Contamination Of Agricultural Soils Research Articles

Insights into Agricultural Soil Contamination by a Veterinary Antibiotic TYLOSIN Through Continuous Run-Off Conditions

ABSTRACT 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.

Early warning of heavy metals contamination in agricultural soils: Spatio-temporal distribution and future trends in the Hexi Corridor

Conducting risk and early warning assessments of heavy metals (HMs) pollution in agricultural soils holds significant importance for pollution prevention and sustainable agricultural development. Early warning studies on heavy metal contamination of agricultural soils in oases in arid zones are rare in previous studies, therefore, this study carried out spatial and temporal simulation and early warning studies on the environmental capacity of agricultural soils in the Hexi Corridor based on field monitoring data and remote sensing technology and other methods. The results revealed that agricultural soils have been affected by human activities, leaving HMs at a moderate pollution level. The mean environmental capacity indices for Cr, Ni, Cu, Zn, As and Pb showed that they all belonged to the medium-capacity state, and 7.01 % of the sampling points being overloaded and in the low capacity for As. Cr, Ni, Zn and As were found in the moderate and high capacity zones located in the study area's western part, and the spatial distribution was basically the same. HMs in the middle parts area were dominated by low to medium capacity status, which may be related to agricultural activities such as application of fertilizers and pesticides and sewage irrigation. Based on the soil dynamic capacity model, it was found that in the next 20 years, HMs showed a decrease of 70–80 %, and the soil environment dynamic capacity was smaller than both the static and existing capacity, and it showed a decreasing trend with the change of time, which indicated that the soil's capacity for pollutants in the study area would be reduced if no pollution control measures were taken. Risk warning results showed that the overall spatial distribution pattern of the probability of pollution in the study area during the next 10 and 20 years was lower in the west and the northern part of Wuwei City, and higher in the middle part. This study suggests constructing a management system of “pollution evaluation - source treatment - risk early warning” for heavy metal contaminated sites, formulating corresponding policies and early warning measures, strengthening the research and development of monitoring, remediation, and treatment technologies, and realizing the prevention and control of agricultural soil pollution and sustainable development in the study area.

Herbicide contamination of Batak plain agricultural soils and risk assessment

Herbicide residue levels were analyzed in agricultural soils of Batak plain and health risk assessments were made for relevant pesticides. Herbicide contamination levels were analyzed with the use of Quick-Easy-Cheap-Efficient-Rugged-Safe (QuEChERS)-liquid chromatography/tandem mass spectrometry (LC–MS/MS) procedure. Herbicide-free soil samples were spiked at two different levels. Overall recovery of the method was 87.32%. Present findings were parallel to SANTE recovery limits. About 50% of collected samples from the study sites contained herbicides at different concentrations. Totally, eight herbicides were detected, and herbicide concentrations ranged between 1.085 and 1724.23 μg kg−1. Metolachlor had the highest concentration (1724.23 μg kg−1) in a sample taken close to the pesticide waste disposal area. Six herbicides were detected at different concentrations in the same sample. Persistent herbicides (terbuthylazine and pendimethalin) were detected in 35 samples. Risk assessments revealed that hazard index (HI) and hazard quotient (HQ) were less than 1. The greatest HQ values were identified for terbuthylazine as 2772.48 × 10−7 and 20793.61 × 10−7 for adults and children, respectively. The HI for all herbicides were 3916.05 × 10−7 for adult and 29370.39 × 10−7 for children.

Spatial distribution of heavy metal abundance at distance gradients of roadside agricultural soil from the busiest highway in Bangladesh: A multi-index integration approach

Bangladesh is currently experiencing significant infrastructural development in road networking system through the construction or reconstruction of multiple roads and highways. Consequently, there is a rise in traffic intensity on roads and highways, along with a significant contamination of adjacent agricultural soils with heavy metals. The purpose of this study was to evaluate the ecological risk, health risk and the abundance of seven heavy metals (Cu, Mn, Pb, Cd, Cr, As, and Ni) in three distance gradients (0, 300, and 500 m) of agricultural soil along the Dhaka-Chattogram highway. The concentration of heavy metals was measured with an Atomic Absorption Spectrophotometer (AAS) on a total of 36 soil samples that were taken from 12 different sampling sites. Based on the findings, Cd had a high contamination factor for all distance gradients, whereas Cr had a moderate contamination factor in 67% of the study areas. According to the Pollution Load Index (PLI), Cd, Cr, and Pb were the predominant pollutants. Principal component analysis (PCA) result shows these metals mainly came from anthropogenic sources. The considerable positive correlations between Cu–Pb, Cu–Cd, Pb–Cd, and Cr–Ni all pointed to shared anthropogenic origins. As per Potential Ecological Risk Assessment (PERI) analysis, Pb, Cd, Cr, and Ni each contribute significantly and pose a moderate threat. The Target Hazard Quotient (THQ) values for all pathways of exposure to Pb and Cr in soils were more than 1, which would pose a significant risk to human health in the following order: THQadult female > THQadult male > THQchildren. This study will help to evaluate the human health risk and develop a better understanding of the heavy metal abundance scenario in the agricultural fields adjacent to this highway.

Iron-modified biochar effectively mitigates arsenic-cadmium pollution in paddy fields: A meta-analysis

The escalating problem of compound arsenic (As) and cadmium (Cd) contamination in agricultural soils necessitates the urgency for effective remediation strategies. This is compounded by the opposing geochemical behaviors of As and Cd in soil, and the efficacy of biochar treatment remains unclear. This pioneering study integrated 3780 observation pairs referred from 92 peer-reviewed articles to investigate the impact of iron-modified biochar on As and Cd responses across diverse soil environments. Regarding the treatments, 1) biochar significantly decreased the exchangeable and acid-soluble fraction of As (AsF1, 20.9%) and Cd (CdF1, 24.0%) in paddy fields; 2) iron-modified biochar significantly decreased AsF1 (32.0%) and CdF1 (27.4%); 3) iron-modified biochar in paddy fields contributed to the morphological changes in As and Cd, mainly characterized by a decrease in AsF1 (36.5%) and CdF1 (36.3%) and an increase in the reducible fraction of As (19.7%) and Cd (39.2%); and 4) iron-modified biochar in paddy fields increased As (43.1%) and Cd (53.7%) concentrations in the iron plaque on root surfaces. We conclude that iron-modified biochar treatment of paddy fields is promising in remediating As and Cd contamination by promoting the formation of iron plaque.

Ecological risk assessment of potentially toxic elements (PTEs) in agricultural soil, vegetables and fruits with respect to distance gradient in proximity to lead-acid battery industry

