Potentially Toxic Elements Concentrations Research Articles

Occupational and human health risks of exposure to potentially toxic elements (PTEs) in top soils from steel fabrication workshops

IntroductionEnvironmental pollution caused by potentially toxic elements (PTEs) from anthropogenic sources has become a global concern due to its deleterious effect on humans and ecosystem health. Therefore, this study evaluated the concentrations of PTEs, pollution level and human health risk in topsoil from ten (10) steel fabrication workshops in Abeokuta, Ogun State, Nigeria. Materials and methodsTen (10) composite soil samples were collected in November 2023, from 10 different steel fabrication workshops in proximity to residence in Abeokuta, Ogun State, Nigeria. One (1) gram of processed sample was digested using aqua regia and PTE concentration estimated using atomic absorption spectrophotometer (AAS). Pollution index assessment was determined using enrichment factor (EF) and geo-accumulation index (I-geo) while descriptive statistics and correlation were subjected to statistical package for social sciences (SPSS). ResultsThe result showed that Iron (Fe) (11,500 – 42,100 mg kg−1), Lead (Pb) (10.7 – 583 mg kg−1), Chromium (Cr) (16.3 - 49.7 mg kg−1), Zinc (Zn) (34.6 – 343 mg kg−1), Manganese (Mn) (109 – 840 mg kg−1), Nickel (Ni) (2.23 - 25.3 mg kg−1), Copper (Cu) (16.6 -107 mg kg−1) and Cadmium (Cd) (2.23 - 25.3 mg kg−1) were present. Mean concentration for Pb (179±202 mg kg−1) is higher than the Canada soil guideline value (CSGV) (140 mg kg−1) while other PTEs are within the recommended limit. Pollution indices revealed EF (Cd and Pb) and I-geo (Cd) as the primary pollutants in the soil while the strong significant correlation between Cr, Cu and Mn p < 0.05. Cr, Ni, Pb and that of Cu, Mn, Ni, Pb, Zn p < 0.01 suggest an emanation from both geogenic and anthropogenic sources. Human health risk assessment revealed Fe as the most dosed PTE and ingestion as the major pathways of exposure especially to children being the most susceptible. Hazard index (HI) and total cancer risk (TCR) values for PTEs were <1 and within the acceptable threshold (1 × 10−6 – 1 × 10−4) except for Pb (3.93E+01; 1.16E-03) in adults respectively. ConclusionThe study showed that the topsoil from the steel fabrication workshop is polluted with Pb and Cu toxicity and the adult (residents and workers) population exposed to the soil is potentially at a non-cancer and cancer risk.

Source apportionment, ecological and health risk assessment of potentially toxic elements in water, sediment and blackchin tilapia {Sarotherodon melanotheron (Rüppell 1852)} from Lagos and Ologe Lagoons, Lagos State, Nigeria

BackgroundLagos and Ologe Lagoons are parts of the Lagos Lagoon Complex, which provide fish as an animal protein source to the locals. However, these fish species have a high propensity to accumulate pollutants including Potentially Toxic Elements (PTEs) from their environment. This potentially constitutes a health risk to fish consumers. Therefore, this study investigated concentrations of some PTEs (As, Cd, Cr, Cu, Fe, Pb, Ni, and Zn) in water, sediment, and fish (Sarotherodon melanotheron) from Lagos and Ologe Lagoons, the ecological and health risks associated with the consumption of the fish as well as the likely sources of the PTEs. MethodsWater, sediment, and fish (S. melanotheron) samples were collected monthly for ten months (June 2022 - March 2023) from three sites: Badore and Baiyeku in Lagos Lagoon and Ologe Lagoon. The concentration of PTEs was determined in the environmental matrices {water, sediment, and three organs (gill, muscle, liver)}. The range of values for method detection limits (MDL), limits of detection (LOD), limits of quantitation (LOQ), and recovery rates were 0.01 – 0.025 mg kg−1, 0.00002 – 0.002 mg L−1, 0.0001 – 0.0067 mg L−1 and 97.19±2.45 - 99.85±1.16% respectively. The ecological risk of PTE in water and sediment was assessed by various indices. Estimated dietary intake (EDI), health risk index (HRI), and target hazard quotient (THQ) were the human health risk assessment indices employed. The distribution and source of the PTEs were analyzed using the coefficient of variation, Pearson's correlation matrix, principal components analysis, and hierarchical cluster analysis. ResultsThe water and sediment quality assessment indices indicated that the water and sediment from the lagoons had low contamination with respect to the eight PTEs studied. EDI values were generally less than 1 except for Fe and Zn. THQ for all PTEs in the three sampling stations and across the different population groups was less than 1 except for Fe. PCA revealed two major sources of PTE pollution which are natural and anthropogenic. As, Cd, Cr, Cu, and Pb were probably due to anthropogenic inputs like agricultural operations and industrial activities while Fe, Ni, and Zn may have occurred due to lithological sources like rock weathering and volcanic events. ConclusionBased on the result of the study, the waters from the lagoons are still suitable for agricultural usage. The sediments are also largely uncontaminated with respect to the eight PTEs studied. The EDI and THQ show that consumption of S. melanotheron from the sites may not constitute any significant health risk to humans and the sources of the PTEs are lithologic and anthropogenic.

