Potentially Toxic Elements Concentrations Research Articles

Health and Ecological Risk From Potentially Toxic Elements in Soils and Extra Virgin Olive Oils From Valdichiana Senese, Tuscany (Italy)

ABSTRACTBackgroundExtra virgin olive oils (EVOOs) are widely consumed but rarely analysed for potentially toxic elements (PTEs), whose concentrations in EVOOs can be significantly influenced by contamination in olive grove soils. As food consumption is the main PTE accumulation pathway in humans, thorough investigation on EVOOs is necessary.AimThe concentrations of 12 PTEs were determined in olive grove soils and EVOOs from Valdichiana Senese (Southern Tuscany, Italy), with the aim of identifying any contamination by PTEs in olive grove soils and evaluating the associated ecological risk as well as of assessing the potential risk for human health related to PTE intake from EVOO consumption.MethodsThe soil and EVOO samples were collected from 18 farms, and the concentration of As, Cd, Co, Cr, Cu, Ni, Pb, Sb, Tl, U, V and Zn was determined by inductively coupled plasma mass spectrometry (ICP–MS). The data were used to calculate the health risk index (HRI) for EVOOs and the geoaccumulation index (Igeo) and potential ecological risk index (PERI) for soils.ResultsAnalytical data suggested that the PTE concentrations in the investigated olive grove soils are natural as comparable to their normal geochemical background in soils from Southern Tuscany formed from the same parent rocks of Valdichiana Senese soils or due to local geogenic enrichments in some parent rocks. Among the analysed PTEs in the EVOO samples, Zn, Cu and Ni had the highest concentrations, followed by Cr and Pb. Most PTEs showed a high variability of their concentrations in EVOOs from Valdichiana Senese.ConclusionOn the basis of values of indices applied to PTE concentrations in the soil samples, a low‐to‐moderate Cu contamination emerged only in the olive grove soils of two farms, probably as a consequence of the diffuse use of Cu‐based products in agriculture, and overall, the ecological risk was low. Furthermore, although EVOOs from Valdichiana Senese have somewhat slightly high concentrations of some PTEs such as Cu and Zn, the health risk associated with their intake through the EVOO consumption is definitely negligible.

Potentially toxic elements (PTEs) in seabirds foraging across a heterogeneous landscape: Cross-species bioaccumulation patterns.

Seabirds are particularly susceptible to potentially toxic elements (PTEs) due to the tendency of biomagnification of some elements, thus serving as potential bioindicators for assessing environmental health. In this study, we analyzed As, Cd, Cu and Zn concentrations in liver samples from nine seabird species (51 specimens) collected along the Southwestern Atlantic Ocean. Results revealed substantial variations in PTE concentrations among species, with taxonomic orders influencing accumulation patterns. The observed PTE concentrations in seabirds suggest potential trends in bioaccumulation, influenced by species-specific behaviors and diets. For instance, As ranged from 0.47mgkg-1 in Nannopterum brasilianus to 70.25mgkg-1 in Thalassarche melanophris, while Cd ranged from 0.01mgkg-1 in N. brasilianus to 232.73mgkg-1 in Spheniscus magellanicus. Generalized Linear Model (GLM) results identified body length and species as the main factors influencing PTE concentrations for most elements. Spearman correlation analysis revealed a strong positive correlation between Cd and Cu (ρ=0.68), Cd and Zn (ρ=0.67) and between Zn and Cu (ρ=0.56), suggesting that seabirds with higher Cd levels also tend to have higher Cu and Zn concentrations. Multivariate statistical analysis demonstrated distinct PTE compositions among bird groups. Although significant variations in total concentrations of elements like Zn and Cu were observed among species, the relative contributions of each element to the overall load in the organism showed a convergence in proportions. This underscores the need for further research on homeostatic processes and the potential impacts of environmental PTEs on seabird health.

Elucidating the hydrochemistry and REE evolution of surface water and groundwater affected by acid mine drainage.

