Modelling the Plant Uptake of Metals from Release Rates Obtained by the EUF Method.

In this study, soil dissolution kinetics were evaluated to predict the metal uptake of lettuce plants under varying conditions of fertilisation and metal pollution. Velocities and time dependencies of soil dissolution obtained by electro-ultrafiltration (EUF), which prevents back reaction, were modelled in three ways, obtained from suspensions in 0.002 M DTPA at determined soil pH levels, for cases in which sampling versus time led to decreasing concentrations. The models yielded a maximum achievable concentration, a timespan needed for it to be reached, a slope, and an intercept of the respective fitted curves. Three geogenically metalliferous soil samples and one ambient soil sample, both as originals, fertilised with PK or soaked with a Cd-Ni-Pb solution, were used as solid samples. The resulting kinetic parameters were correlated with the amounts absorbed by lettuce plants grown with these substrates in pot experiments, which yielded fairly good correlations with Zn, but also with Li and Sr, as well as Ni and Pb, mainly because of differences due to the addition of a metallic salt solution. Plant growth was hardly influenced by the additions.

Dietary deoxynivalenol does not affect mineral element accumulation in breast and thigh muscles of broiler chicken.

Deoxynivalenol (DON), a well-known contaminant of feed, can have negative effects on gut permeability and function in poultry, which then could affect major and trace element content of the broilers' breast and thigh muscles, and ultimately reduce meat quality. To study this hypothesis, DON-contaminated diet was fed to broiler chicks. Two groups of birds were housed in metabolic cages with free access to water and feed, with or without DON (10 mg/kg). After 5 weeks, birds were dissected and samples of the breast and thigh muscles, feed and droppings were analysed for five macro (Ca, K, Mg, Na, and P) and ten micro elements (Al, Cr, Cu, Fe, Mn, Li, Mo, Ni, Pb, Rb, and Zn) by inductively coupled plasma optical emission spectrometry (ICP-OES) or inductively coupled plasma mass spectrometer (ICP-MS) methods. In both groups, increased (p < 0.05) concentrations of Ca Na, Fe, Mn, and Zn were found in thigh muscles compared with the breast, whereas the concentrations of Mg, P, and Rb were higher in the breast muscles. DON had no effect on the elemental contents of the broilers' breast and thigh muscles. In conclusion, DON at a level of 10 mg/kg feed to broiler chicken over of 5 weeks did not alter the macro or micro element composition in muscle meat.

Spatial variation of contaminant elements of roadside dust samples from Budapest (Hungary) and Seoul (Republic of Korea), including Pt, Pd and Ir.

Roadside dusts were studied to explain the spatial variation and present levels of contaminant elements including Pt, Pd and Ir in urban environment and around Budapest (Hungary) and Seoul (Republic of Korea). The samples were collected from six sites of high traffic volumes in Seoul metropolitan city and from two control sites within the suburbs of Seoul, for comparison. Similarly, road dust samples were obtained two times from traffic focal points in Budapest, from the large bridges across the River Danube, from Margitsziget (an island in the Danube in the northern part of Budapest, used for recreation) as well as from main roads (no highways) outside Budapest. The samples were analysed for contaminant elements by ICP-AES and for Pt, Pd and Ir by ICP-MS. The highest Pt, Pd and Ir levels in road dusts were found from major roads with high traffic volume, but correlations with other contaminant elements were low, however. This reflects automobile catalytic converter to be an important source. To interpret the obtained multi-element results in short, pollution index, contamination index and geo-accumulation index were calculated. Finally, the obtained data were compared with total concentrations encountered in dust samples from Madrid, Oslo, Tokyo and Muscat (Oman). Dust samples from Seoul reached top level concentrations for Cd-Zn-As-Co-Cr-Cu-Mo-Ni-Sn. Just Pb was rather low because unleaded gasoline was introduced as compulsory in 1993. Concentrations in Budapest dust samples were lower than from Seoul, except for Pb and Mg. Compared with Madrid as another continental site, Budapest was higher in Co-V-Zn. Dust from Oslo, which is not so large, contained more Mn-Na-Sr than dust from other towns, but less other metals.

