We conducted a pot experiment with biochar (BC), wood ash (WA), and humic substances (HS) to investigate their effect on As, Zn, Cu, Cd and Pb mobility in soil, as well as enzyme activities involved in C-, N-, and P-cycles, and Eisenia foetida toxicity in multi-contaminated soils. Amendments were dosed to increase еру soil pH from initial 6.0 to ∼6.5 and ∼7.0. Applying amendments has revealed, that WA significantly immobilized Cu, Zn and Pb, BC - Cu and Zn, and HS decreased solely Cu mobility in soil. The partition indices of Zn, Cu, and Pb, quantitatively describing the bioavailable species of elements in soil, were the lowest for WA. Changes in the water-soluble species of metals were more pronounced than in the exchangeable ones for all amendments. An opposite effect was observed on enzyme activity and earthworm toxicity for the WA and carbonaceous amendments. The BC and HS provided favourable soil conditions to dehydrogenase, β-glucosidase, urease activity and fluorescein diacetate hydrolysis, while WA significantly decreased the activity of all the mentioned enzymes in soil. The results are supported by an enzymes-based weighted mean index, being the highest for BC and HS and the lowest for WA (lower than in the control sample). At the same time, WA was suitable to eliminate the trace elements' stress to earthworms (biomass endpoints and cocoons production). Our data revealed that each amendment has its own advantages and disadvantages. The choice of the most suitable amendment therefore should always be made within an integral approach and based on the purpose of remediation.

• MeSH
• Charcoal chemistry   MeSH
• Humic Substances * MeSH
• Soil Pollutants analysis   MeSH
• Oligochaeta metabolism   MeSH
• Soil chemistry   MeSH
• Environmental Restoration and Remediation MeSH
• Trace Elements analysis   MeSH
• Metals, Heavy analysis   MeSH
• Environmental Pollution analysis   MeSH
• Animals MeSH
• Check Tag
• Animals MeSH
• Publication type
• Journal Article MeSH

Nowadays trace metal contamination of soils represents an important environmental hazard. Nevertheless, the use of some secondary waste products as amendments may restore the common soil functions. This paper focuses on the chemical and biological influence of wood biochar (BC), wood ash (WA) and humic substances (HS), alone and in the mixtures, on a heavily multi-contaminated sandy loam soil. The soil was amended by above-mentioned materials to follow a pH-increasing design (pHCa from 6.0 to 6.5, 7.0 and 7.5); soil samples were analyzed after 3, 30, and 60 days using a set of variables, namely the plant-available trace element concentrations (Cu, Cd, and Zn), microbial biomass carbon (Cmic), and microbial quotient (qCO2), as well as toxicity to Sinapis alba and Daphnia magna. Wood ash and WA + HS were the most efficient treatments to decrease mobile Cd and Zn concentrations in the soil, while HS, BC, and BC + HS combinations were the most effective in reducing the Cu mobility. The effect of BC and WA on the Cmic and qCO2 was mostly negative, whereas adding HS markedly increased Cmic and reduced qCO2 in soil. After amendment applications, the root elongation of mustard was significantly increased in HS and combined treatments (BC + HS, WA + HS). Additionally, BC + HS, WA + HS and WA 8.4% significantly decreased the toxicity of leachates to D. magna to the low-, or non-toxic levels. Our results suggest that the combination of amendments with HS can be a suitable remediation strategy for heavily contaminated soils.

• MeSH
• Biomass MeSH
• Charcoal chemistry   MeSH
• Wood chemistry   MeSH
• Humic Substances analysis   MeSH
• Soil Pollutants analysis   MeSH
• Soil chemistry   MeSH
• Environmental Restoration and Remediation methods   MeSH
• Trace Elements analysis   MeSH
• Carbon analysis   MeSH
• Environmental Pollution MeSH
• Publication type
• Journal Article MeSH

Willows (Salix spp.) are considered to be effective for the phytoremediation of trace elements from contaminated soils, but their efficiency is limited in heavily polluted soils because of poor growth. Liming can be a desirable measure to decrease the plant availability of elements, resulting in improved plant development. Notably, large root area and maximum soil penetration are basic parameters that improve the efficiency of phytoremediation. The impact of soil chemical properties on willow root anatomy and the distribution of trace elements below-ground have rarely been studied. The effect of liming on root parameters, biomass allocation and trace element distribution in non-harvestable (coarse roots, fine roots, stumps) and harvestable plant parts (twigs and leaves) of Salix × smithiana was assessed at the end of a 4-year pot experiment with two trace element-polluted soils that differed in terms of soil pH. Stump biomass predominated in weakly acidic soil. In neutral soil, the majority of biomass was located in fine roots and stumps; the difference from other plant parts was minor. Trace elements were the most concentrated in fine roots. Translocation to above-ground biomass increased as follows: Pb < As < Zn~Cd. In contrast to Cd and Zn, great differences in As and Pb mobility in plants were recorded after measurements of individual below-ground biomass (stumps < coarse roots < fine roots). Lime application decreased the concentrations of mobile Cd and Zn and related levels in plants, improved biomass production and root parameters and increased the removal of all trace elements in weakly acidic soil. None or minimum differences in the monitored parameters were recorded for dolomite treatments in both soils. The dose and source of liming had crucial effects on root anatomy. Growing willows in limed trace element-polluted soils is a suitable measure for combination of two remediation strategies, i.e. phytoextraction of Cd and Zn and assisted phytostabilization of As and Pb.