Spatial distribution of potentially toxic elements pollution and ecotoxicological risk of sediments in the high-altitude lakes ecosystem

Sediments are a sink and source for potentially toxic elements (PTE) contamination in aquatic systems. Among aquatic systems, lakes ecosystem play a significant role in managing, maintaining, and supplying water for several environmental and ecological services. The lake has a slow rate of water inflowing contaminant circulation, building up higher contaminants and hence making it most vulnerable. This study focused on and explored the sediments for PTE concentrations in the high-altitude lakes ecosystem of Swat Valley, northern Pakistan. The sediment samples were collected and analyzed for PTE concentrations. Among PTE, iron (Fe) showed an uppermost level of 1024 ± 94.2 mg/kg in Izmis Lake sediments, while cadmium (Cd) noted with a lowermost of 0.30 ± 0.1 mg/kg in Kandol Lake. PTE concentrations in the high-altitude lakes were noted to be lower than the sediment quality guidelines (SQGs), except for copper (Cu) and cadmium (Cd). The concentrations of PTE were utilized to calculate pollution factors and ecotoxicological risks. The contamination factor (Cf) of sediments in high-altitude lakes observed low to moderate contamination levels and ecotoxicological risks. Among high-altitude lakes, the Izmis Lake showed maximum Cf, pollution load index, and risk values for most of PTE than others. Statistical analyses revealed a significant correlation for most PTE and noted geogenic sources of contamination in sediments of high-altitude lakes.

Potentially toxic elements concentration and distribution in soils around artisan workshops in Ago-Iwoye, Southwestern Nigeria

Background/IntroductionAnthropogenic activities, including those carried out by artisans, have been confirmed to be one of the various means by which potentially toxic elements (PTE) are introduced into the soil. This study aims to determine the PTE concentration and distribution in soils around artisans workshops in Ago-Iwoye, southwestern Nigeria. MethodsTwenty (20) soil samples comprising ten (10) samples from soil around auto-mechanic workshops, six (6) from soils around vulcanizer workshops and four (4) from soils around welder workshops were collected and analyzed for elemental concentration using Inductively Coupled Plasma Mass Spectrometry (ICP-MS). ResultsElemental analysis revealed the following trend for selected metals in auto-mechanic, vulcanizing and welding workshops, respectively: Ba (60–100, 100–200 and 130–590 mg.kg−1); Co (10–47, 8–19 and 15–37 mg.kg−1); Cr (29–161, 22–95 and 57–272 mg.kg−1); Cu (28–123, 16–100 and 88–486 mg.kg−1); Ni (11–33, 7–29 and 34–112 mg.kg−1); Pb (17–75, 12–77 and 36–677 mg.kg−1); Sc (2–16, 1–7 and 2–8 mg.kg−1); Sr (13–55, 17–72 and 33–91 mg.kg−1); V (35–212, 20–117 and 40–103 mg.kg−1) and Zn (82–684, 70–548 and 314–3240 mg.kg−1). Geochemical assessment using contamination factor, and geo-accumulation index showed that the artisanal workshops exhibited significant contamination levels for metals such as Ba, Cu, Ni, Pb, Sr, and Zn and the contamination level varied across the artisan workshops with soils around welders workshops showing highest contamination. ConclusionContamination indices revealed the artisan workshops have varying contribution to the metal load in the area and Pollution Load Index (PLI) indicated a decline in soil quality across all artisanal workshops with welding workshops revealing the highest anthropogenic contribution of PTE to the soil.