Patterns of urban mercury contamination detected by bioindication with terrestrial isopods.

Mercury (Hg) is a trace element with high toxicological impact on potential receptors, including human beings. Global Hg emissions are predicted to increase significantly during the next 40 years. After emission, the metal is transported by air currents and precipitations, leading to increasing depositions even in areas far from emission sources. In the terrestrial environment, Hg is subjected to redistribution and transformation into different inorganic and metal-organic species that are taken up by vegetation and soil organisms. In the present study, the woodlouse (Porcellio scaber) was used as a biological indicator of total Hg pollution in the city of Dornbirn (province of Vorarlberg), Austria. Woodlice were collected from 30 sampling points scattered over the city area, 25 of them situated within a rectangular transect crossing the city area from west-northwest to east-southeast, starting near the Rheintal motorway and ending at the slopes of the Bregenzer Wald hills. In addition to woodlice, soil substrate samples were collected at nine of the selected sampling points. Total Hg concentrations were measured in isopod tissues and soil substrate samples by means of an Hg analyzer. Total Hg concentrations in isopod tissues were significantly correlated with Hg soil contents (P < 0.05). Moreover, a gradient of increasing Hg concentrations was observed in isopod samples along the transect across Dornbirn, with the lowest concentrations detected in woodlouse samples near the Rheintal motorway and the highest levels toward the ascending slopes of the Bregenzer Wald hills. This gradient of increasing Hg concentrations across the city matches a concomitant increase in wet precipitations along the same direction, indicating that deposition by wet precipitation may be an important source for Hg contamination in the city of Dornbirn. Overall, the degree of Hg contamination across the study area can be regarded as rather low, i.e., comparable with concentrations observed in other, unpolluted terrestrial habitats. It is concluded that bioindication by total Hg analysis in woodlice can be applied to distinguish between different levels and sources of contamination in urban areas.

Platinum pollution in road dusts, roadside soils, and tree barks in Seoul, Korea.

This study presents the level of platinum in urban environment in and around Seoul, the capital city of Korea. Road dust, roadside soil, and tree bark samples were collected from the sites of various traffic volumes and from control sites in the suburbs. The above samples were analyzed for Pt by ICP-MS and other heavy metals by ICP-OES. Platinum levels in road dusts and roadside soils from Seoul were in the range of 3.8-444 ng/g (av. 115.0 ng/g) and 0.7-221 ng/g (av. 49.7 ng/g), respectively, whereas those in the suburbs were in the range of 2.3-5.2 ng/g (av. 3.9 ng/g) in road dusts and 0.4-5.1 ng/g (av. 2.4 ng/g) in roadside soils. The highest Pt levels in road dusts were found from major roads with high traffic volume. The remarkable difference in average Pt level between heavy traffic roads (av. 132.2 ng/g) and light traffic roads (av. 22.8 ng/g) reflects that an important source of Pt in roadside environment is automobile catalytic converter. High Pt level in road dust was found from the site of erratic stop-start driving condition, for example, 178 ng/g Pt in road dust around a vehicle crossing gate. Platinum level in tree barks ranged from 0.9 to 4.5 ng/g, which indicates the existence of Pt-containing particulate matter in the atmosphere. Road dusts with high Pt level were enriched in traffic-related heavy metals.

Environmental impact of historical harbour city Zadar (Croatia) on the composition of marine sediments and soils.

Sediment samples and soils along the coast line of the Adriatic Sea were sampled along a transect near the coast line at Zadar/Croatia, ranging from north-western suburbs via the historical centre and the industrial area to south-east suburbs. The sediments were dominated by carbonates and clay minerals, and contaminations with Cd-Cu-Pb-Zn-TOC (total organic carbon) at the historical centre and the industrial site were detected, as well as P and Mo input at the mouth of a small creek, probably from agriculture. No trends between the composition of surface and subsurface sea sediments were seen. At the historic harbour site, total element concentrations versus grain size showed a minimum in the fine silt fraction for most of the elements analysed. The soil samples behind the shoreline were not carbonaceous, but dominated by Fe-Al- oxides, some contained high levels of Be-Cd-Cu-Sn-Zn. Surprisingly, high TOC values within the soils might be assigned to human impacts, not to humus. Contrary to data from street dust samples from Seoul city/Korea, which were measured within our laboratory at the same time, Pt-Ir-Au were at ambient levels due to the limited use of catalysts in cars in the Zadar area at the time of sampling.