• MeSH
• Biodegradation, Environmental MeSH
• Biomass MeSH
• Plant Roots anatomy & histology   drug effects   MeSH
• Soil Pollutants analysis   metabolism   MeSH
• Oxides chemistry   MeSH
• Soil chemistry   MeSH
• Salix drug effects   growth & development   metabolism   MeSH
• Calcium Compounds chemistry   MeSH
• Trace Elements analysis   metabolism   MeSH
• Metals, Heavy analysis   metabolism   MeSH
• Publication type
• Journal Article MeSH

• MeSH
• Cells * MeSH
• Molecular Biology MeSH

• Conspectus
• Biochemie. Molekulární biologie. Biofyzika
• NML Fields
• molekulární biologie, molekulární medicína
• NML Publication type
• učebnice vysokých škol

The environmental stability of Tl-rich sphalerite in two contrasting soils was studied. Rhizospheric conditions were simulated to assess the risk associated with sulfide microparticles entering agricultural (top)soils. The data presented here clearly demonstrate a significant effect of 500 μM citric acid, a model rhizospheric solution, on ZnS alteration followed by enhanced Tl and Zn release. The relative ZnS mass loss after 28 days of citrate incubation reached 0.05 and 0.03 wt.% in Cambisol and Leptosol samples respectively, and was up to 4 times higher, compared to H2O treatments. Incongruent (i.e., substantially increased) mobilization of Tl from ZnS was observed during the incubation time. Generally higher (long-term) stability of ZnS with lower Tl release is predicted for soils enriched in carbonates. Furthermore, the important role of silicates (mainly illite) in the stabilization of mobilized Tl, linked with structural (inter)layer Tl-K exchange, is suggested. Thallium was highly bioavailable, as indicated by its uptake by white mustard; maximum Tl amounts were detected in biomass grown on the acidic Cambisol. Despite the fact that sulfides are thought as relatively stable phases in soil environments, enhanced sulfide dissolution and Tl/trace element release (and bioaccumulation) can be assumed in rhizosphere systems.

• MeSH
• Models, Chemical * MeSH
• Soil Pollutants analysis   chemistry   MeSH
• Minerals chemistry   MeSH
• Environmental Monitoring MeSH
• Soil chemistry   MeSH
• Rhizosphere MeSH
• Thallium analysis   chemistry   MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH

In vitro tests simulating the elements release from inhaled urban particulate matter (PM) with artificial lung fluids (Gamble's and Hatch's solutions) and simulated gastric and pancreatic solutions were applied for an estimation of hazardous element (As, Cd, Cr, Hg, Mn, Ni, Pb and Zn) bio-accessibility in this material. An inductively coupled plasma optical emission spectrometry (ICP-OES) and an inductively coupled plasma mass spectrometry (ICP-MS) were employed for the element determination in extracted solutions. The effect of the extraction agent used, extraction time, sample-to-extractant ratio, sample particle size and/or individual element properties was evaluated. Different patterns of individual elements were observed, comparing Hatch's solution vs. simulated gastric and pancreatic solutions. For Hatch's solution, a decreasing sample-to-extractant ratio in a PM size fraction of <0.063 mm resulted in increasing leached contents of all investigated elements. As already proved for other operationally defined extraction procedures, the extractable element portions are affected not only by their mobility in the particulate matter itself but also by the sample preparation procedure. Results of simulated in vitro tests can be applied for the reasonable estimation of bio-accessible element portions in the particulate matter as an alternative method, which, consequently, initiates further examinations including potential in vivo assessments.

• MeSH
• Biological Assay methods   MeSH
• Mass Spectrometry MeSH
• Humans MeSH
• Urban Renewal * MeSH
• Particulate Matter analysis   MeSH
• Metals, Heavy analysis   MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH

The biogeochemical cycles of most toxic metals have been significantly altered by anthropogenic activities. Anaerobic, rain-fed organic soils are believed to record historical changes in atmospheric pollution. Suspected postdepositional mobility of trace elements, however, hinders the usefulness of peat bogs as pollution archives. To lower this uncertainty, we quantified the mobility of six trace metals in peat during an 18-month field manipulation. A replicated, reciprocal peat transplant experiment was conducted between a heavily polluted and a relatively unpolluted peatland, located 200 km apart in the Czech Republic (Central Europe). Both peatlands were Sphagnum-derived, lawn-dominated, and had water table close to the surface. A strikingly different behavior was observed for two groups of elements. Elements of group I, Fe and Mn, adjusted their abundances and vertical patterns to the host site, showing an extremely high degree of mobility. In contrast, elements of group II, Pb, Cu, Zn, and Ti, preserved their original vertical patterns at the host site, showing a high degree of immobility. Our experimental results suggest that not just lead, but also copper and zinc concentration profiles in peat are a reliable archive of temporal pollution changes within a wide pH range (2.5-5.8).

