We investigated mercury uptake by the polypod fern Dryopteris filix-mas from two mercury emission sites in the Czech Republic along transects of high to low soil Hg concentrations, with the aim to determine whether ferns can accumulate Hg in above-ground biomass where it could disrupt meiotic processes. We focus on Hg because it has been hypothesized to have caused widespread malformation of spores in ferns proliferating in conjunction with one of the Big Five mass extinction events at the end of the Triassic (201.5 Ma). Here, we show that Hg-concentrations in the roots of Dryopteris filix-mas reflect Hg-contamination in the topsoils, while Hg-concentrations in above-ground foliage appears not directly related to topsoil contamination. We employed thermal desorption to determine that fern root systems mainly absorb Hg from soils while above-ground biomass may also have received Hg via gaseous atmospheric uptake. Further detailed Hg-concentration analyses of various fern parts led to the new insight that the highest levels of Hg reside in the spore-producing sori where it could in theory disrupt sporogenesis. To further examine the role of Hg in driving malformations, we isolated Dryopteris spores for microscopic inspection. However, no clear correlation was established between the relative abundance of aberrant spores and Hg-contamination in ferns or soils. Hence, other factors such as temperature, moisture availability, hybridization and other toxic metals likely also influenced fern reproduction. Nevertheless, the high bioaccumulation of Hg in the spore-producing sori should stimulate further research into the binding and influence of Hg by ferns and its role as a driver of plant sterility across mass extinction events.

We describe a continuous section across the Cretaceous-Paleogene boundary (K-Pg boundary) at Uzgrun, Czech Republic (Outer Carpathian Flysch), which comprises distal turbidite facies deposited in a deep marine environment below the carbonate compensation depth (sub-CCD). Biostratigraphic control is based on dinoflagellates, radiolarians, and benthic foraminifera, and calcareous nannofossils and planktonic foraminifers are solely found within the upper Maastrichtian turbidite claystone. The uppermost part of the section, containing the K-Pg boundary, is carbonate-free. The K-Pg boundary is marked by iridium enrichment representing an enhanced extraterrestrial admixture at the base of the turbiditic claystone. Although a boundary clay layer is absent, this layer is likely represented by material reworked and redeposited by turbidity currents. The first occurrence of the dinocyst Senoniasphaera inornata within the C29r magnetochron appears only 8 cm above the iridium anomaly, and the lowest occurrence of the radiolarian Paleocene marker species Amphisphaera aotea is recorded 17 cm above it. Deep-sea agglutinated foraminifera abundance decreases slightly above the K-Pg boundary but also in certain intervals of the uppermost Maastrichtian. No clear mercury enrichment potentially linked to Deccan volcanism was detected. Instead, Hg contents are most likely influenced by post-depositional and redepositional processes, such as the degradation of organic matter (OM). Nevertheless, the occurrence of warm-water taxa, e.g. M. prinsii, in the section might indicate warming associated with greenhouse effect of volcanism. Notwithstanding CCD shallowing, evidenced by disappearance of carbonate in the uppermost Maastrichtian and Paleocene strata, the magnetic signal provides no indication of ocean acidification. From the uppermost Maastrichtian onward, an increase in bottom-water oxygenation is suggested by several proxies, including magnetic hardening, pyrite oxidation, increase in pristane/phytane ratio, and benthic foraminifera assemblages. Enhanced terrigenous OM input during the latest Maastrichtian is evidenced by kerogen composition, C27/C29 sterane ratio, and the terrestrial/aquatic ratio (TAR) index. Overall, the Uzgrun section provides a unique continuous biostratigraphic record of abyssal flysch setting in the Alpine-Carpathian realm, indicating that the K-Pg boundary event exerted only a minor influence on abyssal benthic communities.

