Selenium can be highly toxic in excess for both animals and humans. However, since its mobile forms can be easily adsorbed with ferric minerals, its mobility in the natural oxic environment is generally not an issue. Still, the removal and immobilization of the long-lived radioactive isotope 79Se from the contaminated anoxic waters is currently a significant concern. 79Se can be accessible in the case of radionuclides' leaching from radioactive waste disposals, where anoxic conditions prevail and where ferrous ions and Fe(II)-bearing minerals predominate after corrosion processes (e.g., magnetite). Therefore, reductive and adsorptive immobilizations by Fe(II)-bearing minerals are the primary mechanisms for removing redox-sensitive selenium. Even though the information on the sorptive interactions of selenium and Fe(II)-bearing minerals seems to be well documented, this review focuses specifically on the state of the available information on the effects of the redox properties of Fe(II)-bearing solid phases (e.g., ferrous oxides, hydroxides, sulfides, and carbonates) on selenium speciation via redox transformation and co-occurring coprecipitation.

• Klíčová slova
• ferrous minerals, nuclear waste, reduction processes, selenium, sorption,
• MeSH
• lidé MeSH
• minerály MeSH
• oxidace-redukce MeSH
• radioaktivní odpad * MeSH
• selen * MeSH
• voda MeSH
• železité sloučeniny MeSH
• železnaté sloučeniny MeSH
• železo MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• minerály MeSH
• radioaktivní odpad * MeSH
• selen * MeSH
• voda MeSH
• železité sloučeniny MeSH
• železnaté sloučeniny MeSH
• železo MeSH

Ferrous slag produced by a historic smelter is washed from a slagheap and transported by a creek through a cave system. Slag filling cave spaces, abrasion of cave walls / calcite speleothems, and contamination of the aquatic environment with heavy metals and other toxic components are concerns. We characterize the slag in its deposition site, map its transport through the cave system, characterize the effect of slag transport, and evaluate the risks to both cave and aqueous environments. The study was based on chemical and phase analysis supported laboratory experiments and geochemical modeling. The slag in the slagheap was dominated by amorphous glass phase (66 to 99 wt%) with mean composition of 49.8 ± 2.8 wt% SiO2, 29.9 ± 1.6 wt% CaO, 13.4 ± 1.2 wt% Al2O3, 2.7 ± 0.3 wt% K2O, and 1.2 ± 0.1 wt% MgO. Minerals such as melilite, plagioclase, anorthite, and wollastonite / pseudowollastonite with lower amounts of quartz, cristobalite, and calcite were detected. Slag enriches the cave environment with Se, As, W, Y, U, Be, Cs, Sc, Cd, Hf, Ba, Th, Cr, Zr, Zn, and V. However, only Zr, V, Co, and As exceed the specified limits for soils (US EPA and EU limits). The dissolution lifetime of a 1 mm3 volume of slag was estimated to be 27,000 years, whereas the mean residence time of the slag in the cave is much shorter, defined by a flood frequency of ca. 47 years. Consequently, the extent of slag weathering and contamination of cave environment by slag weathering products is small under given conditions. However, slag enriched in U and Th can increase radon production as a result of alpha decay. The slag has an abrasive effect on surrounding rocks and disintegrated slag can contaminate calcite speleothems.

• Klíčová slova
• Environmental risk, Experimental abrasion, Ferrous slag, Pollutant release, Rudice Sink – Býčí skála Cave System, Slag transport/weathering,
• MeSH
• kadmium analýza   MeSH
• křemen analýza   MeSH
• minerály analýza   MeSH
• oxid hořečnatý analýza   MeSH
• oxid křemičitý analýza   MeSH
• půda MeSH
• radon * analýza   MeSH
• silikáty MeSH
• sloučeniny vápníku MeSH
• těžké kovy * analýza   MeSH
• uhličitan vápenatý analýza   MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Česká republika MeSH
• Názvy látek
• calcium silicate MeSH Prohlížeč
• kadmium MeSH
• křemen MeSH
• minerály MeSH
• oxid hořečnatý MeSH
• oxid křemičitý MeSH
• půda MeSH
• radon * MeSH
• silikáty MeSH
• sloučeniny vápníku MeSH
• těžké kovy * MeSH
• uhličitan vápenatý MeSH