• MeSH
• Time Factors MeSH
• Hydrogen-Ion Concentration MeSH
• Metals analysis   MeSH
• Soil Pollutants analysis   MeSH
• Humans MeSH
• Wetlands MeSH
• Environmental Monitoring methods   MeSH
• Groundwater analysis   MeSH
• Soil chemistry   MeSH
• Sphagnopsida chemistry   MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Geographicals
• Czech Republic MeSH

Burkholderia cepacia complex (Bcc) bacteria have gained notoriety as pathogens in cystic fibrosis (CF) because they are difficult to identify and treat, and also have the ability to spread between CF individuals. Of the 17 formally named species within the complex, Burkholderia multivorans and Burkholderia cenocepacia dominate in CF. Multilocus sequence typing has proven to be a very useful tool for tracing the global epidemiology of Bcc bacteria and has shown that B. cenocepacia strains with high transmissibility, such as the ET-12 strain (ST-28) and the Czech strain (ST-32), have spread epidemically within CF populations in Canada and Europe. The majority of research on the molecular pathogenesis of Bcc bacteria has focused on the B. cenocepacia ET-12 epidemic lineage, with gene mutation, genome sequence analysis and, most recently, global gene expression studies shedding considerable light on the virulence and antimicrobial resistance of this pathogen. These studies demonstrate that the ability of B. cenocepacia to acquire foreign DNA (genomic islands, insertion sequences and other mobile elements), regulate gene expression via quorum sensing, compete for iron during infection, and mediate antimicrobial resistance and inflammation via its membrane and surface polysaccharides are key features that underpin the virulence of different strains. With the wealth of molecular knowledge acquired in the last decade on B. cenocepacia strains, we are now in a much better position to develop strategies for the treatment of pathogenic colonization with Bcc and to answer key questions on pathogenesis concerning, for example, the factors that trigger the rapid clinical decline in CF patients.

• MeSH
• Drug Resistance, Bacterial MeSH
• Polysaccharides, Bacterial physiology   MeSH
• Burkholderia cenocepacia classification   genetics   isolation & purification   pathogenicity   MeSH
• Burkholderia cepacia complex classification   genetics   isolation & purification   pathogenicity   MeSH
• Cystic Fibrosis genetics   microbiology   MeSH
• Gene Expression MeSH
• Burkholderia Infections complications   epidemiology   microbiology   MeSH
• Respiratory Tract Infections complications   epidemiology   microbiology   MeSH
• Humans MeSH
• Molecular Epidemiology MeSH
• Multilocus Sequence Typing methods   MeSH
• Mutation MeSH
• Quorum Sensing MeSH
• Interspersed Repetitive Sequences MeSH
• Virulence genetics   MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Review MeSH
• Geographicals
• Europe MeSH
• Canada MeSH

Although the metabolic and toxicological interactions between essential element selenium (Se) and toxic element cadmium (Cd) have been reported for a long time, the experimental studies explored mostly acute, high-dose interactions. Limited data are available regarding the effects of Se-deficiency on toxicokinetics of cadmium, as well as on the levels of key trace elements--copper, zinc, and iron. In the present study, male and female Wistar weanling rats (n = 40/41) were fed either Se-deficient or Se-adequate diet (<0.06 or 0.14 mg Se per kilogram diet, respectively) for 12 weeks, and from week 9 were drinking water containing 0 or 50 mg Cd/l as cadmium chloride. At the end of the 12-week period, trace element concentrations were estimated by AAS. Selenium-deficient rats of both genders showed significantly lower accumulation of cadmium in the liver, compared to Se-adequate rats. Zinc and iron hepatic levels were not affected by Se-deficiency. However, a significant elevation of copper was found in the liver of Se-deficient rats of both genders. Cadmium supplementation increased zinc and decreased iron hepatic level, regardless of Se status and decreased copper concentration in Se-adequate rats. Se-deficiency was also found to influence the effectiveness of cadmium mobilization in male rats.

• MeSH
• Time Factors MeSH
• Cadmium Chloride metabolism   pharmacokinetics   MeSH
• Diet MeSH
• Cadmium administration & dosage   metabolism   pharmacokinetics   MeSH
• Rats MeSH
• Weaning MeSH
• Rats, Wistar MeSH
• Selenium administration & dosage   deficiency   metabolism   MeSH
• Spectrophotometry, Atomic MeSH
• Trace Elements metabolism   pharmacokinetics   MeSH
• Animals MeSH
• Check Tag
• Rats MeSH
• Male MeSH
• Female MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH