Potentially Toxic Elements Concentrations Research Articles

Spatial distribution of potentially toxic elements in e-waste contaminated site at Akwatia-Line, Kumasi, Ghana

E-waste processing sites abound with potentially toxic elements (PTE) that negatively affect the environment and human health. The study determined the presence of selected PTE (Cu, Zn, Pb, Hg, and Al) and their spatial distribution in an e-waste processing site in a developing country setting. pH, moisture, organic matter/carbon, and particle size were determined in 30 soil samples. The spatial position of each sampling point was picked with a GPS device, and the area was mapped in a GIS environment. The concentrations of PTE were determined with an atomic absorption spectrophotometer. Findings from the study indicate that the soil is polluted with PTE, rich in organic carbon/matter but has low pH. The Geoaccumulation Indices ranged from unpolluted (Al) to strongly/extremely polluted (Cu). Pollution Load Index showed about 77 % of the samples as extremely/heavily polluted, 10 % as heavily polluted, and 13 % as moderately polluted. Contamination Factors of Zn, Pb, and Cu were very high but considerably low for Hg and Al. Regular monitoring and remediation are required for the soil to be restored and put into productive use.

Spatial distribution and source identification of potentially toxic elements in Yellow River Delta soils, China: An interpretable machine-learning approach

Identifying the driving factors and quantifying the sources of potentially toxic elements (PTEs) are essential for protecting the ecological environment of the Yellow River Delta. In this study, data from 201 surface soil samples and 16 environmental variables were collected, and the random forest (RF) and Shapley additive explanations (SHAP) methods were then combined to explore the key factors affecting soil PTEs. An innovative t-distributed random neighbor embedding-RF-SHAP model was then constructed, based on the absolute principal component score and multivariate linear regression model, to quantitatively determine PTE sources. Although average PTE concentrations did not exceed the risk control values, PTE distributions exhibited significant differences. It was found that sodium, soil organic matter, and phosphorus contents were the three most important factors affecting PTEs, and human activities and natural environmental factors both influence PTE contents by altering the soil properties. The proposed model successfully determined PTE sources in the soil, outperforming the original linear regression model with a significantly lower RMSE. Source analysis revealed that the parent material was the main contributor to soil PTEs, accounting for more than half of the total PTE content. Industrial and agricultural activities also contributed to an increase in soil PTEs, with average contributions of 19.91 % and 17.44 %, respectively. Unknown sources accounted for 10.83 % of the total PTE content. Thus, the proposed model provides innovative perspectives on source parsing. These findings provide valuable scientific insights for policymakers seeking to develop effective environmental protection measures and improve the quality of saline-alkali land in the Yellow River Delta.

Assessment of transfer factor of potential toxic elements (PTEs) in aloe vera plant

ABSTRACT Aloe Vera plants are widely used for cosmetic, health and Medicinal purposes. Various studies have highlighted the nutritional and health benefits of Aloe Vera plants, but few studies have investigated their bioconcentration of pollutants. The main aim of our study was to estimate transfer factor (TF) of potential toxic elements (PTEs) in aloe vera gel. We estimated of PTEs including arsenic (As), cadmium (Cd), iron (Fe), nickel (Ni), lead (Pb), and zinc (Zn), in 5 groups of aloe vera plants. After 6 weeks we sampled the aloe vera gel and soil and detected the concentration of PTEs using inductively coupled plasma optical emission spectrometry (ICP-OES). We then estimated the concentration of PTEs in aloe vera gel in Iran using the results of a meta-analysis of PTEs in agricultural soil in Iran and a Monte Carlo Simulation (MCS) model. The mean (± SD) TF for Fe, Pb, As, Cd, Zn, and Ni were equal to 0.558 ± 2.487%, 0.555 ± 1.225%, 0.163 ± 0.372%, 0.122 ± 1.123%, 0.069 ± 0.415% and 0.032 ± 0.748%, respectively. The rank order of PTEs, based on their TF, was Fe > Pb > As > Cd > Zn > Ni. Moreover, the rank order of PTEs, based on the 95th percentile of concentrations in Aloe vera gel in Iran, was Pb (0.7828 mg/kg) > As (0.2800 mg/kg) > Zn (0.1601 mg/kg) > Cd (0.0444 mg/kg). TF of PTEs in Aloe vera gel were less than 1, which shows natural levels of metals in plant tissues. On the other hand, the 95th percentile concentration of PTEs in aloe vera gel was lower than the standard limits. Hence, aloe vera gel cannot threaten the health of consumers due to PTEs.

