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Diverse forms of mercury (Hg) have various effects on animals and humans because of a variety of routes of administration. Inorganic mercury (iHg) binds to thiol groups of proteins and enzymes in one’s body or is methylated by microorganisms. Organic form of Hg, contrary to the iHg, is more stable but may be demethylated to Hg2+ in the tissue of intestinal flora. Selenium (Se) also occurs in a variety of chemical forms in one’s body but both of these elements behave very differently from one another. Mercury binding to selenide or Se-containing ligands is a primary molecular mechanism that reduces toxicity of Hg. Complexes formed in such a way are irreversible, and thus, biologically inactive. Se deficiency in a human body may impair normal synthesis of selenoproteins and its expression because expression of mRNA may be potentially regulated by the Se status. This paper provides a comprehensive review concerning Hg–Se reciprocal action as a potential mechanism of protective action of Se against Hg toxicity as well as a potential detoxification mechanism. Although interactions between Hg–Se have been presented in numerous studies concerning animals and humans, we have focused mainly on animal models so as to understand molecular mechanisms responsible for antagonism better. The review also investigates what conclusions have been drawn by researchers with respect to the chemical species of Se and Hg (and their relationship) in biological systems as well as genetic variations and expression and/or activity of selenoproteins related to the thioredoxin (thioredoxin Trx/TrxR) system and glutathione metabolism. Int J Occup Med Environ Health 2018;31(5):575–592
EN
Objectives Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) has considerable applicative potential for both qualitative and quantitative analyses of elemental spatial distribution and concentration. It provides high resolutions at pg-level detection limits. These qualities make it very useful for analyzing biological samples. The present study responds to the growing demand for adequate analytical methods which would allow to assess the distribution of nanostructured molybdenum(IV) disulfide (MoS₂) in organs. It was also motivated by an apparent lack of literature on the biological effects of MoS₂ in living organisms. The study was aimed at using LA-ICP-MS for comparing micro- and nanosized MoS2 ditribution in selected rat tissue samples (lung, liver, brain and spleen tissues) after the intratracheal instillation (7 administrations) of MoS₂ nano- and microparticles vs. controls. Material and Methods The experimental study, approved by the Ethics Committee for Animal Experiments was performed using albino Wistar rats. This was performed at 2-week intervals at a dose of 5 mg/kg b.w., followed by an analysis after 90 days of exposure. The MoS₂ levels in control tissues were determined with the laser ablation system at optimized operating conditions. The parameter optimization process for the LA system was conducted using The National Institute of Standards and Technology (NIST) glass standard reference materials. Results Instrument parameters were optimized. The study found that molybdenum (Mo) levels in the lungs of microparticle-exposed rats were higher compared to nanoparticle-exposed rats. The opposite results were found for liver and spleen tissues. Brain Mo concentrations were below the detection limit. Conclusions The LA-ICP-MS technique may be used as an important tool for visualizing the distribution of Mo on the surface of soft samples through quantitative and qualitative elemental mapping.
EN
Chromium (Cr) is a very common element. It occurs in 2 oxidation states, Cr(III) and Cr(VI). Although Cr(III) is not considered an element essential for mammals, it raises lots of controversy due to its role in the body. While Cr(III) action should be considered an effect of pharmacological action, Cr(VI) is included in the first group of carcinogens for humans. Moreover, it induces numerous pathological changes in the respiratory, urinary, reproductive and digestive systems. In addition, Cr(VI) is used in many industry branches, causing millions of workers all over the world to be exposed to Cr(VI) compounds. A considerable number of the occupationally exposed individuals are in favor of a deep analysis of the mechanisms of Cr(VI) action and a search for a way to reduce its negative impact on the human body. Numerous reactive oxygen species inducing oxidative stress and causing various damage are produced during Cr(VI) reduction in the cells. A good balance between antioxidants and pro-oxidants can reduce Cr(VI)-induced damage. The influence of vitamins and microelements on the adverse Cr(VI) effects has no systematic research results summary. Therefore, this work focuses on the role of dietary antioxidants such as vitamins and microelements in the prevention of Cr(VI) adverse health effects. Numerous studies have revealed a protective influence of vitamins (mainly vitamins E and C) as well as microelements (especially selenium) on the reduction of Cr(VI)-induced adverse changes. A potential protective effect of these ingredients may be useful in occupational groups that are particularly exposed to Cr(VI). However, more research in this area is required.