Geochemical Signature and Risk Assessment of Potential Toxic Elements in Intensively Cultivated Soils of South-West Punjab, India

Soil contamination with potentially toxic elements (PTEs) in the Malwa region belt of Punjab, India, can be a serious concern as a result of intensive agricultural practices and overuse of agrochemicals. The main objectives of the present study were to evaluate the spatial distribution, geochemical signature, and contamination level/health risk of PTEs in 76 soil samples (0–10 cm) collected from the three districts viz. Muktar, Faridkot, and Moga of Punjab, India. The result shows that PTEs concentrations vary widely in the region, with Fe and Mn distribution patterns being mostly coherent with each other. When compared to the Indian natural soil background values, the average concentration of Pb and Zn were higher than the limit, only Pb exceeded the average values of the world background and upper continental crust (UCC). Spatial autocorrelation plotted with a local indicator of spatial association (LISA) in GeoDa software version 1.18 was used to identify hotspots. A positive spatial autocorrelation (&gt;0.2) was indicated with Moran’s I values for Pb, V, Mn, Cu, and Cr, being highest for Pb. A principal component analysis (PCA) identified the major geo-chemical patterns of Fe-Al-V-Cr and TOC-Mn-Zn-HCO3−, which were positively loaded on PC1. This indicates that Fe/Al-oxyhydroxides and organic matter play a dominant role in controlling metal mobility in soils. This can be further substantiated with the Spearman’s rank correlation values. The contamination factor (CF) indicates that only Pb and Zn (15.7% and 3.9% samples, respectively) were under high risk. This could be due to the excessive application of chemical fertilizers. The large range of degree of contamination (Cdeg) values suggests that there are variations in the degree of soil pollution due to PTEs. A little over 3.9% of samples had significant contamination, compared to 72.3% of samples with low contamination and 23.6% of samples with moderate contamination. Human non-carcinogenic and carcinogenic risk levels were investigated. The hazard index (HI) values for adult ranged from 0.00 to 0.2, and values for children ranged from 0.009 to 1.2. These findings suggest that both children and adults are not at potential risk, except in a few locations. Overall, the results of this study provide the current baseline status of toxic elements in agricultural soil. This would be helpful for developing strategies for sustainable management of the soil resources in the region, as well as for future monitoring programs of the soil quality in the Malwa region as a whole, to track any changes in the contamination levels over time.

Spatiotemporal Distribution Characteristics and Influencing Factors of Dissolved Potentially Toxic Elements along Guangdong Coastal Water, South China

In this study, five potentially toxic elements (PTEs) (Hg, Pb, As, Zn, and Cu) and five physicochemical factors (pH, dissolved oxygen, salinity, chlorophyll a, and chemical oxygen demand) relating to surface seawater were measured along the coast of Guangdong Province (GD), China, during three seasons in 2019. Comprehensive analyses were conducted to explore the distribution characteristics, pollution degrees, and influencing factors of PTE. The results showed that the concentrations of PTE varied spatially and seasonally due to these elements’ complex sources and behaviors. Pb was the most abundant toxic element, reaching considerable contamination levels. Overall, the average pollution degrees of Cu, As, and Zn were higher around the east coast of GD, while Hg and Pb levels were higher in the west coast region of GD. The correlation analysis showed that the variation of different physicochemical parameters had different degrees of influence on PTE transport and transformation. This study can help environmental managers gain deeper insight into the influence of complex factors on PTE and improve the efficiency of pollution control in this significant subtropical coastal area.

Human and ecological risk assessments of potentially toxic elements in sediments around a pharmaceutical industry

Potentially toxic elements (PTEs) in sediment can be highly hazardous to the environment and public health. This study aimed to assess the human and ecological risks of PTEs in sediments around a pharmaceutical industry in Ilorin, Nigeria. Physicochemical parameters and the concentrations of lead (Pb), chromium (Cr), cadmium (Cd), cobalt (Co), arsenic (As), and nickel (Ni) were analyzed in sediment samples collected from seven locations in the wet and dry seasons. Standard two-dimensional principal component analysis (PCA) and risk assessments were also conducted. The concentrations of Pb, Co, Ni, Cr, Cd, and As in the sediments ranged from 0.001 to 0.031 mg/kg, 0–0.005 mg/kg, 0.005–0.012 mg/kg, 0.001–0.014 mg/kg, 0.005–0.024 mg/kg, and 0.001–0.012 mg/kg, respectively. The mean concentrations of the total PTEs content were found in decreasing order of concentration: Pb > Cd > Ni > Cr > As > Co. PCA showed that some of the PTEs were highly concentrated in samples obtained at other locations as well as at the discharge point. The Hazard Index was mostly <1 across locations, indicating little to no probable non-cancerous effect. However, the incremental lifetime cancer risk for arsenic and nickel was high and required attention. The ecological risk assessment showed that lead and arsenic were the major PTEs pollutants in all locations. The study identifies PTEs profiles in sediments and emphasises the necessity of continual monitoring and action to stop long-term negative impacts on the local environment and public health.