Health risk assessment and quality reference values of potentially toxic elements in soils of the Southwestern Amazonas State – Brazil

The geochemical processes involved in the Amazon soils formation are not totally understood because its geological and pedological features were formed during different geological events and different times. The Southwestern region of Amazonas State is an example of a region where the soils were developed from rocks formed by sedimentary processes and, nowadays, the soils continue receiving seasonal inputs from the Andes sediments. Data on geochemical patterns of this region are scarce, and there is no information about the possible effects of the natural or unnatural enrichment of potentially toxic elements (PTEs). Thus, this study represents the first research into the geochemical patterns of PTEs in soils of Southwestern Amazonas State. Further, we carried out a human health risk assessment and a proposal for Quality Reference Values (QRV) for thirteen PTEs (As, Ba, Cd, Co, Cr, Cu, Mn, Ni, Pb, Ti, V, Zn and Zr). Our findings showed that the PTEs contents in soil samples collected in the lowland areas are strongly influenced by sediments inputs, while samples localized in the highland areas are weakly influenced by sediments inputs and present depletion of PTEs. Barium, Cr, Cu, Ni and Pb were the PTEs most influenced by sediment's deposition. The soil contamination assessment showed the existence of enrichment of the potentially toxic elements in soil samples, which may be a consequence of the natural inputs of the Andean sediments. Furthermore, Co and Cr exceed the safety zone for carcinogenic risk assessment, which indicates the need to monitor these elements and their possible effects on the health of the population in this region.

Potentially toxic elements and lead isotopic signatures in the 10 μm fraction of urban dust: Environmental risk enhanced by resuspension of contaminated soils

In urban environments, soils are a sink of pollutants and might become a source of contamination, as they commonly display potentially toxic elements (PTE) concentrations above the legislative limits. Particularly, the inhalable fraction of soils (<10 μm) is enriched in PTE compared to bulk soils (BS). The enrichment makes these particles an environmental hazard because of their susceptibility to resuspension and their potential contribution to road dust (RD) and atmospheric particulate matter (PM10) pollution.To gain a better insight into urban contamination dynamics we studied the BS, the resuspended <10 μm fraction of BS (Res-BS) and RD (Res-RD) in a European historically industrialized and densely populated city. Compared to BS, the Res-BS and Res-RD showed higher PTE concentrations and a higher variability for most of the elements. Lead was the only PTE showing similar concentrations in all the matrices, suggesting shared sources and redistribution pathways within the city. Chemometric elaborations identified Res-BS as a transition between BS and Res-RD or, rather, a Res-RD precursor. Also, Pb was confirmed to be ubiquitous in all the media.In all the matrices, Pb isotopic signatures were investigated and compared with PM10 fingerprints from the same city. The anthropogenic isotopic signature in Res-BS and Res-RD was evident, and samples belonging to neighboring sites showed comparable isotopic ratios. The Res-BS appeared as a key driver for Pb distribution within the city both in Res-RD and in PM10. These results demonstrate the intimate interaction between urban environmental compartments (soil, road dust and PM10), and the active contribution of fine soil fractions to anthropogenic pollution, with relevant policy implications in urban areas since soils were found to contribute directly to air pollution.

Potentially toxic elements in rainwater during extreme rainfall period in the megacity Beijing: Variations, sources, and reuse potential

Air pollution has become a worldwide problem, which resulted in various environmental threats to the human beings and surface ecosystem. It is thus significant to clarify the sink/source process of atmospheric contaminants, such as the potentially toxic elements (PTEs). The rainfall process is a vital sink for atmospheric PTEs, which can effectively reduce their content in atmosphere. However, the understanding blind spot of variations, sources, and reuse potential of rainwater PTEs in megacities (hotspots area of atmospheric PTEs deposition) still existed, particularly in extreme rainfall period. For this, the daily-scale rainwater samples were collected in Beijing City during extreme rainfall period, and the selected PTEs were measured and further analyzed. The results indicated a volume-weighted mean PTEs concentration (in μg/L) order of Zn (10.86) > Mn (3.21) > Fe (0.73) > Cu (0.69) > Ni (0.35) > V (0.22) > Cr (0.09) ≈ Pb (0.09) > Cd (0.04). Zn was the most abundant PTEs, which was 2∼3 magnitude orders greater than the low abundant PTEs, such as Cr, Pb, and Cd. The sources of PTEs and the dissolved processes of atmospheric components (e.g., particulate matter) were the predominant influencing factors of rainwater PTEs variations, and the rainfall amount was also the potential (not the critical) influencing factor, while the influence of rainwater pH is negligible. According to the enrichment factor and multivariate statistical analysis, the Cd, Zn, and Cu were primarily attributed to anthropogenic sources, which were typically derived from fossil fuel burning, vehicle emission, and domestic waste combustion. The crust sources mainly contributed the Fe, Cr, and V, while the other PTEs (Mn, Ni, and Pb) were derived from a combination of human and natural inputs. Reuse potential assessment revealed that the harvested rainwater was suitable for irrigation of urban green space and vegetation (low soil hazard), and may potentially be utilized for drinking purpose under extreme conditions (after addressing the problem of ammonia nitrogen). This work identified the PTEs characteristics in urban wet deposition, which will help knowledge of PTEs biogeochemical cycle and sustainable use of rainwater resources under climate and environmental change.

Effects of dissolved organic carbon on potentially toxic element desorption in stormwater bioretention systems

Stormwater runoff contains dissolved organic carbon (DOC) and potentially toxic elements (PTEs). Interactions between DOC and PTEs can impact PTE speciation and mobility, but are not fully understood. Soil samples were collected from a vegetated bioretention bed to investigate the effects of DOC (0, 15, and 50 mg-C/L) on the desorption of 10 PTEs captured by the soil media: Mn, Fe, Co, Cu, Zn, As, Cd, Sn, Sb, and Pb. In the absence of DOC, the desorbed PTE concentration from bioretention media into the aqueous phase ranking was as follows: Fe > Mn ∼ Zn > Cu > Pb > Sb > As > Co > Sn ∼ Cd. Increased DOC concentrations resulted in a reduction of the soil-water distribution coefficient (Kd) values. The greatest shift in Kd was observed for Cu and lowest for Sb. The PTE sorption capacities were lower for surficial soil samples (lower Kd) compared to the deep soil samples. Overall, the desorbed PTE (average midchannel 55.7 μg/g) fraction accounted for <1.1 % of the total extracted PTEs (5364 μg/g), and while this is a small percentage of the total, this is the fraction that is mobile. The extracted PTE fractions revealed that DOC reduced the organic matter-bound and carbonate-bound fractions. The PTE desorption trends suggest that reducing DOC in stormwater runoff could be an effective measure to mitigate the release of PTEs into the environment.

Robinia pseudoacacia L. (Black Locust) Leaflets as Biomonitors of Airborne Microplastics.

