Data from 32 long-term (1994–2012) monitoring sites were used to assess temporal development and spatial variability of sulphur (S) and inorganic nitrogen (N) concentrations in bulk precipitation, ...and S in throughfall, for the Czech Republic. Despite large variance in absolute S and N concentration/deposition among sites, temporal coherence using standardised data (Z score) was demonstrated. Overall significant declines of SO4 concentration in bulk and throughfall precipitation, as well as NO3 and NH4 concentration in bulk precipitation, were observed. Median Z score values of bulk SO4, NO3 and NH4 and throughfall SO4 derived from observations and the respective emission rates of SO2, NOx and NH3 in the Czech Republic and Slovakia showed highly significant (p < 0.001) relationships. Using linear regression models, Z score values were calculated for the whole period 1900–2012 and then back-transformed to give estimates of concentration for the individual sites. Uncertainty associated with the concentration calculations was estimated as 20% for SO4 bulk precipitation, 22% for throughfall SO4, 18% for bulk NO3 and 28% for bulk NH4. The application of the method suggested that it is effective in the long-term reconstruction and prediction of S and N deposition at a variety of sites. Multiple regression modelling was used to extrapolate site characteristics (mean precipitation chemistry and its standard deviation) from monitored to unmonitored sites. Spatially distributed temporal development of S and N depositions were calculated since 1900. The method allows spatio-temporal estimation of the acid deposition in regions with extensive monitoring of precipitation chemistry.
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•Temporal coherence of precipitation SO4, NO3 and NH4 was demonstrated.•Regional S and N emissions enabled to reconstruct long-term changes in deposition.•Empirically-based interpolation allowed spatial deposition variations to be mapped.
Abstract
Global chronic nitrogen (N) deposition to forests can alleviate ecosystem N limitation, with potentially wide ranging consequences for biodiversity, carbon sequestration, soil and surface ...water quality, and greenhouse gas emissions. However, the ability to predict these consequences requires improved quantification of hard-to-measure N fluxes, particularly N gas loss and soil N retention. Here we combine a unique set of long-term catchment N budgets in the central Europe with ecosystem
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N data to reveal fundamental controls over dissolved and gaseous N fluxes in temperate forests. Stream leaching losses of dissolved N corresponded with nutrient stoichiometry of the forest floor, with stream N losses increasing as ecosystems progress towards phosphorus limitation, while soil N storage increased with oxalate extractable iron and aluminium content. Our estimates of soil gaseous losses based on
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N stocks averaged 2.5 ± 2.2 kg N ha
−1
yr
−1
and comprised 20% ± 14% of total N deposition. Gaseous N losses increased with forest floor N:P ratio and with dissolved N losses. Our relationship between gaseous and dissolved N losses was also able to explain previous
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N-based N loss rates measured in tropical and subtropical catchments, suggesting a generalisable response driven by nitrate (NO
3
−
) abundance and in which the relative importance of dissolved N over gaseous N losses tended to increase with increasing NO
3
−
export. Applying this relationship globally, we extrapolated current gaseous N loss flux from forests to be 8.9 Tg N yr
−1
, which represent 39% of current N deposition to forests worldwide.
The 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 (δ
Hg, Δ
Hg) 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.
