Search Results (195)

The glass industry contributes to long-term soil contamination. This study assesses the impact of over 150 years of industrial activity and over a century of glassmaking processes in the Serbian Glass Factory in Paraćin. Focusing on potentially toxic elements (PTEs) and polycyclic aromatic hydrocarbons (PAHs), ecological and human health risks were evaluated. Sampling was conducted at 34 locations within the factory area, including 33 soil samples (0–30 cm) and one industrial waste (IW) sample. Soil analyses indicate that Zn, Ni, Cu, and Cd exceeded both the maximum permissible concentrations (MPCs) and remediation values (RVs) in many samples, while As and Hg showed fewer exceedances. Based on the Potential Ecological Risk Index (RI), about 33% of soil samples were moderately to highly polluted, and Cd, Pb, As, and Hg were identified as the main contributors. High levels of PAHs and PTEs reflect the cumulative impact of long-term industrial operations, a historical fire, and secondary sources, including traffic-related emissions from nearby highways. These factors resulted in elevated total carcinogenic risk (TCR) for Ni, Cr, and As. This study highlights soil contamination and associated health risks at the glass factory, emphasizing the need for environmental monitoring and management. Full article

Environmental factors are suspected of triggering rheumatoid arthritis (RA). One such factor is oxidative stress (OS), which is a step in ecotoxin detoxification and a damaging factor. The linkage of ecotoxin-triggered OS with clinical and laboratory RA indices in patients and individuals at the pre-RA stage was studied in patients with early (e) (n = 35) and advanced (a) stages of RA (n = 25) and individuals at pre-RA stages (FDR-First-Degree Relative(s), pre-RA, n = 72) in comparison with 52 healthy individuals without autoimmune and immunoinflammatory diseases in their family history (Controls). Ecotoxins within permissible concentration limits were associated with serum levels of OS markers in all cohorts, including Controls. Serum oxidized low-density lipoprotein (oxLDL) levels in pre-RA and eRA cohorts exceeded Control values. Significant differences were found in anti-oxLDL antibody correlations and OS markers. In pre-RA and both RA cohorts, a relationship was found with regards to serum antibodies to cyclic citrullinated peptide (ACCP) levels. Thus, ecotoxin-induced OS likely triggers pathogenic mechanisms at the pre-RA stage and RA onset. Full article

The Kupa River (Croatia), a tributary of the Danube basin forming part of the Slovenian border, was heavily contaminated with polychlorinated biphenyls (PCBs) between 1962 and 1985 due to improper handling and downstream transport via the Krupa and Lahinja rivers. This study evaluated the occurrence, interspecific distribution, and human health implications of PCBs and polycyclic aromatic hydrocarbons (PAHs) in fish (Northern pike, Common carp, Grass carp, Pike-perch, Wels catfish, Bream, and Chub) from the Croatian Kupa River. PCB concentrations were consistently higher than PAH levels across all species. In 30% of samples, Σ6 non-dioxin-like PCBs exceeded the European Commission maximum permissible level for freshwater fish (125 ng⋅g⁻¹ wet weight). Of the 11 PAHs analyzed, only fluoranthene and pyrene were detected. Self-Organizing Map identified distinct pollutant patterns, with chub showing the highest variability and accumulation. PCB concentrations position the Kupa River among moderately to highly impacted European freshwater systems affected by legacy industrial contamination. Health risk assessment, incorporating updated national consumption data, indicates that long-term, uncontrolled consumption of Kupa River fish may pose risks due to PCB exposure, while PAH-related risks appear negligible. These findings highlight the persistence of legacy PCB pollution and the need for integrated sediment–biota monitoring. Full article

Honey is consumed worldwide for its nutritional and medicinal value, but it can also expose people to toxic metals from environmental contamination. This study analyzes heavy metal levels and assesses health risks using inductively coupled plasma optical emission spectrometry (ICP-OES) in honey collected from three areas in the Kellem Wollega Zone, Ethiopia: Dambi Dollo, Gawo Kebe, and Anafilo. The concentrations followed the order: Zn > Fe > Pb > Mn > Cu > Ni > Cd. Notably, Pb and Cd levels exceeded the WHO/FAO maximum permissible limits. The assessment of non-carcinogenic health risks for adult consumers based on the average daily dose, target hazard quotient, and hazard index indicated that all calculated values were below the critical threshold of 1. This result suggests that honey consumption poses no significant non-carcinogenic risk. In contrast, the estimated target cancer risk and cumulative cancer risk (∑TCR) exceeded safety thresholds, indicating potential moderate lifetime carcinogenic risk from chronic exposure. Likely sources of high metal levels include local mining activities, agricultural inputs, and improper honey storage. Consequently, these findings highlight the need for continuous environmental monitoring, stricter regulations, and improved apicultural practices to ensure honey safety and protect public health. Full article

The Ecuadorian Amazon, particularly in the provinces of Sucumbíos and Orellana, has been heavily impacted by oil activity since the 1970s. In this context, this study analyzed 161 groundwater samples taken from deep domestic wells in both provinces, with the aim of determining the concentrations of total petroleum hydrocarbons (TPH) and their implication on the health of consumers. The results showed that, in Orellana, TPH concentrations ranged between 0.11 and 7.30 mg/L, while in Sucumbíos they varied between 0.13 and 7.45 mg/L. More than 95% of water samples exceeded the maximum permissible limit of 0.2 mg/L for drinking water, according to the quality criteria established by Ecuadorian regulations. These levels of contamination reflect a significant exposure of local communities to health risks. In particular, the study revealed that the consumption of groundwater with high concentrations of TPH can generate non-cancer and carcinogenic risks greater than the levels recommended by the United States Environmental Protection Agency (USEPA). This situation endangers the health of people, especially children, who are the most vulnerable. The findings of this study highlight the urgency of implementing control measures and risk management strategies to mitigate contamination in areas affected by oil activity and protect the health of communities that depend on groundwater in the Amazon region. Full article

The study evaluated the feasibility of using the activated sludge process to treat real wastewater from used oil installations containing petroleum hydrocarbons, boron (B), and adsorbable organic halides (AOX). The aim was to determine the maximum ratio of this wastewater that could be added to the influent without impairing treatment efficiency. Tested shares ranged from 0.50% to 1.90%. An initial 1.30% of the tested share caused process instability, reflected in the elevated total nitrogen (TN) levels in treated wastewater. After reducing the share to 0.50%, an adaptation of the activated sludge was observed, manifested by a decrease in TN concentration to below 15.0 mg N/L. For the most favorable share of 1.60% (0.38 ± 0.10 kg_BOD5/kg_MLSS d, 0.51 ± 0.14 kg_COD/kg_MLSS d), the removal efficiencies of chemical oxygen demand (COD), biochemical oxygen demand (BOD₅), TN, and total phosphorus (TP) were 95.0% ± 1.5, 99.1% ± 0.2, 89.3% ± 2.7, and 94.0% ± 5.0, respectively. Increasing the share to 1.90% decreased treatment efficiency and exceedances of COD, BOD₅, TN, and TP occurred. At this ratio, an increase in ammonium nitrogen (NH4⁺-N) and TN concentrations was observed, indicating the inhibition of nitrification. However, the average concentrations of mineral oil index, AOX and B in the treated wastewater remained within permissible levels throughout the study. Full article

A major factor in worldwide ecological harm is the large quantity of municipal solid waste generated because of rapid industrialization and population growth. Nowadays, there are numerous mechanical, biological, and thermal waste treatment processes that can reduce the amount of landfilled waste. A variety of analytical tests are conducted to evaluate the potential risks that landfills pose to human health and the environment. Among these, laboratory leaching tests are commonly employed to assess the release of specific waste constituents that may become hazardous to the environment. Municipal solid waste (MSW) management poses significant environmental risks due to leachate contamination in bioreactor landfills, where acidic conditions (pH ≈ 5) can mobilize heavy metals. This study evaluates the reliability of leaching tests for biodried reject MSW from CWMC Marišćina, Croatia, by comparing standard EN 12457-1 and EN 12457-2 methods (L/S = 2 and 10 L/kg) with simulations of aerobic degradation using acetic acid (10 g/L) to maintain pH = 5 over 9 days. Waste composition analysis revealed plastics (35%), paper/cardboard (25%), metals (15%), and glass (10%) as dominant fractions. Although the majority of parameters determined through standard leaching tests remain below the maximum permissible limits for non-hazardous waste, simulations under acidic conditions demonstrated substantial increases in eluate concentrations between days 6 and 9: Hg (+1500%), As (+1322%), Pb (+1330%), Ni (+786%), and Cd (+267%), with TDS rising 33%. These results highlight the underestimation of risks by conventional tests, emphasizing the need for pH-dependent methods to predict in situ leachate behavior in MBO-treated waste and support improved EU landfill regulations for enhanced environmental protection. Full article

This study assessed the concentrations and health risks of heavy metals in cabbage (Brassica oleracea) and lettuce (Lactuca sativa) cultivated across three urban land surface temperatures in the Greater Accra Metropolitan Area (GAMA): Atomic (low land surface temperature, LST), Ashaiman (moderate LST), and Korle-Bu (high LST). The objective was to assess the influence of urban land surface temperature on heavy metal accumulation and associated human health risks. Results revealed that arsenic (As) and mercury (Hg) levels were consistently low (≤0.002 mg/kg) and remained below the maximum residue limits (MRLs) at all sites. However, cadmium (Cd), lead (Pb), and nickel (Ni) concentrations exceeded MRLs in both vegetables. Cd ranged from 1.40 ± 0.27 mg/kg (lettuce, Ashaiman) to 3.13 ± 0.99 mg/kg (cabbage, Atomic), while Pb varied between 0.90 ± 0.84 mg/kg (lettuce) and 2.62 ± 1.22 mg/kg (cabbage). Ni concentrations exceeded the permissible limit (0.2 mg/kg) across all LST zones, with the highest at Korle-Bu (0.65 ± 0.07 mg/kg). Cumulative heavy metal concentrations increased significantly (p < 0.005) with rising LST, particularly in cabbage. Noncarcinogenic risk assessment indicated that Cd and Ni were the dominant contributors to human health risk, with target hazard quotients (THQ) and hazard indices (HI) exceeding the safety threshold (HI > 1) for both adults and children, especially in Atomic and Korle-Bu. Children were more vulnerable, exhibiting higher exposure levels. Carcinogenic risk (CR) analysis further identified As, Cd, and Ni as the main carcinogens, with total cancer risk (TCR) values across all sites and age groups exceeding the USEPA acceptable range (1 × 10⁻⁶–1 × 10⁻⁴). The findings suggest that increasing urban temperatures exacerbate heavy metal accumulation in leafy vegetables, posing significant noncarcinogenic and carcinogenic health risks, particularly to children. Full article

The observed shortage of water resources in the western and southern regions of the Russian Federation may soon affect the territory of the Republic of Bashkortostan. An increase in the share of groundwaters can help to solve this problem. To provide the population of the republic with water resources, the groundwater of magnesium–bicarbonate-type from the Kraka ophiolite massifs can be used. The massifs occur on the western slope of the Southers Urals. In this work we studied ultramafic rocks and their influence on the formation of the chemical composition of water. The research area is located in the northern part of the Zilair synclinorium, which occurs within the Central Ural megazone. In terms of hydrogeology, of particular importance to the territory of the synclinorium is the Zilair basin of fracture waters of the second order, which is part of the Uralian hydrogeologic folded zone. The ultramafic rocks from the studied area have consistently high CaO/Al₂O₃ ratios (0.4–1.6), which indicates the widespread development of parageneses with participation of clinopyroxene and a low degree of depletion of the primitive mantle source. Because of the complex geological structure of the area, water samples collected from both water points in the Kraka massifs, and the surrounding Early–Middle Paleozoic rocks were analyzed for major ions using a laboratory method to identify possible hydro-geochemical zoning. A statistical analysis was then conducted based on the obtained anion–cation composition data. From the viewpoint of the hydrolytic concept, the formation of the chemical composition of groundwater takes place due to the removal of Mg²⁺ from the rock-forming minerals of ultramafic rocks (olivine and pyroxene) and the supply of Na⁺, K⁺, Ca²⁺, and SO₄²⁻ Cl⁻ from atmospheric precipitations. The bicarbonate anion has a complex nature, where both biochemical processes in the soil and atmospheric precipitation play a significant role. Magnesium–bicarbonate-type of waters, due to low mineralization (to 1 g/L) and the majority of other geochemical parameters (pH of the medium, and content of Na, K, Ca, SO₄, and Cl), whose values that are within the limits set by the World Health Organization (WHO), can be used as drinking water. The increased values of total hardness (0.20–3.39 mmol/L) in accordance with the regulatory document SanPiN 1.2.3685–21, adopted by the Russian Federation, do not exceed the maximum permissible concentrations (up to 7.00 (10.00) mEq/L or 3.50 (5.00) mmol/L). The high magnesium content, in accordance with GOST (state standard) R 54316–2020, allows the magnesium–bicarbonate waters of the Kraka massifs to be classified as table mineral waters for the treatment of various diseases (including hypomagnesemia). Full article

