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101.
Edible mushrooms (Albatrellus ovinus, Boletus edulis, Clitocybe odora, Gomphidius glutinosus, Leccinum scabrum, Leccinum versipelle, Lycoperdon perlatum, Suillus bovinus, Suillus luteus, and Xerocomus subtomentosus) collected from unpolluted areas of the city of Umeå and its outskirts in the northern part of Sweden were examined for contents of toxic metallic elements (Cd, Pb, and Ag) and essential macro- and microelements (K, Na, Ca, Mg, Cu, Fe, Mn, and Zn) using a validated method and a final measurement by flame atomic absorption spectroscopy (F-AAS). The median values of the toxic metallic element concentrations (in mg kg?1 dry biomass, db) ranged from: 0.12–3.9, 0.46–5.1, and 0.91–6.2 for Ag, Cd and Pb, respectively. For the essential metallic elements, the median values of concentrations ranged from: 24000–58000, 15–2000, 59–610, 520–1900, 2.0–97, 16–150, 15–120, and 4.3–26 mg kg?1 db for K, Na, Ca, Mg, Cu, Zn, Fe, and Mn, respectively. The baseline concentrations of the metallic elements determined in mushrooms were mainly affected by the fungal species. The assessed probable maximal dietary intake of Cd (0.002 mg kg?1 body mass) solely from a mushroom meal was only slightly below a revised value of the tolerable weekly intake for this element, while for Pb (0.003 mg kg?1 body mass) it was tenfold below the provisionally tolerable weekly intake.  相似文献   
102.
ABSTRACT

Lead (Pb), cadmium (Cd), and mercury (Hg) contents in ten species of edible mushrooms in Trako??an, Croatia were determined. In addition, the similarity between the studied species was determined by cluster analysis. The caps and stipes of the fruiting bodies were analysed separately. The analyses were carried out by inductively coupled plasma - optical emission spectrometry (ICP-OES). The greatest mean lead concentrations of 1.91 and 1.60 mg kg ?1 were determined in caps and stipes of Macrolepiota procera. The greatest mean concentrations of cadmium (3.23 and 2.24 mg kg?1) were determined in caps and stipes of Agaricus campestris and of mercury (2.56 and 2.35 mg kg?1) in Boletus edulis. In terms of the anatomical parts of the fruiting body (cap-stipe), a considerably greater concentration of the analysed elements was found in the cap for all mushroom species. According to calculated bio-concentration factors, all the examined species were found to be bio-accumulators of Cd and Hg. On the basis of the accumulation of the studied metals, great similarity of mushroom species belonging to the same genus and partial similarity of species of the same ecological affiliation was obtained by cluster analysis.  相似文献   
103.
Pseudomorphs of barite (BaSO4) and Cd-rich ZnS after whewellite (CaC2O4·H2O) occur within remnants of Scots pine bark tissues in the peat layer of a poor fen located near a zinc smelter in south Poland. A two-step formation of the pseudomorphs is postulated based on SEM observations: (1) complete dissolution of whewellite, possibly caused by oxalotrophic bacteria, and (2) subsequent bacterially induced precipitation of barite and spheroidal aggregates of ZnS together with galena (PbS) in voids left by the dissolved whewellite crystals. Local increase in pH due to microbial degradation of whewellite, elevated concentrations of Zn(II) and Ba(II) in pore water due to the decomposition of atmospheric particles of sphalerite and barite in the acidic (pH 3.5–3.8) environment, oxidation of S species during drying and rewetting of the peat layer, and subsequent partial reduction of sulfate anions by sulfur-reducing bacteria were all factors likely involved in the crystallization of ZnS and barite in the microenvironment of the post-whewellite voids.  相似文献   
104.
Fungi can effectively accumulate various metallic elements, metalloids and non-metals in fruiting bodies. This study provides information on the accumulation of Ag, As, Ba, Cd, Co, Cs, Cu, Cr, Li, Mn, Ni, Pb, Rb, Sr, V, Tl, U and Zn in the edible mushroom Sarcodon imbricatus (L.) P. Karst. using the technique of inductively coupled plasma – mass spectrometry with a dynamic reaction cell mode. Mushrooms were foraged from four regions in Poland. Baseline concentrations of minerals, expressed in mg kg?1 dry biomass (db), were in the composite samples of caps in the range: for Ag (0.27–0.29), As (1.0–1.9), Ba (0.31–0.45), Cd (4.5–6.3), Co (0.23–1.9), Cu (28–35), Cr (0.19–0.29), Cs (20–38), Li (0.013–0.020), Mn (5.9–8.8), Ni (0.81–1.4), Pb (0.94–1.6), Rb (490–700), Sr (0.14–0.19), Tl (0.058–0.11), U (0.002–0.002), V (0.044–0.054) and Zn (140–160). Concentration levels of Ag, As, Cd, Cs, Pb and Zn were higher in caps than in stipes of S. imbricatus, whereas for other elements the distribution between caps and stipes was nearly equal or for some differed depending on the location. Certainly, the content of toxic Cd in S. imbricatus was elevated (0.45–0.63 mg kg?1 in fresh caps) and therefore eating this mushroom could increase exposure to Cd. In addition, the content of toxic As in S. imbricatus was elevated.  相似文献   
105.
