Potential Ecological Risk and Human Health Risk Assessment of Heavy Metal Pollution in Industrial Affected Soils by Coal Mining and Metallurgy in Ostrava, Czech Republic.

The heavy metal pollution of soils has become serious environmental problem, mainly in localities with high industrialization and rapid growth. The purpose of this detailed research was to determine the actual status of heavy metal pollution of soils and an assessment of heavy metal pollution in a highly industrialized city, Ostrava, with a history of long-term impacts from the metallurgy industry and mining. The ecological risks to the area was subsequently also assessed. The heavy metals Cd, Hg, Cu, Mn, Pb, V, Zn, Cr and Fe were determined in top-soils (0-20 cm) using atomic absorption spectrometry (F AAS, GF AAS) from three areas with different anthropogenic loads. The obtained data expressed as mean metal concentrations were very varied among the sampled soils and values of all analyzed metal concentrations were higher than its background levels. To identify the ecological risk and assessment of soil pollution, various pollution indices were calculated, such as single pollution indices (Igeo, CF, EF, PI) and total complex indices (IPI, PLI, PINemerow, Cdeg, mCdeg, Er and PERI). The identification of pollution sources was assessed using Pearson's correlation analysis and multivariate methods (HCA, PCA/FA). The obtained results confirmed three major groups of metals (Fe-Cr, Pb-Cu and Mn-V). A human health risk was identified in the case of Pb, Cd and Cr, and the HI value of V for children also exceeded 1.

Introducing a soil universal model method (SUMM) and its application for qualitative and quantitative determination of poly(ethylene), poly(styrene), poly(vinyl chloride) and poly(ethylene terephthalate) microplastics in a model soil.

Methods for analysis of microplastic in soils are still being developed. In this study, we evaluated the potential of a soil universal model method (SUMM) based on thermogravimetry (TGA) for the identification and quantification of microplastics in standard loamy sand. Blank and spiked soils (with amounts of one of four microplastic types) were analyzed by TGA. For each sample, thermal mass losses (TML) in 10 °C intervals were extracted and used for further analysis. To explain and demonstrate the principles of SUMM, two scenarios were discussed. The first refers to a rare situation in which an uncontaminated blank of investigated soil is available and TML of spiked and blank soils are subtracted. The results showed that the investigated microplastics degraded in characteristic temperature areas and differences between spiked and blank soils were proportional to the microplastics concentrations. The second scenario reflects the more common situation where the blank is not available and needs to be replaced by the previously developed interrelationships representing soil universal models. The models were consequently subtracted from measured TML. Sparse principal component analysis (sPCA) identified 8 of 14 modeled differences between measured TMLs and the universal model as meaningful for microplastics discrimination. Calibrating various microplastics concentrations with the first principal component extracted from sPCA resulted in linear fits and limits of detection in between environmentally relevant microplastics concentrations. Even if such an approach using calculated standards still has limitations, the SUMM shows a certain potential for a fast pre-screening method for analysis of microplastics in soils.

Toxicity of Diclofenac: Cadmium Binary Mixtures to Algae Desmodesmus subspicatus Using Normalization Method.

Algal test using chlorococcal algae Desmodesmus subspicatus was used to determine single acute toxicity of either diclofenac or cadmium and to assess acute toxicity of their binary mixtures. The test confirmed significant acute toxicity of both diclofenac and cadmium; diclofenac with acute toxicity ErC50 60.44 ± 0.20 mg/L and cadmium with acute toxicity ErC50 2.14 ± 0.02 mg/L. This study of acute toxicity of binary cadmium-diclofenac mixtures confirmed their negative effects on aquatic producers and it also proved influence of the above substances on acute toxicity of their mixtures. Normalization method was applied to predict acute toxicity of binary mixtures composed of chemicals with significantly different acute toxicities. Normalization method used molar ratio (R) of chemicals in binary mixtures as their composition descriptor.

Indices of soil contamination by heavy metals - methodology of calculation for pollution assessment (minireview).

This article provides the assessment of heavy metal soil pollution with using the calculation of various pollution indices and contains also summarization of the sources of heavy metal soil pollution. Twenty described indices of the assessment of soil pollution consist of two groups: single indices and total complex indices of pollution or contamination with relevant classes of pollution. This minireview provides also the classification of pollution indices in terms of the complex assessment of soil quality. In addition, based on the comparison of metal concentrations in soil-selected sites of the world and used indices of pollution or contamination in soils, the concentration of heavy metal in contaminated soils varied widely, and pollution indices confirmed the significant contribution of soil pollution from anthropogenic activities mainly in urban and industrial areas.

Effect of surface and interlayer structure on the fluorescence of rhodamine B-montmorillonite: modeling and experiment.

The surface and interlayer structure of rhodamine B (RhB)-montmorillonite for various guest concentrations has been studied using a combination of X-ray powder diffraction and molecular modeling (molecular mechanics and molecular dynamics) in the Cerius(2) modeling environment. The joint effect of surface and interlayer structure on the fluorescence spectrum has been observed and discussed in relation to the position and orientation of RhB(+) cations with respect to the silicate layer. Structural analysis showed that the surface and interlayer structures are different as to the arrangement of RhB(+) cations, and both of them strongly depend on the guest concentration in the intercalation solution and on the method of preparation. The repeated intercalation of montmorillonite by rhodamine B used in the present work allowed obtaining RhB-montmorillonite in the maximum degree of ion exchange for every sample.

Structure analysis of montmorillonite intercalated with rhodamine B: modeling and experiment.

The intercalation process and the structure of montmorillonite intercalated with [rhodamine B]+ cations have been investigated using molecular modeling (molecular mechanics and molecular dynamics simulations), X-ray powder diffraction and IR spectroscopy. The structure of the intercalate depends strongly on the concentration of rhodamine B in the intercalation solution. The presence of two phases in the intercalated structure was revealed by modeling and X-ray powder diffraction: (i) phase with basal spacing 18 A and with bilayer arrangement of guests and (ii) phase with average basal spacing 23 A and with monolayer arrangement of guests. In both phases the monomeric and dimeric arrangement can coexist in the interlayer space. Three types of dimers in the interlayer structure have been found by modeling: (i) H-dimer (head-to-head arrangement) present in the 18 A phase, (ii) sandwich type of the head-to-tail arrangement (present in the 23 A phase) and (iii) J-dimer (head-to-tail arrangement) present in the 23 A phase. Figure Montmorillonite intercalated with rhodamine B cations. On the left: phase 18 A, bilayer dimeric arrangement of guests (H-dimers). On the right: phase 23 A, monolayer arrangement of guests prepared using intercalation solution with a low concentration of rhodamine B