EN
Objectives: The method for the determination of As, Al, Cd, Ni, Pb (toxic elements) and Cr, Co, Cu, Fe, Mn, Zn (essential elements) in human urine by the use of Inductively Coupled Plasma Mass Spectrometry (quadrupole ICP-MS DRCe Elan, Perkin Elmer) with the dynamic reaction cell (DRC) was developed. Materials and Methods: The method has been applied for multi-element analysis of the urine of 16 non-exposed healthy volunteers and 27 workers employed in a copper smelter. The analysis was conducted after initial 10-fold dilution of the urine samples with 0,1% nitric acid. Rhodium was used as an internal standard. The method validation parameters such as detection limit, sensitivity, precision were described for all elements. Accuracy of the method was checked by the regular use of certified reference materials ClinCheck®-Control Urine (Recipe) as well as by participation of the laboratory in the German External Quality Assessment Scheme (G-EQUAS). Results: The detection limits (DL 3s) of the applied method were 0.025, 0.007, 0.002, 0.004, 0.004, 0.086, 0.037, 0.009, 0.016, 0.008, 0.064 (μg/l) for Al, As, Cd, Cr, Co, Cu, Fe, Mn, Ni, Pb, Zn in urine, respectively. For each element linearity with correlation coefficient of at least 0.999 was determined. Spectral interferences from some of the ions were removed using DRC-e with addition of alternative gas: methane for cobalt, copper, cadmium, chromium, iron, manganese, nickel and rhodium, and oxygen for arsenic. Conclusions: The developed method allows to determine simultaneously eleven elements in the urine with low detection limits, high sensitivity and good accuracy. Moreover, the method is appropriate for the assessment of both environmental and occupational exposure.
EN
One of the priorities in the field of occupational safety and health in the European Union (EU) is research on dissemination and application of scientific results, which results in changes in legislation on exposure assessment to chemical agents and risk estimation. The aim of this paper is to analyze the EU legislation on exposure assessment and risk estimation to chemical agents based on biological monitoring studies, in the context of workers’ health protection, with reference to the occupational hygiene management system and standard. An analysis was made of the current legal regulations as well as recommendations and guidelines for biological monitoring studies in the assessment of workers’ exposure to selected metals. A comparison was made between the regulations in force in Poland and in EU. The rationale for implementing biological monitoring tools in occupational health prevention as an additional tool to protect workers from chemical agents was evaluated.
PL
Jednym z priorytetów z zakresu bezpieczeństwa i higieny pracy w Unii Europejskiej (UE) są badania dotyczące rozpowszechniania oraz zastosowania wyników badań naukowych. Skutkuje to zmianami w prawodawstwie dotyczącym oceny narażenia na czynniki chemiczne i szacowania ryzyka. Celem pracy jest analiza regulacji prawnych stosowanych w UE dotyczących oceny narażenia i szacowania ryzyka na czynniki chemiczne na podstawie badań monitoringu biologicznego w kontekście ochrony zdrowia pracowników oraz w nawiązaniu do systemu i norm zarządzania higieną pracy. Przeprowadzono analizę obowiązujących przepisów prawnych oraz zaleceń i wytycznych dotyczących prowadzenia badań z zakresu monitoringu biologicznego w ocenie narażenia pracowników. Zestawiono obowiązujące w Polsce przepisy z regulacjami wprowadzonymi w UE. Przeprowadzono ocenę zasadności wdrażania narzędzi monitoringu biologicznego w profilaktyce zdrowia pracujących jako dodatkowego narzędzia służącego ochronie pracownika przed działaniem czynników chemicznych.
EN
This study aims to present a case of acute mercuric chloride poisoning at a potentially lethal dose treated with the antidote – 2,3-dimercapto- 1-propanesulfonic acid (DMPS) and continuous renal replacement therapy (CRRT) combined with CytoSorb. A 21-year-old woman was admitted to a hospital with abdominal pain, vomiting, and suspected gastrointestinal bleeding after taking 5000 mg of mercuric chloride for suicidal purposes. Due to the patient deteriorating general condition and multiple organ damage, on the third day she was transported to the Clinic of Anaesthesiology and Intensive Care (CAaIC), Łódź, Poland. Laboratory tests confirmed features of acute kidney injury and high mercury levels in the blood (1051 μg/l) and urine (22 960 μg/l) – DMPS therapy and CRRT combined with CytoSorb were instituted. Due to nervous system complaints (headache, dizziness), a lumbosacral puncture was performed – the mercury concentration in the cerebrospinal fluid (CSF) was 5.45 μg/l. During a colonoscopy, significant diagnostic abnormalities revealed features of colonic mucosal necrosis. The treatment resulted in a decrease in subjective complaints, decreased mercury levels in biological material, and improved parenchymal organ function. On the 15th day of therapy, the patient was transferred to the primary care center for further treatment. The case confirms the possibility of improvement of patient condition following ingestion of a potentially lethal dose (5 g) as a result of the initiation of appropriate therapy even on the third day. The presence of mercury in CSF confirms that inorganic mercury compounds (mercuric chloride) can pass through the blood-brain barrier after oral ingestion.
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