The aim of the study was to develop a set of curricula for teaching Occupational Safety and Ergonomics at colleges and universities of various types, aimed at equipping students with knowledge and skills and at shaping active attitudes towards the practical application of the acquired knowledge in their future working lives. On the basis of the analysis of the curricula at Polish and foreign colleges and universities, a set (canon) of educational contents constituting a common practice in the academic teaching of Occupational Safety and Ergonomics was established. Then, a convenient for teaching this subject classification of university specialisations in Poland was introduced. This led to identifying and defining a taxonomic unit called here an educational profile. Next, curriculum minima for the developed profiles were defined objectively. To achieve this aim, the set of educational contents was ranked by university teachers and specialists in occupational safety and ergonomics. Each part of the educational contents (subject) was ranked on a 10-point scale in relation to each educational profile. The results of this ranking led to formulating sets of educational contents for each educational profile. On this basis, a repertoire of curricula (6 curricula, in 2 hour-by-hour versions each) was prepared, with methodological guidelines for lecturers. The results of the study were presented in the form of a manual for academic authorities.  相似文献   
106.
Concentrations, composition and interrelationships of selenium and metallic elements (Ag, Ba, Cd, Co, Cr, Cs, Cu, Ga, Mn, Mo, Pb, Rb, Sb, Sr, Tl, V and Zn) have been examined in muscle and organ meats of Red Deer hunted in Poland. The analytical data obtained were also discussed in terms of Se supplementation and deficit to Deer as well as the benefits and risk to humans associated with the essential and toxic metals intake resulting from consumption of Deer meat and products. These elements were determined in 20 adult animals of both sexes that were obtained in the 2000/2001 hunting season from Warmia and Mazury in the north-eastern part of Poland. The whole kidneys contained Ba, Cd, Cr, Ga, Pb, Se, Sr and Tl at statistically greater concentrations than liver or muscle tissue from the same animal. Liver showed statistically greater concentrations of Ag, Co, Cu, Mn and Mo than kidneys or muscle tissue, and muscle tissue was richer in Zn, when compared to the kidneys or liver. Cs and Rb were similarly distributed between all three tissue types, while V was less abundant in liver than kidneys or muscle tissue. There were significant associations between some metallic elements retained in Red Deer demonstrated by Principal Component Analysis (PCA) of the data set. In organ and muscle meats (kidneys, liver and muscle tissue considered together) the first principal component (PC1) was strongly influenced by positively correlated variables describing Se, Ba and Cd and negatively correlated variables describing Ag, Co, Cs, Mn, Pb, Tl and V; PC2, respectively, by Cu, Mn and Mo (+) and Zn (-); PC3 by Ga (+) and PC4 by Sb (+). Selenium occurred in muscle tissue, liver and kidneys at median concentrations of 0.13, 0.19 and 4.0mg/g dry weight, respectively. These values can be defined as marginally deficient (< 0.6mg Se/kg liver dw) or satisfactory (≤ 3.0mg Se/kg kidneys dw) for the amount required to maintain the Deer's body condition and health, depending on the criterion for supplementation used. In terms of human nutritional needs, a relatively high selenium content of kidneys can be beneficial. The muscle meat, liver and kidneys of Red Deer can be considered as a very good source of essential Co, Cr, Cu, Mo, Mn, Se and Zn in the human diet. Lead is generally considered as toxic, and the concentrations found in Red Deer (via the food chain intake) were well below the European Union tolerance limit. Pb from the lead bullets can always create food hygienic problem, if not well recognized during sanitary inspection, and this was noted for one muscle meat sample in this study (5% surveyed). There is no tolerance limit of Cd in game animal meats. The median values of Cd noted in fresh muscle tissue, liver and whole kidneys were 0.07, 0.18, and 3.3mg/kg wet weight, respectively. Cd exists as a chemical element present at trace levels in plants and mushrooms in Deer's food chain in background (uncontaminated) areas. When these are consumed by the Deer, the amount of Cd sequestered with metallothioneins and retained in the organ and muscle meat in this study is low enough to be considered safe for human consumption.  相似文献   
107.