Here we investigate the suitability of Robinia pseudoacacia L. (black locust) leaflets as a novel biomonitor of airborne microplastics (MPs) including tyre wear particles (TWPs). Leaflets were collected from rural roadside locations (ROs, n = 5) and urban parks (UPs, n = 5) in Siena, Italy. MPs were removed by washing, identified by stereomicroscope, and analysed for polymer type by Fourier transform infrared spectroscopy. Daily MP deposition was estimated from leaf area. The mass magnetic susceptibility and the bioaccumulation of traffic-related potentially toxic elements (PTEs) were also analysed. The total number of MPs at ROs was significantly higher at 2962, dominated by TWPs, compared with 193 in UPs, where TWPs were not found. In contrast, total microfibres were significantly higher in UPs compared with ROs (185 vs. 86). Daily MP deposition was estimated to range from 4.2 to 5.1 MPs/m2/d across UPs and 29.9-457.6 MPs/m2/d across ROs. The polymer types at ROs were dominated by rubber (80%) from TWPs, followed by 15% polyamide (PA) and 5% polysulfone (PES), while in UPs the proportion of PES (44%) was higher than PA (22%) and polyacrylonitrile (11%). The mean mass magnetic susceptibility, a proxy of the bioaccumulation of traffic-related metallic particles, was higher at ROs (0.62 ± 0.01 10-8 m3/kg) than at UPs (-0.50 ± 0.03 10-8 m3/kg). The content of PTEs was similar across sites, except for significantly higher concentrations of Sb, a tracer of vehicle brake wear, at ROs (0.308 ± 0.008 µg/g) compared with UPs (0.054 ± 0.006 µg/g). Our results suggest that the waxy leaflets and easy determination of surface area make Robinia an effective biomonitor for airborne MPs including TWPs.

Impact of cement industries on potentially toxic elements’ contamination and other characteristics of topsoil: A case study

ABSTRACT Due to the elevated levels of potentially toxic elements (PTEs) in the environment, we measured the PTE concentration in topsoils at a distance of 500, 1000, and 2000 m from 3 cement production factories (1 = DG Cement, 2 = Bestway Cement, Kallar Kahar, and 3 = Bestway Cement, Chakwal) toward east, west, north, and south direction. Soil samples were collected and analyzed for cadmium (Cd), chromium (Cr), copper (Cu), iron (Fe), lead (Pb), manganese (Mn), nickel (Ni), zinc (Zn), and cobalt (Co) concentrations. It was recorded that the maximum PTE concentrations were found at 500 m distance and in north direction in 93% of the samples. The maximum Cd, Cr, Fe, Mn, Ni, Zn and Co concentrations were found around Bestway Cement, Chakwal at 4.13, 27.82, 6552.20, 93.47, 99.54, 46.83, and 72.62 mg kg−1, respectively. Similar results were found for the other two industries at same distance and direction. It was also revealed that contamination factor and geo-accumulation index were exceeding in the 84% and 81% of the total samples collected. The findings of the study indicate that there could be toxicity in soil and food crop in vicinity of the area, which should be studied.

Soil enrichment of potentially toxic elements in relation to land‐use types in an alpine meadow of the Qinghai–Tibet Plateau

AbstractThe Qinghai–Tibet Plateau, a fragile ecosystem with unique biodiversity, is particularly susceptible to soil contamination from increasing anthropogenic activities like grazing and farming. However, research exploring the relationship between these factors remains limited. Our study examines soil changes and potentially toxic elements (PTEs) after converting alpine meadows, providing insight into the impact of land‐use in this area. We found significant differences in the concentrations of PTEs (Cd, Cr, Hg, and Pb) among the three land‐use types. Soil from Oat Field (OF) had lower levels of Cd, Cr, Hg, and Pb compared with Fence Enclosure (FE) and Winter Grazing (WG), indicating a potential uptake/phytoextraction of these elements by oats. Different profiles of soil physiochemical properties were also detected, particularly in the OF soil, which showed significantly lower available potassium, microbial carbon, and microbial nitrogen but higher soil bulk density and total and available phosphorus. Additionally, significant stratification was observed in soil concentrations of most studied PTEs and nutrients in FE and WG, but not in OF. Specifically, lower levels of As, Cr, and most nutrients were found in the top layer (0–10 cm) compared with the bottom layer (20–30 cm). By comparison, Cd and Hg showed higher concentrations in the top layer in FE. These contrasting trends suggest potential differences in the mobility or bioavailability of these elements in the soil of the alpine meadow. Furthermore, significantly negative correlations were found between most soil nutrients, and the concentrations of As, Cr, and Pb, whereas significantly positive associations were observed for soil nutrients with Cd and Hg. However, such relationships predominantly existed in soils of WG and FE, but not OF. Collectively, our results suggest the potentially disrupted PTE accumulation and nutrient distribution by anthropogenic activities, particularly agricultural practices within the studied land‐use types, and warrant further evaluation of the associated ecotoxicological risks.

