Trace elements in soil and coniferous needles.
Explore the source record for details and available documents.
Biomedical subjects
Publications and source records attributed to A Kucak.
Explore the source record for details and available documents.
The study compares nitric acid and ethylenediaminetetraacetic acid (EDTA) extraction of forest soils for the analysis of trace metals Fe, Mn, Zn, Cu, Pb, and Cd. Fifty forest soil samples from ten different locations were extracted using both methods. The two extraction procedures were compared through regression analysis for each element. All elements were analysed by flame atomic absorption spectrometry method (AAS). The results show that both extracting procedures are only partially effective for most of the measured trace elements in soil. The extraction with diluted HNO3 was incomplete, as large amounts of siliceous material remained undigested. Recoveries obtained by this method for Fe, Mn, Zn, Cu, Pb, and Cd on certified reference material (San Joaquin Soil) were 34, 79, 47, 56, 71, and 102%, respectively. EDTA extraction was even less effective and is considered to reflect the quantity of bioavailable metals. The respective recoveries were 2, 45, 7, 20, 38 and 74%. The regression analyses performed for EDTA-extractable vs. HNO3-extractable metals of forest soils showed high and significant correlation for all examined metals, except Fe.
A microwave digestion method for mushrooms, developed in the study, allows fast preparation of samples and reduces the contamination risk in the process of determining trace metals. Concentrations of six trace elements, Fe, Mn, Cu, Zn, Pb, and Cd were measured in 50 samples of different species of edible mushrooms (fam. Boletaceae) using atomic absorption spectrometry after microwave and dry ashing procedure. The methods were validated through certified Standard Reference Material SRM 1577b (Bovine Liver) which was treated and analysed using the same procedures as for the mushrooms. The samples were either digested with concentrated HNO3 in closed Teflon PFA vessels in a microwave oven, or ashed in quartz crucibles at 450 degrees C. The respective recoveries of Fe, Mn, Zn, Cu, Pb, and Cd obtained by measuring SRM were 112, 107, 104, 115, 111 and 95% after microwave digestion procedure and 86, 101, 109, 111, 98, and 110% after dry ashing procedure. The correlation between concentrations obtained by the two different methods of sample preparation was high for all metals.
The concentration of trace elements (Cd, Cu, Fe, Mn, and Zn) was measured in different species of mushrooms (Boletaceae) and correlated with corresponding elements in soil. Five different species of Boletaceae mushrooms and soil samples were collected from forests of Varazdin county in Croatia. Trace elements were analyzed by atomic absorption spectrometry in mushrooms and in EDTA-extracted soil. The results showed that Cd, Cu, and Zn are concentrated in mushroom tissue from soil with transfer factors (mushroom/soil) of 27.0,10.5, and 12.5, respectively. Cadmium incorporated much less in Leccinum (mean 0.73 mg/kg dry weight) than in Boletus, Xerocomus, or Gyroporus (respective means, 6.8, 8.4, and 12.3 mg/kg). Copper and Zn were accumulated in all collected mushrooms (14.7-35.6 and 109-179 mg/kg, respectively) with no difference among species. There was no accumulation of Fe and Mn in mushrooms, but concentrations differed between species, with lowest values in Leccinum. Iron varied from 31 to 878 mg/kg and Mn from 2.9 to 409 mg/kg. Correlations between elements in mushrooms and soil were significant only for Mn. Because no significant correlations for Cd, Cu, Zn, and Fe between mushrooms and soil were found, more studies are needed with only one species of mushrooms collected at locations with different levels of soil contamination. In spite of higher concentrations of Cd in some Boletaceae species, it is assumed that Cd intake through moderate mushroom consumption remains below suggested Provisional Tolerable Weekly Intake (FAO/WHO).