The impact of pyrite mining on water quality is a global concern. This study investigates the impact of acid mine drainage (AMD) from an abandoned pyrite mine in the Qinling Mountains on surface and groundwater hydrochemistry and rare earth elements (REEs) evolution. A total of 54 water samples were collected in 2021, of which the Muzi River downstream of the mining area was repeated three times in three sampling periods. Hydrogeochemical methods and stable isotope techniques were used to analyze the impacts of AMD. Results showed that tailing water in comparison to groundwater and surface waters exhibits low pH with high concentrations of SO42-, potentially toxic elements (PTEs), and REEs, and is characterized by normalized middle REE (MREE) enrichment. Groundwater is less influenced by AMD and shows HCO3-Ca and HCO3-Ca·Na types. AMD contaminates surface water to different degrees. Surface water received SO42- input from AMD, exhibited SO4-Ca, SO4·HCO3-Ca, and HCO3·SO4-Ca types within the mining area, and evolved from HCO3·SO4-Ca to HCO3-Ca downstream as AMD influence diminishes. High concentrations of PTEs and REEs are presented in AMD and seepage near the slag heap, and decreased rapidly along the flow path, while SO42- migrated over longer distances. The water in the study area primarily originates from atmospheric precipitation, with close relation among surface water, groundwater, and tailing water. Water-rock interactions and pyrite oxidation governed the hydrochemical composition, with sulfide oxidation facilitated the carbonatite-water reaction, which alleviated sulfide oxidation-induced acidification. The concentrations of PTEs are regulated by adsorption and precipitation, carbonate buffering, and dilution along the flow path. REEs are mainly controlled by pH, inorganic complexation, and secondary mineral adsorption. As the pH changes from acidic to neutral or weakly alkaline, REEs shift from sulfate-complex dominated to carbonate-complex dominated. These insights contribute to a better understanding of AMD impacts on surface and groundwater, providing a basis for the rational management of AMD.

Mapping Soil Contamination in Arid Regions: A GIS and Multivariate Analysis Approach

Heavy metal soil contamination is a global environmental issue that poses serious threats to human health, agricultural advancement, and ecosystem systems. Thirty-five soil samples from various parts of Jazan, Southwest Saudi Arabia, were collected. To create spatial pattern maps for nine potentially toxic elements (PTEs) (As, Co, Cr, Cu, Fe, Ni, Pb, V, and Zn), Ordinary Kriging (OK) was utilized. The variability of the soil metal concentration was estimated using multivariate analysis, including principal component analysis (PCA) and cluster analysis. In addition, the levels of soil contamination in the research area were assessed using contaminations indices, namely, Enrichment Factor (EF), Contamination Factor (CF), and geoaccumulation index (Igeo), and modified contamination degree (mCd). Normalized Difference Vegetation Index (NDVI) and land use/land cover (LULC) were assessed to evaluate vegetation density and identify different forms of land cover and land use. The results showed that the Gaussian model fitted As well, whereas the spherical model fitted Co, Cr, Cu, Ni, and Zn. An exponential model was fitted to Fe and V. Pb also suited the Stable model. In each of the selected metals, the root mean square standardized error (RMSSE) values were close to one, and the mean standardized error (MSE) values were almost zero for each fitted model. Moreover, the findings showed that there was a tendency for the concentration of heavy metals in the research area to rise from west to east. The cluster analysis divided the data in this investigation into two clusters. Significant alterations in Co, Cr, Cu, Fe, Ni, V, and Zn were revealed by the acquired data. However, the total As and Pb concentrations in the two clusters did not differ significantly. The mCd value of the research region often fell into one of three classes, with areas of 148.20 km2 (nil to very low degree of contamination), 26.16 km2 (low degree of contamination), and 0.495 km2 (moderate degree of contamination). The findings indicated that the minerals connected to the Arabian Shield’s basement rocks are the main source of these PTEs. It is crucial to monitor PTEs contamination because the research region is highly cultivated, as shown by the NDVI and LULC status. Given the potential for future pollution due to human activity, PTEsPTEs decision-makers may use the findings of the spatial distribution maps of pollutants and their concentrations as a basis for future monitoring of PTEs concentrations in the study area.

Removal of Zn(II), Cu(II) and Pb(II) from Rainwater by White Bean Peel: Optimization by Response Surface Methodology

Potentially toxic elements (PTEs) have been found in high levels in rainwater, highlighting the importance of removing them when the water is intended for domestic use. In this work, white bean peel was evaluated as sorbent for the removal of a mixture of PTEs from rainwater, namely Zn(II), Cu(II) and Pb(II). A uniform experimental design was used to evaluate the sorption and to optimize the removal process by response surface methodology. The biosorbent reduced the PTEs concentration in the solution, and their removal increased with the increase of the initial concentration and with time. The removal of Cu(II) and Pb(II) was affected by the pH of the solution since, at pH 7.0 for Cu(II), and at pH 5.6 and 7.0 for Pb(II), a decrease occurred in the removal. The optimal conditions for removal, 6 h of contact time between the sorbent and the solution, were applied to rainwater samples spiked with the mixture of PTEs and resulted in removals of 30–90% for Zn(II), 11–78% for Cu(II), and 11–97% for Pb(II), generally lower than those expected by the models, 91% for Zn(II) and 52% for Cu(II), highlighting that the rainwater matrix interferes with the removal of PTEs by peel. However, the white bean peel may be an alternative as sorbent to reduce Zn(II), Cu(II), and Pb(II) concentrations in rainwater, since it is a natural and sustainable material.

