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EN
The objectives of the study were to (1) identify and measure the concentration of five toxic elements in the Tigris water, (2) determine the threat of these metals in water by various pollution indices such as pollution index (PI) as single index, metal index (MI) as integrated index, and potential ecological risk index (PERI) to assess the ecological risk. The results of this study showed that PI values for most elements were at nonaffected levels, except for Pb and Al metals, which were within slight and moderate levels, respectively. Whereas MI values indicate that all sites fall within a threshold of warning level. For the contamination factor, the values mostly lie in the low contamination level, except Al lies within the moderate range, which led to an increase in the contamination degree. For risk assessment, the values of ecological risk factors for all metals at all sites were within a low-risk level, less than 40. Also, the values of the ecological risk index in all sites were at a low-risk level, recorded at 17.70, 22.92, 22.62, and 21.79 in sites 1, 2, 3, and 4, respectively. We can conclude that the decrease in the levels of Er led to a decrease in the levels of PERI and vice versa.
EN
The goal of the research was to evaluate the heavy metal detection and potential ecological risks in lake’s water. Geological formations consisting essentially of sandstone and quaternary marine or dune sands characterize the study area. With a climate of the Mediterranean type winters are mild and humid, whereas summers hot and dry. At the analysis center of the Faculty of Sciences, the monitoring of ETMs is carried out by ICP-MS, the processing of data and the validation of the analysis method have been drafted according to the NF T 90-120 standard applicable to the analysis in a laboratory. The analysis covers concentrations of heavy metals, which include Cu, Zn, Mn, Fe, Pb and As, in the water. Pollution load index (PLI) values were above one (>1) which indicates progressive deterioration of the water quality. However, contamination factor (CF) values of Pb and Cu, ranging from 8.31 to 15.68 and from 5.5 to 28.05 respectively, show that the studied water remains under a strong impact by Pb and Cu. Considering the severity of the ecological risk (Er) for a single metal, the descending order of contaminants is Cu > Pb > Mn > Fe > Zn. In relation to the total ecological risk index (RI), water from the lake shows low to considerable ecological risk.
EN
This study aimed to analyze the heavy metal contamination in sediments and their potential ecological risks. The sediment samples were collected using PVC pipes and grab samplers at nine study sites in Youtefa Bay, namely five sites in the mangrove ecosystem, two sites in the estuary, and two sites in the middle of the bay. The heavy metal content was analyzed using Atomic Absorption Spectrophotometry. The results of the analysis of the heavy metal content in the sediment were in the following order: Zn > Cu > Pb > Ni > Cr > Cd > As > Hg (106.077±98.857, 28.553±30.505, 19.798±11.541, 17.665±11.457, 12.103±0.124, 2.996±1.235, 0.149±0.124, and 0.082±0.047 mg kg-1, respectively). Only the Cd content has exceeded the Threshold Effect Level (TEL) at all study sites. On the other hand, the As and Cr content has not exceeded TEL at any study site. The content of Hg, Cr, Pb, Zn, and Ni has exceeded TEL only at a few study sites. The heavy metal content in estuary sites is higher than in mid-bay and mangrove sites, which can provide the information on the sources of heavy metal contaminants. There is a significant correlation for the content of Cu, As, Pb, Cd, Zn, and Ni which can indicate that the sources of these heavy metals are relatively the same (r = 0.569 to r = 0.950). The CF and Igeo values indicate that there has been contamination of several heavy metals studied. Further analysis ( ERI ) showed that the heavy metal content in the sediments poses a potentially serious ecological risk. Most of the potential ecological risks are the contribution of Cd and Hg which have high toxicity factors and this should receive special attention from local governments and stakeholders to prevent higher contamination.
EN
The aim of this paper was to analyse the impact of long-term operation of a zinc-works on the soil environment based on 20-year observations. The study material comprised the surface soil samples and soil profiles collected in close vicinity of the zinc-works in Miasteczko Śląskie (Southern Poland) and in the locations within certain distance from the plant. The total content of Pb and Zn in the surface soil samples collected in the vicinity of the zinc-works in 2018 ranged from 3,975 to 26,200 mg/kg for Pb and from 3,358 to 21,867 mg/kg for Zn. These values were considerably higher than those recorded 20 years earlier (i.e. 601–11,939 mg/kg and 1,009–13,924 mg/kg for Pb and Zn, respectively). The mineral composition was dominated by quartz, feldspars and carbonates (e.g. calcium carbonate). Additionally, iron hydroxides (lepidocrocite), lead sulphates (anglesite) and zinc silicates (hemimorphite) were found. The bioavailable quantities of Pb and Zn in the soil samples collected in 2018 amounted to 30% of the total content in the case of Pb and 34% of the total Zn content. Twenty years earlier, the mean values were 66% (Pb) and 44% (Zn), respectively. The acidity of the soil samples collected in the vicinity of the zincworks indicated their very good buffering capacity, as well as the capacity to release 58-60% of the total Pb and Zn contents to the environment, with a pH decrease of only 3 units. The Risk Assessment Code (RAC) calculated based on the Pb and Zn cations in the exchangeable positions and bound with carbonates indicates that even after 20 years, there is still a high environmental risk related to the presence of those metals in soils. This paper also demonstrates that presently the major factors contributing to the pollution of soil are deflation and suffosion of small particles from the old, unprotected mining and industrial waste dumps.
EN
The distribution of metals (Pb, Cu, Cd, Ni, Cr, Zn) in surface sediments and the potential pollution sources in the south-eastern part (SE) of the Baltic Sea (Lithuanian zone) were investigated in relation to the environmental characteristics (amount of fine-grained particles, TOC content in sediments, origin of sedimentary organic matter, salinity, water depth) in 2011-2014. The higher metal concentrations were measured in sediments of the Curonian Lagoon and in the open waters. An approach using various environmental indices (enrichment factor EF, geoaccumulation index Igeo and contamination factor CF) was used to quantitatively assess a contamination degree. The principal component analysis (PCA) was applied in order to further scrutinize pollution from metal sources. The values of the contamination indices showed no/very low sediment contamination with Ni and Cr, minor-moderate contamination with Cu, Zn and Pb and moderate-considerable pollution with Cd. The strong relationships among metals suggested their similar distribution pattern and a combination of natural and anthropogenic sources. The higher metal concentrations coincided with an increasing amount of fine-grained fraction and organic carbon. In the territorial waters, the distribution of elements was related to the water depth. In addition, the binding of metals with insoluble iron sulphides might explain their high concentrations at the most remote and deepest stations.
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