Lead-acid battery industries in Bangladesh have proliferated in urban areas, leading to the release of significant amounts of potentially toxic elements (PTEs) and metalloids into the environment. This study aimed to assess the spatial distribution, sources, contamination status, and ecological risks in agricultural soils, vegetables, and fruits near these industries. Soil samples were collected from four sites at varying distances (0 m, 100 m, 250 m, and 500 m) around three lead-acid battery industries (AA, AB, and AC) in Dhaka and Gazipur Districts during June-July 2020. The concentrations of the Pb, As, Cd and Zn in agricultural soils were ranged between 8.40–116.61, 8.99–28.21, 0.03–1.28, and 25.38–68.72 mg/kg, respectively. The concentrations of Pb, As, and Cd were found to be considerably higher than background levels across all industries, with a gradual decrease in PTE concentrations from 0 m to 500 m. The contamination factor indicated high to moderate contamination in agricultural soils by As, Cd, and Pb, and low contamination by Zn. pollution load index, modified contamination degree, and nemerow comprehensive index revealed varying pollution levels in the vicinity of the industries, with AA and AB showing higher pollution compared to AC. The individual risk factors demonstrated significant risks associated with Cd and As exposure, while Pb and Zn posed lower risks. The potential ecological risk index indicated considerable ecological risk for AA (risk index = 192.41), moderate risk for AB (risk index = 111.80), AC (risk index = 65.08), respectively. Correlation and principal component analysis revealed strong positive associations (p < 0.01) among the chemical parameters and potentially toxic elements in soils, and demonstrated the lead-acid battery industry as the primary contamination source in the studied areas. There were strong positive relationships (p < 0.01) existed between As, Cd, and Zn in soils and vegetables; while a strong negative association found between As in soils with As in Fruits. The cluster analysis showed EC, OC, OM, Pb, As and Zn into separate group, implied their same source of origin as anthropogenic source. The metal uptake was in the decreasing order of Cd > Zn > As > Pb and Cd > Zn > Pb > As in vegetable and fruit samples, respectively and transfer factor analysis highlighted Cd and Zn as metals with higher absorption rates in vegetables and fruits. Among the industries, AA and AB were significantly impacted on soil quality, and considerable metal accumulation found on vegetables. The human health risk assessment results indicate a potential noncarcinogenic health hazard for the populations surrounding the industries (AA, AB, and AC). This is evidenced by the calculation of the total target hazard quotient and the hazard index, both of which exceeded the acceptable level (>1). However, the carcinogenic health risks arising from the consumption of potentially toxic elements are within threshold values. This study provides crucial insights into the environmental as well as health impact of lead-acid battery industries, emphasizing the urgency of implementing effective environmental management practices to mitigate their consequences.

Exploratory functional data analysis of multivariate densities for the identification of agricultural soil contamination by risk elements

Geochemical mapping of risk element concentrations in soils is performed in many countries around the world. It results in numerous large datasets of high analytical quality, which can be used to identify soils that violate individual legislative limits for safe food production. However, there is a lack of advanced data mining tools that would be suitable for sensitive exploratory data analysis of big data while respecting the natural variability of soil composition. To distinguish anthropogenic contamination from natural variations, the analysis of the entire data distribution for smaller subareas is key. In this article, we propose a new data mining methodology for geochemical mapping data based on functional data analysis of probability densities in the framework of Bayes spaces after post-stratification of a big dataset to smaller districts. The tools we propose allow us to analyse the entire distribution, going well beyond a superficial detection of extreme concentration anomalies. We illustrate the proposed methodology on a dataset gathered according to the Czech national legislation (1990–2009), whose information content has not yet been fully exploited. Taking into account specific properties of probability density functions and recent results for orthogonal decomposition of multivariate densities enabled us to reveal real contamination patterns that were so far only suspected in Czech agricultural soils. We process the above Czech soil composition dataset for Cu, Pb, and Zn by first compartmentalizing it into spatial units, the so-called districts, and by subsequently clustering these districts according to diagnostic features of their uni- and multivariate distributions at high concentration levels. These clusters were seen to correspond to compartments that show known features of contamination, such as historical metallurgy of non-ferrous metals and iron and steel production. Comparison between compartments, notably neighbouring districts with similar natural factors controlling soil variability, is key to the reliable distinction of diffuse contamination. In this work, we used soil contamination by Cu-bearing pesticides as an example for empirical testing of the proposed data mining approach. In general, there are no natural and justifiable thresholds of risk element concentrations that would be valid for geographical areas with too much natural heterogeneity. Therefore, national (or larger) soil geochemistry datasets cannot be processed as a whole. As we demonstrate in this paper, empirical knowledge and careful tailoring of statistical tools for the characteristic types of soil contamination are essential for unequivocal identification of the anthropogenic component in real datasets.

RETRACTED: Proteomic modulation by arsenic and microplastic toxicity in the presence of iron oxide nanoparticles in wheat (Triticum aestivum L.) seedlings

This study provides a detailed biochemical analysis of the toxicity of arsenic (As) and polyvinyl chloride microplastics (PVC−MPs) to soil, and documents how iron oxide nanoparticles (FeO−NPs) can mitigate these effects, with a focus on the proteomic and physiological responses in wheat (Triticum aestivum L.) seedlings, expanding upon existing research in this area. For this purpose, we conducted a pot experiment in which seeds were primed with FeO−NPs at a concentration of 10 mg L−1 under toxic concentrations of As, specifically 150 and 300 mg kg−1, and PVC−MPs at concentrations of 2 and 4 mg L−1. Our results showed that the PVC−MPs and As toxicity in the soil showed a significant decline in the gas exchange attributes, sugars, AsA-GSH cycle, proline metabolism in T. aestivum seedlings. PVC−MPs and As toxicity in T. aestivum seedlings significantly increased oxidative stress biomarkers and both enzymatic and non-enzymatic antioxidants, including their gene expression, while our analysis also incorporates Profilin Quantification for a deeper understanding of the quantitative protein involvement in these processes. Although, the application of FeO−NPs showed a significant increase in the chlorophyll content, gas exchange characteristics, enzymatic and non-enzymatic compounds and their gene expression, AsA-GSH cycle and also decreased the oxidative stress. These results open new insights for sustainable agriculture practices and hold immense promise in addressing the pressing challenges of heavy metal and MPs contamination in agricultural soils.

Critical assessment and recommendations for sewage sludge management in Poland

The purpose of the article is to demonstrate practices used to supervise the use of sewage sludge for agricultural purposes. The presented research and conclusions are a trend analysis and are not to be used to penalise entities. Sewage sludge, which comes from the illegal dumping of wastewater into municipal wastewater by industrial plants, contains large amounts of heavy metals. Treatment plants transfer the sludge for agricultural use. Regulations specifically restrict the mode and conditions for such use of sludge. Methods: the research was carried out using a proprietary questionnaire, which is a supplement to the reporting questionnaire of the National Urban Wastewater Treatment Program implemented by the State Water Company "Wody Polskie". Results: The survey was conducted at 208 wastewater treatment plants in Poland. The results show that the majority of wastewater treatment plants do not properly supervise the process of introducing sewage sludge into the soil. They also lack supervision of how much heavy metals from wastewater are introduced into the soil. This means that there is a very high risk of contamination of agricultural soils. The results obtained could initiate a detailed analysis of this phenomenon in Poland. A comprehensive study of the scale of the practice and its current effects is required to determine the actual condition of soil treated with sewage sludge.

Source-oriented risk assessment of heavy metal(loid)s in agricultural soils around a multimetal smelting area near the Yellow River, China.

Heavy metal(loid) (HM) contamination in agricultural soils, particularly in areas severely impacted by smelting industries, has attracted worldwide attention. In this study, agricultural soils were collected in a flourishing multimetal smelting area near the Yellow River in central China. By an integrated approach encompassing the positive matrix factorization model, ordinary kriging interpolation and hierarchical clustering analysis (PMF-OK-HC), a total of four major sources and their mass contributions were identified, namely, soil parent material (56.6%), industrial waste and Mo smelting (24.0%), metal smelting and traffic emissions (12.8%), and coal combustion (6.7%). On this basis, the health risk of HMs was evaluated by Monte Carlo simulations and showed that a higher risk, with a higher proportion of exceeding-thresholds risk, was observed for children than for adults in terms of both noncarcinogenic and carcinogenic risks. Exposure pathways of oral ingestion in children could result in a higher attributed risk than other pathways. Furthermore, source-oriented risk assessment (SORA) revealed that the sources of coal combustion, industrial waste and Mo smelting had the highest contributions to noncarcinogenic and carcinogenic risks. Overall, for effective environmental management in agricultural soil, the framework of SORA was verified as an effective tool in the identification of the priority control of HMs and their sources.

Heavy metals contamination and ecological risks in agricultural soils of Uşak, western Türkiye: a geostatistical and multivariate analysis.

This research aimed to determine and evaluate the concentrations ofAs, Cu, Hg, Ni, and Pb, and the physicochemical properties of 48 agricultural soil samples, to identify potential ecological risks and their sources associated with heavy metals contamination in Usak, western Türkiye. Various methods were used to assess ecological risks, including geoaccumulation index (Igeo), enrichment factor (EF), degree of contamination (Cdeg), potential ecological risk (RI), and pollution load index (PLI). The heavy metals concentrations ranged from 4 to 61mg/kg for As, 8-48mg/kg for Cu, 0.01-0.06mg/kg for Hg, 30-813mg/kg for Ni, and 4-30mg/kg for Pb. The mean As and Ni concentrations were much greater than Earth's crustal average, the world's mean values, and mean values from many other emerging countries. Igeo and EF values for As, Ni, and Pb indicate various degrees of contamination. Cdeg values show that 96% of the study area is affected to some degree by contamination. For RI values, 38% indicate ecological risks ranging from moderate to considerable degrees. PLI values show that 75% of the agricultural soils are moderately polluted. Spatial distribution maps of Cdeg, RI, and PLI show that the northeastern and southwestern parts of the study area have been polluted to different levels by As, Ni, and Pb. Industrial activities and excessive use of fertilizers, pesticides, fungicides, and herbicides were identified as major sources of heavy metals contamination in the agricultural soils of Uşak.

Characteristics and Migration Dynamics of Microplastics in Agricultural Soils

The risks brought by microplastics (MPs) to agricultural soil structure and crop growth in the agricultural system are the focus of global debate. MPs enter the soil through various routes, such as through the use of agricultural mulch and atmospheric deposition. Here, we review the research on MP pollution in the soil during the last 30 years. This review focuses on (i) the sources, types, and distribution characteristics of MPs in agricultural soils; (ii) the migration and transformation of MPs and their interactions with microorganisms, organic matter, and contaminants in agricultural soils; and (iii) the effects of environmental factors on the composition and structure of MPs in agricultural soils. This review also proposes key directions for the future research and management of MPs in the agricultural soil. We aim to provide a theoretical basis for the fine management of agricultural farmland.

Combined application of biochar and metal-tolerant bacteria alleviates cadmium toxicity by modulating the antioxidant defense mechanism and physicochemical attributes in rice (Oryza sativa L.) grown in cadmium-contaminated soil

Agricultural soil contamination by heavy metal (cadmium) is a widespread issue and causes deleterious effects on crops. One of the most effective and ecofriendly methods for cadmium detoxification is microbe-assisted phytoremediation and soil amendment with biochar. The current study investigated the combined effect of biochar (Parthenium hysterophorus L.) and microbes (Bacillus cereus strain B2) in alleviating cadmium toxicity in rice grown in cadmium-contaminated soil (0, 10, 15, and 20 mg/kg). Results revealed that cadmium caused damage to plant health. Maximum reduction in plant biomass, gas exchange parameters, and chlorophyll content was observed on cadmium 20 mg/kg. As compared with the sole application of biochar (2 %) and microbes, the greatest plant height (33.68%), photosynthetic rate (23.52 %), stomatal conductance (48.93 %), water use efficiency (21.41 %), transpiration rate (58.87 %), chlorophyll a (74.81 %), chlorophyll b (31.28 %), total chlorophyll (60.53 %), and carotenoids (26.97 %) were recorded with combined application of biochar and microbes. Similarly, superoxidase (SOD), catalase (CAT), peroxidase (POD), and absorbate peroxidase (APX) activity was significantly boosted by combined application of microbes and biochar (2 %), which were 33.90 %, 24.18 %, 51.70 %, and 19.06 %, respectively, while significant reduction was found in the ROS (16.60 %), (20.06 %) and MDA (26.08 %) content in rice plants. However, cadmium concentrations in different parts of plant were decreased at higher concentrations of biochar (2 %) with microbes. These findings indicate that combined application of Bacillus cereus strain B2 and biochar could be a promising strategy for reducing rice crop cadmium toxicity and boosting its growth, physiology, and defense system efficiently as compared with sole application.

