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Cadmium (Cd) is an abiotic stressor negatively affecting plant growth and reducing crop productivity. The effects of Cd (25 μM) and of pre‐soaking seeds with salicylic acid (SA) (500 μM) on morphological, physiological, and glycerolipid changes in two cultivars of wheat (Triticum aestivum L. ‘Tosunbey’ and ‘Cumhuriyet’) were explored. Parameters measured were length, fresh and dry biomass, Cd concentration, osmotic potential (ψ), lipid peroxidation, and polar lipid species in roots and leaves, as well as leaf chlorophyll a, carotenoids, and fv/fm. Fresh biomass of roots and leaves and leaf length were strongly depressed by Cd treatment compared to the control, but significantly increased with SA + Cd compared to Cd alone. Cd reduced leaf levels of chlorophyll a, carotenoids, and fv/fm, compared to controls. Treatment with SA + Cd increased pigment levels and fv/fm compared to Cd alone. Cd treatment led to a decrease in DW of total membrane lipids in leaves and depressed levels of monogalactosyldiacylglycerol and phosphatidic acid in leaves and roots of both cultivars. The effects of SA priming and SA + Cd treatment on lipid content and composition were cultivar‐specific, suggesting that lipid metabolism may not be a primary target underlying SA remediation of the damaging effects of Cd on wheat growth and development. [ABSTRACT FROM AUTHOR]

Broad-spectrum veterinary antibiotic tylosin (TYL) is utilized in livestock and poultry. Due of its extensive usage and animal excretion in urine and feces, it affects the environment and human health. For determining the equilibrium time, the adsorption maximum capacity and the optimal isotherm model, adsorption batch tests have been conducted. Sips and Pseudo-second order models had R2 values of 0.9937 and 0.9764, respectively, and best matched experimental isotherm and kinetic data. The maximum TYL uptake onto soil was 2355.08 mg.kg−1. Using fixed bed adsorption experiments, the current study clarifies the issue of soil contamination in conditions that are close to natural phenomena. Fixed bed adsorption tests demonstrated that the inlet TYL concentration, soil bed height, and flow rate, influenced saturation and breakthrough times. Bohart-Adams, Thomas, and Yoon-Nelson models matched the experimental findings well in a variety of conditions. With 100 mg.L−1 concentration, 4 cm bed height, and 5 mL.min−1 flow rate, the maximal bed capacity of 1277.06 mg.kg−1 was achieved with R2 value of 0.9797. Experimental findings also indicated that the adsorption capacity in batch and dynamic tests are of the same range of magnitude. Based on this, tylosin is a probable soil contaminant. [ABSTRACT FROM AUTHOR]

Contamination at shooting ranges is a growing concern due to the accumulation of potentially toxic elements in the soil. The aim of the study was to determine the level of soil contamination in different types of Lithuanian shooting ranges (clay-target, practical, small-bore) and assess the potential ecological risks. Soil samples were taken in two soil layer depths (0–10 cm and 10–30 cm) and locations (range floor and berm/target line) of different types of shooting ranges. The soils of the practical and small-bore shooting ranges were neutral, clay target – slightly alkaline. The soil of the clay-target firing range floor had a significantly lower organic matter, than small-bore and practical firing ranges. Lead contamination was significantly higher in the floor and berm surface soil and subsoil (about 1000 mg kg−1 and 360–527 mg kg−1, respectively) of the practice range compared to the others and controls. The Cd concentrations in the surface soil of the practical range and the small-bore firing ranges and in the soil of the berm were considerably higher than in the soil of the clay target. There was a significant negative correlation between soil pH and Pb and Cd concentrations. Pb content was positively correlated with organic matter content. The soils of the practical range floor and berm indicated high ecological risk. The research showed that heavy metal contamination is specific in different types of shooting ranges, therefore various management practices should be applied to prevent pollution in particular shooting range. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) and heavy metal pollution pose significant environmental threat, potentially leading to agroecosystem toxicity and jeopardizing food security. Therefore, this study aims to evaluate the abundance and risk assessment of these pollutants in five different farmlands of Ernakulam district, India. Results showed that MPs content in agricultural fields near commercialized areas such as Kakkanad Nedungapuzha, Nedumbassery, and Kadamakuddy was dominant compared to Nechoor, a rural area. The average microplastic abundance was found to be 45.6 ± 26.4 items kg⁻1 dw. Polypropylene (PP) and polyethylene (PE) were the dominant polymers found in the soil samples, constituting 45% and 25% of the microplastic content, respectively. The pollution load index of MPs indicates that the sampling sites are considered to be polluted as PLI > 1 with hazard level I. The heavy metal pollution status follows the order: Cu (80.3 to 724 mg/kg) > Zn (77 to 543.5 mg/kg) > Cr (171.65 to 334.65 mg/kg) > As (10.25 to 79.5 mg/kg) > Pb (2.05 to 30.3 mg/kg) > Cd (0.3 to 14.35 mg/kg). Calculated pollution load index (PLI) geo-accumulation index (Igeo), ecological risk assessment values indicate that commercialized regions exhibit high levels of trace metals, namely Cu, Zn, As, Cd, and Cr, posing a significant concern for the agricultural ecosystem. Our results indicate heightened microplastics and heavy metals prevalence in farmlands adjacent to commercial zones, necessitating immediate preventive action to mitigate increasing concentrations. [ABSTRACT FROM AUTHOR]

In recent decades, the use of pesticides has become fundamental to agricultural growth. However, the persistent and toxic nature of pesticides has led to significant concerns regarding their ecological and human health consequences. Therefore, for a better understanding of pesticide contamination and its potential risks, here we assessed the levels of five emerging pesticides—acetochlor, imidacloprid, MCPA, atrazine, and allethrin—in soil samples from ponds used for irrigation and in drinking water samples from nearby areas in Lahore, Pakistan. Our findings revealed that 100% of the samples were contaminated, posing substantial ecological and human health risks. Based on the toxic units (TUsum), all the soil samples showed higher toxic pressure, exceeding acute and chronic toxicity thresholds for earthworms, while 100% of water samples posed chronic toxicity risks to crustaceans and 10% to algae. Pollution index (PI) analysis further classified 100% of the soil samples and 10% of the water samples as highly polluted. These findings show high-pesticide residues in both soil and water and highlight immediate risk assessment and mitigation measures to protect non-target organisms. This preliminary information can be used to adopt risk assessment monitoring programmes and help higher authorities in making policies and guidelines to mitigate the escalating risk for ecology and humans. [ABSTRACT FROM AUTHOR]

Accidental fuel spills associated with the storage, transfer, and use of diesel fuel for power generation have occurred on sub‐Antarctic Macquarie Island since the establishment of the island's research station in 1948. An extensive in situ remediation program was implemented by the Australian government from 2009 to 2016 that used nutrient addition and air sparging to enhance the microbial degradation of petroleum products. During this period, a range of ecotoxicological assessments were conducted to better understand the impacts of fuel in soils on native biota and their sensitivity. This study compiles this ecotoxicological data into a species sensitivity distribution (SSD) to establish environmental quality guideline values (EQGVs) for fuels in soils on Macquarie Island. The SSD model includes 13 critical effect concentrations (CECs) selected using an expert judgment approach. These include data from functional and community‐based tests as well as traditional single‐species toxicity tests using microbes, plants, and invertebrates and representing the range of carbon content (~3%–48%) and fuel composition at various stages of degradation (from fresh to 18 months aged) in soils as occurs at contaminated sites on the island. A protective concentration (PC80) of 97 mg/kg TPH C9–C40 (95% CI 24–283) was derived for special Antarctic blend diesel from the SSD and is recommended as an appropriate site‐specific EQGV and potential remediation target for the immediate station area in the vicinity of infrastructure. More conservative PC values are also provided for areas with higher conservation values outside the station footprint. These EQGVs are the first to be produced for fuels in the sub‐Antarctic and Antarctic regions. They will be used to inform ongoing environmental management on Macquarie Island and are likely suitable and recommended for use more broadly across the sub‐Antarctic. Integr Environ Assess Manag 2024;20:2334–2346. © 2024 Commonwealth of Australia. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC). Key Points: This study has produced the first environmental quality guideline value (EQGV) for fuel for the sub‐Antarctic and Antarctic region; a site‐specific PC80 of 97 (24–283) mg/kg total petroleum hydrocarbons for diesel fuels in soils.We use adapted criteria and an expert judgment approach to select 13 toxicity estimates from functional, community, and traditional single‐species toxicity tests using microbes, plants, and invertebrates from Macquarie Island for inclusion in a species sensitivity distribution model.Toxicity data included represent the response of biota to a range of carbon content (3%–48%) and to the composition of fuel at various stages of degradation (from fresh to 18 months aged) in soils as occurs at contaminated sites on Macquarie Island.The methodology for guideline derivation and the EQGVs provided will be integral to the implementation of future cleanup activities across Australia's contaminated sites in the sub‐Antarctic and Antarctic and are recommended for use more broadly across this polar region. [ABSTRACT FROM AUTHOR]