Yerba mate is a popular infusion originating in South America (Brazil, Argentina, Paraguay, and Uruguay). The leaves and shoots of the Paraguayan holly (Ilex paraguariensis A.St.-Hil.), which are used to prepare the drink, contain numerous macro- and microelements. Their content in the plant depends on a number of factors, such as soil mineral composition, cultivation methods, and climatic conditions. The aim of this study was to assess the elemental composition of yerba mate products with respect to their geographical origin. The dried plant and infusions were analysed using flame atomic absorption spectrometry and UV-Vis spectrophotometry for the content of 14 elements (Ca, Na, K, Mg, Cu, Cd, Co, Ni, Mn, Zn, Fe, Cr, Pb, and P). The most abundant macroelement in all analysed products was potassium (K) (1350 ± 167 mg/100 g). Yerba mate from Uruguay contained the highest levels of the analysed macroelements. The highest concentration among microelements was determined for Mn (135 ± 18.4 mg/100 g), for which the highest percentage of the daily requirement was also achieved as a result of consuming 200 mL of the infusion Products originating from Brazil and Paraguay exceeded the maximum permissible level of cadmium (Cd, 0.04 mg/100 g) in dried yerba mate, as specified by the Brazilian Health Regulatory Agency (ANVISA). Multivariate chemometric techniques enabled the differentiation of yerba mate samples according to their geographical origin. Full article

This study represents comprehensive research that arises from the advanced sorption properties of zwitterionic resin beads, which were tested on simulated mono- and multicomponent heavy metal ion (HMI)-polluted water, compared to the stream collected in the Tarnita mine area. Ionic exchange resins (IExRs) were first synthesized in cationic form from a highly crosslinked (8%) acrylic copolymer, by introducing different side groups containing amino functionalities, such as ethylenediamine, triethylenetetramine, and hydrazine hydrate. The corresponding zwitterionic form of each IExR was obtained by reacting the cationic resins with sodium chloroacetate. The structures and morphologies of the synthesized resins were characterized using scanning electron microscopy and infrared spectroscopy. Successful removal of Cu(II), Fe(II), and Mn(II) was quantified by using atomic absorption spectroscopy. Tests with multicomponent synthetic solutions revealed the following typical order of retention: Cu(II) > Fe(II) > Mn(II). In the case of water samples collected from the Tarnita area, the zwitterionic resins were able to retain approximately 93.8% Mn(II), 94.7% Fe(II), and >95.5% Cu(II); in all instances, the concentration of Fe(II) was significantly higher than that of Cu(II) and Mn(II). Additionally, sorption isotherms, kinetics, and thermodynamic parameters were studied. Wheat germination was included to test the efficiency of the batch sorption using IExRs, compared to the stream collected from Tarnita, highlighting how the water cleaning process leads to healthy plant growth. The results demonstrate that, after IExRs sorption the tested HMIs content is below the permissible maximum level for surface water, effectively mitigating the pollution of the steam near to the Tarnita closed mine area, removing the main contaminants found in it. Full article

This study provides a comprehensive assessment of the geoecological status of selected mountain rivers in the North-Eastern Caucasus—specifically, the Sunzha, Sulak, Ulluchay, Karachay, and Atachay—through an analysis of chemical element concentrations, including heavy metals (HMs), in surface water, suspended particulate matter (SPM), and bottom sediments. The elemental composition was determined using inductively coupled plasma mass spectrometry (ICP-MS) on a PlasmaQuant MS Elite instrument (Analytik Jena, Germany), enabling high-precision quantification of 70 chemical elements. Element concentrations in surface water were compared against regulatory limits (e.g., maximum permissible concentrations (MPCs)) defined in international and national guidelines; concentrations in SPM were assessed relative to global average riverine values; and those in bottom sediments were evaluated with reference to average upper continental crust abundances (Clarke values). To trace potential sources of heavy metals entering the riverine systems, enrichment factors (EFs) were calculated for bottom sediments. The results indicate that surface water, suspended particulate matter, and bottom sediments in the investigated rivers exhibit enrichment in numerous chemical elements to levels exceeding their respective reference values (MPCs, global river means, or crustal Clarke values). Significant regional variations in abiotic parameters were observed. Water temperature ranges were 4.6–28 °C (Russian rivers) and 6.9–13.6 °C (Azerbaijan rivers). The pH of Russian rivers was circumneutral to mildly alkaline (7.12–8.83), whereas Azerbaijani rivers were distinctly alkaline, with values reaching 9.88. Reducing conditions in sediments (Eh as low as −206 mV) were prevalent at several stations across both regions. This enrichment reflects an overall unfavorable geoecological status of the studied river systems. Elevated concentrations of several rare earth elements (REEs), observed across multiple sampling locations, suggest a substantial lithogenic contribution linked to the geological structure of the catchments, including the composition of the drained rocks and the presence of ore-bearing formations. Furthermore, localized increases in the concentrations of key heavy metals—such as copper, zinc, cadmium, arsenic, and mercury—point to anthropogenic inputs, most likely associated with mining operations, industrial activities, or other human-induced sources. Full article