Fate, source apportionment and fractionation of potentially toxic elements in agricultural soil around a densely populated, semiarid urban center of India: baseline study and ecological risk assessment.

This study is on the outskirts of the rapidly growing city of Jaipur, located in the semiarid region of India and gateway to the 'Great Indian Thar' desert, and focused on potentially toxic elements (PTE) pollution in the farmlands around the city. Concentrations of PTE, along with associated soil parameters such as pH, available nitrogen, organic carbon, phosphorus, and potassium, were estimated in agricultural soil samples near an industrial region on the outskirts of the capital city of the largest state of India. The PTE concentrations in the soil were in the following order: Mn > Pb > Ni > Cr > Cu > Cd. Soil pollution indices, such as the geochemical accumulation index (Igeo), contamination factor (CF), and ecological risk index (ERI), indicated that the soil was moderately to highly polluted. The result of BCR extraction techniques showed Cd is found mainly in the exchangeable and residual fractions, Pb, Mn were found in the reducible as well as residual fractions, while other PTE were mostly bound to residual fraction. All other PTEs are primarily found in the residual fraction, tightly linked with the silicate lattice of soil minerals. Multivariate analysis and the Pearson correlation matrix indicate a common source apportionment for Pb and Cd. Cd, and Pb concentrations in agricultural soil indicate ecological harm that warrants immediate attention and policy-level intervention.

Concentration of Potentially Toxic Elements (PTEs) in Rapid Coffee Products in Bandar Abbas, Iran: Probabilistic Non-Carcinogenic and Carcinogenic Risk Assessment.

Coffee is one of the most widely consumed beverages in the world. However, coffee plants are often exposed to potentially toxic elements (PTEs) pollution. The main aims of current study were to detect the PTEs in instant coffee and health risk assessment of consumers in Bandar Abbas city. To achieve this, 40 samples of instant coffee were randomly collected from various points in the city in 2023 and PTEs concentrations were measured using flame atomic absorption spectrometry (FAAS). The non-carcinogenic and carcinogenic risks were calculated using Monte Carlo simulation (MCS) method. The concentrations of Fe and Cu were higher than other PTEs, equaling 404.41 mg/kg and 0.0046 mg/kg, respectively. The non-carcinogenic risk assessment revealed that THQ (Fe > Pb > As > Cd > Ni > Cu) and TTHQ levels were less than 1 based on the 95% percentile in adults and children, indicating there is no possibility of a non-carcinogenic risk associated with instant coffee. The carcinogenic risk due to inorganic As in instant coffee was acceptable (2.63E-5 and 1.27E-5 based on the 95% percentile for adults and children, respectively), therefore PTEs in instant coffee do not endanger the health of consumers.

Identification of spatial clusters of potentially toxic elements in different soil types using unsupervised machine learning and compositional data analysis

Soil health is important, with soil chemical composition data, including potentially toxic elements (PTEs) being one of its conceptual components. This study aims to reveal the spatial distribution patterns of soil PTEs contents, identify their potential sources, and unveil their geochemical associations in Aragatsotn region, Armenia. For that purpose, the contents of Cr, V, Ti, As, Zn, Cu, Co, Fe, Mn, Ba, and Pb were determined using an X-ray fluorescence spectrometer. The mean contents of Cr and As exceeded their upper continental crust by 1.5 and 3.1 times and their maximum acceptable values by 1.5 and 1.5 times. The analysis demonstrated the presence of sites where all these elements displayed comparatively higher values. The combined application of compositional data analysis and geospatial mapping revealed multivariate outliers, which were located in structural-metallogenic zones with active ore exploitation . The application of unsupervised machine learning algorithm unveiled three groups within the main dataset and the clr-biplot identified the source-specific elements. Particularly, Group I included Cu and displayed the highest mean value among the identified groups. The soil samples included in Group I were in areas where Calcisols were developed and comparatively high Cu contents were attributed to agricultural activities and vehicle emissions. Group II is represented by the geochemical association of Fe, Co, Cr, Mn, Zn, and As. The formation of this group is conditioned by volcanic rocks of the local geological origin. However, no spatial pattern was identified in Group II distribution aligned with soil types. Group III included Ti, V, Pb, and Ba, which may have a mixed origin as it is spatially distributed in areas where regional highways pass through and where Group II elements also exhibit their higher values.

