Study of lead phytoavailability for atmospheric industrial micronic and sub-micronic particles in relation with lead speciation

Particles from channelled emissions of a battery recycling facility were size-segregated and investigated to correlate their speciation and morphology with their transfer towards lettuce. Microculture experiments carried out with various calcareous soils spiked with micronic and sub-micronic particles (1650 20 mg Pb kg1) highlighted a greater transfer in soils mixed with the finest particles. According to XRD and Raman spectroscopy results, the two fractions presented differences in the amount of minor lead compounds like carbonates, but their speciation was quite similar, in decreasing order of abundance: PbS, PbSO4, PbSO4$PbO, a-PbO and Pb0. Morphology investigations revealed that PM2.5 (i.e. Particulate Matter 2.5 composed of particles suspended in air with aerodynamic diameters of 2.5 mm or less) contained many Pb nanoballs and nanocrystals which could influence lead availability. The soil– plant transfer of lead was mainly influenced by size and was very well estimated by 0.01 M CaCl2 extractio

Quantification of Sunscreen Ethylhexyl Triazone in Topical Skin-Care Products by Normal-Phase TLC/Densitometry

Ethylhexyl triazone (ET) was separated from other sunscreens such as avobenzone, octocrylene, octyl methoxycinnamate, and diethylamino hydroxybenzoyl hexyl benzoate and from parabens by normal-phase HPTLC on silica gel 60 as stationary phase. Two mobile phases were particularly effective: (A) cyclohexane-diethyl ether 1 : 1 (v/v) and (B) cyclohexane-diethyl ether-acetone 15 : 1 : 2 (v/v/v) since apart from ET analysis they facilitated separation and quantification of other sunscreens present in the formulations. Densitometric scanning was performed at 300 nm. Calibration curves for ET were nonlinear (second-degree polynomials), with R > 0.998. For both mobile phases limits of detection (LOD) were 0.03 and limits of quantification (LOQ) 0.1 μg spot−1. Both methods were validated

Characterization of lead-recycling facility emissions at various workplaces: Major insights for sanitary risks assessment

Most available studies on lead smelter emissions deal with the environmental impact of outdoor particles, but only a few focus on air quality at workplaces. The objective of this study is to physically and chemically characterize the Pb-rich particles emitted at different workplaces in a lead recycling plant. A multiscale characterization was conducted from bulk analysis to the level of individual particles, to assess the particles properties in relation with Pb speciation and availability. Process PM from various origins were sampled and then compared; namely Furnace and Refining PM respectively present in the smelter and at refinery workplaces, Emissions PM present in channeled emissions. These particles first differed by their morphology and size distribution, with finer particles found in emissions. Differences observed in chemical composition could be explained by the industrial processes. All PM contained the same major phases (Pb, PbS, PbO, PbSO4 and PbO·PbSO4) but differed on the nature and amount of minor phases. Due to high content in PM, Pb concentrations in the CaCl2 extractant reached relatively high values (40mgL−1). However, the ratios (soluble/total) of CaCl2 exchangeable Pb were relatively low (<0.02%) in comparison with Cd (up to 18%). These results highlight the interest to assess the soluble fractions of all metals (minor and major) and discuss both total metal concentrations and ratios for risk evaluations. In most cases metal extractability increased with decreasing size of particles, in particular, lead exchangeability was highest for channeled emissions. Such type of study could help in the choice of targeted sanitary protection procedures and for further toxicological investigations. In the present context, particular attention is given to Emissions and Furnace PM. Moreover, exposure to other metals than Pb should be considered

Metal and metalloid foliar uptake by various plant species exposed to atmospheric industrial fallout: Mechanisms involved for lead

Fine and ultrafine metallic particulatematters (PMs) are emitted frommetallurgic activities in peri-urban zones into the atmosphere and can be deposited in terrestrial ecosystems. The foliar transfer ofmetals andmetalloids and their fate in plant leaves remain unclear, although this way of penetration may be a major contributor to the transfer of metals into plants. This study focused on the foliar uptake of various metals and metalloids from enriched PM(Cu, Zn, Cd, Sn, Sb, As, and especially lead (Pb)) resulting fromthe emissions of a battery-recycling factory.Metal and metalloid foliar uptake by various vegetable species, exhibiting different morphologies, use (food or fodder) and life-cycle (lettuce, parsley and rye-grass) were studied. The mechanisms involved in foliar metal transfer from atmospheric particulate matter fallout, using lead (Pb) as a model element was also investigated. Several complementary techniques (micro-X-ray fluorescence, scanning electron microscopy coupled with energy dispersive X-ray microanalysis and time-of-flight secondary ion mass spectrometry) were used to investigate the localization and the speciation of lead in their edible parts, i.e. leaves. The results showed lead-enriched PM on the surface of plant leaves. Biogeochemical transformations occurred on the leaf surfaces with the formation of lead secondary species (PbCO3 and organic Pb). Some compounds were internalized in their primary form (PbSO4) underneath an organic layer. Internalization through the cuticle or penetration through stomata openings are proposed as two major mechanisms involved in foliar uptake of particulate matter

