Geochemical and Pb isotopic evidence for sources and dispersal of metal contamination in stream sediments from the mining and smelting district of Príbram, Czech Republic

Stream sediments from the mining and smelting district of Príbram, Czech Republic, were studied to determine the degree, sources and dispersal of metal contamination using a combination of bulk metal and mineralogical determinations, sequential extractions and Pb isotopic analyses. The highest metal concentrations were found 3-4 km downstream from the main polymetallic mining site (9800 mg Pb kg(-1), 26 039 mg Zn kg(-1), 316.4 mg Cd kg(-1), 256.9 mg Cu kg(-1)). The calculated enrichment factors (EFs) confirmed the extreme degree of contamination by Pb, Zn and Cd (EF>40). Lead, Zn and Cd are bound mainly to Fe oxides and hydroxides. In the most contaminated samples Pb is also present as Pb carbonates and litharge (PbO). Lead isotopic analysis indicates that the predominant source of stream sediment contamination is historic Pb-Ag mining and primary Pb smelting (206Pb/207Pb=1.16), while the role of secondary smelting (car battery processing) is negligible.     

Socio-demographic determinants of municipal waste generation: case study of the Czech Republic

Journal of Material Cycles and Waste Management - Increasing pressure of the European Union on diverting municipal waste from landfills requires an active role of households and commands a radical...     

Heterogeneous response of central European streams to decreased acidic atmospheric deposition

We investigated the relations between mountain streamwater chemistry and atmospheric pollution in an arca of 1611 km2 of the Czech Republic by comparing concentrations of SO4. NO3, Cl, Ca and the pH at 432 localities at the time of high (1984-1986) and relatively low (1996-2000) acidic atmospheric deposition. Medians of Cl. SO4, and NO3 decreased by 17, 96 and 60 microeq l(-1), or by 23, 17 and 49%, respectively, during 12 +/- 2 years. The decreased Cl corresponds to decreased emission of industrial Cl (as HCl). The decreased stream SO4 was proportionally lower than the 71% decrease in S-emissions due to leaching of previously accumulated SO4 from soils and non-zero background concentrations. Decreases of NO3 up to 60% in streamwaters with pH < or = 6 was greater than the decrease of N emission in central Europe, about 35%. Extensive regional decrease of NO3 is surprising and is probably described for the first time. The difference in NO3 concentrations between the two periods was probably enhanced by (a) an increase of mineralisation of forest floor in the mid-1980s and (b) by higher uptake of N in the late-1990s. The median pH of the 432 streams did not change but the pH of the sub-population with pH < 6 in the mid-1980s recovered substantially. The pH of circum-neutral streams (pH > 6.5) decreased even as acidic atmospheric deposition decreased.     

The use of mosses and pine needles to detect persistent organic pollutants at local and regional scales

Polycyclic aromatic hydrocarbons (PAHs) were analysed in mosses (Hypnum cupressiforme) and pine needles (Pinus sylvestris) collected in the Czech Republic between 1988-94 at a regional background site in Kosetice, south Bohemia (1988-94) and two industrial sources. One industrial site (sampled 1989-91) in middle Moravia, was near a factory producing PAHs, carbon black and phthalates, the other (sampled 1991-93) near a coal and gas fuel production plant in western Bohemia. Selected chlorinated pesticides and polychlorinated biphenyl congeners were also analysed in samples at the regional background site. This study clearly shows that vegetation sampling can be used to show spatial differences in the atmospheric burden of a range of persistent organic pollutants with differences in the mixtures of compounds reflecting differences in their regional or local use/atmospheric emission.     

Mercury in fish tissues in the area of Malachov Hg-ore deposit (Slovakia)

Environmental Geochemistry and Health - The abandoned Malachov deposit belongs among the most important historic Hg deposits in the world. The soil, groundwater, surface water, plants, and animals...     

The role of sulphur in cadmium(II) ions detoxification demonstrated in in vitro model: Dionaea muscipula Ell.

Fertilization by phosphorus and also nitrogen fertilizers are the main source of cadmium soil contamination. Cadmium is relatively easily taken up by plants and then consequently enters their food chain. We investigated whether the cultivation medium with or without sulphates supplement affects the synthesis of protective low molecular mass thiols such as cysteine, reduced glutathione, oxidized glutathione and phytochelatins (PC2) in Dionaea muscipula treated with cadmium(II) ions at 0, 1, 5, 10, 25, 50, 100, 250, 500 and 1,000 μM for 6 weeks. The plants cultivated in the presence of sulphates showed higher cadmium tolerance due to faster growth and lesser number of necrosis hallmarks. Further, we utilized liquid chromatography with electrochemical detection for determination of the thiols in plant tissues. In the case of the plants cultivated on media supplemented with sulphates for 6 weeks the average PC2 level was 2,830 ng/g of fresh weight (FW). However, the plants cultivated on media without the presence of sulphates on average contained 1,160 ng PC2/g FW. Results obtained showed the positive effect of sulphur supplementation in cadmium detoxification processes in plants. In addition to thiol content, we also determined level of majority secondary metabolite of Venus flytrap, naphthoquinone plumbagin. Generally, the presence of sulphates in the media enhanced the protective mechanism and did not affect directly the synthesis of secondary metabolite plumbagin.     

Chlorpyrifos degradation in Turkish soil

Degradation of chlorpyrifos was evaluated in laboratory studies. Surface (0-15 cm) and subsurface (40-60 cm) clay loam soils from a pesticide-untreated field were incubated in biometer flasks for 97 days at 25 degrees C. The treatment was 2 micrograms g-1 [2,6-pyridinyl-14C] chlorpyrifos, with 74 kBq radioactivity per 100 g soil flask. Evolved 14CO2 was monitored in KOH traps throughout the experiment. Periodically, soil subsamples were also methanol-extracted [ambient shaking, then supercritical fluid extraction (SFE)], then analyzed by thin-layer chromatography. Total 14C and unextractable soil-bound 14C residues were determined by combustion. From the surface and subsurface soils, 41 and 43% of the applied radiocarbon was evolved as 14CO2 during 3 months incubation. The time required for 50% loss of the parent insecticide in surface and subsurface soils was about 10 days. By 97 days, chlorpyrifos residues and their relative concentration (in surface/subsurface) as % of applied 14C were: 14CO2 (40.6/42.6), chlorpyrifos (13.1/12.4), soil-bound residues (11.7/11.4), and 3,5,6-trichloropyridinol (TCP) (3.8/4.8). Chlorpyrifos was largely extracted by simple shaking with methanol, whereas TCP was mainly removed only by SFE. The short persistence of chlorpyrifos probably relates to the high soil pH (7.9-8.1).