Vegetation plays a pivotal role in the global mercury (Hg) cycle through the uptake of atmospheric Hg and its subsequent transfer to soils via litterfall (LF), as well as through Hg deposition on leaf surfaces that is washed off by precipitation and throughfall (TF). Yet, global LF and TF fluxes to soils remain poorly constrained, particularly across biomes and climate regions. Moreover, methylmercury (MeHg), that is the most bioavailable and toxic form of Hg, has long been overlooked in terrestrial Hg budgets despite its non-negligible contribution.This database is the first effort to systematically compile and harmonize all available data on total Hg (THg) and MeHg concentrations and fluxes in LF and TF, ensuring that only datasets with comparable sampling protocols are included. The result is the first global Mercury litter- and throughFall Database (MFallDa, https://doi.org/10.5281/zenodo.21979622, [1]). The dataset includes measurements collected between 1987 and 2024 from 147 sites spanning all major biomes, together with metadata on ecosystem type, sampling protocols, precipitation, wet deposition, and Köppen–Geiger climate classification. MFallDa provides an open-access, standardized resource to improve spatially explicit estimates of vegetation-mediated Hg inputs to soils, and refine inter- and intra-site Hg budgets. To facilitate community data sharing and ensure regular updates, a contribution template is provided and the database is hosted on GitHub enabling collaborative input from the global research community. By collecting and standardizing these critical data, MFallDa addresses a key data gap, thereby supporting more robust assessments of vegetation-mediated Hg budgets.

Mutated pteridophyte spores occur abundantly in conjunction with the end-Triassic mass-extinction (ETME), ~201.6 million years ago, one of the ‘Big Five’ mass-extinction events of the past 500 million years. Based on high concentrations of sedimentary mercury (Hg) in beds that contain abundant mutated fern spore fossils, it has been hypothesized that volcanogenic Hg-emission from large-scale volcanism in the Central Atlantic Magmatic Province exerted stress on standing and pioneering vegetation, causing malfunctions in meiosis and the production of malformed pteridophyte spores. Here, we provide the first clear in vivo evidence for anomalously high Hg among the plants that survived and proliferated through the ETME using synchrotron X-ray fluorescence (XRF). Our analysis reveals highly enriched values of Hg within the fronds of the earliest Jurassic fern Phlebopteris angustiloba from southern Germany. Intriguingly, P. angustiloba, a member of the Matoniaceae, is recognized as the parent plant which produced malformed spores within the Deltoidospora-Concavisporites complex that are common in the same beds that contain the fossil fern leaves. Using XRF and X-ray absorption near edge structure (XANES) analyses, we made comparisons between the fossil fern leaves and those of extant ferns growing in high-mercury environments in Slovenia, Slovakia, and the Czech Republic. These comparisons suggest that ferns can tolerate elevated Hg-levels and bind it in their placentas with sulfurous compounds. Our combined analysis of extant and extinct ferns suggests that these traits may have evolved in response to past environments with high concentrations of toxic metals—like those caused by magmatically-triggered mass extinctions—during which metal-tolerant strategies would have greatly enhanced survivorship.

OBJECTIVES:In Central Europe, mushroom poisoning is a public health problem as the Czech Republic belongs to the countries with the highest proportion of mushroom pickers. The trends in A. phalloides intoxications, their treatment and outcome were investigated in verified cases, as several antidotes are recommended and their effect is still under discussion. METHODS:Mushroom intoxications in 2010-2024 were searched in the database of the Czech Toxicological Information Centre (TIC) and the Institute of Health Information and Statistics. Intoxications with amatoxins in 2019-2024 were analysed. RESULTS:Mushroom-related consultations of TIC reached an average of 490 calls/year (SD = 130), and 190 subjects/year (SD = 36) were hospitalized. A total of 1,248 mycological identifications and laboratory analyses were performed in 2019-2024; in 45 proven intoxications with amatoxins, lethality was 4.4%. The amount of ingested mushrooms (0.3-8 pieces) was negatively correlated (r = -0.358, p = 0.041) with the latency to symptoms (10.4 ± 1.3 hours), and positively with the duration of hospital stay (7.8 ± 2.3 days, r = 0.356, p = 0.042), peak international normalized ratio (r = 0.445, p = 0.010), and use of elimination methods (r = 0.451, p = 0.008). Later admission correlated with alanine aminotransferase activity (r = 0.318, p = 0.033) and creatinine level (r = 0.447, p = 0.002). Patients with simultaneous amatoxin positivity of blood and urine had a longer hospital stay than those with only one positive sample (14.0 ± 6.6 vs. 7.4 ± 2.1 days, p = 0.018). Of 45 patients, 32 patients were treated with 2 or 3 antidotes; two patients died; an additional critical factor for lethal intoxications was preceding liver or psychic disorders. Eight patients received one antidote and recovered; there was no difference between N-acetylcysteine and silibinin (p > 0.05). Five patients with early admission were treated without antidotes and did not develop hepatotoxicity. CONCLUSIONS:Deaths from unintentional poisoning with amatoxins can be averted. Amount of mushrooms ingested, early treatment with N-acetylcysteine or silibinin, and evidence of amatoxins in blood and urine are key factors. Timely mycological consultations and information for safe mushroom collection, including for immigrants, are crucial.