The need for an accurate, rapid, and affordable method for determining nitrite ions arises from their toxic effects on humans at elevated levels in wastewater and drinking water. The electrochemical determination is faster, cheaper, and less labor-intensive. It is based on the study of the electrochemical oxidation of NO₂⁻ ions at different carbon electrodes. In this work, it was established that the cyclic voltammograms for the ISEM-3 graphite electrode have an excellent limit of detection for nitrite ions: 5 × 10⁻⁶ M at pH 3, which makes it possible to determine the NO₂⁻ content below the maximum permissible concentration (6.5 × 10⁻⁵ M) in water. Full article

As the core component of new energy vehicles, the performance of the steering axle will directly affect the overall maneuverability, stability, and safety of vehicle driving. The structural performance indexes of the steering axle of the pure electric vehicle are analyzed by the finite element method, and a reasonable improvement plan is given according to its shortcomings. Firstly, the 3D model of the steering axle is established by SolidWorks (SOLIDWORKS 2023), and the details are simplified appropriately and then imported into the ANSYS (ANSYS2020R2 software) platform for static force analysis and modal analysis. Then, the stress distribution, deformation, and the first six orders of intrinsic frequency values of the steering axle are calculated and analyzed by using four working conditions, such as regular driving, emergency braking, lateral slip, and uneven road excitation, and it is concluded that the maximum stress of the original structure under each working condition is less than the requirement of the ultimate stress value. However, from the results, the maximum stress value is concentrated in the emergency braking condition and appears in the intermediate beam corner and the steering knuckle journal, which is also the most dangerous condition. In the modal analysis, it is concluded that the intrinsic frequency of this symmetry structure is much larger than the excitation frequency, and it can produce better dynamic effects under the working conditions, and the dynamic performance is better. Based on this, combined with the results of the static analysis of the proposed new increase in the thickness of the intermediate beam to improve the structural strength of the improvement measures, for this symmetry structure, through the re-simulation of the effect of the most critical conditions (emergency braking), the maximum deformation of the steering axle has been greatly reduced. In addition, the overall stiffness of the symmetry structure has been greatly improved, while the maximum stress is still less than the value of the permissible stress range, and the modal characteristics of the structure has not been affected. The finite element analysis software can effectively evaluate the performance and improve the optimization of the steering axle, which has certain theoretical significance and engineering reference value. Full article

This study examines the impact of an unintended fire at the Drava International plastic processing facility near Osijek, Croatia, on soil quality and the potential human health risks associated with agricultural soils within a 10 and 20 km radius. Surface soil samples (0–5 cm) were collected from ten locations within 10 km three days after the incident, and eight composite samples were taken from sites 10–20 km away 17 days’ post-event. Additionally, 18 control samples previously collected for soil fertility or quality monitoring were included for comparative analysis. In total, 36 agricultural soil samples were analyzed for pH, organic matter, total phosphorus, potassium, calcium, magnesium, and trace elements (Cr, Co, Ni, Cu, Zn, As, Pb). Eighteen post-fire samples were also analyzed for polycyclic aromatic hydrocarbons (PAHs), dioxins, and perfluoroalkyl substances (PFAS). Ecological risk was assessed using the pollution load index (PLI) and enrichment factor (EF), while human health risk was evaluated through the estimation of incremental lifetime cancer risk (ILCR) and individual carcinogenic risks (CRi) for As, Cr, Ni, and Pb. Results showed that concentrations of dioxins (TEQ LB and UB), dioxin-like PCBs, and non-dioxin-like PCBs in samples within 10 km were either below detection limits or present in trace amounts (4.0 × 10⁻⁶ mg/kg). PFAS compounds were not detected (<0.0005 mg/kg). The total concentration of non-dioxin-like PCBs ranged from 0.0023 to 0.0047 mg/kg, well below the maximum permissible levels. Post-fire contamination profiles revealed consistently higher PAH concentrations in the 0–10 km zone (mean 0.100 mg/kg) compared to the 10–20 km zone (mean 0.062 mg/kg). Twenty PLI values exceeded the threshold of 1 (range: 1.00–1.26), indicating moderate pollution, while the remaining values (PLI 0.82–0.99) suggested no pollution. EF values indicated minimal to moderate enrichment (EF < 2), supporting the conclusion that metal presence was predominantly geological with limited anthropogenic influence. All ILCR values for adults and children remained below the acceptable threshold of 1 × 10⁻⁴, indicating low carcinogenic risk under both pre- and post-fire conditions. CRi values followed a consistent decreasing trend across exposure pathways: ingestion > dermal absorption > inhalation. Full article