Human exposure to nanoparticles (NPs) poses potential health risks that are modulated, for example, by the physico-chemical characteristics of NPs, the exposure route and the dose of NPs. Among 21 workers involved for many years in welding on metal surfaces and the machining of nanocomposites, we investigated the role of NPs in the induction of DNA damage. Blood samples of the exposed subjects were collected before and after their working shifts. The controls (21 individuals without occupational exposer to NPs) were sampled in parallel with the exposed ones. NP exposure concentrations were assessed using stationary and personal monitors. DNA damage, including oxidized bases and strand breaks (DNA-SB), in leukocytes was analyzed using Comet assay. The particles monitoring showed that machining was the dominant source of NPs. When compared with the controls, nanocomposite-exposed workers had significantly increased levels of both DNA damage types. In subjects performing machining, post-shift DNA-SB levels were significantly higher than those pre-shift. In welders, such an effect was not observed. Importantly, in both groups, levels of oxidatively damaged DNA were comparable in the post-shift vs. pre-shift samples. The lack of increased DNA oxidation in the post-shift samples suggests the induction of adaptive processes, probably related to long-term occupational exposure to NPs, that protect the organism against this type of DNA damage. However, despite this observation, the potential negative health impacts associated with NP inhalation cannot be ruled out.
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.
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.
AIM:To investigate the effect of acute (daily) inhalation of nanoparticles (NPs) on the transcriptomic profile of male nanocomposite research workers with a history of long-term exposure (years). MATERIALS & METHODS:Whole genome mRNA and miRNA expression changes were analyzed from blood samples collected before and after machining or welding. Exposure in the work environment was assessed using stationary and personal monitoring. RESULTS:Following PM0.1 exposure, a significant decrease in the expression of DDIT4 and FKBP5, genes involved in the stress response, was detected in exposed workers. In the Machining group, the DDIT4 expression correlated with the exposure dose. Increased levels of miR30-d-5p and miR-3613-5p (both involved in carcinogenesis) in welders were associated with the NP exposure dose, highlighting their potential suitability as inhalation exposure markers. CONCLUSION:The results from this pilot transcriptomic analysis (mRNA and miRNA) indicate that exposure to NPs contributes to immune system deregulation and alters the pathways related to cancer. Therefore, the use of protective equipment, as well as obtaining more data by additional research, is highly recommended.
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.
Aim: Today, there is a lack of research studies concerning human acute exposure to nanoparticles (NPs). Our investigation aimed to simulate real-world acute inhalation exposure to NPs released during work with dental nanocomposites in a dental office or technician laboratory. Methods: Blood samples from female volunteers were processed before and after inhalation exposure. Transcriptomic mRNA and miRNA expression changes were analyzed. Results: We detected large interindividual variability, 90 significantly deregulated mRNAs, and 4 miRNAs when samples of participants before and after dental nanocomposite grinding were compared. Conclusion: The results suggest that inhaled dental NPs may present an occupational hazard to human health, as indicated by the changes in the processes related to oxidative stress, synthesis of eicosanoids, and cell division.
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.
Nanoparticles (NPs) have become an important part of everyday life, including their application in dentistry. Aside from their undoubted benefits, questions regarding their risk to human health, and/or genome have arisen. However, studies concerning cytogenetic effects are completely absent. A group of women acutely exposed to an aerosol released during dental nanocomposite grinding was sampled before and after the work. Exposure monitoring including nano (PM0.1) and respirable (PM4) fractions was performed. Whole-chromosome painting for autosomes #1, #4, and gonosome X was applied to estimate the pattern of cytogenetic damage including structural and numerical alterations. The results show stable genomic frequency of translocations (F-G/100), in contrast to a significant 37.8% (p<0.05) increase of numerical aberrations caused by monosomies (p<0.05), but not trisomies. Monosomies were mostly observed for chromosome X. In conclusion, exposure to nanocomposites in stomatology may lead to an increase in numerical aberrations which can be dangerous for dividing cells.