Electroactive Fe-biochar has attracted significant attention for As(III)/Cr(VI) immobilization through redox reactions, and its performance essentially lies in the regulation of various Fe/C moieties for desired redox performance. Here, a series of Fe-biochar with distinct Fe/C speciation were rationally produced via two-step pyrolysis of iron minerals and biomass waste at 400-850 °C (BCX-Fe-Y, X and Y represented the first- and second-step pyrolysis temperature, respectively). The redox transformation of Cr(VI) and As(III) by Fe-biochar was evaluated in simulated wastewater under oxic or anoxic conditions. Results showed that more effective Cr(VI) reduction could be achieved by BCX-Fe-400, while a higher amount of As (III) was oxidized by BCX-Fe-850 under the anoxic environment. Besides, BCX-Fe-400 could generate more reactive oxygen species (e.g.,•OH) by reducing the O2, which enhanced the redox-related transformation of pollutants under the oxic situation. The evolving redox performance of Fe-biochar was governed by the transition of the redox state from reductive to oxidative related to the Fe/C speciation. The small-sized amorphous/low-crystalline ferrous minerals contributed to a higher electron-donating capacity (0.43-1.28 mmol g-1) of BCX-Fe-400. In contrast, the oxidative surface oxygen-functionalities (i.e., carboxyl and quinoid) on BCX-Fe-850 endowed a stronger electron-accepting capacity (0.71-1.39 mmol g-1). Moreover, the graphitic crystallites with edge-type defects and porous structure facilitated the electron transfer, leading to a higher electron efficiency of BCX-Fe-850. Overall, we unveiled the roles of both Fe and C speciation in maneuvering the redox reactivity of Fe-biochar, which can advance our rational design of electroactive Fe-biochar for redox-related environmental remediation.

• Klíčová slova
• Electron transfer, Engineered biochar, Mineral transformation, Reduction-oxidation, Sustainable waste management,
• MeSH
• arsen * MeSH
• chrom * chemie   MeSH
• dřevěné a živočišné uhlí chemie   MeSH
• minerály MeSH
• oxidace-redukce MeSH
• uhlík MeSH
• železo chemie   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• arsen * MeSH
• biochar MeSH Prohlížeč
• chrom * MeSH
• dřevěné a živočišné uhlí MeSH
• minerály MeSH
• uhlík MeSH
• železo MeSH

The impact of calcium-enriched biochar (BC, containing Ca, Al, Fe and P as dominant elements in the range of 6.9-1.3% with alkaline pH) obtained from sewage sludge (0.1 or 0.5% in the final soil) on cadmium-induced toxicity (final dose of 1.5 mg Cd/kg in control and 4.5 or 16.5 mg Cd/kg soil in low and high Cd treatment) was tested in medicinal plant Matricaria chamomilla. Low Cd dose had typically less negative impact than high Cd dose at the level of minerals and metabolites and the effect of BC doses often differed. Contrary to expectations, 0.5% BC with a high Cd dose increased Cd accumulation in plants about 2-fold. This was reflected in higher signals of reactive oxygen species, but especially the high dose of BC increased the amount of antioxidants (ascorbic acid and non-protein thiols), minerals and amino acids in shoots and/or roots and usually mitigated the negative effect of Cd. Surprisingly, the relationship between BC and soluble phenols was negative at high BC + high Cd dose, whereas the effect of Cd and BC on organic acids (mainly tartaric acid) differed in shoots and roots. Interestingly, BC alone applied to the control soil (1.5 mg total Cd/kg) reduced the amount of Cd in the plants by about 30%. PCA analyses confirmed that metabolic changes clearly distinguished the high Cd + high BC treatment from the corresponding Cd/BC treatments in both shoots and roots. Thus, it is clear that the effect of biochar depends not only on its dose but also on the amount of Cd in the soil, suggesting the use of Ca-rich biochar both for phytoremediation and safer food production.

• Klíčová slova
• Bioremediation, Heavy metals, Krebs acids, Oxidative stress, Phenols,
• MeSH
• aminokyseliny MeSH
• dřevěné a živočišné uhlí MeSH
• fenoly analýza   MeSH
• kadmium * analýza   MeSH
• kyselina askorbová MeSH
• látky znečišťující půdu * analýza   MeSH
• minerály MeSH
• odpadní vody MeSH
• půda chemie   MeSH
• reaktivní formy kyslíku MeSH
• sulfhydrylové sloučeniny MeSH
• vápník analýza   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• aminokyseliny MeSH
• biochar MeSH Prohlížeč
• dřevěné a živočišné uhlí MeSH
• fenoly MeSH
• kadmium * MeSH
• kyselina askorbová MeSH
• látky znečišťující půdu * MeSH
• minerály MeSH
• odpadní vody MeSH
• půda MeSH
• reaktivní formy kyslíku MeSH
• sulfhydrylové sloučeniny MeSH
• vápník MeSH

The dynamics of 38 biochemical parameters of blood, serum and urine was studied in ten heifers during their oestrous cycle in a light house (80-340 lux) and a dark small house (10-40 lux). In the light stable a significant influence (P less than 0.05) was found to be exerted on five parameters and in the dark stable nine parameters, four being influenced in the same way in both houses: haematocrit value and haemoglobin in blood and cholesterol and progesterone in serum; the relationship of progesterone content in serum to the days of oestrous cycle was particularly high in the light house. The comparison of the parameters between the groups demonstrated a significant (P less than 0.05) influence of light regime, exerted on some days of the oestrous cycle upon the levels of inorganic phosphorus, total protein and aspartate aminotransferase activity (AST) in serum and upon haematocrit, haemoglobin and ketone bodies in the blood of heifers. However, the light regime did not influence the levels of progesterone which were somewhat higher in the light house but with no statistically significant difference from the dark house. A significant difference between the groups was obtained in the levels of sodium and phosphorus in urine (P less than 0.05) between the first and tenth days of the oestrous cycle. No differences in the oestrous cycle between the heifers in the light and dark stables were recorded. Neither was the duration of heat influenced significantly; it was only less manifest in the dark stable.