Trees predominantly take up mercury (Hg) from the
atmosphere via stomatal assimilation of gaseous elemental Hg (GEM). Hg is
oxidised in leaves/needles and transported to other tree anatomy including
...bole wood, where it can be stored long-term. Using Hg associated with growth
rings facilitates archiving of historical GEM concentrations. Nonetheless,
there are significant knowledge gaps on the cycling of Hg within trees. We
investigate Hg archived in tree rings, internal tree Hg cycling, and
differences in Hg uptake mechanisms in Norway spruce and European larch
sampled within 1 km of a HgCl2-contaminated site using total Hg (THg)
and Hg stable isotope analyses. Tree ring samples are indicative of
significant increases in THg concentrations (up to 521 µg kg−1) from the background period (BGP; facility closed; 1992–present) to secondary industrial period (2ndIP; no HgCl2 wood treatment; 1962–1992) to primary industrial period (1stIP; active HgCl2 wood
treatment; ≈ 1900–1962). Mass-dependent fractionation (MDF) Hg
stable isotope data are shifted negative during industrial periods (δ202Hg of 1stIP: −4.32 ± 0.15 ‰,
2ndIP: −4.04 ± 0.32 ‰, BGP: −2.83 ± 0.74 ‰; 1 SD). Even accounting for a ≈ −2.6 ‰ MDF shift associated with stomatal uptake,
these data are indicative of emissions derived from industrial activity
being enriched in lighter isotopes associated with HgCl2 reduction and
Hg0 volatilisation. Similar MDF (δ202Hg: −3.90 ± 0.30 ‰; 1 SD) in bark Hg (137 ± 105 µg kg−1) suggests that stomatal assimilation and downward
transport is also the dominant uptake mechanism for bark Hg (reflective of
negative stomatal-uptake MDF shift) rather than deposition to bark. THg was
enriched in sapwood of all sampled trees across both tree species. This may
indicate long-term storage of a fraction of Hg in sapwood or xylem solution. We also observed a small range of odd-isotope mass-independent fractionation (MIF). Differences in Δ199Hg between periods of different industrial activities were
significant (Δ199Hg of 1stIP: 0.00 ± 0.03 ‰, 2ndIP: −0.06 ± 0.04 ‰, BGP: −0.13 ± 0.03 ‰; 1 SD), and we suggest MIF
signatures are conserved during stomatal assimilation (reflect source MIF
signatures). These data advance our understanding of the physiological
processing of Hg within trees and provide critical direction to future
research into the use of trees as archives for historical atmospheric Hg.
The purpose was to study the prevalence and predisposing factors of brain lesions in survivors of acute methanol poisoning. Clinical data on 106 patients with methanol poisoning were collected during ...the Czech mass poisoning outbreak. Of 83 survivors, in 46 (55%) patients, follow‐up examinations including magnetic resonance imaging of brain (MR) were performed 3–8 and 24–28 months after discharge from the hospital. Of 46 patients with a median age of 49 (interquartile range, 35–57) years, 24 (52%) patients had a total of 40 abnormal brain findings with haemorrhagic lesions detected in 15 (33%) and non‐haemorrhagic lesions found in 9 (19%) patients. The patients with haemorrhagic brain lesions were more acidemic (lower arterial blood pH, higher base deficit) and had higher glycaemia and lactacidaemia on admission than those without haemorrhages (all p < 0.05). Thirteen of 32 (41%) of patients with systemic anticoagulation and 2 of 14 (14%) of patients without it had haemorrhagic lesions (p = 0.080). Bleeding complications during the treatment occurred in 4 of 15 (27%) patients, and 5 of 15 (33%) patients had conditions predisposing to haemorrhage in the group with haemorrhagic lesions. In three cases with a series of computer tomography (CT)/MR performed during hospitalization, the necrotic lesions in the brain remained non‐haemorrhagic during hospitalization and haemorrhagic lesions were detected on the follow‐up MR examinations only. No association between brain haemorrhages and systemic anticoagulation during dialysis was found: brain haemorrhages might occur in severely poisoned patients treated without systemic anticoagulation, whereas treatment with high doses of heparin might not lead to brain haemorrhages.
Nanoscale titanium dioxide (nanoTiO
2
) is a commercially important nanomaterial. Animal studies have documented lung injury and inflammation, oxidative stress, cytotoxicity and genotoxicity. Yet, ...human health data are scarce and quantitative risk assessments and biomonitoring of exposure are lacking. NanoTiO
2
is classified by IARC as a group 2B, possible human carcinogen. In our earlier studies we documented an increase in markers of inflammation, as well as DNA and protein oxidative damage, in exhaled breath condensate (EBC) of workers exposed nanoTiO
2
. This study focuses on biomarkers of lipid oxidation. Several established lipid oxidative markers (malondialdehyde, 4-hydroxy-trans-hexenal, 4-hydroxy-trans-nonenal, 8-isoProstaglandin F2α and aldehydes C
6
-C
12
) were studied in EBC and urine of 34 workers and 45 comparable controls. The median particle number concentration in the production line ranged from 1.98 × 10
4
to 2.32 × 10
4
particles/cm
3
with ∼80% of the particles <100 nm in diameter. Mass concentration varied between 0.40 and 0.65 mg/m
3
. All 11 markers of lipid oxidation were elevated in production workers relative to the controls (p < 0.001). A significant dose-dependent association was found between exposure to TiO
2
and markers of lipid oxidation in the EBC. These markers were not elevated in the urine samples. Lipid oxidation in the EBC of workers exposed to (nano)TiO
2
complements our earlier findings on DNA and protein damage. These results are consistent with the oxidative stress hypothesis and suggest lung injury at the molecular level. Further studies should focus on clinical markers of potential disease progression. EBC has reemerged as a sensitive technique for noninvasive monitoring of workers exposed to engineered nanoparticles.