The accurate identification of pollutant sources and their spatial distribution is crucial for mitigating soil heavy metals (SHMs) pollution. However, the receptor model struggles to effectively categorize pollutant sources and pinpoint their locations and dispersion trends. We propose a novel comprehensive framework that combines a receptor model, random forest (RF), affinity propagation (AP) algorithm, and bivariate local indicator of spatial association (BLISA), to optimize the traditional approach for tracing SHMs sources in industrial regions. We apportioned SHMs sources using a receptor model combined with RF, while BLISA combined with AP methods were employed to accurately locate the source areas and identify their dispersion tendencies. The results revealed that SHMs originated from mixed sources of equipment manufacturing agglomeration and agricultural activities (59.0%), geological background (30.5%), and emissions from heavily-polluting industries (10.5%). The pollution sources of soil Cd and Pb were located near specific industries, showing characteristics of multi-site concurrent pollution diffusion influenced by their proximity to industrial sites. The spatial distribution of Cr, Cu, and Zn sources was concentrated in high-density urban industrial areas, transitioning from point to nonpoint sources, with diffusion patterns influenced by the spatial agglomeration effect of industries. Our enhanced framework accurately identifies the location of SHMs sources and their dispersion tendencies, thereby improving regional soil pollution management. [ABSTRACT FROM AUTHOR]

Copper is a trace element in plants and animals whose importance can be understood due to its role in different essential metabolic processes. Anthropogenic activities such as agriculture and mining are potential sources of pollution due to the emission of copper into the environment. Brazilian legislation ties soil quality to guideline values, among which the Prevention Value indicates the critical environmental limit for trace elements. The aim of this study was to obtain PVs for copper for two subtropical soils (Cambisol and Nitisol), given that the pedological richness was not considered when deriving the PVs contained in the federal normative. Reproduction assays followed ISO guidelines with the earthworm species Eisenia andrei and Perionyx excavatus, the enchytraeids Enchytraeus crypticus and Enchytraeus bigeminus and the springtails Folsomia candida and Proisotoma minuta. Results showed that the sensitivity of the organisms was greater in Cambisol. The most sensitive species were the earthworms, especially Perionyx excavatus (EC50 = 67.83 in Cambisol; EC50 = 264.96 in Nitisol). The springtails, on the other hand, were the least sensitive to contamination. These findings reinforce the need to include organisms from different ecological groups in ecotoxicological assessments. It was also observed that the PV adopted in federal legislation (= 60 mg kg−1) is in fact protective for the species and soils we evaluated, since the PVs we obtained based on the EC50 were 346.74 mg kg−1 in Nitisol and 134.05 mg kg−1 in Cambisol. It is important to note that our results do not exclude the need for evaluations with other subtropical soils, given the influence of their properties on the toxicity and bioavailability of copper to soil organisms. [ABSTRACT FROM AUTHOR]

Understanding the fine‐scale spatial distribution of heavy metal contamination is crucial for effective environmental capacity control and targeted treatment of polluted areas. This article presents the latest dataset on the occurrence of common heavy metals in the soils of the Yangtze River Basin. The dataset was compiled by reviewing peer‐reviewed literature published between 2000 and 2020. Rigorous quality control procedures were employed to ensure the accuracy of the data, including the extraction of detailed geographic locations and concentrations of heavy metals. The dataset includes 7867 records of heavy metal occurrences (Zn: 1045, Cu: 1140, Pb: 1261, Cr: 980, Cd: 1242, Ni: 649, As: 821, Hg: 729) in the soils of the Yangtze River Basin, distributed at four scale levels: province, prefecture, county, and township or finer. The results indicate that the distribution of heavy metal concentrations is relatively scattered, with higher concentrations in cities and regions with developed industry and agriculture. Cd has the highest exceedance rate (33.90%), indicating significant local contamination. Heavy metals, such as Zn at 11.96%, Ni at 12.63%, and As at 9.74%, also exceeded standard levels at certain sampling points. Cr had the lowest exceedance rate of 1.33%. This updated dataset provides essential information on the current status of heavy metals contamination in the soils of the Yangtze River Basin. It can be used for further ecological and health risk assessments and for developing strategies to remediate and prevent heavy metal contamination in the region. [ABSTRACT FROM AUTHOR]

This study aims to assess the extent of hydrocarbon and heavy metal contamination in soils from specific areas on Azerbaijan's Absheron Peninsula, including Absheron, Suraxanı, and Baku, and to evaluate the impact of this contamination on soil properties. Soil samples were analyzed for Total Petroleum Hydrocarbons (TPH) and heavy metals, including aluminum, arsenic, cadmium, lead, and iron, alongside assessments of soil physical, chemical and biological properties. The results revealed significant contamination across all studied areas, particularly in Suraxanı, where TPH levels reached 190 ± 20 mg/kg, exceeding the environmental standard of 100 mg/kg. Similarly, Suraxanı soils exhibited alarmingly high concentrations of heavy metals, with aluminum at 30,128 ± 1,500 mg/kg, arsenic at 50.94 ± 2.5 mg/kg, and cadmium at 0.153 ± 0.01 mg/kg, all surpassing acceptable limits. These contaminants severely degraded soil health, evidenced by increased bulk density (1.7 g/cm³ in Suraxanı) and reduced soil porosity. Microbial activity, a key indicator of soil fertility, was also markedly lower in contaminated regions, with the total bacterial count in Suraxanı being less than half that of the uncontaminated area. The findings underscore the urgent need for comprehensive soil management practices and stricter environmental regulations to mitigate contamination's adverse effects and protect both ecosystems and public health in Azerbaijan's petroleum contaminated areas. [ABSTRACT FROM AUTHOR]

Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) are ubiquitous in the environment. The main route of human exposure is through food consumption. Soil contamination can be problematic for sanitary safety depending on the usage of the soil, such as farming. In case of environmental soil contamination with PCDD/Fs, hen's eggs may be contaminated due to soil ingestion by hens. For this reason, it is important to understand the parameters that influence eggs' contamination when hens are raised in contaminated areas. After the discovery of a contaminated area in Lausanne (Switzerland), we collected hens' eggs from ten domestic-produced eggs and one farm. Based on PCDD/F measurements of eggs and soil, and a toxicokinetic model, we estimated individual hen's soil intake levels and highlighted appropriate parameters to predict the dose ingested. Recommended weekly consumption for home-produced eggs was calculated based on the tolerable weekly intake proposed by EFSA in 2018. The most important parameter to assess the soil ingestion does not seem to be the soil coverage by vegetation but rather the hen's pecking behaviour, the latter being difficult to estimate objectively. For this reason, we recommend using a realistic soil ingestion interval to assess the distribution of egg PCDD/F concentration from free-range hens reared on contaminated soil. The addition of soil contamination in the toxicokinetic model can then be used to recommend to the general population weekly consumption of eggs. The consumption by adults of free-range eggs produced on land with soil containing >90 ng toxic-equivalent (TEQ)/kg dry soil should be avoided. Even with a low level of soil contamination (1–5 ng TEQ/kg dry soil), we would recommend consuming not more than 5 eggs per week for adults and no more than 2 eggs for children below 4 years old. [ABSTRACT FROM AUTHOR]