Characterization of flue gas desulphurized (FGD) gypsum of a coal-fired plant and its relevant risk of associated potential toxic elements in sodic soil reclamation.

Thermal Power Plant generates FGD gypsum as by-product during coal combustion. This study evaluates the characterization (spectroscopic and elemental), potentially toxic elements (PTEs) distribution, and environmental risk assessment of FGD gypsum for safe and sustainable use in agriculture. The XRD and SEM analysis confirmed the dominance of crystalline CaSO4·2H2O in FGD gypsum. The order of concentrations of PTEs in FGD gypsum was Fe > Al > Mn > Zn > Ni > Co. The residual fraction was the dominant pool, sharing 80-90% of the total PTEs. The heavy metals (HMs) were below the toxic range in the leachates. The Co, Ni, Al, Fe Mn, Zn had low (< 10%) risk assessment code and the ecotoxicity was in the range of 0.0-7.46%. The contamination factor was also low (0.0-0.16) at the normal recommended doses of FGD gypsum application for sodicity reclamation. The enrichment factor was in the order of Al < Mn < Co < Zn < Ni. Mn [enrichment factor (Ef) 1.2-2.0] and Co (Ef 1.7-2.8) showed negligible enrichment of metals, whereas Ni (Ef 4.3-5.2) and Zn (Ef 4.5-5.6) reported moderate accumulation in soil. The application of FGD gypsum @ 10 t ha-1 for sodicity reclamation will develop a geo-accumulation index below the critical values indicating its safe and sustainable use to achieve land degradation neutrality (LDN) and UN's Sustainable Development Goals.

Metal and metalloid concentrations in wild mammals from SW Europe: European hedgehog (Erinaceus europaeus) and badger (Meles meles)

In recent years, there have been increasing ecological and global concerns associated to Potentially Toxic Elements (PTEs). Thus, the relevance of wild mammals as biomonitors has been globally recognised. In the present study, Cd, Pb, Hg, Zn and As concentrations were quantified in European hedgehog and badger inhabiting SW Europe, and cumulative trends in relation to age and sex were evaluated. Liver and kidney samples were collected, mineralised and PTE content was determined by ICP-MS. Zn was the most abundant element quantified in both organs (239 and 89.8 mg kg-1 for hedgehogs and 179 and 164 mg kg-1 dw for badgers). In hedgehogs, very high Hg concentration were quantified (4.35 and 15.5 mg kg-1 dw in liver and kidney), and Cd was the most abundant for badgers (4.70 and 7.61 mg kg-1 dw in liver and kidney). Positive correlations were observed for the concentrations of PTE in the organs of both species. Age-dependence increased only Cd concentration, with levels in adult kidneys being significantly higher. In this study, European hedgehog and badger were used as biomonitors for the determination of PTEs to provide current reference values in relatively non-polluted areas of SW Europe, and to enhance the use of these species for future ecotoxicological studies.Graphical

Human health risk assessment of potentially toxic elements and microplastics accumulation in products from the Danube River Basin fish market

The present study aimed to quantify the concentration levels of potentially toxic elements (PTEs) such as aluminum, arsenic, cadmium, chromium, copper, nickel, lead, zinc, and mercury, as well as microplastics occurrence in various tissues of fish and seafood species, commercialized in the Lower Danube River Basin. A health risk assessment analysis was performed based on the PTEs concentration levels in the muscle tissue. Estimated daily intake (EDI), target hazard quotient (THQ), hazard index (HI), and target cancer risk (TR) of PTEs were calculated. It was observed that the species within the seafood category registered the highest levels of PTEs. For instance, in the muscle tissue of bivalve Mytilus galloprovincialis (from the Black Sea), the highest value was observed in the case of Zn (37.693 mg/kg), and the presence of polystyrene polymer was identified. The values associated with EDI, THQ, HI, and TR of PTE exposure were significantly lower than 1.