We present a case of the acute intoxication of a 17-year-old patient after ingestion of 6 g of quetiapine in combination with 1 g of lamotrigine. Due to the severe tachycardia, hypertension, and ...prolonged QTc without improvement after standard treatment, the patient was treated with Intralipid 20% intravenous infusion recommended by the Toxicologic Information Centre. After lipid infusion, the QTc rapidly normalised and tachycardia resolved to sinus rhythm. The patient was transferred to psychiatry intensive care on the third day after admission.
Graphical abstract
Study objective Methanol poisoning outbreaks are a global public health issue, with delayed treatment causing poor outcomes. Out-of-hospital ethanol administration may improve outcome, but the ...difficulty of conducting research in outbreaks has meant that its effects have never been assessed. We study the effect of out-of-hospital ethanol in patients treated during a methanol outbreak in the Czech Republic between 2012 and 2014. Methods This was an observational case-series study of 100 hospitalized patients with confirmed methanol poisoning. Out-of-hospital ethanol as a “first aid antidote” was administered by paramedic or medical staff before the confirmation of diagnosis to 30 patients; 70 patients did not receive out-of-hospital ethanol from the staff (12 patients self-administered ethanol shortly before presentation). Results The state of consciousness at first contact with paramedic or medical staff, delay to admission, and serum methanol concentration were similar among groups. The median serum ethanol level on admission in the patients with out-of-hospital administration by paramedic or medical staff was 84.3 mg/dL (interquartile range 32.7 to 129.5 mg/dL). No patients with positive serum ethanol level on admission died compared with 21 with negative serum ethanol level (0% versus 36.2%). Patients receiving out-of-hospital ethanol survived without visual and central nervous system sequelae more often than those not receiving it (90.5% versus 19.0%). A positive association was present between out-of-hospital ethanol administration by paramedic or medical staff, serum ethanol concentration on admission, and both total survival and survival without sequelae of poisoning. Conclusion We found a positive association between out-of-hospital ethanol administration and improved clinical outcome. During mass methanol outbreaks, conscious adults with suspected poisoning should be considered for administration of out-of-hospital ethanol to reduce morbidity and mortality.
Recent trends and advances in electrochemistry with composite solid electrodes (CSEs) are reviewed. Their properties, methods of preparation, pre-treatment, and analytical applications are summarized ...and their advantages and disadvantages are discussed. Special attention is paid to the determination of inorganic and organic compounds important from the point of view of the protection of environment and human health. The review is focused on easily prepared electrodes frequently used in the authors' laboratory and their practical applications. However, some other electrodes and their fields of applications are mentioned as well.
The present pilot study tested the efficiency of nanoTiO2 sunscreen to prevent the oxidative stress/inflammation caused by ultraviolet (UV) radiation using biomarkers in subjects’ blood, urine, and ...exhaled breath condensate (EBC). In addition, the skin absorption of nanoTiO2 was studied. Six identical subjects participated in three tests: (A) nanoTiO2 sunscreen, (B) UV radiation, and (C) sunscreen + UV. The first samples were collected before the test and the second after sunscreen application and/or UV exposure. On day 4, the third samples were collected, and the sunscreen was washed off, and the fourth samples were collected on day 11. The following biomarkers were measured: malondialdehyde, 4-hydroxy-trans-hexenal, 4-hydroxy-trans-nonenal, aldehydes C6-C12, 8-iso-Prostaglandin F2α, o-tyrosine, 3-chlorotyrosine, 3-nitrotyrosine, 8-hydroxy-2-deoxyguanosine, 8-hydroxyguanosine, 5-hydroxymethyl uracil, and leukotrienes, using liquid chromatography-electrospray ionisation-tandem mass spectrometry. Titania was measured using inductively coupled plasma mass spectrometry and TiO2 nanoparticles by transmission and scanning electron microscopy. Sunscreen alone did not elevate the markers, but UV increased the biomarkers in the plasma, urine, and EBC. The sunscreen prevented skin redness, however it did not inhibit the elevation of oxidative stress/inflammatory markers. Titania and nanoTiO2 particles were found in the plasma and urine (but not in the EBC) in all sunscreen users, suggesting their skin absorption.
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