Tree rings have been used to reconstruct historical atmospheric mercury (Hg) pollution, but the suitability of tree species varies. Species considered suitable, such as European larch and spruce spp., are not always available in urban environments. This study investigated tree species commonly found in and around cities in Central Europe-black locust, Norway maple, cherry and Douglas fir. We compared Hg concentrations in the bole wood and foliage of these species with those of European larch. Samples were collected in & Uacute;sti nad Labem, a Czech city with a history of severe Hg pollution. While Hg concentrations in foliage were similar across all species, we observed considerable variation in Hg concentrations in bole wood. On average, the broadleaved species had eight times less Hg in their bole wood than the conifers, likely due to differences in Hg transfer from the foliage. Among the species analysed, Douglas fir showed potential for Hg dendrochemistry, with high tree-ring Hg concentrations, minimal radial translocation and low variability between trees. Mercury concentrations in the tree rings of cherry and Norway maple correlated with atmospheric Hg emissions; however, high inter-tree variability in cherry and low Hg concentrations in maple limited their reliability. Black locust was found unsuitable, as its tree-ring Hg trends were inconsistent with atmospheric Hg emissions. In urban areas where larch or fir trees are unavailable, it may still be preferable to sample these species from nearby locations rather than rely on the broadleaved species closer to the pollution source.

A miniaturized boron-doped diamond electrode (BDDE) screen-printed electrochemical sensor was used for the determination of trazodone (TZ) in drug samples and combined with hollow-fiber liquid-phase microextraction (HF-LPME) for analysis of TZ in human urine. The electrooxidation pathway of TZ at BDDEs was elucidated through HPLC/MS analysis of electrochemically generated products. Supported by density functional theory (DFT) calculations, a multistep oxidation mechanism involving Meisenheimer rearrangement was proposed. Differential-pulse and square-wave voltammetric methods were optimized for direct analysis of TZ from simple matrices with limit of detection (LOD) of 15 nmol L-1. The method was verified on analysis of drug tablet Trittico, and validated by independent HPLC/DAD method. To enable selective voltammetric determination in human urine, HF-LPME was employed as a preconcentration and cleanup step prior to voltammetric detection. Under optimized conditions with isoamyl benzoate as supported liquid membrane, the combined HF-LPME/SWV approach provided a linear response for TZ in the range of 10-1000 nmol L-1 with LOD = 12 nmol L-1. The combined HF-LPME/SWV method was verified using authentic human urine samples in the concentration range of 20-1000 nmol L-1.

Mercury (Hg) is a contaminant of major concern for public and ecosystem health, known for its toxicity and bioaccumulation in the environment. Reconstructing past Hg pollution, as well as monitoring current Hg concentrations, is therefore essential. Tree rings offer a valuable archive for reconstructing historical atmospheric Hg pollution, yet the reliability of dendrochemical Hg reconstructions depends on understanding all factors that influence Hg accumulation in the xylem. This study investigated whether factors beyond atmospheric Hg concentrations, i.e., climatic variables (temperature and precipitation), tree-ring width, and water content, influenced Hg concentrations in the tree rings of European larch and Douglas fir growing near a chlor-alkali plant in the Czech city of & Uacute;sti nad Labem. Both tree species showed similar long-term trends in Hg concentrations, broadly reflecting historical trends in atmospheric Hg pollution. However, short-term (high-frequency) variability in tree-ring Hg concentrations remaining after detrending was associated with other factors. A positive correlation between water content and Hg concentrations suggested that a fraction of the Hg was retained in xylem sap. In European larch heartwood, Hg concentrations correlated positively with tree-ring width, likely due to heartwood formation processes. In Douglas fir, a positive correlation between August-September precipitation and tree-ring Hg suggested that this tree species' isohydric behaviour affected Hg uptake. These findings indicated that while tree-ring Hg concentrations can serve as proxies for historical atmospheric Hg pollution, other factors, such as tree-ring width, water content, and late-summer precipitation, may modulate the signal and should be considered in dendrochemical Hg reconstructions.