Characteristics and evaluation of heavy metal pollution in a soil–wheat system of an arid oasis city in northwest China

In this paper, the Cu and Ni accumulation and contamination levels in agricultural soils and wheat around a smelter in Jinchang City in northwest China were investigated with a combination of field investigations and indoor analytical tests, using a soil–wheat system as the study area. The average Cu and Ni contents in the soil were 119.50 mg kg–1 and 123.40 mg kg–1, respectively, both of which exceeded the local soil background values. The Cu and Ni contents in 46.15% o and 26.92% of sampling sites, respectively, exceeded the screening values for soil contamination risk in agricultural land in China. The average Cu content in different parts of wheat was in the order of roots (24.22 mg kg–1) > leaves (20.11 mg kg–1) > husks (5.51 mg kg–1) > grains (4.05 mg kg–1) > stalks (3.74 mg kg–1). Furthermore, the average Ni content ranked as leaves (24.64 mg kg–1) > roots (21.12 mg kg–1) > husks (6.95 mg kg–1) > stalks (1.75 mg kg–1) > grains (0.38 mg kg–1). The health risk evaluation showed that with average hazard index values of 0.88 for adults and 1.04 for children for Cu and Ni in wheat grain, wheat in this region is unlikely to pose a health risk to adults but may pose a lesser health risk to children. The Ni bio–concentration and translocation factors in the husk and leaves of wheat were greater than those of Cu and smaller than those of Cu in the other parts of wheat. The results of this study provide basic data for the remediation of heavy metal contamination in local agricultural soils.

Nanoparticles synergy: Enhancing wheat (Triticum aestivum L.) cadmium tolerance with iron oxide and selenium

Nanotechnology is capturing great interest worldwide due to their stirring applications in various fields and also individual application of iron oxide nanoparticle (FeO − NPs) and selenium nanoparticles (Se − NPs) have been studied in many literatures. However, the combined application of FeO and Se − NPs is a novel approach and studied in only few studies. For this purpose, a pot experiment was conducted to examine various growth and biochemical parameters in wheat (Triticum aestivum L.) under the toxic concentration of cadmium (Cd) i.e., 50 mg kg−1 which were primed with combined application of two levels of FeO and Se − NPs i.e., 15 and 30 mg L−1 respectively. The results showed that the Cd toxicity in the soil showed a significantly (P < 0.05) declined in the growth, gas exchange attributes, sugars, AsA-GSH cycle, cellular fractionation, proline metabolism in T. aestivum. However, Cd toxicity significantly (P < 0.05) increased oxidative stress biomarkers, enzymatic and non-enzymatic antioxidants including their gene expression in T. aestivum. Although, the application of FeO and Se − NPs showed a significant (P < 0.05) increase in the plant growth and biomass, gas exchange characteristics, enzymatic and non-enzymatic compounds and their gene expression and also decreased the oxidative stress, and Cd uptake. In addition, individual or combined application of FeO and Se − NPs enhanced the cellular fractionation and decreases the proline metabolism and AsA − GSH cycle in T. aestivum. These results open new insights for sustainable agriculture practices and hold immense promise in addressing the pressing challenges of heavy metal contamination in agricultural soils.

Combined exposure of PVC-microplastic and mercury chloride (HgCl2) in sorghum (Pennisetum glaucum L.) when its seeds are primed titanium dioxide nanoparticles (TiO2-NPs).