This study investigates the phytoremediation potential of non-productive seedlings of Ailanthus altissima, Acer pseudoplatanus, and Fraxinus excelsior for lead, cadmium, and zinc accumulation in contaminated soils of Zanjan Province, an industrial area with significant pollution. The evaluation employed a completely randomized design, with three treatment levels for each element, alongside a control treatment, replicated three times over a two-year period. A total of 810 one-year-old seedlings from the three species were involved in the study. Soil contamination levels, ranging from 0 to 2000 mg/kg for lead and zinc and from 0 to 200 mg/kg for cadmium, were administered through soil pot irrigation. Sampling of seedling stems and pot soils was conducted in November of 2021 and 2022. The absorption levels of elements in the samples were determined using the dry acid digestion method and an ICP-OES atomic absorption spectrometer. Results indicate species-specific variations in metal absorption, with Ailanthus showing the highest accumulation rates. Findings suggest Ailanthus as a promising candidate for soil improvement in polluted environments, particularly in contaminated soils of Zanjan Province. [ABSTRACT FROM AUTHOR]

Soil contamination and the uptake of pollutants by food crops are widespread issues that vary greatly by region and are influenced by the mineral composition of the soil and local human activities. The Pannonian region, where agriculture has played a key role since Roman times, has been particularly impacted by the long-standing agricultural and industrial practices. While soil contamination with heavy metals is monitored by the Slovenian government, microplastic contamination and the uptake of pollutants into food crops have yet to become a regular component of monitoring efforts. In this study, we conducted a preliminary investigation into soil and crop contamination across the Pannonian region, focusing on identifying harmful contaminants and their potential uptake into food crops. Both soil and crop samples were analyzed for the presence of heavy metals with proven methods such as atomic absorption spectrometry (FASS), graphite furnace atomic absorption spectrometry (GF-AAS), atomic fluorescence spectrometry (AFS), and inductively coupled plasma–mass spectrometry (ICP-MS). Energy-dispersive X-ray spectroscopy (EDS) was found to be a potentially faster method of obtaining data on soil composition. Special attention was also given to the potential presence of microplastics in the region's soils. [ABSTRACT FROM AUTHOR]

This study investigates the prevalence, distribution, and ecological consequences of 21 heavy metals (Ag, Al, As, B, Ba, Ca, Cd, Co, Cr, Cu, Fe, Hg, K, Li, Mg, Mn, Na, Ni, Pb, Sr, and Zn) in the soils between the Mahi and Dhadhar rivers in Gujarat, India. It aims to assess the seasonal variations in soil contamination and the potential human health risk associated with the heavy metal exposure through ingestion, inhalation, and dermal contact pathways. Soil samples were collected from 57 sites across three distinct seasons and analyzed using indices such as the geo-accumulation index, contamination factor, pollution load index, ecological risk factor, and global potential ecological risk. Human health risks were also evaluated for carcinogenic and non-carcinogenic effects. The findings reveal significant soil contamination, especially during the Monsoon and Post-Monsoon seasons, with heavy metals like Ag, Cd, Cr, Cu, Co, Ni, and Pb posing considerable ecological threats. Cr and Ni were identified as presenting the highest carcinogenic risks, while Fe and Cr posed major non-carcinogenic challenges. Seasonal variations significantly influenced heavy metal concentrations and distribution patterns. The study highlights the urgent need for comprehensive policies and sustainable practices to mitigate soil contamination and protect environmental health. It emphasizes the critical role of human activities, such as industrial, agricultural, and mining operations, in soil degradation and calls for increased community awareness and action to address these challenges. [ABSTRACT FROM AUTHOR]

The concentrations of toxic metals (TM) were analyzed in 498 samples of agricultural soils used for intensive vegetable cultivation in the watershed of Barracão dos Mendes, Brazil. The goal of this study was to characterize the distribution of these elements and the main natural and anthropogenic factors affecting their accumulation. In general, the average concentrations of TM were higher than the reference quality values for cultivated soils in the region, with the exception of Cr, Co, Ni and Mn, and the average concentration of Cd was ten times greater. Three sources of variation in the distribution of TM concentrations were identified: one related to topographic relief, another related to lithology, and one related to the massive use of agrochemicals. These factors contributed to TM accumulation in the soil; moreover, the transport of toxic metal-enriched clay by runoff resulted in higher concentrations of these elements in the lower parts of the slope. The long-term application of massive amounts of fertilizers and pesticides resulted in the accumulation of Cr, Cu, Zn, Ni, Pb and Cd in the vegetable cultivation soils and promoted the enrichment of macronutrients, mainly P and K. Moreover, the spatial distribution of TM in the agricultural soils of this mountain agroecosystem was affected by intensive vegetable cultivation, which altered the natural TM distribution dynamics determined by variations in topographic relief and lithology. In intensive cultivation areas, the TM distribution was also influenced by soil management practices such as tillage along the slope direction and massive mineral and organic fertilization. [ABSTRACT FROM AUTHOR]

Soil contamination, particularly by chromium from industrial effluents, remains a significant global environmental concern. Contaminant removal stands out as a pressing requirement in the current environmental landscape. The increased levels of these contaminants underscore the urgency for effective removal measures. This study focuses on the electrokinetic remediation of chromium-contaminated soil collected from Puliyantangal Lake, Ranipet, Tamil Nadu. Investigating the effects of supply voltage and bone dust amendment on chromium removal efficiency, the research sheds light on the details of this emerging in situ remediation technique. The results indicate that the optimal removal efficiency of hexavalent chromium [Cr(VI)] was achieved at 15 V with a maximum removal of 66.97%. Increased voltage enhanced Cr(VI) remediation through electromigration, while the dissociation of bone dust constituent (hydroxyapatite) positively impacted the removal process through chromium (III) hydroxide [Cr(OH)3] deposition and elevated Cr(VI) reduction. Furthermore, the study reveals a synergistic reduction in total chromium content through electromigration and chemical reduction of chromium species under direct current source application. The decreasing trend of Cr(VI) content from cathode to anode was observed for both 15 and 30 V, with enhanced reduction at higher voltages. Interestingly, the combination of bone dust amendment showed superior Cr(VI) removal efficiency at 15 V, emphasizing the significance of the relationship between voltage and amendment effectiveness. This unique interaction between hindered electromigration and enhanced Cr(VI) reduction holds promise for optimizing electrokinetic remediation strategies, providing valuable insights for future environmental remediation studies. [ABSTRACT FROM AUTHOR]

We developed a tailored statistical methodology to compare the contamination by chemical elements in soil of Arica, Chile in 2013 and 2014. We study the differences in the consecutive years 2013 and 2014 between arsenic, mercury, chromium, lead, and cadmium occurrence. The complicated aspect of such comparisons is that the heavy-tailed part of the distribution is mixing with the light-tailed distribution of the measurements and annual distributions of each element differ in their variances. We developed a novel sampling methodology based on the generalized Hill approach, which separates extreme values and the central part of the data. We perform a sensitivity analysis of the Fisher-Behrens test and investigate the effect of violation of homoscedasticity depending on the distributions of random samples. Those methods are useful for experimenters when testing for equality of means in sets with homoscedasticity. [ABSTRACT FROM AUTHOR]

Rice is a major dietary source of the toxic metal cadmium (Cd). Concentration of Cd in rice grain varies widely at the regional scale, and it is challenging to predict grain Cd concentration using soil properties. The lack of reliable predictive models hampers management of contaminated soils. Here, we conducted a three-year survey of 601 pairs of soil and rice samples at a regional scale. Approximately 78.3% of the soil samples exceeded the soil screening values for Cd in China, and 53.9% of rice grain samples exceeded the Chinese maximum permissible limit for Cd. Predictive models were developed using multiple linear regression and machine learning methods. The correlations between rice grain Cd and soil total Cd concentrations were poor (R² < 0.17). Both linear regression and machine learning methods identified four key factors that significantly affect grain Cd concentrations, including Fe-Mn oxide bound Cd, soil pH, field soil moisture content, and the concentration of soil reducible Mn. The machine learning-based support vector machine model showed the best performance (R² = 0.87) in predicting grain Cd concentrations at a regional scale, followed by machine learning-based random forest model (R² = 0.67), and back propagation neural network model (R² = 0.64). Scenario simulations revealed that liming soil to a target pH of 6.5 could be one of the most cost-effective approaches to reduce the exceedance of Cd in rice grain. Taken together, these results show that machine learning methods can be used to predict Cd concentration in rice grain reliably at a regional scale and to support soil management and safe rice production. [ABSTRACT FROM AUTHOR]