The solubility in pure and saline water at various temperatures was calculated for selected nitro compounds (nitrobenzene, 1,3,5-trinitrobenzene, 2-nitrotoluene, 3-nitrotoluene, 4-nitrotoluene, 2,4-dinitrotoluene, 2,6-dinitrotoluene, 2,3-dinitrotoluene, 3,4-dinitrotoluene, 2,4,6-trinitrotoluene) using the Conductor-like Screening model for Real Solvents (COSMO-RS). The results obtained were compared with experimental values. The COSMO-RS predictions have shown high accuracy in reproducing the trends of aqueous solubilities for both temperature and salinity. The proposed methodology was then applied to predict the aqueous solubilities of 19 nitro compounds in the temperature range of 5-50 °C in saline solutions. The salting-out parameters of the Setschenow equation were also calculated. The predicted salting-out parameters were overestimated when compared to the measured values, but these parameters can still be used for qualitative estimation of the trends.  相似文献   
108.
Larch Bolete (Suillus grevillei) mushrooms collected at spatially distant sites in Poland showed on relative abundance of K, P, Mg, Rb, Al, Ca, Fe (at mg/g dw), Ag, Ba, Cd, Cu, Mn, Na and Zn (at microg/g dw) and less of Co, Cr, Ni, Pb and Sr (<1 microg/g dw). Amongst these elements Rb and K were highly bioconcentrated by Larch Bolete (BCF around 1000 and 300 for the caps), and weaker were Cu, Mg, Na, P and Zn (BCF between 4.1+/-2.5 and 62+/-21). Ag and Cd were bioconcentrated mainly in caps with BCF value of 25+/-16 and 13+/-10. Al, Ba, Ca, Co, Cr, Fe, Mn, Ni, Pb and Sr were excluded (BCF<1) by this species. Intake of meal prepared of 300 g of fresh fruiting bodies of Larch Bolete picked-up at the Western Beskid or Pogórze Wielickie sites in the south of Poland will result in exceeding of oral reference dose set for cadmium. In the case of silver, copper or zinc content a meal of 300 g of fresh or 30 g dried Larch Bolete will not result in exceeding reference doses for these elements. Extent of dose that customer would be exposed after eating of three 300 g fresh the Larch Bolete meals during a week will led to intake of lead and zinc within margin of 0.9-5.1% and 9-16% of PTWI for these elements, respectively. In the case of cadmium and specimens from the Western Beskid or Pogórze Wielickie sites in the south of Poland intake will slightly (around 10%) exceed PTWI value, and for other sites will not exceed (between 2% and 26% of PTWI).  相似文献   
109.
Macro-porosity and leaching of atrazine in tilled and orchard loamy soils   总被引:1,自引:0,他引:1  
Atrazine is the most commonly detected herbicide in the groundwater. Leaching of atrazine largely depends on soil management practices. The aim of this study was to examine leaching of atrazine in tilled and orchard silty loam soils. The experimental objects included: conventionally tilled field (CT) with main tillage operations including pre-plow (10 cm) + harrowing, mouldboard ploughing (20 cm), and a 35 year-old apple orchard (OR) with a permanent sward. To determine leaching of atrazine soil columns of undisturbed structure were taken with steel cylinders of 21.5 cm diameter and 20 cm high from the depth of 0–20 cm. All columns were equilibrated at water content corresponding to field capacity (0.21 kg kg−1). Atrazine suspended in distilled water was dripped uniformly onto the surface of each column. Then water was infiltrated and breakthrough times of leachates were recorded. Atrazine concentration in the leachates was determined by means of HPLC Waters. Macro-porosity and percolation rate were higher in OR than CT soil. Cumulative recovery % of the atrazine applied was 1.267% for OR and approximately one third more from the CT soil but the rate of leaching (per unit of time) was greater from the OR soil. The lower leaching under OR than CT can be due to a greater SOM and the presence of earthworm burrows with organic burrow linings that could adsorb atrazine and contribute to preferential flow allowing solutes to bypass parts whereas the greater rate of leaching due to a greater infiltration rate.The results indicate potential of management practices for minimizing atrazine leaching.  相似文献   
110.
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