Biomonitoring of Potentially Toxic Elements in an Abandoned Mining Region Using Taraxacum officinale: A Case Study on the “Tsar Asen” Mine in Bulgaria

Mining is a significant industrial and economic activity, but it can also result in ore waste that contains several potentially toxic elements (PTEs). Furthermore, the wide range of observed transfer and accumulation factors suggests that not only the soil element concentrations but also the soil characteristics are important for uptake, which is recognized as a serious problem with potential impacts on human health and ecosystems. The aim of this study was to perform a pollution risk assessment of a region near an abandoned mine using suitable biomonitoring followed by multivariate statistical treatment of the obtained results. The content of PTEs in the soil and plant samples was determined to exceed the background concentrations typical for Bulgaria. The observed concentrations of copper in this study’s soil samples exceeded 2 to 16 times the maximum permissible values. The Taraxacum officinale concentrations for PTEs, particularly for Cd (5.13 mg/kg), were higher than the background levels. The obtained results for PTEs show significant TFs for Cd and Sn, while the AFs outline a significant accumulation of Cd and Sb. The applied multivariate statistical approaches revealed differences between the sampling locations and relationships between the elemental transfer/accumulation factors and soil cation exchange capacity. The outcomes from the statistical analysis confirm that the usage of both element factors and soil properties in biomonitoring studies are essential for reliable risk assessment.

Background and geochemical baseline values of chalcophile and siderophile elements in soils around the former mining area of Abbadia San Salvatore (Mt. Amiata, southern Tuscany, Italy)

Background and geochemical baseline values of Potentially Toxic Elements (PTEs) in soils developed on natural or anthropogenically-affected areas are increasingly important parameters as they represent highly useful tools at local, regional, national and European level. While background values are mostly applied to uncontaminated areas to verify the presence of high to anomalous concentrations of PTEs due to geogenic sources, the geochemical baseline values are better representing those areas where the anthropogenic activities have altered more or less significantly the background values. This is the case of the Municipality of Abbadia San Salvatore, mostly lying above the volcanic products of Mt. Amiata (Tuscany, central Italy) and, subordinately, above sedimentary formations, where >100 years of exploitation of cinnabar (HgS) and production of liquid mercury have affected the environmental matrices, including the pedosphere compartment. Consequently, 51 top-soils and 51 sub-soils, developed on the volcanic and sedimentary domains were collected and analyzed for PTEs (Hg, As, Sb, Cr, Co, Ni, Cu and V). A CoDA (Compositional Data Analysis) approach (robust Principal Component Analysis) combined with geochemical mapping allowed to account for the compositional nature of geochemical data and define the spatial distribution of the investigated chalcophile and siderophile elements. The results obtained by CoDa are useful to understand data variability and relative variations of the elements compared to the barycenter of the total composition. Independently by the substratum (volcanic or sedimentary), the concentrations of Hg, As, Sb, Cr, Co, Ni, Cu and V were highly variable and up to 258, 276, 110, 261, 32, 132, 80 and 173 mg/kg, respectively. Owing to the significant differences between the two geological domains, the two datasets were considered separately in order to define the geochemical baseline values of the analyzed PTEs computed using ProUCL 5.2.0 software. Accordingly, the geochemical baseline values of Hg, As, Cr, Co and V were much higher than the values imposed by the Italian Legislative Decree 152/06, suggesting the importance of exploring the geological features of the investigated territories and their anthropic history, particularly in Italy where poly-metallic sulfide ore deposits have been exploited in many regions since the Etruscan and Roman times.