This study assessed the impact of phytoremediation on reducing the residual concentration of metolachlor in soil treated with doses of 530.7 and 1061.4 g/ha and its effect on microbial biodiversity in contaminated areas. For the plant species Avena sativa and Medicago sativa, a significant efficacy of 54.5 and 36.4% was observed in the dissipation of the herbicide, especially at higher doses. Although metolachlor application reduced soil microbial biodiversity, phytoremediating plants, especially M. sativa, promoted greater richness and distribution of microbial species, mitigating the negative effects of the herbicide. Principal component analysis revealed the influence of these plants and metolachlor on the composition of the microbial community. These results highlight the importance of phytoremediation in promoting soil biodiversity and reducing herbicide contamination, providing crucial insights for remediation strategies in contaminated areas. [ABSTRACT FROM AUTHOR]

Contamination of soil threatens the environment and can have a negative effect on soil strength parameters. Soil stabilization is one way to address this issue. In the present study, metakaolin geopolymer was used to stabilize contaminated clay. Initially, the effects of the concentration on the soil parameters was investigated. A combination of lead nitrate and zinc nitrate at a 1:1 ratio was used to contaminate the soil by introducing 1000, 5000 and 10,000 ppm of contaminants. The samples were subjected to a 7-day curing period after which the Atterberg limits, compaction, unconfined compressive strength (UCS), California bearing ratio (CBR) and pH tests were conducted. The results showed that the addition of 10,000 ppm of contaminant to the base soil decreased the CBR, UCS and pH by 21.07%, 23.37% and 15.51%, respectively. The most critical contaminant concentration was found to be 10,000 ppm. Next, soil samples contaminated with 10,000 ppm of lead and zinc nitrates was stabilized with 5%, 10% and 15% metakaolin geopolymer at curing times of 7, 14 and 28 days. After stabilization, the tests initially conducted on the contaminated samples without stabilizer were performed on samples stabilized with metakaolin geopolymer. The outcomes revealed that the soil strength parameters increased significantly with increases in the metakaolin geopolymer content and curing time. An increase in the curing time was shown to increase the UCS. The findings demonstrated that, after 28 days of curing, the soil pH of the stabilized samples with 5%, 10% and 15% metakaolin geopolymer increased by approximately 43.4%, 49.2% and 50.65%, respectively, in comparison with the soil containing 10,000 ppm of contaminants without stabilizer. [ABSTRACT FROM AUTHOR]

This detailed study assessed heavy metal contamination of sediments/soil near central India's largest copper mining area using 38 sampling sites within 10 km of the mine using atomic absorption spectroscopy. This study utilized multivariate pattern recognition methods, namely hierarchical clustering analysis (HCA) and principal component analysis (PCA), for source identification. Twelve parameters, i.e., copper (Cu), manganese (Mn), cobalt (Co), zinc (Zn), nickel (Ni), lead (Pb), organic matter (OM), cation exchange capacity (CEC), soil pH, distance (D), and elevation (E) were analyzed. The hierarchical cluster analysis (HCA) was used to analyze the sample sites with similar metal contamination and principal component analysis (PCA) was used to analyze the relationship between the parameters as well as to identify sources of heavy metal pollution. Three major pollution hotspots were detected by AHC and were classified as unpolluted/low pollution sites (UPS: mean concentration factor of 1.35 for Cu), highly polluted sites (HPS: mean concentration factor of 22 for Cu), and extremely polluted sites (EPS: mean concentration factor of 74 for Cu). PCA revealed three hidden factors/components, namely PC1 (explaining 38% of the variability), PC2 (18% of the variability), and PC3 (14% of the variability). Metals showed strong positive loading in PC1, explaining the highest variability. The mean content of Cu in soil/sediment samples was 502.526 mg/kg. The mean copper content was 10 times higher than the natural crustal value of 45mg/kg, indicating severe pollution in several sites around the study area. Mapping of copper contamination was conducted to reveal the spatial distribution of copper contamination using QGIS. This study exposes the heavy metal contamination level in surface sediments/soil and the effectiveness of pattern recognition techniques for the assessment of multivariate datasets in discerning spatial disparities and identifying the contamination causes. [ABSTRACT FROM AUTHOR]

Purpose: Manganese (Mn) is crucial in low concentrations but can become toxic in soils and sediments, affecting plants and animals. Understanding how plants inoculated with arbuscular mycorrhizal fungi (AMF) tolerate Mn is crucial for the application of these microorganisms in the remediation of contaminated soils. Despite recognized benefits in various plant species, assessing plant-AMF interaction effectiveness in mitigating Mn toxicity is crucial for undocumented plants. Methods: Acacia mangium Willd. plants were inoculated with an AMF native to a Mn mining area and grown in soil with increasing Mn levels (0, 200, and 400 mg kg−1) to evaluate the effects of inoculation on plant growth and plant-AMF association strategies to reduce Mn toxicity. Results: Inoculation with AMF resulted in beneficial effects, minimizing Mn toxicity and enhancing plant growth, despite reduced mycorrhizal colonization and AMF spore levels in the soil. Non-inoculated plants exposed to 400 mg kg−1 of Mn exhibited significant reductions in shoot dry mass (64.9%), number of leaves (25%), and root length (24%) compared to AMF-inoculated plants. Mn concentration was higher in the roots of AMF-inoculated plants at all Mn levels, indicating a restriction in Mn transport to the shoot, thus minimizing damage and promoting plant growth. Energy-dispersive spectroscopy identified Mn, potassium, phosphorus, iron and calcium in AMF spores, suggesting their protective role against Mn phytotoxicity and adaptability of this species of microorganism under stress conditions. Conclusion: The native AMF inoculation reduces toxicity and improves the growth of A. mangium Willd. under high levels of Mn in the soil. [ABSTRACT FROM AUTHOR]

Studies on tollbooth workers involving the concentration of metal(loid)s in highway dust are scarce. We aimed to assess the levels of metal(loid)s in soils and washed and unwashed leaves of Brachiaria decumbens on roadsides. Dust deposition and heavy metal content in the leaves are used to estimate the exposure of tollbooth workers to oral, inhalation, and dermal ingestion of metals in highway dust. The concentrations of aluminum (Al), arsenic (As), cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), iron (Fe), nickel (Ni), zinc (Zn), and lead (Pb) in washed and unwashed soil and leaves were analyzed using inductively coupled plasma optical emission spectroscopy. The results showed that soils along highways had a high concentration of heavy metals. Concentrations of Cd, Cu, Cr, Ni, and Pb near the roundabout and tollbooth are higher than the concentrations at the points between them. The highest transfer factor values were determined for aluminum. In the case of the non-carcinogenic effect, the hazard index (HI < 1) of tollbooth workers due to oral exposure to street dust containing metal(loid)s is higher than dermal contact and inhalation. The Incremental Lifetime Cancer Risk showed a high potential carcinogenic risk for As and Cd. [ABSTRACT FROM AUTHOR]