The present work studied the impact of different levels of PVC-microplastics (PVC-MPs), namely 0 (no PVC-MPs), 2, and 4mg L-1, along with mercury (Hg) levels of 0 (no Hg), 10, and 25mgkg-1 in the soil, while concurrently applying titanium dioxide-nanoparticles (TiO2-NPs) at 0 (no TiO2-NPs), 50, and 100µgmL-1 to sorghum (Pennisetum glaucum L.) plants. This study aimed to examine plant growth and biomass, photosynthetic pigments and gas exchange characteristics, oxidative stress indicators, and the response of various antioxidants (enzymatic and non-enzymatic) and their specific gene expression, proline metabolism, the AsA-GSH cycle, and cellular fractionation in the plants. The research outcomes indicated that elevated levels of PVC-MPs and Hg stress in the soil notably reduced plant growth and biomass, photosynthetic pigments, and gas exchange attributes. However, PVC-MPs and Hg stress also induced oxidative stress in the roots and shoots of the plants by increasing malondialdehyde (MDA), hydrogen peroxide (H2O2), and electrolyte leakage (EL) which also induced increased compounds of various enzymatic and non-enzymatic antioxidants and also the gene expression and sugar content. Furthermore, a significant increase in proline metabolism, the AsA-GSH cycle, and the pigmentation of cellular components was observed. Although, the application of TiO2-NPs showed a significant increase in plant growth and biomass, gas exchange characteristics, enzymatic and non-enzymatic compounds, and their gene expression and also decreased oxidative stress. In addition, the application of TiO2-NPs enhanced cellular fractionation and decreased the proline metabolism and AsA-GSH cycle in P. glaucum plants. These results open new insights for sustainable agriculture practices and hold immense promise in addressing the pressing challenges of heavy metal contamination in agricultural soils.

Assessment of potential ecological risk of heavy metal contamination of agricultural soils in Kazakhstan.

Accumulation of heavy metals in soil can lead to the deterioration of soil quality, reduce soil fertility and crop yields, and thus threaten human and animal health. The study aimed to assess the potential ecological risk of heavy metal contamination of agricultural soils in Kazakhstan. The study was carried out in 2021 on the soils of the Zhdanovskoye owner-operated farm in the Sokolovsko-Sarybai district of the Kostanay region. The quantitative content of heavy metals, such as lead (Pb), mercury (Hg), arsenic (As), and cadmium (Cd), was determined, and concentrations of trace elements, such as zinc (Zn), copper (Cu), iron (Fe), and manganese (Mn), were calculated for the considered contaminated lands. The potential ecological risk index (RI) proposed by L. Hakanson was used in the study concerning heavy metal contamination of soil. As a result, the presence of trace elements and heavy metals in the considered areas of the Kostanay region was shown. The RI values for all sites ranged from 137 to 447, corresponding to the level of ecological risk grading from low to high. The average RI for As, Cd, Hg, Pb, Zn, Ni, and Cu amounted to 328, which indicates a high ecological risk. Detected levels of As, Cd, Zn, and Pb in long-term abandoned mining areas were well above national thresholds, indicating the impending need to fully investigate and assess the suitability of the land for further agricultural use. The availability of such data will allow predicting cluster-based development of processing infrastructures in the vicinity of agricultural lands.

Selenium Nanoparticles Improves Morpho-Physio-Biochemical Traits and Cadmium Stress Tolerance in Garden Mint using Seedling Root Dip Feeding

Due to extensive global contamination of agricultural soils with cadmium (Cd), there is a dire need for cost-effective and practical methods to ensure the production of safe food. The recent introduction of micronutrients in nano form has been found to reduce the accumulation of Cd in crops. A greenhouse pot-culture experiment was done to investigate the effects of selenium nanoparticles (0, 10, 20 and 30 mgL-1) applied by seedling root dipping technique on the growth, biomass, physio-biochemical and antioxidant potential of mint grown under induced cadmium stress (25 mg kg-1of soil using CdCl2). Findings revealed that application of selenium nanoparticles considerably improved tissues biomass, photosynthesis, and antioxidant enzyme activities in the mint plants. In addition, the application of Se nanoparticles in optimal concentration improved the relative water contents (7.26%), and decreased the electrolyte leakage (32.96%) in plant tissues. Selenium nanoparticles exhibited a dose-additive effect in reducing the levels of malondialdehyde cadmium in tissues of mint plants. Selenium nanoparticles at 20 mg L-1 demonstrated more efficacy than other levels under control and Cd stressed conditions. These findings indicate that seedling root dip feeding of selenium nanoparticles is an efficient approach and could be recommended for remediation of Cd contaminated soils.

