Search results for "Heavy Metal"
showing 10 items of 266 documents
Combination of contamination indices and ecological risk assessment index for evaluation of pollution level in sediments
2021
Abstract Sediments act as the key storehouse of heavy metals (HMs) and play a vital function in the transport and potential discharge of HMs. Lower basins and agricultural areas are frequently inundated with various pollutants from different origins, which are categorized as constant, bioaccumulative, and unsafe pollutants. Moreover, the unrestricted development of urban and rural parts of developing countries has a great influence on water quality and ultimately on sediments. The human contributions to HM pollution and allied ecological and health risks are discussed in this chapter. Also in this chapter, details of the single pollution indices and multiple pollution indices are described.…
Distribution of Heavy Metals in Marine Sediments of Palermo Gulf (Sicily, Italy)
2008
Concentrations of Cr, Cu, Hg, Pb and Zn have been measured, by atomic absorption spectrophotometry, in the fine fraction (<63 μm) of surface sediments collected in 30 sites in the Palermo Gulf (Sicily, Italy) in order to assess the levels and the spatial distribution of these elements. Enrichment factors calculated with respect to clean areas have been considered to discriminate between levels due to background or to pollution contributions. The sampling stations, which form a grid inside these areas, are characterized by geographic proximity and by the presence of pollution sources. Ratio matching technique along with hierarchical clustering, minimum spanning tree and principal component a…
Cyclic influences on the heavy metal chronology in a Central Mediterranean area (Palermo Gulf, Italy)
2010
PurposeThe evaluation of long-term heavy metal concentrations in the Gulf of Palermo (Italy) has been carried out in order to investigate how changes of pollution levels in the last 50 years can be reflected in marine sediments. Measurements of Cr, Cu, Hg, Pb, and Zn concentrations were performed on dated fractions of a sediment core. Time series analysis has allowed to obtain information on the chronology of the heavy metal pollution of the area and to identify seasonal components and trends.Materials and methodsHeavy metal concentrations in the <63 μm fraction of core sections were obtained by Atomic Absorption Spectrophotometry, after wet sieving, drying, and digestion procedures. Dating…
Characteristics of current roadside pollution using test-monitoring plots
2014
Abstract The aim of the study was the qualitative recognition of the existing roadside pollutants deposited in topsoils located close to roads with high traffic volume. So far, the studies have helped to determine the content of pollutants that accumulated over a long period of time. Traditionally, it has been difficult to distinguish between roadside pollution and pollution from other industrial sources. In order to avoid such problems and to accurately recognize present threats originating from road traffic, test-monitoring plots were installed in Poland (Gliwice and Opole), Germany (Tubingen, Ulm and Boblingen), Finland (Helsinki), Tajikistan (Dushanbe) and China (Lanzhou). To install th…
Multidisciplinary Approach for Evaluating the Geochemical Degradation of Building Stone Related to Pollution Sources in the Historical Center of Napl…
2020
Natural stones have represented one of the main building materials since ancient times. In recent decades, a worsening in degradation phenomena related mostly to environmental pollution was observed, threatening their conservation. The present work is focused on the minero-petrographic and geochemical characterization of black crust (BC) samples taken from the historical center of Naples, after selecting two pilot monumental areas. The latter were chosen based on their historical importance, type of material, state of preservation and position in the urban context (i.e., high vehicular traffic area, limited traffic area, industrial area, etc.). The building materials used and their interact…
L -lysine and EDTA polymer mimics as resins for the quantitative and reversible removal of heavy metal ion water pollutants
2012
Traditional precipitation methods for inorganic micropollutant removal from waters are increasingly being replaced by sorption methods based on both natural and synthetic materials. In this context, two novel effective heavy metal ions absorbers are presented. These resins, LYMA and LMT85, were crosslinked poly(amidoamine)s carrying amine and carboxyl groups in their repeating units. In particular, the LYMA-repeating unit contains one carboxyl and two amine groups and is a mimic of L-lysine, whereas LMT85 contains two amine and five carboxyl groups and is a mimic of EDTA. Both resins were prepared at moderate cost by simple eco-friendly procedures. The heavy metal ion set adopted as benchma…
Sorption of Cadmium and Zinc in Selected Species of Epigeic Mosses
2014
The sorption abilities of seven moss species growing on the area of Bory Stobrawskie forest (southern Poland) were tested in laboratory. Sorption was carried out in solutions of Zn and Cd chlorides. It has been shown that the sorption properties depend on the moss species and increases in the series as follows: Polytrichum commune < Leucobryum glaucum < Eurhynchium praelongum < Thuidium tamtariscifolium ≤ Dicranum scoparium ≤ Pleurozium schreberi < Sphagnum sp. With help of microscope images, it was also demonstrated that one of the factors affecting the sorption properties of mosses was the level of their surface development. The determined sorption capacity of Zn varies according to speci…
Chemistry, mineralogy and radioactivity inposidonia oceanicameadows from North-Western Sicily
2004
This paper presents measurements of major, minor, metal trace elements and radionuclides in sediments and in Posidonia oceanica samples from north-western Sicily (Italy). The mineralogical and chemical composition of sediments were determined by X-ray diffraction and X-ray fluorescence techniques, respectively. A flame atomic absorption spectrophotometry was used to measure concentrations of Cu, Zn, Cd and Pb in P. oceanica samples and in sediments. Specific activities of selected radionuclides have been determined by high-resolution gamma spectrometry. Standard statistical analysis was used to assess correlations between different elements and different sample types.
Heavy Metals and Human Health: Possible Exposure Pathways and the Competition for Protein Binding Sites
2021
Heavy metals enter the human body through the gastrointestinal tract, skin, or via inhalation. Toxic metals have proven to be a major threat to human health, mostly because of their ability to cause membrane and DNA damage, and to perturb protein function and enzyme activity. These metals disturb native proteins’ functions by binding to free thiols or other functional groups, catalyzing the oxidation of amino acid side chains, perturbing protein folding, and/or displacing essential metal ions in enzymes. The review shows the physiological and biochemical effects of selected toxic metals interactions with proteins and enzymes. As environmental contamination by heavy metals is one of the most…
Toxicogenomics for the prediction of toxicity related to herbs from traditional Chinese medicine.
2010
Toxicogenomics represents the integration of genomics and toxicology to investigate the interaction between genes and environmental stress in human health. It is a scientific field that studies how the genome is involved in responses to environmental stressors and toxicants. The patterns of altered gene expression that are caused by specific exposures or disease outcomes reveal how toxicants may act and cause disease. Nowadays, toxicogenomics faces great challenges in discriminating the molecular basis of toxicity. We do believe that advances in this field will eventually allow us to describe all the toxicological interactions that occur within a living system. Toxicogenomic responses of a …