Soil contamination by heavy metals (HM) from pesticides poses a serious environmental threat, affecting sustainability and agricultural productivity. Soil enzymes are essential for biochemical reactions such as organic matter decomposition and nutrient cycling and are vital for maintaining soil health. However, the effects of HM on soil enzyme activity are not yet well understood. This study examined the impact of HM contamination on enzymatic stoichiometry in regions with intensive pesticide use. We selected flower cultivation areas with 5 years (CA1) and 10 years (CA2) of pesticide exposure and a native forest area (NFA) as a reference during the dry and rainy seasons. We measured Cd, Cu, Mn, Pb, and Zn levels and employed ecological risk indices to assess contamination levels. We also analyzed enzyme activities (arylsulfatase, β-glucosidase, acid phosphatase, urease) and enzymatic stoichiometry. CA2 exhibited the highest concentrations of Cd, Cu, and Mn in both periods, while Zn was highest in both CA1 and CA2. CA2 had higher values for all indices, indicating significant contamination. Compared with NFA, arylsulfatase activity was lower in cultivated areas during both periods, suggesting decreased soil quality. We found negative correlations between Cu, Mn, Zn, and arylsulfatase, as well as a reduction in urease with Cd; these elements also increased microbial C limitation. Our findings show that continuous pesticide input increases HM levels and that enzyme activity and stoichiometry are effective bioindicator of soil contamination. This study underscores the urgent need for guidelines to protect soils from prolonged HM buildup. [ABSTRACT FROM AUTHOR]

The Khanty-Mansi Autonomous Okrug-Yugra, situated within Russia's Far North, has undergone substantial industrialization and economic development. However, it is confronted with considerable environmental challenges, notably soil contamination. This study examines the presence of heavy metals (lead, cadmium, copper and zinc) in medicinal and berry plants from the forest ecosystem of this region. The following plant species were analyzed: Hypericum perforatum, Rubus arcticus, Origanum vulgare and Thymus vulgaris. The samples were taken from both open ground and hydroponic cultivation under artificial lighting. The findings indicate that the levels of lead present in all samples remain below the permissible limit of 10 mg/kg. Cadmium levels exhibited variability, with hydroponically grown plants containing 0.01 to 0.5 mg/kg and open ground Hypericum and Rubus perforatum containing up to 0.8 mg/kg. The combination of hydroponic cultivation and specific lighting conditions has been demonstrated to reduce lead and cadmium accumulation by a minimum of 1.6 times in comparison to open ground cultivation. The copper content of the samples ranged from 3 to 8 mg/kg, while the zinc content was 1.2–1.5 times higher in the plants grown in the open compared to those grown hydroponically. Notwithstanding these variations, the heavy metal content of all plant samples remains below the threshold values, thus rendering them safe for harvesting and utilization. This research serves to illustrate the environmental impact of industrial activities and to identify hydroponics as a potential strategy for their mitigation. [ABSTRACT FROM AUTHOR]

The occurrence of sand and dust storms (SDS) in Iran has raised many concerns about the possibility of environmental and public health hazards caused by dust particles and pollutants existed in these particles. Therefore, the purpose of this study was to investigate the possibility of contamination of surface soil, river sediments, and roadside deposits with radioactive materials, especially depleted uranium (DU) in the areas affected by SDS. The radioactive activity of the samples was measured by gamma spectroscopy with a high-purity germanium detector. The average activity concentrations of 226Ra, 232Th, and 40 K were 11.19, 8.05, and 76.05 Bq/kg. The average ratio of 238U/235U was 89 indicating the possibility of the presence of DU in the soil samples. The average values of Rm (the share of 235U in total uranium) and DUm were 0.55% (lower than natural uranium, 0.72) and 33% (indicating the presence of 33% DU on average in the samples). Based on 238U/226Ra activity, two samples (S11 and S12) should be considered as DU-contaminated. Almost the obtained results for all radiological risk indices showed lower values than the world average and the possibility of creating a low risk for working people, residents, visitors, and travelers passing through these areas. [ABSTRACT FROM AUTHOR]

This paper assesses the mass concentration of heavy metals in the soils of abandoned mines in the Chervonohrad mining district. The main negative factors of coal mining dumps include high acidity, exceeding the maximum permissible concentration of heavy metals, low organic matter content, low humidity, high temperature of substrates, wind and water erosion, steepness and large area of slopes. Heavy metals not only accumulate in the soils of the industrial zone, but also leak into the underground water. Soils in this area are heavily polluted, with the highest levels of contamination occurring at the foot of the dumps. The highest mass concentrations of aluminum and iron were found to exceed 1 mg/kg, indicating oversaturation with these metals. High concentrations of heavy metals can lead to changes in soil biological communities, impacting soil fertility. An analysis of cadmium levels near the coal mine dump showed a higher content of 0.62 mg/kg compared to the background area but did not exceed the maximum permissible concentration (MPC) of 0.7 mg/kg. The average metal content did not exceed 0.35 mg/kg. Cobalt levels in the study area ranged from 0.2 to 2.2 mg/kg, below the background level of 3.0 mg/kg and the MPC of 5 mg/kg. The waste from the coal industry exhibited a low content of mobile zinc, with a maximum concentration of 5.84 mg/kg, which is 0.15 MPC but exceeds the background concentration by more than 30%.

This study aims to assess the extent of hydrocarbon and heavy metal contamination in soils from specific areas on Azerbaijan's Absheron Peninsula, including Absheron, Suraxanı, and Baku, and to evaluate the impact of this contamination on soil properties. Soil samples were analyzed for Total Petroleum Hydrocarbons (TPH) and heavy metals, including aluminum, arsenic, cadmium, lead, and iron, alongside assessments of soil physical, chemical and biological properties. The results revealed significant contamination across all studied areas, particularly in Suraxanı, where TPH levels reached 190 ± 20 mg/kg, exceeding the environmental standard of 100 mg/kg. Similarly, Suraxanı soils exhibited alarmingly high concentrations of heavy metals, with aluminum at 30,128 ± 1,500 mg/kg, arsenic at 50.94 ± 2.5 mg/kg, and cadmium at 0.153 ± 0.01 mg/kg, all surpassing acceptable limits. These contaminants severely degraded soil health, evidenced by increased bulk density (1.7 g/cm³ in Suraxanı) and reduced soil porosity. Microbial activity, a key indicator of soil fertility, was also markedly lower in contaminated regions, with the total bacterial count in Suraxanı being less than half that of the uncontaminated area. The findings underscore the urgent need for comprehensive soil management practices and stricter environmental regulations to mitigate contamination's adverse effects and protect both ecosystems and public health in Azerbaijan’s petroleum contaminated areas.

In this study, we first produced the Korean-specific dose coefficients (DCs) for soil contamination using the Mesh-type Reference Korean Phantoms (MRKPs). The Korean DCs were compared with the values in ICRP Publication 144 produced using the Caucasian-based ICRP reference phantoms to investigate dosimetric impact due to the racial difference (Korean/Asian vs Caucasian). Monte Carlo dose calculations using the Geant4 code were conducted where the photon and electron sources in the phase-space data used for the ICRP-144 DC calculations were irradiated to the MRKPs. For photons, the organ DCs of the MRKPs showed a good agreement with the ICRP-144 DCs (deviations 20 % for most cases). The effective DCs of the MRKPs showed an excellent agreement with the ICRP-144 DCs for photons (deviations

The precise range of contamination determines the cost of treating heavy metals contamination of soils at industrial sites and was a key aspect of soil heavy metals contamination management. The pollution level and spatial correlation of As, Cd, Cr, Cu, Hg, Ni, Pb and Zn in one hundred and thirty topsoil samples from a typical contaminated site was analysed. Geochemical analysis showed that Hg pollution was the most serious in the site, followed by Cd, Pb, Zn, Cu and Cr. The contents of As and Ni in the soil did not exceed the background values. The interpolation accuracy, interpolation results and spatial distribution of inverse distance weight method (IDW), local polynomial method (LPI), radial basis function method (RBF) and ordinary kriging method (OK) were compared, respectively. The results show that the range, mean and coefficient of variation of the four interpolation methods were generally lower than that of the sampled data, which was mainly caused by smoothing effect. The smoothing effect of LPI and OK were the most serious, while the smoothing effect of IDW and RBF were not obvious. The optimal interpolation method of Cd, Cr, Hg, Pb and Zn in polluted sites was RBF and the optimal interpolation method for As, Cu and Ni was IDW. The evaluation of polluted area by IDW and RBF interpolation method was ranked as IDW > RBF, which was much larger than that calculated by sampling point. Both interpolation methods could increased the area of polluted area. The probability kriging (PK) method was similar to that based on sampling points, which can greatly improve the calculation accuracy of heavy metals polluted area in industrial contaminated sites. Geochemical data and spatial interpolation results show that phytoremediation techniques was the most suitable for remediation of heavy metal contaminated soils at this site. [ABSTRACT FROM AUTHOR]

