A simple and reliable method for the determination of mercury in hair on a rotating gold disk electrode using subtractive anodic stripping voltammetry without removal of oxygen is reported. Voltammetric and microwave parameters were optimized to obtain the best analytical results. Parameters such as supporting electrolyte concentration, influence of chloride in the Hg peak, deposition potential, scan rate, accumulation time, rotation rate, square-wave amplitude, and electrode conditioning were studied. Pressurized microwave-assisted digestion of hair, suitable for the accurate voltammetric determination of Hg, was evaluated using six acid mixtures and several time-power programs. Under the optimized conditions, no interference by copper, cadmium, lead, nickel, manganese, iron, or zinc was found at concentrations corresponding to their occurrence in normal hair. A calibration plot between 6,67 and 46,69 microg/L was linear, with r(2) better than 0.999. The detection limit for a deposition time of 60 s at 254 g was calculated as 1.92 nM (3omega). Validation of the method was demonstrated with the use of a certified reference sample of hair. Eight real samples of hair (four unexposed children and four exposed persons) were also analyzed.
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http://dx.doi.org/10.1385/BTER:103:3:261 | DOI Listing |
Am J Physiol Cell Physiol
January 2025
Laboratoire de Physiopathologie et Régulation des Transports Ioniques, Université de Poitiers, France.
Despite the importance of ocular surface in human physiology and diseases, little is known about ion channel expression, properties and regulation in ocular epithelial cells. Furthermore, human primary epithelial cells have rarely been studied in favor of rat, mouse and especially rabbit animal models. Here, we developed primary human Meibomian gland (hMGEC) and conjunctival (hConEC) epithelial cells.
View Article and Find Full Text PDFJ Hazard Mater
January 2025
State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China; University of Chinese Academy of Sciences, Beijing 100049, China.
Elevated methylmercury (MeHg) exposure poses significant risks to bird health, behavior, and reproduction. Still, the risk of MeHg exposure to forest birds, accounting for over 80 % of the world's bird species, is poorly understood. This study combines Hg isotopes and video analysis, aiming to assess MeHg exposure risks to a forest riverine songbird, the spotted forktail (Enicurus maculatus) from a remote subtropical montane forest.
View Article and Find Full Text PDFJ Expo Sci Environ Epidemiol
January 2025
Department of Environmental Sciences & Engineering, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
Background: Preterm birth (PTB) is a common pregnancy complication associated with significant neonatal morbidity. Prenatal exposure to environmental chemicals, including toxic and/or essential metal(loid)s, may contribute to PTB risk.
Objective: We aimed to summarize the epidemiologic evidence of the associations among levels of arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), mercury (Hg), manganese (Mn), lead (Pb), and zinc (Zn) assessed during the prenatal period and PTB or gestational age at delivery; to assess the quality of the literature and strength of evidence for an effect for each metal; and to provide recommendations for future research.
Materials (Basel)
January 2025
Department of Construction Engineering, University of Córdoba, E.P.S of Belmez, Avenida de la Universidad s/n, E-14240 Córdoba, Spain.
The findings highlight the potential for broadening the use of shell aggregates in construction applications. This research investigated the viability of incorporating milled seashells as fine sand replacements for natural calcareous sand in the production of self-compacting mortar. These results highlight a promising avenue for coastal industries to reduce waste while enhancing the durability of construction materials.
View Article and Find Full Text PDFMaterials (Basel)
January 2025
Guizhou Provincial Architectural Design & Research Institute Co., Ltd., Guiyang 550025, China.
Electrolytic manganese residue (EMR) is a solid waste generated during the production of electrolytic manganese metal through wet metallurgy, accumulating in large quantities and causing significant environment pollution. Due to its high sulfate content, EMR can be utilized to prepare supersulfate cement when combined with Ground Granulated Blast furnace Slag (GGBS). In this process, GGBS serves as the primary raw material, EMR acts as the sulfate activator, and CaO powder, along with trace amounts of cement, functions as the alkali activator.
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