A simple micro-photometric method for urinary iodine determination.

BACKGROUND: Urinary iodide concentration (UIC) is useful to evaluate nutritional iodine status. In clinical settings UIC helps to exclude blocking of the thyroid gland by excessive endogenous iodine, if diagnostic or therapeutic administration of radio-iodine is indicated. Therefore, this study established a simple test for the measurement of UIC. METHODS: UIC was analyzed in urine samples of 200 patients. Samples were pre-treated at 95°C for 45 min with ammonium persulfate in a thermal cycler, followed by a photometric Sandell-Kolthoff reaction (SK) carried out in microtiter plates. For method comparison, UIC was analyzed in 30 samples by inductivity coupled plasma mass spectro-metry (ICP-MS) as a reference method. RESULTS: Incubation conditions were optimized concerning recovery. The photometric test correlated well to the reference method (SK=0.91*ICP-MS+1, r=0.962) and presented with a functional sensitivity of 20 µg/L. UIC of patient samples ranged from <20 to 750 µg/L (median 110 µg/L); 90% of the urine samples had iodide concentrations below 210 µg/L. CONCLUSION: The modified SK-test takes approximately 90 min for analyses of 20 urine samples compared with 27 h for ICP-MS. The photometric test provides satisfactory results and can be performed with the basic equipment of a clinical laboratory.

Geophagy and potential health implications: geohelminths, microbes and heavy metals.

The practice of geophagy (soil-eating) is widespread among pregnant and breast-feeding women in sub-Saharan Africa. To assess some of the potential risks accompanying the consumption of geophagic material, we analysed contamination with bacteria, fungi, and geohelminths as well as heavy metals (lead, mercury and cadmium) in 88 African geophagic soil samples, which were purchased in Central, West and East Africa, Europe and the United States. Median microbial viable counts of positive samples were 440 cfu/g (maximum 120,000 cfu/g). The median metal concentrations were 40 mg/kg lead (up to 148 mg/kg), 0.05 mg/kg mercury (up to 0.64 mg/kg), and 0.055 mg/kg cadmium (maximum 0.57 mg/kg). No geohelminth eggs were found in these samples. Our results suggest that geophagic soil samples can be highly contaminated with microbes and may contain high levels of lead. Geophagy, however, is not a cause of adult helminth infection. The periodic consumption of geophagic materials at high dosages might be problematic particularly during pregnancy.

Nutritionally relevant elements in staple foods: influence of arable site versus choice of variety.

Eighteen representative sites for the Austrian grain-growing and eight for the potato-growing zones (soils and crops) were investigated. On each site, total element contents (B, Ba, Ca, Cd, Co, Cu, Fe, K, Li, Mg, Mn, Mo, Na, P, Sr and Zn) were determined in 4-12 varieties of winter wheat (n = 136), 6 varieties of spring durum wheat (n = 30), 5 varieties of winter durum wheat (n = 15), 7 varieties of rye (n = 49), 5 varieties of spring barley (n = 30) and 5 varieties of potatoes (n = 40). Element accumulations in grain species and potato tubers varied significantly with site conditions, with the main exceptions for B in potatoes and wheat as well as for Zn, Cu and Co in durum wheat. On average, across all investigated sites, differences in varieties occurred concerning the elements Ca, Cd, Ba, Sr and Zn (except Zn in potatoes and winter durum). A rough estimation revealed that an average Austrian consumer of wheat, rye and potatoes meets more than 50% of the needs of daily element intake for K, P and Mg, between 36 and 72% for Fe, Zn and Cu, and more than 100% for Co, Mo and Mn. In particular, the elements Ca and Na have to be added from other sources.