Understanding the historical extent of anthropogenic mercury (Hg) emissions is essential due to Hg's persistence and toxicity, yet long-term atmospheric records are scarce. Tree rings offer a valuable high-resolution archive of historical atmospheric Hg. Here, we used Larix decidua tree rings to reconstruct a century of atmospheric Hg pollution in the Rudňany valley, a heavily contaminated mining area of Hg-rich Fe ores in Central Europe with limited historical air Hg measurements. Tree-ring Hg concentrations allowed reconstructing air Hg concentrations, reflecting changes in smelting technologies, locations and total Hg production. Among the five sites studied, the highest Hg concentrations were found at ZAV (valley entrance) and PAT (near a mining waste heap), with a maximum of 3084 μg kg-1 in a single tree-ring segment at PAT for a 1943-1947 segment, among the highest tree-ring Hg concentrations ever reported. Notably, peak Hg emissions occurred prior to 1960, decades before production peaked, reflecting inefficiencies in smelting technologies. A linear model was used to estimate historical air Hg concentrations from tree-ring data, with outputs consistent with the few available historical measurements. However, site-specific variation in the tree-ring Hg to air Hg ratio suggests that environmental and physiological factors influence Hg concentrations. To assess potential confounding effects, we analyzed tree growth and age-related influences on Hg accumulation. Tree age had only a minor impact on Hg trends. Growth suppression was observed at the highly polluted site ZAV, while tree-ring width at the less contaminated JOZ appeared unaffected by pollution. These findings confirm Larix decidua as a robust archive for Hg reconstruction, capable of recording pollution histories even under extreme contamination and across trees of varying ages.

OBJECTIVES:Nanotechnology is a fast-growing field in both science and industry. However, experimental studies brought warning data concerning the negative effect of engineered nanoparticle exposure leading to oxidative stress, inflammation, decreased immune cell viability, and genotoxicity. The consequences of human exposure may appear with decades of latency. Therefore, more data is needed to identify the hazardous effects of nanoparticles. Exposure should be under control and biomarkers of effect are urgently searched. METHODS:Exposures of researchers working with nanocomposites were measured in yearly intervals for 5 years and biomarkers of oxidative stress and/or antioxidant capacity were analysed. Exposure to aerosols with nanoparticles was measured repeatedly using online and offline instruments during both the machining of geopolymer samples with epoxide resin and nanoSiO2 filler and metal surface welding. The levels of biomarkers of oxidation of lipids, nucleic acids and proteins were analysed in exhaled breath condensate (EBC) of researchers and controls in 2016-2018. In 2019 and 2020, glutathione was measured in plasma to assess their antioxidant status. The trends in both exposure and EBC biomarkers' levels were analysed. RESULTS:On average, 21 researchers were examined yearly (aged 40 ± 5 years, exposure 14 ± 3 years). After 5 years, the mean mass concentration dropped from 0.921 to 0.563 mg/m3 and mean total number of particle concentrations from 146,106 to 17,621/cm3. The majority of biomarkers of oxidation of lipids, proteins and nucleic acids decreased (p < 0.05) during repeated measurements from the highest levels being mostly found in 2016. Glutathione in plasma in 2019-2020 was elevated (p < 0.01) as compared to controls. CONCLUSIONS:The adaptation of long-term exposed researchers may give a plausible explanation. However, to our meaning, the precautionary principle and higher attention of the employers to the potential risk of nanoparticles by reducing nanoparticles exposure by almost one order of magnitude played the key role.