Influence of cardiopulmonary bypass on the erythrocyte membranes and the method of its protection

The damage to erythrocytes during cardiopulmonary bypass (CPB) remains a recent problem. The aim of this research was to study the effect of fructose-1,6-diphosphate on the state of the erythrocyte membrane during CPB and the level of phosphorus in blood as a marker of the energy potential in the cell. Patients were divided into two groups. The control group 1 (Gr&nbsp;1) consisted of 75 individuals. The group&nbsp;2 (Gr&nbsp;2) included patients to whom fructose-1,6-diphosphate (FDP) was administrated according to the developed scheme as follows 10&nbsp;g of the drug was diluted in 50 ml of a solvent, 5&nbsp;g of the drug was injected intravenously with the use of perfusor immediately before initiation of CPB at a rate of 10&nbsp;ml/min and 5 g at the 30th minute of CPB (before the stage of warming) the same way. When comparing two groups the best results in hemolysis (p&lt;0.01), mechanical (p&lt;0.01). osmotic resistance of erythrocytes (p&lt;0.01), the time of acid hemolysis (p&lt;0.01) and the permeability of the erythrocyte membrane in postperfusion period were in Gr&nbsp;2. Вefore cardiac surgery hypophosphatemia was detected in 18% out of 150 and in 32% out of 150 patients – a lower limit of normal phosphorus content in the blood. After CPB in Gr&nbsp;1 phosphorus content in blood was 0.85±0.32&nbsp;mmol/l and hypophosphatemia was in 53% out of 75 patients. This indicates a pronounced energy deficit in this group. In Gr&nbsp;2 phosphorus level was 1.7±0.31&nbsp;mmol/l and there was no hypophosphatemia. As a result, FDP as an endogenous high-energy intermediate metabolite of the glycolytic pathway leads to resistance to hemolysis, protects the erythrocyte membrane from damage and increases the energy potential of the cell during CPB

Experimental and theoretical investigation on conformational and spectroscopic properties of dimethyl dithiodiglycolate, [CH3OC(O)CH2S]2

Dimethyl dithiodiglycolate (DTG), [CH3OC(O)CH2S]2, was synthetized by complete oxidation of methyl thioglycolate (MTG) with I2, and characterized by gas chromatography coupled with electron-impact mass spectrometry. Fifteen stable conformers were found with the B3LYP/6-31 + G* approximation, with calculated populations at ambient temperature higher than 1%. The IR and Raman spectra of liquid DTG were interpreted for the first time, in terms of equilibrium between four conformers. The UV–visible spectra of DTG in solutions of ethanol, isopropanol and acetonitrile present a low-intensity band around 230 nm, interpreted mainly as arising from n → π* transitions localized at the C[dbnd]O groups, according to the prediction of TD-DFT calculations.Fil: Juncal, Luciana Celeste. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Química Inorgánica ; ArgentinaFil: Bava, Yanina Belén. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Química Inorgánica ; ArgentinaFil: Tamone, Luciana Mariel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Química Inorgánica ; ArgentinaFil: Seng, Samantha. Université de Lille 1 Sciences et Technologies; FranciaFil: Tobón, Yeny A.. Université de Lille 1 Sciences et Technologies; FranciaFil: Sobanska, Sophie. Université de Lille 1 Sciences et Technologies; FranciaFil: Picone, Andrea Lorena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Química Inorgánica ; ArgentinaFil: Romano, Rosana Mariel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Química Inorgánica ; Argentin

<em>Histoplasma capsulatum</em> and <em>Histoplasmosis:</em> Current Concept for the Diagnosis

Histoplasmosis is a global deep mycosis caused by Histoplasma capsulatum (Hc), a dimorphic fungus. It exists on two main varieties Hc capsulatum and Hc duboisii that could be distinguished by their epidemiology, their clinical presentation, and the morphological aspect of the fungus at direct examination of the sample. Laboratory diagnosis of Hc remains a real challenge as it required experience and equipment. Through a general review of literature, the different diagnosis tools for Histoplasma sp. are analyzed, and strengths and weaknesses are pointed according to the context-based value. Isolation of Hc on culture is the gold standard for diagnosis of histoplasmosis. However, it remains less sensitive (sensitivity: up to 77%) and implies long time to result, which can be inappropriate or in adapted for an emergency diagnosis. So, nonculture methods as antigen testing, serology, and molecular biology become available and allow a rapid diagnosis. However, the optimal diagnostic method depends on many parameters as the very wide range of symptomatology, the immune status. Indeed, Ag detection is the best diagnosis tool for PHD (sensitivity: 92–95%) and SCN histoplasmosis (sensitivity: 66%) and serology for the subacute/chronic form (sensitivity: 85–93%). Thus, the clinico-biological dialog is essential, and histoplasmosis management includes an integrated medical approach