Terrestrial inputs and physical processes control the distributions of potentially toxic elements (PTEs) in the seawater of the large-range Beibu Gulf, the northern South China Sea

The potentially toxic elements (PTEs), Cu, Pb, Zn, Cd, Cr, Hg and As in the water from the Beibu Gulf, were investigated to reveal the contaminant characteristics and assess the risks to human health. The results showed that the concentration of PTEs in the Beibu Gulf varies significantly both seasonally and spatially, with higher concentrations in summer and in the northern and southern gulf. Terrestrial inputs and local anthropogenic discharge are responsible for the higher level in the northern gulf, and the transportation of water masses is also an important factor for the higher concentrations in the southern gulf. Ecological risk assessment suggested that Hg is the main ecological risk factor. The health risk assessment revealed that dermal exposure to PTEs in the gulf presents potentially carcinogenic health effects for humans. This study provides new insight into the transport of PTEs over a large area of the Beibu Gulf.

Cadmium, chromium, nickel and lead content of fish and vegetables from selected dams in Osun State, Nigeria

Potentially Toxic Elements (PTEs) in foods are a threat to global health. This study investigated concentrations of selected PTEs; cadmium, chromium, nickel and lead in fish and cultivated vegetables from and along the dams, respectively. Totally, 84 samples; 60 Tilapia (Oreochromis niloticus), 12 Okra (Abelmoschus esculentus) and 12 Bitter leaf (Vernonia amygdalina) obtained from six dams in Southwestern Nigeria were digested using aqua-regia. Elemental quantification with Flame Atomic Absorption Spectrophotometer and validation via recovery test (97.1–100%), linearity (R2 ≥ 0.997) and limit of detection (LOD) (0.01–0.18 mg kg-1) were done. The PTEs concentrations in the two vegetables did not maximum exceed the permissible levels, except for Pb. In fish samples, PTEs concentrations were > maximum permissible levels and ranged from 1.18 to 2.31, 3.15–3.92, 0.41–14.2 and 2.36–3.73 mg kg-1 for Cr, Ni, Cd and Pb respectively. Human health risk assessment revealed the Estimated Daily Intake (EDI) values for consumption of Tilapia by children for Pb and Cd were > Tolerable Daily Intake (TDI) while for adults, higher EDI values were for Pb. Conclusively, non-carcinogenic and carcinogenic assessment results reveal that consumption of tilapia, okra and bitter leaf from these dams is not safe.

Risk assessment of potentially toxic elements in agricultural soils and bioconcentration in rice grains from Faridkot District, India

Potentially toxic elements (PTEs) in soil pose significant risks to both ecology and human health. Therefore, to understand the effect of PTEs in agricultural soils of Faridkot District, Punjab, India, 36 soil samples were analyzed for physicochemical properties, contents of PTEs (aluminum, arsenic, nickel, boron, uranium, barium, chromium, cadmium, copper, iron, lead, cobalt, manganese, selenium, and zinc), possible ecological and human health risks and bioconcentration in rice grains. Soils showed high mean contents (mg/kg) of potassium (906.65), sodium (760.78), and chlorides (247.13) with cadmium, copper, zinc, arsenic, and selenium contents (mg/kg) in 55.56%, 33.33%, 25.00%, 16.67%, and 13.89% of samples exceeding their safe limits (0.06, 20.00, 50.00, 20.00, and 0.20, respectively). Individual and multi-element indices suggested extremely high-soil enrichment of arsenic, cadmium, and selenium and low to moderate ecological risk. Multivariate analyses revealed the contribution of both geogenic and anthropogenic activities to soil contamination. Mean bioconcentration factors of chromium (4.48), boron (1.24), and copper (2.69) were >1.00 in rice. Residents had higher cancer risk (TCR) due to arsenic (3.64E-05) and chromium (4.04E-06) in soil, mainly through ingestion and dermal contact. This work could serve as baseline database for further research and designing the strategy to alleviate soil contamination.