Assessment of macro, trace and toxic element intake from rice: differences between cultivars, pigmented and non-pigmented rice

Pigmented and non-pigmented rice varieties (grown in different areas) were collected in China, Yunnan, to investigate the content of macro-, trace elements and potentially toxic elements (PTEs), and to assess the health risk associated with dietary intake. The order of elemental concentrations in rice was Mn > Zn > Fe > Cu > Se for trace elements, P > K > Mg > Ca > Na for macro elements, and Cr > As > Cd for PTEs. Rice with a high concentration of essential elements also associated with a high content of PTEs. In addition, higher content of Cr, Mn and Na were found in pigmented rice. The health risk assessment showed that the daily intake of all elements was below the tolerable limit (UL). Moreover the intake of Fe, Zn and Se was far from sufficient for the nutrient requirement. The PTEs in rice dominated the health risk. Of concern is that this rice consumption is likely to contribute to carcinogenic risks in the long term and that adults are at higher health risk from pigmented rice compared to non-pigmented rice. This study confirms that the lack of essential micronutrients in rice and the health risk associated with rice diets should remain a concern.

Is it healthy urban agriculture? Human exposure to potentially toxic elements in urban gardens from Andalusia, Spain

Different vegetable species and topsoils were collected from different urban gardens of Seville, Cordoba, and Huelva (South Spain) and from two small towns in a mining area (Riotinto), together with topsoil close to the plants. The concentration of potentially toxic elements (PTEs) (As, B, Ba, Cd, Co, Cr, Cu, Mo, Ni, Pb, and Zn) was evaluated in edible plant parts and in the soils. The same species were also purchased from Seville local markets and from a peri-urban area (domestic garden in a rural area) and also analyzed. Plant/soil pollution relation was studied and human health risk was assessed by different parameters. Soils of urban gardens from the mining area were more contaminated with As, Cr, Cu, Pb, and Zn in comparison with other locations, and generally, soils from cities showed higher values of As, Pb, and Zn than the peri-urban ones. The mean concentration of almost all potentially toxic elements was higher in leafy than in fruiting and bulbous species. Arsenic, Cd, and Pb concentrations were below health-based guidance values in all vegetables except Cd in one sample in the peri-urban area. In general, PTEs concentration in vegetables from city urban gardens did not exceed the one found in market vegetables for almost all studied elements, except in lettuce for almost elements. The hazard quotient (HQ) values were lower than the unit for all PTEs in plant species from the studied gardens, as well as the hazard index (HI), indicating that consumption of these vegetables can be considered safe and without risk to human health. Also, cancer risk values for As were below the established limits in all vegetables from the studied urban gardens, including those from the As-contaminated soils in the mining area.

Bioavailability, risk assessment, and source traceability of potentially toxic elements in bivalve species widely consumed in the emblematic Acapulco Bay, Mexico

The concentration of potentially toxic elements (PTE) was determined in edible tissue, digestive system, and shells of two bivalve species (Hyotissa hyotis and Spondylus limbatus) highly consumed in Acapulco Bay (southern Mexico) to evaluate the impact on marine ecosystems and human health risk associated with the consumption of potentially contaminated bivalves. PTE concentrations (Ba–Cd–Cu–Co–Cr–Mn–Ni–Pb–Sr–V–Zn) in edible tissues were lower than in the digestive system and shells in both bivalve species. Except for Cr, Pb, and Cd, PTE concentrations in the edible tissue of both species did not exceed international threshold limits. In addition, the biota-sediment accumulation factor values indicate bioaccumulation in edible tissues (Ni, Cd, Pb, Co, and Zn), digestive system (V, Ni, Cu, Cd, Pb, Co, and Zn), and shells (V, Cr, Pb, Co, and Mn), evidencing availability of pollutants in the Acapulco Bay. Contents of Pb and Cd found in edible tissue can threaten human health. Target Hazard Quotient values indicate that the consumption of edible tissue does not represent any risk of developing non-cancerogenic effects. However, the Target Cancer Risk values indicate a moderate risk of developing carcinogenic effects due to the accumulation of Cr and Pb and an even greater risk due to the accumulation of Cd. Additionally, although local rocks and sediments should be the only source of PTE in uncontaminated marine ecosystems, a low radiogenic Pb isotope composition was detected in the bivalve shells, which partially overlap with Pb isotope compositions of paints and gasoline, indicating anthropogenic lead sources participation in the Acapulco Bay.

