Concentration of heavy metals in various children's herbal tea types and their correlations

This investigation was undertaken to determine the concentrations of cadmium, lead, mercury, zinc, copper and magnesium in six tea types used as children's tea. Six types of tea of different herbal composition used for children's consumption (T1, T2, T3, T4, T5 and T6) were analyzed in three subsequent collections. The analysis of cadmium showed that the concentration was very similar in all types of children's tea, ranging from 0.233 to 0.369 mg/kg. Lead concentrations were in the range of 0.340–1.564 mg/kg without any significant differences. The analysis of mercury detected very low concentration of this metal in all samples (0.002–0.004 mg/kg). In zinc, the values ranged from 36.633 to 71.711 mg/kg, with significant differences (p < 0.001) according to tea type. Copper concentration was 10.089–30.178 mg/kg with the highest value in T4. The concentration of magnesium was significantly higher in tea T1 and T2 (102.311 and 129.422 mg/kg) in comparison with other tea types where the level was 19.811–37.411 mg/kg. The maximum tolerable limit determined by Codex Alimentarius was not exceeded in any sample. In general, correlation analysis detected high positive correlation between cadmium and lead (r = 0.89), cadmium and mercury (r = 0.92) and between lead and mercury (r = 0.77).     

Acrylamide-induced alterations in lungs of mice in relation to oxidative stress indicators

The aim of the experiment was to study the influence of acrylamide (ACR) on major antioxidants in the lungs of Swiss mice. The experiment was conducted on male mice that were 8 weeks old. The mice were exposed to ACR at a single dose of 26 µg per animal, which was administered orally. Mice were anesthetized 3, 24, and 48 h after the ACR gavage. Next, histopathological and biochemical analyses of GSH concentration and the activities of SOD, GPx, and CAT were performed in the lungs. Animals exposed to ACR showed demonstrated symptoms of inflammation in lungs, hypertrophy of bronchiolar epithelium, and hyperplasia of alveolar epithelium. GSH concentration was significantly decreased 3 h after ACR gavage, which was followed by a significant increase 48 h after ACR gavage. Similarly, SOD and GPx demonstrated decreased activities 3 h after exposure to ACR, followed by increased activities 48 h after exposure to ACR. CAT activity was significantly increased 24 and 48 h after exposure to ACR. We conclude that oral exposure of mice to ACR results in alterations of lung microstructure, accompanied by the symptoms of redox imbalance.     

Lead deposited in the cell wall of Funaria hygrometrica protonemata is not stable - A remobilization can occur

The hypothesis that lead (Pb) can be uptake or remobilized from the cell wall (CW) by internalization withlow-esterified pectins (up to 40% - JIM5-P), was studied in tip-growing apical cell of Funaria hygrometrica protonemata. Treatment 4 h with 1 mM PbCl₂ caused marked vesicular traffic intensification and the common internalization of JIM5-P from the CW. Lead bound to JIM5-P was internalized from the CW, together with this compound and entered the protoplast. It showed that Pb deposited in CW is not as safe for plant cell as previously believed.However, pulse-chase experiments (recovering 4 h and 24 h) indicated that CW and its thickenings can function as the final sequestration compartments. In Pb deposition sites, a callose layer occurred. It was localized from the protoplast site, next to Pb deposits separating sequestrated to CW and its thickenings Pb from plasma membrane almost certainly protecting the plant cell from its returning into the protoplast.     

Adsorption of Remazol Red 198 onto magnetic N-lauryl chitosan particles: equilibrium, kinetics, reuse and factorial design

Purpose

The discharge of colored effluents from industries is an important environmental issue and it is indispensable to remove the dyes before the water gets back to the rivers. The magnetic adsorbents present the advantage of being easily separated from the aqueous system after adsorption by positioning an external magnetic field.

Methods

Magnetic N-lauryl chitosan (L-Cht/??-Fe₂O₃) particles were prepared and characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, transmission electron microscopy, and vibrating sample magnetometry. Remazol Red 198 (RR198) was used as a reactive dye model for adsorption on L-Cht/??-Fe₂O₃. The adsorption isotherms were performed at 25°C, 35°C, 45°C, and 55°C and the process was optimized using a 2³ factorial design (analyzed factors: pH, ionic strength, and temperature). The desorption and regeneration studies were performed in a three times cycle.

