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Comparison of concentrations of toxic elements in the hair of first-year students of RUDN University from different regions of the world: a cross-sectional study
2022
Galchenko, Alexey Vladimirovich | Sidorova, Elizaveta Ilinichna | Sherstneva, Anastasia Alekseevna | Skalny, Andrew Anatolevich | Lobanova, Julia Nikolaevna
Due to the development of the metallurgical and energy industries and the operation of incinerators, more and more environmental pollution is occurring. Toxic elements accumulate in the biosphere and affect the state of the population of the regions of large-scale production or the disposal of industrial waste. The main goal of this study was to compare the toxic elements hair composition in people from different regions of the world. The concentrations of toxic and potentially toxic elements (Al, As, Be, Cd, Hg, Pb, Sn) in 198 people, first-year students of People’s Friendship University of Russia, who arrived from different regions of the world, were measured with inductively coupled plasma mass spectrometry. Students were divided into 6 groups: from South and East Asia, from Latin America, from Arab countries, Central Asia and Afghanistan, from South and Central Africa, from Iran and Azerbaijan, and from Russia, Ukraine, and Moldova. Medians of the concentrations of elements in the hair in the general group were 5.8 μg/g for Al, 30 ng/g for As, 0.6 ng/g for Be, 9.0 ng/g for Cd, 0.11 μg/g for Hg, 0.24 μg/g for Pb, and 0.11 μg/g for Sn. All these values fall within the normal range. Students from Russia, Moldova, and Ukraine showed a significantly higher Sn content (0.28 μg/g) in their hair than subjects from other regions except for Latin America, p<0,05. Except for As, cases of exceeding their recommended concentrations in the hair were identified. However, the proportion of subjects with deviations in each group was not high — not more than 7%. In all regions, a positive correlation was found between Cd, Pb, and Sn, p<0.05, r>0.5 for all. Cases of exceeding the maximum permissible concentrations of various toxic elements in the hair were detected in people from all regions of the Earth included in the study. And although the overall picture of the content of toxic elements in the hair of students from all regions in our study does not look critical, the results of previous studies, as well as information about the total deterioration of the environmental situation throughout the Earth, necessitate further large-scale environmental studies.
显示更多 [+] 显示较少 [-]Environmental Kuznets curve in Southeastern Europe: the role of urbanization and energy consumption
2021
Verbič, Miroslav | Satrovic, Elma | Muslija, Adnan
This paper investigates the dynamic short-term and long-term relationships among real GDP per capita, energy consumption, urbanization, and carbon dioxide emissions within the framework of the environmental Kuznets curve (EKC) hypothesis for Southeastern Europe (SEE) from 1997 to 2014. The evidence highlights an inverted U-shaped nexus between real GDP per capita and carbon dioxide emissions (i.e., the EKC hypothesis is verified in the long-run in the sample as a whole). The short-run estimates provide evidence of inverted U-shaped EKC only for Greece and Moldova. Two-way causal relationship between urbanization and pollutant emission was also established in the short-run, as well as one-way causality flowing from real GDP per capita to pollutant emission. The coefficients with the real GDP per capita and energy consumption are negative and statistically significant in the long-term. These findings indicate the existence of an error correction mechanism that drives the observed variables back to their equilibrium. Moreover, the findings show that the consistent increase in energy consumption has not reduced environmental pressures.
显示更多 [+] 显示较少 [-]Panel estimation for renewable and non-renewable energy consumption, economic growth, CO2 emissions, the composite trade intensity, and financial openness of the commonwealth of independent states
2018
Rasoulinezhad, Ehsan | Saboori, Behnaz
This article investigates the long-run and causal linkages between economic growth, CO₂ emissions, renewable and non-renewable (fossil fuels) energy consumption, the Composite Trade Intensity (CTI) as a proxy for trade openness, and the Chinn-Ito index as a proxy for financial openness for a panel of the Commonwealth of Independent States (CIS) region including Armenia, Azerbaijan, Belarus, Georgia, Kazakhstan, Kyrgyzstan, Moldova, Russia, Tajikistan, Turkmenistan, Ukraine, and Uzbekistan over the period of 1992–2015. It is the first time that CTI and the Chinn-Ito indexes are used in an economic-pollution model. Employing three panel unit root tests, panel cointegration estimation methods (DOLS and FMOLS), and two panel causality tests, the main empirical results provided evidence for the bidirectional long-run relationship between all the variables in all 12 sampled countries except for economic growth-renewable energy use linkage. The findings of causality tests indicated that there is a unidirectional short-run panel causality running from economic growth, financial openness, and trade openness to CO₂ emissions and from fossil fuel energy consumption to renewable energy use.