Evaluation of potentially toxic elements and microplastics in the water treatment facility

The potentially harmful effects of consuming potentially toxic elements (PTEs) and microplastics (MPs) regularly via drinking water are a significant cause for worry. This study investigated PTEs (Cd, Cu, Cr, Ni, Pd, Zn, Co), MPs, turbidity, pH, conductivity, and health risk assessment in the water treatment plant in Kielce, Poland. Zn had the highest concentrations throughout the water treatment facility, whereas Cd, Pb, and Co had lower concentrations (< 0.1 µg/L). The order of the concentrations among the specified PTEs was like Zn˃Cu˃Ni˃Cr˃Cd˃Pb and Co. The minimum turbidity was 0.34, and the maximum was 1.9 NTU. The range of pH in water samples was 6.51—7.47. The conductivity was 1,203—1,445 ms in water samples. These identified MPs were categorized into fiber and fragments. The color of these identified MPs was blue, red, black, green, and transparent. The minimum and maximum size of the MPs was 196 and 4,018 µm, while the average size was 2,751 ± 1,905 µm. The average concentration of MPs per liter of the water treatment plant was 108.88 ± 55.61. The elements listed are C, O, Na, Mg, Al, Si, K, Ca, and Ti. Fe and Zn were the predominant elements seen using EDX. HQ values of the PTEs were less than one for adults and children. The human health risk associated with all detected PTEs revealed that the HQ values exhibit a satisfactory degree of non-carcinogenic adverse health risk. HI values for adults and children age groups were less than one. In most water treatment samples, the carcinogenic value exceeds the threshold value of 10−6. The PTEs and MP concentrations in drinking water should be periodically monitored to minimize consumers' environmental pollution and health risks.

A multisensor approach coupled with multivariate statistics and geostatistics for assessing the status of land degradation: The case of soils contaminated in a former outdoor shooting range

Soil contamination in outdoor shooting ranges (OSRs) is a major threat for human health, particularly when, after the end of activities, the land is used for recreational areas or agricultural production. The status of land degradation of an OSR in southern Italy was assessed using a multisensor approach. It was based on: i) proximal sensors, including electromagnetic induction (EMI) for measuring soil electrical conductivity (ECa) and magnetic susceptibility (MSa), γ-ray spectrometry for K, eU and eTh analyses and ultrasonic penetrometry detecting cone index (CI) data representative of soil's strength, ii) field surveys on soil thickness (ST), and iii) laboratory analyses of potentially-toxic-elements (PTEs) by portable X-ray fluorescence spectrometry and polycyclic aromatic hydrocarbons (PAHs) by gas-chromatography. Spatial variability of measurements was modelled and mapped using geostatistical methods. The most densely measured covariate (i.e., the ECa of the topsoil) was used within kriging with external drift to improve the PTEs predictions. The PTEs maps were complemented by maps of spatial uncertainty. A robust multivariate principal component analysis (rPCA) was applied to proximal sensor and laboratory data and allowed to identify associations of PAHs, lead, CI with the topsoil ECa along the first component (PC1), highlighting the correlation between land anthropogenic effects and EMI measures; while the association between the ST (estimating the depth of underground travertine hard-layers) and the bottom soil ECa and MSa along the second component (PC2) evidenced the influence of soil stratigraphy on the EMI measures. This study demonstrates that the simultaneous use of different proximal sensors associated with laboratory analysis can allow to assess and model the spatial variability of the land degradation status of an OSR, including soil compaction, organic and inorganic contamination. The correlation between EMI data with the PTEs content highlights the potential of this technique in the field of soil contamination.