Results

The characterization of the material indicated that the magnetic particles were introduced into the polymeric matrix. The pseudo-second order was the best model for explaining the kinetics and the Langmuir?CFreundlich was the best-fitted isotherm model. At room temperature, the maximum adsorption capacity was 267?mg?g^?1. The material can be reused, but with a decrease in the amount of adsorbed dye.

Conclusions

L-Cht/??-Fe₂O₃ is a promising material to remove RR198 and probably other similar reactive dyes from aqueous effluents.     

Novel approach for assessing heavy metal pollution and ecotoxicological status of rivers by means of passive sampling methods

In order to study the pollution of fluvial ecosystems, it is necessary to analyze not only the levels of chemical contaminants in water, but also those accumulated in the sediment matrix, as well as to assess its ecotoxicological status. Eleven Catalan (Spain) river sections (one sampling point per river) located near urban and industrial areas were sampled during winter of 2009. Water pollutants were collected by using passive samplers as Diffusive Gradient in Thin-Films (DGTs) and Semi-Permeable Membrane Devices (SPMDs). Point water samples were also collected. The concentrations of potentially toxic elements (PTE) in water, filtered water, DGTs and sediment samples were analyzed. Aqueous and organic solvent extracts of sediments samples and organic extracts of SPMDs were performed to assess acute toxicity to Vibrio fischeri by Microtox(?), and chronic toxicity to the green alga Pseudokirschneriella subcapitata. Microtox(?) test was also performed with DGT extracts. The results show that metals content of Catalan river waters are below the freshwater screening US EPA benchmarks, excepting some industrial areas (for Hg, Pb, and Zn). In contrast, sediments levels of some rivers were far above freshwater sediment screening US EPA benchmarks (for Zn, As, Cr, Pb, Ni, Hg, and Mn), particularly in the most industrialized areas. A good correlation was found between toxicity values of extracts (from sediments and DGTs) and PTE levels in sediments. The current results support the suitability of using combined point and passive sampling methods for assessing the chemical and ecotoxicological status of aqueous environments.     

The immobilisation and retention of soluble arsenic, cadmium and zinc by biochar

Water-soluble inorganic pollutants may constitute an environmental toxicity problem if their movement through soils and potential transfer to plants or groundwater is not arrested. The capability of biochar to immobilise and retain arsenic (As), cadmium (Cd) and zinc (Zn) from a multi-element contaminated sediment-derived soil was explored by a column leaching experiment and scanning electron microanalysis (SEM/EDX). Sorption of Cd and Zn to biochar’s surfaces assisted a 300 and 45-fold reduction in their leachate concentrations, respectively. Retention of both metals was not affected by considerable leaching of water-soluble carbon from biochar, and could not be reversed following subsequent leaching of the sorbant biochar with water at pH 5.5. Weakly water-soluble As was also retained on biochar’s surface but leachate concentrations did not duly decline. It is concluded that biochar can rapidly reduce the mobility of selected contaminants in this polluted soil system, with especially encouraging results for Cd.     

Towards adaptation of agriculture to climate change in the Mediterranean

This study links climate change impacts to the development of adaptation strategies for agriculture on the Mediterranean region. Climate change is expected to intensify the existing risks, particularly in regions with current water scarcity, and create new opportunities for improving land and water management. These risks and opportunities are characterised and interpreted across Mediterranean areas by analysing water scarcity pressures and potential impacts on crop productivity over the next decades. The need to respond to these risks and opportunities is addressed by evaluating an adaptive capacity index that represents the ability of Mediterranean agriculture to respond to climate change. We propose an adaptive capacity index with three major components that characterise the economic capacity, human and civic resources, and agricultural innovation. These results aim to assist stakeholders as they take up the adaptation challenge and develop measures to reduce the vulnerability of the sector to climate change.     

Production of zeolitic materials in pilot scale based on coal ash for phosphate and potassium adsorption in order to obtain fertilizer

Environmental Science and Pollution Research - The use of different types of zeolites (X, Na-P1, and 4A) synthesized by different methods and scales were tested in this work to adsorb nutrients...     

Energy and environment as the foundations for sustainable development

Environmental Science and Pollution Research -