OBJECTIVES:To evaluate the effect of short-term inhalational exposure to nanoparticles released during dental composite grinding on oxidative stress and antioxidant capacity markers. MATERIALS AND METHODS:Twenty-four healthy volunteers were examined before and after exposure in dental workshop. They spent 76.8 ± 0.7 min in the testing room during grinding of dental nanocomposites. The individual exposure to aerosol particles in each participant´s breathing zones was monitored using a personal nanoparticle sampler (PENS). Exhaled breath condensate (EBC), blood, and urine samples were collected pre- and post-exposure to measure one oxidative stress marker, i.e., thiobarbituric acid reactive substances (TBARS), and two biomarkers of antioxidant capacity, i.e., ferric-reducing antioxidant power (FRAP) and reduced glutathione (GSH) by spectrophotometry. Spirometry and fractional exhaled nitric oxide (FeNO) were used to evaluate the effect of acute inhalational exposure. RESULTS:Mean mass of dental nanocomposite ground away was 0.88 ± 0.32 g. Average individual doses of respirable particles and nanoparticles measured by PENS were 380 ± 150 and 3.3 ± 1.3 μg, respectively. No significant increase of the post-exposure oxidative stress marker TBARS in EBC and plasma was seen. No decrease in antioxidant capacity biomarkers FRAP and GSH in EBC post-exposure was seen, either. Post-exposure, conjunctival hyperemia was seen in 62.5% volunteers; however, no impairment in spirometry or FeNO results was observed. No correlation of any biomarker measured with individual exposure was found, however, several correlations with interfering factors (age, body mass index, hypertension, dyslipidemia, and environmental pollution parameters) were seen. CONCLUSIONS:This study, using oxidative stress biomarker and antioxidant capacity biomarkers in biological fluids of volunteers during the grinding of dental nanocomposites did not prove a negative effect of this intense short-term exposure. However, further studies are needed to evaluate oxidative stress in long-term exposure of both stomatologists and patients and diverse populations with varying health statuses.

Asbestos is a substance that was previously widely used in construction and insulation materials, but which currently poses a major environmental and health problem. This article aims to provide information about the occurrence of asbestos, the dangers associated with its use, and the applicable legal regulations relating to its handling and disposal.

We used the catchment mass balance approach to investigate mercury (Hg) cycling at the 14 forested GEOMON catchments of the Czech Geological Survey. The temperate forest catchments had variable exposure to historic high sulfur (S) and Hg emissions, and span a range of size and elevation. We monitored monthly Hg inputs (bulk precipitation, throughfall, litterfall) and outputs (stream runoff) during 2020–2022. The catchments spanned a large gradient of historic Hg deposition, but current Hg patterns more closely aligned with catchment factors like local climate, as influenced by elevation, dissolved organic carbon (DOC) concentrations, and geology. The dominant pathway of Hg input was litterfall (averaging 44.5 ± 15.7 µg m−2 yr−1; > 91

This study investigates a synergistic combination of hollow fiber-based liquid phase microextraction (HF-LPME) and voltammetric analysis using screen-printed boron-doped diamond electrodes (SP-BDDE) for the determination of antihypertensive drug lercanidipine (LCN) in urine, blood plasma, and blood serum. Optimum HF-LPME conditions were: dodecane as supported liquid membrane, Britton-Robinson buffer (BRB) pH 7 as donor solution, BRB pH 3 as acceptor solution, and extraction time 30 min. Square-wave voltammetry (SWV) of 10 μL acceptor solution at SP-BDDE was utilized with amplitude 75 mV, frequency 10 Hz, and potential step 4 mV. The calibration dependence of the combined HF-LPME-SWV method was established in the range of 1-1000 nmol L-1, with limits of quantification (LOQ) and detection (LOD) of 3.3 and 1.1 nmol L-1, respectively. The applicability of the developed method was verified by analysis of human urine, blood plasma, and blood serum samples spiked with 20 and 100 nmol L-1 LCN with recoveries ranging from 93.2 to 112.9 % with respective RSDs 1.72-8.5 % (n = 3).