Assessment of potentially toxic elements and health risks of agricultural soil in Southwest Riyadh, Saudi Arabia

Abstract The rise of emerging pollutants in the environment as a result of economic growth poses a worldwide challenge for the management of environmental and human health. The objective of this study was to assess the presence of potentially toxic elements (PTEs) in the agricultural soil of southwest Riyadh, Saudi Arabia, and to evaluate the potential health risks associated with these elements. Soil samples were collected from 31 farms, and the concentrations of As, Pb, Cu, Ni, Zn, and Fe were analyzed using inductively coupled plasma-atomic emission spectrometry. Various contamination and health risk indices, along with multivariate analyses, were employed in the evaluation. The mean concentrations of PTEs (mg/kg) followed the order: Fe (15,556) &gt; Zn (53.36) &gt; Ni (21.78) &gt; Cu (11.92) &gt; Pb (10.42) &gt; As (2.64). The average PTE concentrations were found to be lower than background levels and the world-soil average. Contamination indices indicated that the studied soil was moderately enriched and contaminated for As, slightly enriched for Zn and Ni, and not enriched for Cu and Pb. This suggests that the PTEs in the soil do not pose a significant threat, although some individual samples exhibited significant enrichment for Zn and Pb. Multivariate analyses suggested a geogenic source for the PTEs, with some contribution from anthropogenic factors for As, Zn, and Pb. The average hazard index values ranged from 0.000293 (Zn) to 0.030561 (Fe) for adults and from 0.002726541 (Zn) to 0.284670158 (Fe) for children, indicating no significant non-carcinogenic risk to the population in the study area. Additionally, the Lifetime Cancer Risk values for adults and children ranged from 6.94 × 10−6 to 6.46 × 10−5 for As and from 7.13 × 10−8 to 6.65 × 10−7 for Pb, suggesting acceptable or tolerable carcinogenic risk and no significant health hazards.

Influence of the use of remediated soil and agricultural drainage water on the safety of tomato fruits

The objective of this study is to assess the effectiveness of different techniques employed in remediating contaminated soil and wastewater ecosystems to ensure the safety of tomato fruits (Solanum lycopersicum L. var. cerasiforme) cultivated in these environments. Three biochemical techniques T1–T3, besides two controls CCU and CCT, were used to remediate contaminated soil ecosystems using rock phosphate, elemental sulfur, bentonite, phosphate-dissolving bacteria, and Thiobacillus sp. The contaminated agricultural drainage water was remediated by a down-flow hanging sponge (DHS) system. Two experiments were conducted: a pot experiment took place in the greenhouse at the National Research Center of Cairo (Egypt) and a field experiment was carried out at the basin site in the village of El-Rahawy, applying the optimal treatment(s) identified from the greenhouse experiment. The health risk assessment for potentially toxic elements (PTEs) in the harvested tomato fruits was conducted by calculating estimated daily intake (EDI) and target risk quotient (THQ) values. Results from the greenhouse experiment indicated the high effectiveness of the DHS technique in remediating El-Rahawy agricultural drainage water. The content of PTEs after remediation was significantly reduced by 100%, 93.3%, 97.8, and 77.8% for cadmium, copper, manganese, and zinc, respectively. The application of treated drainage water in employed reclaimed soil ecosystems led to a remarkable decrease in PTE levels, especially under T3 treatment; the reduction reached 89.4%, 89.5%, and 78.4% for nickel, copper, and zinc, respectively. The bioremediation technique also reduced the content of PTEs in tomato fruits harvested from both greenhouse and field experiments; the cadmium content, for example, was below detection limits in all treatments. The T3 treatment applied in the greenhouse experiment caused the highest percentage decrease among the employed PTEs in tomato fruits grown in the greenhouse. The same trend was also reached in the field experiment. Microbiological analyses of tomato fruits revealed that E. coli, Salmonella, or S. aureus bacteria were identified on tomato fruits harvested from either greenhouses or field experiments, showing that the counted total bacteria were higher under the field experiment compared to the greenhouse experiment. The health risk assessment parameter THQ was below 1.0 for all tested metals under all treatments. This means that no potential health risk is expected from consuming tomato products produced under the different employed remediation treatments. In conclusion, the employed bioremediation techniques successfully reduced the PTE content and microbial load in both soil and drainage water ecosystems and in harvested tomato fruits. Henceforth, no health risks are expected from the consumption of this product.