• MeSH
• cholesterol krev   MeSH
• estrus * MeSH
• hematokrit veterinární   MeSH
• hemoglobiny analýza   MeSH
• minerály krev   MeSH
• osvětlení * MeSH
• progesteron krev   MeSH
• skot krev   MeSH
• těhotenství MeSH
• zvířata MeSH
• Check Tag
• skot krev   MeSH
• těhotenství MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• anglický abstrakt MeSH
• časopisecké články MeSH
• Názvy látek
• cholesterol MeSH
• hemoglobiny MeSH
• minerály MeSH
• progesteron MeSH

The quality of potatoes from organic and conventional farming was investigated in this study. Tubers of eight potato varieties, organically and conventionally produced at one or two geographical sites in controlled field trials, were collected in four consecutive harvests from 1996-1999. The parameters analysed included nitrate, trace elements (As, Cd, Co, Cu, Fe, Hg, Mn, Ni, Pb, Se, Zn), vitamin C, potato glycoalkaloids, as well as chlorogenic acid, polyphenol oxidase and rate of tuber enzymic browning. The results indicated lower nitrate content and higher vitamin C and chlorogenic acid content to be the parameters most consistently differentiating organically from conventionally produced potatoes. Elevated concentrations of glycoalkaloids were also observed throughout the experiments in some potato varieties grown in organic farming systems. Principal component analysis (PCA) of the analytical and other data using three PCs confirmed a good separation between the organically and conventionally produced potatoes when studied in single crop years. However, score-plots (objects) and loading-plots (variables) of pooled results from the consecutive harvests showed that between the years' changes and also variety as well as geographical variations are equally or more important factors determining the quality of potatoes than the farming system. Further studies of various marker compounds of potato quality related to the organic or conventional farming systems should be performed before unbiased information can be given to the consumers.

• MeSH
• alkaloidy analýza   MeSH
• analýza hlavních komponent MeSH
• analýza potravin metody   MeSH
• barva MeSH
• biopotraviny analýza   normy   MeSH
• chuť MeSH
• dusičnany analýza   MeSH
• kyselina askorbová analýza   MeSH
• mikroživiny analýza   MeSH
• Solanum tuberosum chemie   enzymologie   normy   MeSH
• stopové prvky analýza   MeSH
• vaření MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• alkaloidy MeSH
• dusičnany MeSH
• kyselina askorbová MeSH
• mikroživiny MeSH
• stopové prvky MeSH

During a rescue excavation in October 2011, archaeologists discovered a mass grave with 10 individuals. The skeletons should belong to victims of the battle of Reichenberg between the Austrian and Prussian armies on April 21, 1757. Several bones of the skeletons were covered with a blue colored encrustation. Initial DNA analysis failed due to strong inhibition. Chemical analysis of the bluish encrustation indicated the presence of the iron phosphate mineral vivianite (Fe3(PO4)2·(H2O)8). This technical note describes a novel procedure for the removal of this inhibitory substance.

• Klíčová slova
• DNA extraction, PCR inhibitors, Vivianite,
• MeSH
• DNA fingerprinting MeSH
• DNA izolace a purifikace   MeSH
• fosfáty škodlivé účinky   MeSH
• lidé MeSH
• odběr biologického vzorku přístrojové vybavení   metody   MeSH
• pohřeb MeSH
• polymerázová řetězová reakce * MeSH
• soudní antropologie přístrojové vybavení   metody   MeSH
• železnaté sloučeniny škodlivé účinky   MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• DNA MeSH
• ferrous phosphate MeSH Prohlížeč
• fosfáty MeSH
• železnaté sloučeniny MeSH

• MeSH
• erytrocyty metabolismus   MeSH
• hemoglobiny analýza   MeSH
• hornictví * MeSH
• lidé MeSH
• methemoglobin analýza   MeSH
• nemoci z povolání chemicky indukované   MeSH
• odběr vzorku krve MeSH
• uran škodlivé účinky   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• hemoglobiny MeSH
• methemoglobin MeSH
• uran MeSH

• MeSH
• časové faktory MeSH
• dospělí MeSH
• erytrocyty účinky záření   MeSH
• hemoglobinometrie MeSH
• hemoglobiny účinky záření   MeSH
• hornictví MeSH
• lidé MeSH
• methemoglobin účinky záření   MeSH
• pracovní lékařství MeSH
• radiační účinky * MeSH
• uran * MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• mužské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• hemoglobiny MeSH
• methemoglobin MeSH
• uran * MeSH

• MeSH
• časové faktory MeSH
• dospělí MeSH
• erytrocyty metabolismus   MeSH
• hemoglobinometrie MeSH
• hemoglobiny biosyntéza   MeSH
• hornictví MeSH
• lidé středního věku MeSH
• lidé MeSH
• methemoglobin metabolismus   MeSH
• oxidace-redukce MeSH
• uran MeSH
• vystavení vlivu životního prostředí MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• hemoglobiny MeSH
• methemoglobin MeSH
• uran MeSH