This paper assesses the mass concentration of heavy metals in the soils of abandoned mines in the Chervonohrad mining district. The main negative factors of coal mining dumps include high acidity, exceeding the maximum permissible concentration of heavy metals, low organic matter content, low humidity, high temperature of substrates, wind and water erosion, steepness and large area of slopes. Heavy metals not only accumulate in the soils of the industrial zone, but also leak into the underground water. Soils in this area are heavily polluted, with the highest levels of contamination occurring at the foot of the dumps. The highest mass concentrations of aluminum and iron were found to exceed 1 mg/kg, indicating oversaturation with these metals. High concentrations of heavy metals can lead to changes in soil biological communities, impacting soil fertility. An analysis of cadmium levels near the coal mine dump showed a higher content of 0.62 mg/kg compared to the background area but did not exceed the maximum permissible concentration (MPC) of 0.7 mg/kg. The average metal content did not exceed 0.35 mg/kg. Cobalt levels in the study area ranged from 0.2 to 2.2 mg/kg, below the background level of 3.0 mg/kg and the MPC of 5 mg/kg. The waste from the coal industry exhibited a low content of mobile zinc, with a maximum concentration of 5.84 mg/kg, which is 0.15 MPC but exceeds the background concentration by more than 30%. [ABSTRACT FROM AUTHOR]

Arbuscular mycorrhizal fungi are highly important in improving plant growth and decreasing the negative effects of contaminants. The objective of this study was to evaluate the effect of inoculation of mycorrhizal fungus on the concentration of lead (Pb) and cadmium (Cd) by parsley (Petroselinum sativum) in heavy metal-contaminated soil in the presence of kerosene. This study was carried out as a factorial experiment based on the randomized complete design with four replications under greenhouse conditions. Experimental factors were included: 1- microbial inoculation in two levels with mycorrhizal fungus (Rhizophagus irregularis) and control (without inoculation), and 2- kerosene in four levels of 0, 4, 8, and 12 mL kg-1 soil. The results showed that mycorrhizal inoculation led to a significant increase in root (61.1 to 150.1%) and shoot dry weight (9.1 to 51.5%), shoot P, Zn, and Cu concentration and root Pb (18.7 to 97.9%) and Cd (13.3 to 98.6%) concentration, while significantly decreased shoot Pb (10.0 to 29.2%) and Cd (19.6 to 72.1%) concentration. The root bio-concentration factor (BCF) (7.74%) was higher than compared to shoot BCF. The mycorrhizal inoculation decreased the translocation factor (TF) of Pb and Cd. The TF

Abstract Background Soil contamination by heavy metals is a critical environmental challenge, with Pb being of particular concern due to its propensity to be readily absorbed and accumulated by plants, despite its lack of essential biological functions or beneficial roles in cellular metabolism. Within the scope of phytoremediation, the use of plants for the decontamination of various environmental matrices, the present study investigated the potential of activated charcoal (AC) to enhance the tolerance and mitigation capacity of S. sesban seedlings when exposed to Pb. The experiment was conducted as a factorial arrangement in a completely randomized design in hydroponic conditions. The S. sesban seedlings were subjected to a gradient of Pb concentrations (0, 0.02, 0.2, 2, and 10 mg/L) within the nutrient solution, alongside two distinct AC treatments (0 and 1% inclusion in the culture media). The study reached its conclusion after 60 days. Results The seedlings exposed to Pb without AC supplementation indicated an escalation in peroxidase (POX) activity, reactive oxygen species (ROS), and malondialdehyde (MDA) levels, signaling an increase in oxidative stress. Conversely, the incorporation of AC into the treatment regime markedly bolstered the antioxidative defense system, as evidenced by the significant elevation in antioxidant capacity and a concomitant reduction in the biomarkers of oxidative stress (POX, ROS, and MDA). Conclusions With AC application, a notable improvement was observed in the chlorophyll a, total chlorophyll, and plant fresh and dry biomass. These findings illuminate the role of activated charcoal as a viable adjunct in phytoremediation strategies aimed at ameliorating heavy metal stress in plants.

Abstract In this study, various constraints of Cd toxicity on growth, morpho-anatomical characters along with physiological and biochemical metabolic processes of Solanum melongena L. plants were analyzed. Conversely, ameliorative role of iron oxide nanoparticles (FeONPs) was examined against Cd stress. For this purpose, the following treatments were applied in completely randomized fashion; 3 mM CdCl2 solution applied with irrigation water, 40 and 80 ppm solutions of FeONPs applied via foliar spray. Regarding the results, Cd caused oxidative damage to plants’ photosynthetic machinery, resulting in elevated levels of stress-markers like malondialdehyde (MDA), hydrogen peroxide (H2O2), and electrolytic leakage (EL) along with slight increase in antioxidants activities, including glutathione (GsH), ascorbate (AsA), catalases (CAT), peroxidases (POD), superoxide dismutase (SOD), and ascorbate peroxidases (APX). Also, high Cd level in plants disturb ions homeostasis and reduced essential minerals uptake, including Ca and K. This ultimately reduced growth and development of S. melongena plants. In contrast, FeONPs supplementations improved antioxidants (enzymatic and non-enzymatic) defenses which in turn limited ROS generation and lowered the oxidative damage to photosynthetic machinery. Furthermore, it maintained ionic balance resulting in enhanced uptake of Ca and K nutrients which are necessary for photosynthesis, hence also improved photosynthesis rate of S. melongena plants. Overall, FeONPs foliar spray effectively mitigated Cd toxicity imposed on S. melongena plants.

This study assessed the impact of phytoremediation on reducing the residual concentration of metolachlor in soil treated with doses of 530.7 and 1061.4 g/ha and its effect on microbial biodiversity in contaminated areas. For the plant species Avena sativa and Medicago sativa, a significant efficacy of 54.5 and 36.4% was observed in the dissipation of the herbicide, especially at higher doses. Although metolachlor application reduced soil microbial biodiversity, phytoremediating plants, especially M. sativa, promoted greater richness and distribution of microbial species, mitigating the negative effects of the herbicide. Principal component analysis revealed the influence of these plants and metolachlor on the composition of the microbial community. These results highlight the importance of phytoremediation in promoting soil biodiversity and reducing herbicide contamination, providing crucial insights for remediation strategies in contaminated areas.

Abstract Background The potential of phytoremediation using garlic monoculture (MC) and intercropping (IC) system with perennial ryegrass to enhance the uptake of cadmium (Cd), chromium (Cr), and lead (Pb) were investigated. Results Positive correlations were found between MC and IC systems, with varying biomass. Production of perennial ryegrass was affected differently depending on the type of toxic metal present in the soil. Root growth inhibition was more affected than shoot growth inhibition. The total biomass of shoot and root in IC was higher than MC, increasing approximately 3.7 and 2.9 fold compared to MC, attributed to advantages in root IC crop systems. Photosystem II efficiency showed less sensitivity to metal toxicity compared to the control, with a decrease between 10.07–12.03%. Among gas exchange parameters, only Cr significantly affected physiological responses by reducing transpiration by 69.24%, likely due to leaf chlorosis and necrosis. Conclusion This study exhibited the potential of garlic MC and IC with perennial ryegrass in phytoremediation. Although the different metals affect plant growth differently, IC showed advantages over MC in term biomass production.