Geochemical, ecological, and health risk assessment of potentially toxic elements (PTEs) in the surrounding soil of a cement plant

Cement plants are the major anthropogenic sources of potentially toxic elements (PTEs), which are generated from the processing of raw materials and combustion of fossil fuels. This study determined the PTE concentration and assessed the geochemical, ecological, and health risks associated with the activities in the Ashaka cement plant, Bajoga, Nigeria. Soil samples were collected between 2019 and 2020, and analyzed by ICP-OES for 20 PTEs. The data obtained were statistically evaluated for descriptive and inferential statistics. The mean concentrations of PTEs were in the declined order of Al > Fe > Mn > Zn > Ti > Ba > Sr > Pb > Cu > V > Cr > Ni > As > Sc > Mo > Hg > Cd > Se > Sb > Co. Multivariate analysis revealed that the main sources of PTEs might be related to anthropogenic activities from the cement plant. The geochemical load index (GLI) values obtained range from unpolluted to moderate. The ecological risk ranged from 4.74 × 10–3 to 8.00 × 100, and the overall risk index indicated low contamination for the investigated elements. The hazard index (HI) was < 1, suggesting non-probable non-carcinogenic effects. However, children were more susceptible to risk than adults, and the cancer risk (CR) values of Cd for children and adults were higher than the threshold level of 1.0 × 10–4, which suggests probable development of cancer risk for residents.

Assessment of carcinogenic and non-carcinogenic risk of exposure to potentially toxic elements in tea infusions: Determination by ICP-OES and multivariate statistical data analysis

BackgroundThe perennial evergreen tea (Camellia sinensis) plant is one of the most popular nonalcoholic drinks in the world. Fertilizers and industrial, agricultural, and municipal activities are the usual drivers of soil contamination, contaminating tea plants with potentially toxic elements (PTEs). These elements might potentially accumulate to larger amounts in the leaves of plants after being taken up from the soil. Thus, frequent monitoring of these elements is critically important. MethodsThe present study intended to determine PTEs (Al, Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd, and Pb) in both tea leaves and infusions using ICP-OES. Various multivariate data analysis methods such as principal component analysis (PCA) and hierarchical cluster analysis (HCA) were employed to elucidate the potential sources of PTEs contamination, whether from anthropogenic activities or natural origins. Additionally, Pearson's correlation coefficient (PCC) was calculated to assess the relationships between the variables under study. ResultsThe mean contents (mg/L) of all studied elements in tea infusions decreased in order Mn (150.59 ± 1.66) > Fe (11.39 ± 0.99) > Zn (6.62 ± 0.89) > Cu (5.86 ± 0.62) > Co (3.25 ± 0.64) > Ni (1.69 ± 0.23) > Pb (1.08 ± 0.16) > Cr (0.57 ± 0.09) > Cd (0.46 ± 0.09) > Al (0.05 ± 0.008), indicating that Mn exhibits the highest abundance. The mean concentration trend in tea leaf samples mirrored that of infusions, albeit with higher concentrations of PTEs in the former. The tolerable dietary intake (TDI) value for Ni and provisional tolerable monthly intake (PTMI) value for Cd surpassed the standards set by the WHO and EFSA. Calculated hazard index (HI < 1) and cumulative cancer risk (CCR) values suggest negligible exposure risk. ConclusionElevated levels of PTEs in commonly consumed tea products concern the public and regulatory agencies.

Comparative analysis of sediment quality indices using different reference values in an environmental protection area in Southeastern Brazil.

Contamination of aquatic ecosystems by potentially toxic elements (PTEs) is a concerning environmental issue, given their persistence, toxicity potential, and ability to accumulate in living organisms. Several studies have been conducted to assess the contamination of aquatic ecosystems by PTEs, using pollution and ecological risk indices that rely on the concentration of these elements in aquatic sediments. However, many of these studies use global reference values for calculating the indices, which can lead to misleading interpretations due to substantial variations in PTEs concentrations influenced by the geological characteristics of each region. Therefore, the use of regional reference values is more appropriate when available. This study aimed to investigate variations in the results of five indices, employing global, regional, and quality reference values, based on sediment samples collected from rivers in the Ipanema National Forest, a protected area in Brazil exposed to various anthropogenic pressures. The results revealed that elements such as Al, Fe, and Mn exceeded the limits allowed by legislation in water samples, while As and Cr surpassed the limits in sediment samples. Comparative analysis highlighted significant discrepancies in the results of the indices when global reference values were used compared to regional and quality reference values, especially for As and Ba. Thus, this study underscores the importance of establishing specific regional values for an accurate assessment of sediment quality and the risks associated with contamination by PTEs in different regions worldwide.