Aim: To find a practical biomonitoring method for researchers exposed to nanoparticles causing oxidative stress. Methods: In a continuation of a study in 2016-2018, biological samples (plasma, urine and exhaled breath condensate [EBC]) were collected in 2019-2020 from 43 researchers (13.8 +/- 3.0 years of exposure) and 45 controls. Antioxidant status was assessed using glutathione (GSH) and ferric-reducing antioxidant power, while oxidative stress was measured as thiobarbituric acid reactive substances, all using spectrophotometric methods. Researchers' personal nanoparticle exposure was monitored. Results: Plasma GSH was elevated in researchers both before and after exposure (p < 0.01); postexposure plasma GSH correlated with nanoparticle exposure, and GSH in EBC increased. Conclusion: The results suggest adaptation to chronic exposure to nanoparticles, as monitored by plasma and EBC GSH.

AbstractThe long-term effects of the Central Atlantic Magmatic Province, a large igneous province connected to the end-Triassic mass-extinction (201.5 Ma), remain largely elusive. Here, we document the persistence of volcanic-induced mercury (Hg) pollution and its effects on the biosphere for ~1.3 million years after the extinction event. In sediments recovered in Germany (Schandelah-1 core), we record not only high abundances of malformed fern spores at the Triassic-Jurassic boundary, but also during the lower Jurassic Hettangian, indicating repeated vegetation disturbance and stress that was eccentricity-forced. Crucially, these abundances correspond to increases in sedimentary Hg-concentrations. Hg-isotope ratios (δ202Hg, Δ199Hg) suggest a volcanic source of Hg-enrichment at the Triassic-Jurassic boundary but a terrestrial source for the early Jurassic peaks. We conclude that volcanically injected Hg across the extinction was repeatedly remobilized from coastal wetlands and hinterland areas during eccentricity-forced phases of severe hydrological upheaval and erosion, focusing Hg-pollution in the Central European Basin.

Electrochemical methods have undergone many important developments initiated by efforts to increase the sensitivity, selectivity, and stability (S&S&S) and to understand the underlying electrode processes. To meet these goals, there are hardware solutions with applications of new technologies and materials, and software solutions utilizing existing instrumentation. The article presents a viable, easy-to-implement software solution to the main shortcomings of linear sweep voltammetry (low sensitivity, high share of the capacitive component of the current, and the problem of overlapping signals) in the form of elimination voltammetry with a linear scan (EVLS). Based on the different dependences of the individual currents that make up the total voltammetric current (diffusion, charging, kinetics, and various irreversible components) on the scan rate, EVLS can eliminate or preserve particular current components. Increased sensitivity and selectivity can be expected especially in the case of a fully adsorbed electroactive particle subjected to an irreversible electrode process when the elimination of kinetic and capacitive current while preserving the diffusion current provides a theoretically confirmed peak-counter peak signal. EVLS is applicable for testing changes in the polarized electrode/electrolyte interface using EVLS functions eliminating the diffusion component of the current and preserving the kinetic and capacitive currents, which should ensure zero current conduction for a purely diffusion-controlled Nernstian-type reversible process. We point out the strengths, opportunities, and weaknesses of EVLS. Nevertheless, EVLS offers a new tool that contributes to a better understanding of electrochemical processes and their mechanisms.

Dimetindene is a sedating antihistamine indicated for the symptomatic treatment of allergic conditions. Dimetindene is marketed among others under the trade name Fenistil (oral solution). Toxicity data are limited, and there is no consensus on the dose at which children require hospitalization. Objective is to determine the potentially toxic dose in children. Data in children with age up to 15 years were obtained from hospital discharge reports. Of 139 paediatric hospital discharge reports, 23 cases (16.5%) were excluded because of uncertain ingestion. In 116 children (46 boys and 70 girls, mean age 2 years and 9 months ± 1 year and 1 month), the majority of children developed no symptoms (87 children, 75%, mean age 3 years±1 year) and the remaining 29 children (25%, mean age 2 years and 11 months ± 1 year and 3 months) developed only mild and spontaneously resolving symptoms of poisoning after a dose of 0.82 ± 0.32 mg/kg b.w. (range 0.26-1.82 mg/kg). In 98% of all cases, hospitalized children were observed for a maximum 24 h, and their condition did not require specific treatment. In conclusion, the prognosis for accidental dimetindene poisoning in children appears to be good and the minimum toxic dose has been determined to be 0.5 mg/kg b.w.