Accumulated copper (Cu) in agricultural soils is non-biodegradable and persists in the environment, which imposes the need for its regular monitoring by selective, rapid, simple, and low-cost analytical techniques. The performance of portable X-ray fluorescence spectrometers (pXRF) has significantly improved in the last ten years, and they are increasingly applied for environmental, agronomic, and soil science purposes. This study aims to compare the total Cu content determined in agricultural soil samples using three analytical methods (inductively coupled plasma mass spectrometry, (ICP-MS), atomic absorption spectrophotometry (AAS), and pXRF). The research was based on analyses of thirty-five soil samples collected from two vineyards, arable land, and a meadow located in North-West Croatia. In air-dried, milled, and homogenized soil samples, Cu content was detected using a hand-held XRF analyzer under laboratory conditions, while ICP-MS and AAS analysis were performed after open digestion by aqua-regia. Determined Cu content varied in very similar ranges from 51.2 mg/kg to 444.3 mg/kg with an average of 138.9 mg/kg for AAS; from 48.6 mg/kg to 446.4 mg/kg and an average of 139.7 mg/kg for ICP-MS and from 54.0 mg/kg to 435.3 mg/kg with an average of 141.3 mg/kg for pXRF. A high positive correlation between Cu content determined by pXRF and ICP-MS (R2 = 0.996), as well as between pXRF and AAS (R2 = 0.997), along with the results of Bland-Altman statistical analysis indicate that pXRF can be applied as a reliable tool for analyses of Cu-contaminated agricultural soil.

Abstract Sewage sludge (SS) application to forest plantation soils as a fertilizer and/or soil amendment is increasingly adopted in plantation forest management. However, the potential risks of SS-derived heavy metals (HMs) remain a concern. Many factors, including woodland slope may affect the risks, but the understanding of this issue is limited. This research evaluated the HMs migration via surface runoff, interflow, and sediments when SS was applied in woodlands of varying slopes. We conducted indoor rainfall simulations and natural rainfall experiments to clarify the effect of slope on the migration of HMs via runoff (including surface and interflow) and sediments. In the simulated rainfall experiment, HMs lost via sediments increased by 9.79–27.28% when the slope increased from 5° to 25°. However, in the natural rainfall experiment, when the slope of forested land increased from 7° to 23°, HMs lost via surface runoff increased by 2.38% to 6.13%. These results indciate that the surface runoff water on a high slope (25°) posed high water quality pollution risks. The migration of HMs via surface runoff water or interflow increased as the steepness of the slope increased. The total migration of Cu, Zn, Pb, Ni, Cr and Cd via sediment greatly exceeded that via surface runoff and interflow. Particles ≤ 0.05 mm contributed the most to the ecological risks posed by sediments. Cd was the main source of potential ecological risks in sediments under both experimental conditions.

Soil contamination due to urban and industrial activities has caused significant land degradation and changes in the geotechnical properties of soils. Among many contaminants, hydrocarbons pose severe threats not only from an engineering point of view but are also hazardous to the environment. This review article critically analyzes the essential aspects of different hydrocarbon types as a contamination source in various soil types and their implications in the geotechnical design. The modifications of geotechnical properties require an in-depth investigation, especially at the micro-scale, by assessing the soil particle interaction with hydrocarbons. The hydrocarbon compounds possess the ability to alter the morphological characteristics of soil particles, which, in turn, influences the shear mobilization in soils. Furthermore, several remediation techniques, such as biological, chemical, physical, or thermal treatment methods, are available to solidify, remove or immobilize hydrocarbons. However, limitations exist due to the applicability of some techniques. Taking these considerations into account, the primary purpose of this paper is to create a consensus about how hydrocarbons interact with different soils, what are the triggers of these interactions, which geotechnical properties are mostly affected, which remediation techniques will be more effective, and how quickly the method can be applied. [ABSTRACT FROM AUTHOR]

Introduction: Emerging contaminants in irrigation wastewater can cause bioaccumulation in crops, posing health risks to humans and other living organisms. The extent to which different emerging contaminants (ECs) are taken up by plants varies depending on the physicochemical properties of the contaminants and the type of crops grown. Methods: This study investigated the fate of emerging contaminants (ECs), particularly pharmaceuticals, in durum wheat grown on soils irrigated with treated wastewater in southern Italy. The experiment was conducted in lysimeters irrigated with wastewater during previous crop cycles, assessing the presence and distribution of ECs in both soil and plant tissues. Three different levels of exposure to ECs were compared: freshwater irrigation (FW), wastewater treated to European average contaminant levels (TWWx1), and a triple dose of contaminants (TWWx3). Results: The behavior of 12 different ECs in the plant-soil complex was analyzed and found variable. Fluconazole and carbamazepine were found to have higher uptake concentrations in the plant, with accumulation observed in the plant and grain, especially in the TWWx3 treatment. However, some ECs (such as Sulfamethoxazole, Trimethoprim, Ketoprofen, Diclofenac, Metoprolol, and Naproxen) showed high uncertainties in their fate, probably due to degradation in soil and influential crop parameters. Discussion: The results of this study contribute to the argument that the reuse of treated wastewater for irrigation, if properly monitored, can be a safe approach in agriculture and can support policymakers in developing future legislative frameworks for sustainable water management. [ABSTRACT FROM AUTHOR]

Soil and groundwater contamination has been raised as a concern due to the capability of posing a risk to human health and ecology, especially in facing highly toxic and emerging pollutants. Because of the prevalent usage of perfluorooctanoic acid (PFOA), in industrial and production processes, and subsequently the extent of sites contaminated with these pollutants, cleaning up PFOA polluted sites is paramount. This research provides a review of remediation approaches that have been used, and nine remediation techniques were reviewed under physical, chemical, and biological approaches categorization. As the pollutant specifications, environmental implications, and adverse ecological effects of remediation procedures should be considered in the analysis and evaluation of remediation approaches, unlike previous research that considered a couple of PFAS pollutants and generally dealt with technical issues, in this study, the benefits, drawbacks, and possible environmental and ecological adverse effects of PFOA-contaminated site remediation also were discussed. In the end, in addition to providing sufficient and applicable understanding by comprehensively considering all aspects and field-scale challenges and obstacles, knowledge gaps have been found and discussed. [ABSTRACT FROM AUTHOR]

Background: Soil contamination by heavy metals is a critical environmental challenge, with Pb being of particular concern due to its propensity to be readily absorbed and accumulated by plants, despite its lack of essential biological functions or beneficial roles in cellular metabolism. Within the scope of phytoremediation, the use of plants for the decontamination of various environmental matrices, the present study investigated the potential of activated charcoal (AC) to enhance the tolerance and mitigation capacity of S. sesban seedlings when exposed to Pb. The experiment was conducted as a factorial arrangement in a completely randomized design in hydroponic conditions. The S. sesban seedlings were subjected to a gradient of Pb concentrations (0, 0.02, 0.2, 2, and 10 mg/L) within the nutrient solution, alongside two distinct AC treatments (0 and 1% inclusion in the culture media). The study reached its conclusion after 60 days. Results: The seedlings exposed to Pb without AC supplementation indicated an escalation in peroxidase (POX) activity, reactive oxygen species (ROS), and malondialdehyde (MDA) levels, signaling an increase in oxidative stress. Conversely, the incorporation of AC into the treatment regime markedly bolstered the antioxidative defense system, as evidenced by the significant elevation in antioxidant capacity and a concomitant reduction in the biomarkers of oxidative stress (POX, ROS, and MDA). Conclusions: With AC application, a notable improvement was observed in the chlorophyll a, total chlorophyll, and plant fresh and dry biomass. These findings illuminate the role of activated charcoal as a viable adjunct in phytoremediation strategies aimed at ameliorating heavy metal stress in plants. [ABSTRACT FROM AUTHOR]

In the oil and gas sector of Basrah, natural radioactive materials are accumulated in various equipment like wellheads, pumps, and separation vessels, often manifested as scales, sludge, and other forms of waste. Without proper preventive measures, these accumulations pose significant risks to workers, the public, and the environment. This study aims to assess the lifelong cancer risks associated with production processes and the handling of resultant waste, be it scale sediments, sludge, or soil. Sample collection across different regions was based on the evaluation of production and storage facilities. Using a high-purity germanium detector (HPGe), activity concentrations of 226Ra, 232Th, and 40K were measured. These concentrations were then used with standard equations to determine indoor effective dose rates. The regional-weighted (the lifetime risk of cancer is a measure of the cumulative risk of cancer over a specific age range and has a clear, intuitive appear) average of the lifetime excessive cancer risk was varied between (0.40 to 0.11 ×10-3) for ELCRoutdoor, (3.13 to 0.86 ×10-3) for ELCRindoor and (0.97 to 3 ×10-3) for ELCRtotal, significantly surpassing the global average value of (0.29x10-3). This disparity underscores the heightened risk posed by these activities, emphasizing the urgent need for enhanced safety measures and regulatory oversight to safeguard human health and the environment. [ABSTRACT FROM AUTHOR]