ObjectivesThis study aims to present an overview of the formal recognition of COVID-19 as occupational disease (OD) or injury (OI) across Europe.MethodsA COVID-19 questionnaire was designed by a task group within COST-funded OMEGA-NET and sent to occupational health experts of 37 countries in WHO European region, with a last update in April 2022.ResultsThe questionnaire was filled out by experts from 35 countries. There are large differences between national systems regarding the recognition of OD and OI: 40% of countries have a list system, 57% a mixed system and one country an open system. In most countries, COVID-19 can be recognised as an OD (57%). In four countries, COVID-19 can be recognised as OI (11%) and in seven countries as either OD or OI (20%). In two countries, there is no recognition possible to date. Thirty-two countries (91%) recognise COVID-19 as OD/OI among healthcare workers. Working in certain jobs is considered proof of occupational exposure in 25 countries, contact with a colleague with confirmed infection in 19 countries, and contact with clients with confirmed infection in 21 countries. In most countries (57%), a positive PCR test is considered proof of disease. The three most common compensation benefits for COVID-19 as OI/OD are disability pension, treatment and rehabilitation. Long COVID is included in 26 countries.ConclusionsCOVID-19 can be recognised as OD or OI in 94% of the European countries completing this survey, across different social security and embedded occupational health systems.
BACKGROUND Sensory deficits can result in limitations regarding how well neuropsychological test findings can be interpreted. Only a few studies have investigated the influence of vision alteration on neuropsychological tests. In 2012 the Czech Republic experienced mass methanol poisoning. Methanol metabolites cause histotoxic hypoxia to the optic nerve. OBJECTIVE In the current study, the effect of the toxic damage on the parts of the visual pathway on visual and non-visual neuropsychological measures was investigated using electrophysiological methods (visual evoked potential (VEP) and optical coherence tomography (OCT) with retinal nerve fibre layer (RNFL) thickness measurement. METHODS 53 individuals who experienced methanol poisoning participated in this research (76% men; ages 24 to 74 years, mean = 43.8±14.6 years; education 11.9±1.4 years). Each participant underwent comprehensive neurological, ophthalmological, and neuropsychological examinations. RESULTS The results of mixed-effect models revealed significant small to a medium association between the Stroop test weak interference and Grooved Pegboard with the left eye global, nasal and temporal RNFL thickness. Also, medium associations between the Finger Tapping test and the Stroop test weak interference and OS temporal RNFL, right eye temporal RNFL, and the latency P1 of VEP in the left eye were significant. CONCLUSION The results of this study found a small to medium association (r = .15- .33; p = .010- .046) between RNFL thickness and cognitive visual test performance. Careful interpretation is suggested regarding results obtained from visual tests of the executive or motor functioning with participants with RNFL decrease or other types of early visual processing damage.
OBJECTIVES Isocyanates are known to induce occupational diseases. The aim of this work was to assess the health effects of exposure to isocyanates and to test the sensitivity of selected parameters for early detection of isocyanate-related allergic diseases. METHODS In total, 35 employees from one factory were tested: 26 workers exposed to isocyanates (exposed group) and nine office workers (control group). All subjects filled in a questionnaire regarding possible health problems. Fractional exhaled nitric oxide (FeNO) and spirometry were measured for each subject at the same time during two consecutive working days. A urine sample was taken for a biological exposure test (BET). RESULTS No significant difference was found between the exposed and control groups for spirometry parameters and FeNO. However, in the exposed group, FeNO was highly elevated (> 50 ppb) in five subjects (all reporting health problems at the workplace, all with normal spirometry and non-smokers). The BET revealed a significant difference (p < 0.001) between the exposed and control groups for 4,4´-methylenediphenyl diamine (MDA) in the urine. CONCLUSIONS Our examination showed the usefulness of the BET in monitoring of workplace exposure to isocyanates and the importance of FeNO in monitoring of allergic inflammation of airways in non-smoking employees with normal spirometry.