Potential Toxic-Element Pollution in Surface Water and Its Implications for Aquatic and Human Health: Source–Pathway–Receptor Model

This study focused on assessing the extent of pollution in both flowing and non-flowing surface water within the Matjhabeng mining area of South Africa, with particular emphasis on the substantial impact of gold mine tailings. A comprehensive analysis of physical water-quality attributes, including potentially toxic elements (PTEs), and relevant pollution risk indices was undertaken. To comprehensively elucidate the potential risks to aquatic organisms and human health, a risk assessment framework predicated upon the source–pathway–receptor model was developed. Principal Component Analysis (PCA) was employed as a multivariate statistical tool to discern the potential origins of PTE contamination within the environment. The results substantiate pronounced pollution manifestations within the surface water milieu of the Matjhabeng mining area. Specifically, concentrations of critical PTEs, such as arsenic, cobalt, copper, iron, selenium, and zinc, exhibited transgressions of the regulatory thresholds stipulated by both the South African Department of Water Affairs and Forestry (DWAF) and the Canadian Council of the Ministers of the Environment (CCME). Additionally, concentrations of the aforementioned elements exceeded the stipulated DWAF guidelines for irrigation water usage. Pollution indices, encompassing the Single-Factor Pollution Index and the Nemerow Integrated Pollution Index, discerned moderate contamination stemming from As, while remarkably elevated pollution levels were identified for selenium. PCA elucidated 94.5% of the aggregate variance, revealing cobalt, copper, nickel, and zinc as coalescing within PC1, indicative of a common anthropogenic provenance that is conceivably linked to historical gold mine tailings. PC2 exhibited an aggregation of chromium, iron, and lead, reaffirming this shared anthropogenic etiology. The third PCA component was characterized by selenium, followed by arsenic and magnesium in the fourth. The resultant PTE contamination underscores a profound ecological and public health risk, impacting both the aquatic ecosystems and the local community within the precincts of the Matjhabeng Local Municipality (MLM) area, with consequential amplification of susceptibilities to deleterious health consequences. Urgent and concerted interventions are imperative to ameliorate the emergent decline in surface-water quality within the MLM locale. The adoption of nature-based remediation paradigms holds promise for efficaciously elevating water quality, ameliorating community health, and underpinning the long-term economic viability of the region.

The evaluation of potentially toxic elements using artificial neural networks and fuzzy linear regression analysis methods in cappadocian volcanic ash soils of Turkey

The aim of this study is to determine the relationships between some potentially toxic elements (PTE) (Cu, Mn, Ni, Zn) in human stomach and intestinal tissues and toxic element contents in soil, vegetables and fruits. This study was conducted in the eastern of Erciyes Strato volcano, an area of 2400 km2 in Turkey. Tissue samples taken from the stomach and intestines of people living in the study area, soils, vegetables, and fruits were used as material. In the study, tissue samples of 26 people's stomach and intestines, 576 soil samples from 192 points and 3 different depths (0–30 cm, 30–60 cm, and 60–90 cm) and vegetable and fruit samples from 137 sampling points were taken. Cu, Mn, Ni, and Zn contents of human tissue samples, soil samples, vegetable and fruit samples were determined. Artificial Neural Networks method (ANN) and Fuzzy Linear Regression Analysis (FLRA) methods were used to determine the relationships between PTE contents in human tissue samples and soils, vegetables, and fruits. Root Mean squared error (RMSE) and coefficient of determination (R2) indices were used as the test criteria for goodness of fit. When compared with ANN method, it was determined that PTE values in stomach and intestinal tissue estimated by FLRA method had the lowest error and high R2 values. It was found that the most effective variable in estimating the average PTE value in stomach and intestinal tissue is PTE values in soil. It was determined that the FLRA regression analysis method has a better predictive power than the ANN method. Using FLRA and ANN regression methods, it was determined that there is a statistically high relationship between PTE contents in soils and stomach and intestinal tissues. It is recommended to make the study findings more meaningful with effective and reliable service planning by using different regression analysis methods in ecological and clinical studies.