In this study, various constraints of Cd toxicity on growth, morpho-anatomical characters along with physiological and biochemical metabolic processes of Solanum melongena L. plants were analyzed. Conversely, ameliorative role of iron oxide nanoparticles (FeONPs) was examined against Cd stress. For this purpose, the following treatments were applied in completely randomized fashion; 3 mM CdCl2 solution applied with irrigation water, 40 and 80 ppm solutions of FeONPs applied via foliar spray. Regarding the results, Cd caused oxidative damage to plants' photosynthetic machinery, resulting in elevated levels of stress-markers like malondialdehyde (MDA), hydrogen peroxide (H2O2), and electrolytic leakage (EL) along with slight increase in antioxidants activities, including glutathione (GsH), ascorbate (AsA), catalases (CAT), peroxidases (POD), superoxide dismutase (SOD), and ascorbate peroxidases (APX). Also, high Cd level in plants disturb ions homeostasis and reduced essential minerals uptake, including Ca and K. This ultimately reduced growth and development of S. melongena plants. In contrast, FeONPs supplementations improved antioxidants (enzymatic and non-enzymatic) defenses which in turn limited ROS generation and lowered the oxidative damage to photosynthetic machinery. Furthermore, it maintained ionic balance resulting in enhanced uptake of Ca and K nutrients which are necessary for photosynthesis, hence also improved photosynthesis rate of S. melongena plants. Overall, FeONPs foliar spray effectively mitigated Cd toxicity imposed on S. melongena plants. [ABSTRACT FROM AUTHOR]

Anthropogenic activities predominantly affect environmental Pb pollution, especially during waste lead-acid battery (LAB) recycling operations. In this study, the presence of Pb and nine other potentially toxic elements (PTEs) in the soil at an abandoned LAB recycling site was investigated. The focus was on spatial and vertical distributions and potential health issues related to PTEs. Average concentrations of Cd, As, Hg, Pb, Al, Zn, Cu, and Sb were elevated at all investigated soil depths, whereas the concentrations of Zn, Cu, and Sb were significant only on the soil surface. Positive matrix factorization, correlation and cluster analyses, as well as self-organizing maps, identified four primary pollution sources: recycling activities (Cd, Hg, Pb, and Sb), mixed anthropogenic sources (Zn and Cu), the soil parent material (As, Cr, and Ni), and surface runoff combined with sand application (Al and pH). While the non-carcinogenic risk results revealed a negligible risk for adults, the hazard index (HI) values for children were greater than one in 26% of the samples. For adults and children, the total carcinogenic risk (TCR) values were acceptable for 98% and 94% of the samples, respectively. Geospatial analysis identified the main hotspot in the battery disposal area. Source-specific non-carcinogenic and carcinogenic risks were most influenced by recycling activities. Monte Carlo simulation (MCS) of total HI for children showed that the risk value exceeded the threshold level (HI > 1) at the 10th percentile, whereas the maximum value of total HI for adults was 0.2. Regarding carcinogenic risk, the TCR values at the 95th percentile of all four sources for adults and children were below the limit value (1 × 10−4), indicating a low probability of cancer development. [ABSTRACT FROM AUTHOR]

Concern over the harmful impacts of heavy metal pollution in soil has increased dramatically on a global scale. For the sake of environmental preservation, accurate estimates of the heavy metal concentrations in soil are essential. This study provides valuable data regarding heavy metal concentrations in soil collected from field crops production area in Central and Western Serbia. Five wider localities in the zones of Central and Western Serbia were selected for the collection of soil samples. Based on our research, focused on determining the total contents of heavy metals in the soil and the degree of pollution in the environment caused by their behavior, distribution, and origin, it can be concluded that there is pronounced variability in relation to localities. Heavy metal contents were mostly within the same ranges as those in similar soils from Europe and around the world. Any pollution control system must include heavy metal monitoring, including the methodical collection of data on the concentrations of heavy metals in a particular environment. Before environmental degradation occurs, it is crucial to set pollution limits and implement efficient monitoring procedures. [ABSTRACT FROM AUTHOR]

Gold mining is acknowledged as a principal source of environmental contamination, primarily due to the release of potentially toxic elements (PTEs) through tailings dispersion into adjacent soils. Such contamination leads to land degradation, pollution, biodiversity loss and soil contamination, and subsequently impacts the food chain, human health and soil ecosystems. This study evaluates the extent of PTE contamination in soils at artisanal and small-scale gold mining (ASGM) sites within the Meiganga area of the Adamawa-Yade Domain, Cameroon. ASGM extraction processes from quartz veins in this area involve the removal of topsoil to access the ore. Comparative analysis of soil samples from three profiles within the mining zone were conducted to determine contamination levels using pollution indices: enrichment factor, geoaccumulation index, contamination factor and pollution load index. Results indicate higher concentrations of PTEs in soils from the mining area compared to the control profile, with notable contamination in the bottom slope profiles and B horizons, reflecting considerable metal accumulation. The contamination levels of PTEs substantially exceed background levels in the upper continental crust. The study attributes the elevated concentrations of PTEs not only to local mineralization but also to anthropic activities, particularly ASGM, which contributes to their enrichment, distribution and mobility. This pronounced contamination necessitates immediate intervention, advocating for pollution-control measures to address potential ecosystem and human health risks. It highlights the environmental toll of ASGM and underscores the imperative for sustainable mining practices and effective soil remediation techniques, including phytoremediation and soil replacement, to alleviate the adverse effects. [ABSTRACT FROM AUTHOR]

In recent decades, the application of machine learning methods as a powerful tool supporting accurate and representative models has become common in various fields, including pollution assessment in soil and sediment. Widespread contamination in these areas, causing severe impacts on ecosystems and living beings, has resulted in the development of numerous models based on machine learning techniques. These models have been used to detect, trace, and predict the extent of contamination levels and create specified management plans. This paper provides a bibliometric analysis of the evaluation of soil and sediment contamination and treatment strategies using machine learning studies from 1986 to 2022. Meaningful analysis has been done on research trends, publishing activity of journals, most active countries, subject areas, top authors, and author keywords. The research showed that China with the highest number of publications has made extensive investments and has put a special focus on this area. The most studied contaminants are heavy metals, followed by polycyclic aromatic hydrocarbons, and persistent organic pollutants. The artificial neural network followed by cluster analysis and principal component analysis are the most widely used methods. [ABSTRACT FROM AUTHOR]

The soil, comprising minerals, organic matter, and living organisms, serves as a critical component of our environment. However, anthropogenic activities, such as uncontrolled sewage disposal and industrial waste, have led to pervasive soil pollution, impacting ecosystems and human health. This comprehensive study scrutinizes the intricate dynamics of soil pollution resulting from open waste dumping, specifically examining its impact on the health of local communities and the environment in Haridwar municipality. In this study, four solid waste dumping sites were meticulously surveyed, with soil samples analyzed for 19 parameters through statistical tools like one-way ANOVA, Kruskal–Wallis tests, soil pollution indices, and potential health risk assessment. The Geo-accumulation Index (Igeo) and contamination factor (CF) followed the heavy metals in the order of Zn > Mn > Fe > Cu in all selected sites. Additionally, a potential health risk assessment considered ingestion, inhalation, and dermal exposure pathways, revealing a high non-carcinogenic risk of metals (Mn > Fe > Zn > Cu) for both children and adults. In the ingestion pathway, the hazard quotient indicated a high risk of metals for both children and adults in the range of 1192.73 to 2066.94 for child and 191.98 to 312.16 for adults. Crucially, the HQ revealed potential health risks, emphasizing the urgency of addressing metal contamination. However, the findings indicate that dumping sites directly or indirectly affects the local people of Haridwar municipality. Therefore, this study provides a baseline framework for minimizing the impact of dumping sites on local population and the environment. [ABSTRACT FROM AUTHOR]