显示更多 [+] 显示较少 [-]Dynamics of phosphorus forms in the bottom sediments and their interstitial water for the Prut River (Moldova)
2012
Rusu, Vasile | Postolachi, Larisa | Povar, Igor | Alder, Alfredo | Lupașcu, Tudor
Phosphorus concentration in rivers results from both external inputs and internal loading from the bottom sediments. Seasonal, spatial, and multi-annual dynamics of phosphorus forms in bottom sediments and their interstitial water for the river Prut (Moldova) were evaluated. In order to determine content of total phosphorus in the bottom sediments, fresh (wet) samples were subjected to persulfate oxidation. The content of inorganic phosphorus was determined after acidic oxidation of samples. The amount of organic phosphorus was obtained by subtracting inorganic phosphorus from the amount of total phosphorus. Content of phosphorus forms in interstitial water was determined after centrifugation of fresh (wet) sediments. In general, the shape of dynamics of the amounts of inorganic phosphorus in sediments was close during years 2009, 2010, and 2011, with registered higher contents of this form on the middle course of the river. The spatial dynamics of organic phosphorus is less homogeneous along the Prut River. During 2009, higher amounts of organic phosphorus were recorded on the middle sector. During the spring of year 2010, the content of organic phosphorus in sediments was practically not changed along the river. The ratio of inorganic/organic phosphorus in bottom sediments was similar during the researched years, with the predominance of the inorganic phosphorus being recorded. Also, the increasing tendency of the percentage of organic phosphorus from spring to summer was identified. Generally, appropriate spatial and seasonal dynamics of phosphorus forms in bottom sediments and their interstitial water were recorded, although sometimes with some differences.
显示更多 [+] 显示较少 [-]Environmental exposure of anthropogenic micropollutants in the Prut River at the Romanian-Moldavian border: a snapshot in the lower Danube river basin
2018
Moldovan, Zaharie | Marincas, Olivian | Povar, Igor | Lupașcu, Tudor | Longree, Philipp | Rota, Jelena Simovic | Singer, Heinz | Alder, Alfredo C.
The Prut River, the second longest tributary of the Danube river, was investigated for a wide range of anthropogenic organic pollutants to fill the data gap on environmental contamination in eastern European surface waters. In this study, the occurrence of a wide range of organic pollutants was measured along the transboundary Prut River, between Sculeni and Branza in 2010–2012. Using two different analytical methods, gas chromatography coupled to mass spectrometry and liquid chromatography coupled to high-resolution mass spectrometry, over 300 compounds were screened for and 88 compounds were determined in the Prut River. In general, the chemicals occurred at low levels. At the last sampling site upstream of the confluence with the Danube river at Branza, the highest average concentrations (≥ 100 ng L⁻¹) were determined for the artificial sweetener acesulfame, the pharmaceuticals metformin, 4-acetamidoantipyrene, and 4,4,5,8-tetramethylchroman-2-ol, the antioxidants 2,4-di-tert-butylphenol, 3-tert-butyl-4-hydroxyanisol, and 3,5-di-tert-butyl-4-hydroxy-toluene, the personal care products HHCB (galaxolide), 4-phenyl-benzophenone, and octyl dimethyl-p-aminobenzoic acid, the industrial chemical diphenylsulfone, and the sterol cholesterol. Low concentrations of agricultural pesticides occurred in the catchment. At Branza, the total accumulated load of all measured compounds was calculated to be almost 19 kg day⁻¹. In comparison to the Rhine River, the loads in the Prut, determined with same LC-HRMS method for the same set of analytes, were two orders of magnitude lower. Discharge of wastewater without proper treatment from the city of Iasi in the Jijia catchment (Romania) as well as from the city of Cahul (Moldova) revealed a distinct increase in concentrations and loads in the Prut at Frasinesti and Branza. Thus, an implementation of wastewater treatment capacities in the Prut River basin would considerably reduce the loads of micropollutants from urban point sources.
显示更多 [+] 显示较少 [-]Assessment of copper and zinc levels in fish from freshwater ecosystems of Moldova
2012
Zubcov, Elena | Zubcov, Natalia | Ene, Antoaneta | Bileţchi, Lucia
PURPOSE: The aim of this work was to assess the levels of copper and zinc in fish from the main freshwater ecosystems of Moldova, in relation with species, habitat, age, sex, season, and development stage. METHODS: Fish from Cyprinidae and Percidae families (Cyprinus carpio, Carassius auratus gibelio, Rutilus rutilus heckeli, Abramis brama, Aristichthys nobilis, Hypophtalmichthys molitrix, Sander lucioperca) were collected from Prut and Dniester rivers, Cuciurgan, Dubasari, and Costesti-Stanca reservoirs, and ponds of farms in the Dniester delta. The Cu and Zn content of fish tissues (skeletal muscles, liver, gonads, gills, skin, and scales) was determined by flame atomic absorption spectrophotometer AAS-3, of water by graphite furnace HGA 900 of AAnalist 400. RESULTS: The level of heavy metals accumulation in muscles of immature fish follows their dynamics in water. The highest concentration of zinc was registered in the gonads of mature fish, and of copper—in the liver. The lowest Cu and Zn contents were recorded in the muscles and are in the United Nations Food and Agriculture Organization safety-permissible levels for human consumption. Cu and Zn contents in muscles of fish depend on specimen age. Their level in fish gonads was sharply increasing during pre-spawning period. During the early developmental stages, the metal concentration in fish eggs and larvae varies within wide limits, but the accumulation pattern is similar in the investigated species. CONCLUSIONS: The fish represent one of the most indicative factors for the estimation of trace metals pollution in freshwater systems and this is important not only for monitoring purposes, but also for the fish culture ones.
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