato, carrot, and pepper) from a local market in Kayseri, Turkey, and algae samples from the Aegean Sea, were determined by using FAAS. In the sample analyses, both wet and dry ashing methods were used. Dry ashing procedures employed involved combinations such as ashing time and being covered or uncovered of crucible. The results of seven dry and one wet ashing procedures used for the determination of elements in the samples were compared with each other. The comparison procedures were performed for cucumber, tomato, carrot and pepper samples. The correlations were satisfactory, except for Cu. and Mn. The heavy metal pollution for vegetable samples were also investigated. The elemental concentration ranges obtained with wet and dry ashing procedures for vegetable samples were as follows (mu g/g): 5.00 - 16.4, 6.18 - 14.0 or Cu., 2.82 - 6.49, 1.77 - 6.49 for Pb, 2.71 - 8.1, 1.50 - 7.98 forNi, 0.16 - 0.99,0.70 - 2.75 for Cr, 1.64 - 4.34, 0.80 - 4.48 for Co, 6.10 - 61.9, 6.22 - 67.8 for Mn, 16.2 - 199, 13.1 - 450 for Fe, 9.26 - 40.7, 14.7 - 45.8 for Zn, and 0.88 - 2.99, 0.20 - 2.50 for Cd, respectively

Relationship between vegetable metal and soil-extractable metal contents by the BCR sequential extraction procedure: Chemometrical interpretation of the data

The contents of heavy metals in soil and vegetable samples collected from an urban garden in Kayseri, Turkey, were investigated. Both wet- and dry-ashing methods were used for dissolving vegetable samples. A sequential extraction procedure proposed by the Commission of the European Communities, Community Bureau of Reference (now superseded by the Standards, Measurement and Testing Programme, SM&T) was applied to the soil samples to extract the metals which are present in exchangeable and acid soluble (i.e. bound to carbonates), reducible (bound to Fe/Mn oxides), and oxidisable forms (bound to organic matter and sulphides) in the soil samples. Trace metals in the soil and vegetable samples were determined using flame atomic absorption spectrometry (FAAS). The total metal contents acquired by summing of metal levels in all the sequential extraction steps were compared with pseudo-total metal levels obtained with aqua regia for all the soil samples. The recovery values obtained by proportioning the results obtained by the BCR procedure to those of the pseudo-total digestion were found to be satisfactory. The limits of detection for the elements investigated were in the range of 0.04 to 0.59 mug mL(-1) for all the extraction stages of the BCR procedure. Similarities among the variables were identified by correlation analysis, principal component analysis and hierarchical cluster analysis. The relationship between the vegetable metal and soil-extractable metal concentrations was examined in order to evaluate the bioavailability of metals

Multivariate analysis of the data and speciation of heavy metals in street dust samples from the Organized Industrial District in Kayseri (Turkey)

The concentrations of metals (Cd, Co, Cr, Cu, Mn, Ni, Pb and Zn) in 29 dust samples collected from the streets of the Organized Industrial District (OID) in Kayseri (Turkey) were determined by flame atomic absorption spectrometry (FAAS). The modified three-step BCR sequential extraction procedure was used in order to evaluate mobility, availability and persistence of trace elements in street dust samples. Multivariate statistical analysis was applied to the obtained data. Three operationally defined fractions isolated using the BCR procedure were: acid extractable, reducible, and oxidizable. The mobility sequence based on the sum of the BCR sequential extraction stages was: Cd (93.3%) > Zn (83.8%) > Pb (77.2%) > Co (75.9%) > Mn (73.0%) > Ni (60.1%) > Cu (59.0%) > Cr (58.6%). Correlation analysis, principal component analysis (PCA) and cluster analysis (CA) were applied to the data matrix to evaluate the analytical results and to identify the possible pollution sources of metals. PCA revealed that the sampling area was mainly influenced from three sources, namely industrial, traffic and natural sources. Validation of the analytical results was checked by analysis of the BCR-701 certified reference material. (c) 2006 Elsevier Ltd. All rights reserved

Comparison of three sequential extraction procedures for partitioning of heavy metals in car park dusts

The aim of this study was to elucidate the amount of metal released at each step by using different extractants in three sequential extraction schemes for the partitioning of metal contents of car park deposited dust samples. For this purpose, three different sequential extraction procedures ( SEP) were employed for the metal fractionation in car park dust samples collected from the campus of Erciyes University, Kayseri, Turkey. While two of the sequential extraction procedures contain five steps the other, namely the BCR sequential extraction scheme, has three steps. The first two methods fractionate metals to be exchangeable, bound to carbonates, bound to Mn oxides, bound to Fe oxides and bound to organic matter, and the BCR protocol fractionates the metals as acid soluble and exchangeable, reducible, and oxidisable. Determination of the metals Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn was performed by flame atomic absorption spectrometry (FAAS). The results obtained by the three methods were compared and showed that the amount of metal released at each step of the leaching procedure depended both on the type of reagents used and the sequence in which they were applied. The most mobile elements were Cd, Pb and Zn which are metals potentially toxic to the environment and are also known to originate from traffic. The calculated enrichment factors for Cd and Pb were substantially high (73.5 - 187 and 18.4 - 27.5, respectively) and somewhat lower for Zn (5.1 - 6.8). These results confirm that they are important metal pollutants for car parks. Detection limits and recoveries were found in the range of 0.01 - 1.39 mug ml(-1) and 68 - 126%, respectively, for the metals studied and the three sequential extraction procedures