Impacts of long-term irrigation with coalmine effluent contaminated water on trace metal contamination of topsoil and potato tubers in Dinajpur area, Bangladesh

Rapid depletion of groundwater and climate change mediated shifting precipitation pattern is forcing farmers to look for alternative irrigation options like wastewater. However, routine irrigation with trace metal contaminated wastewaters could potentially pollute soil as well as cause health risks through the consumption of food products grown in contaminated soil. Thus, the present study aimed to investigate the trace metals build-up status in topsoil and potato (Solanum tuberosum L.) tubers upon continuous irrigation with coalmine effluent contaminated wastewater compared to irrigation with groundwater and surface water over three consecutive years. Soil pollution status and human health risk associated with consumption of potato tubers grown on wastewater-irrigated soil was also assessed in this study. Three separate experimental sites differing in irrigation source (groundwater, surface water, and coalmine wastewater) were selected near Barapukuria Coal Mining Company Limited located at Parbatipur upazilla of Dinajpur district, Bangladesh. Nine trace metals namely arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), iron (Fe), manganese (Mn), nickel (Ni), lead (Pb), and zinc (Zn) were estimated. Results showed significantly higher trace metal content in both soil and potato tubers due to wastewater irrigation. Wastewater suitability for irrigation regarding Cd, Cr, Cu, Fe, Ni and Pb were off the permissible level although the soil contamination with trace metals and their levels in potato tubers remained within the safety limit. Health risk assessment revealed that, consumption of potato tubers grown in wastewater-irrigated soil remained safe although health risk associated with Cr was almost at the border. The study exclusively highlighted the core massage that, trace metal contamination of both soil and potatoes cultivated in them was increasing alarmingly due to three years of wastewater-irrigation. Although the extent of contamination was below critical limit, it can potentially become hazardous in years to come unless wastewater-irrigation is checked. This study was successful to provide valuable insights regarding the potential environmental and human health threats that might arise due to unmindful irrigation of contaminated coalmine wastewater. Besides, this study should prove useful in strategizing safety measures for cropping under trace metal contaminated soils and for planning industrial effluent disposal to avoid agricultural soil contamination.

Quantification of Pollution Index of Selected Heavy Metals in Agricultural Soils in Kafin Hausa Area, Northwest Nigeria

In this study, the level of heavy metals contamination in agricultural soils in Kafin Hausa, Nigeria, was investigated and characterised using the Instrumental Neutron Activation Analysis technique via the Nigeria Research Reactor-1. Fifteen soil samples were collected from five different sampling sites and analysed for eight heavy metals: aluminium (Al), arsenic (As), barium (Ba), iron (Fe), holmium (Ho), potassium (K), magnesium (Mg), and rubidium (Rb). Heavy metal pollution indices were estimated using the geo-accumulation index (Igeo), enrichment factor (EF), contamination factor (CF), and pollution load index (PLI). The results showed that the mean Igeo indexes of Al (-3.09), As (-4.88), Ba (-0.89), Fe (-3.53), K (-2.20), and Mg (-4.95) were lower than zero, indicating that the soil of the studied region was uncontaminated by these metals. The mean EF of Ho was significantly higher than other metals, indicating that the soil is enriched with this metal. As (0.40) and Mg (0.36) had the lowest EF values. Similarly, the mean CF of all metals was lower than 1, suggesting minimal or low contamination. In contrast, Ho (1.60) exhibits the highest CF value, signifying moderate contamination. The PLI values for all metals were between 0.16 and 0.51, indicating that the studied area is unpolluted. There are strong correlations between all the elements, with p-values at 0.01 level, particularly for K – Rb, Ba – K, and Ba – Rb, with values ranging from 0.94 to 0.94. Hence, the results of this study suggest that the agricultural soils in Kafin Hausa are uncontaminated by heavy metals.