Environmental and human health risk assessment of potentially toxic elements in rehabilitating iron mine lands in the Brazilian Amazon.

Waste pile substrates from Fe mining may carry potentially toxic elements (PTE). Rehabilitation efforts must maintain soil vegetation cover effectively, avoiding the dispersion of particulate matter and reducing the risk to the environment and human health. Therefore, this study aims to evaluate the pseudo-total and extractable contents, perform chemical fractionation, and assess the bioaccessibility and risk of PTE in waste piles of Fe mining in the Eastern Amazon. Soils were sampled from waste piles in different stages of environmental rehabilitation and from non-rehabilitated and native forest areas. The waste materials exhibit mean pseudo-total concentrations of Zn, Ni, Cr, and Cu that exceed the Brazilian soil quality threshold. However, they do not surpass reference values for human health safety. In addition, these elements are predominantly associated with the residual fraction, suggesting low availability. Among the 11 PTE evaluated, only Al, Cu, Fe, Mn, and Zn presented concentrations that were bioaccessible to the gastrointestinal tract. At the same time, Al, Fe, and Mn showed lung bioaccessibility. Soil properties limiting PTE extractability and bioaccessibility include pH and base saturation. Considering only elements above threshold levels, no environmental risk was observed, and the human health risk was considered insignificant for adult oral and inhalation exposure routes. Finally, the results show that high pseudo-total PTE contents in the analyzed Fe waste piles do not necessarily indicate high risks. However, substrate properties should be monitored over time to better understand their potential impacts and the main factors influencing their bioavailability.

Particulate matter and potentially toxic element content in urban ornamental plant species to assess pollutants trapping capacity.

Urban environments are usually polluted by anthropogenic activities like traffic, a major source of potentially toxic elements (PTEs), and ornamental plant species may reduce contamination by trapping traffic-related air pollutants in their leaves. The purpose of this study was tested the trapping pollutant capacity of four species commonly used in green areas of Seville city (SW Spain) to better choose species in urban green planning. Composition of particulate matter (PM) obtained from foliar surfaces (sPM) and wax-included (wPM) was determined by EDX-SEM analysis in samples from different city locations. Concentration of different PTEs (Ba, Cd, Cr, Cu, Fe, Mn, Ni, Pb, V and Zn), by microwave induced-plasma optical emission spectroscopy (MP-AES) were also analyzed in unwashed leaves of one of the selected species (Citrus aurantium) since it is the most cultivated species in Seville. Results showed that Nerium oleander was the plant species which trapped best superficial total and coarse PM. This capacity was enhanced by the presence of a waxy-cuticle and by cuticle thickness but not by leaf hairs. The only species unable to trap fine particles was Bougainvillea glabra. The most representative sPM on leaf surfaces from all species was the largest fraction (59-75%), followed by coarse (25-37%) and fine fractions (2.2-4.4%). In the wax PM, 48% of coarse particles were found in Citrus aurantium. Particulate matter deposited on surface foliage in general did not vary seasonally, while the large fraction of wPM in summer was significantly higher than in winter. The seasonal differences also existed in the level of PTE (Cd, Fe, Ni and V) in leaves. This work indicates that the leaf traits should be taken into account to evaluate the pollutants caption capacity, especially when planning of recreational green urban areas. Particulate matter composition was different according to the pollution sources and mostly contained Al, C, Ca, Fe, K, and Mg, but potentially toxic elements such as Si, As, Cr, Cu and Zn just accounted for 0.11-1.95% of the total elemental content.

Soil environmental monitoring of repurposed railway line operated for 75 years: case study in Northeast Poland

This study examines the environmental implications of repurposing former railway infrastructure into bicycle paths in northeastern Poland. While lauding the commendable initiative for offering eco-friendly transportation alternatives, the investigation emphasises the potential environmental and consequences linked to contaminated soils resulting from the former railway line, posing risks for both users and the environment. Topsoil samples (0-25cm) were collected from eight measurement points along the Szczytno - Biskupiec Reszelski railway line (Poland), at varying distances from the railway tracks (5-30m). Concentrations of specific Potentially Toxic Elements (PTEs), notably Ni, Zn, Pb, and Cd, were analysed in 48 topsoil samples. Furthermore, the soil contamination was assessed by contamination indices, single (Igeo, PI) and integrated (RI, (IPln, MERMQ). The study revealed variations in PTE concentrations, with the highest levels recorded at the fourth and seventh sampling sites (4:34.2-57.5mg/kg; 7:18.2-42.3mg/kg). These findings were consistently supported by the MERMQ and RI indices, emphasising the significant risks for the environment and increased soil toxicity. In light of the EU's proposed Soil Monitoring Law, the research emphasises the need for robust data collection, analysis, and contamination monitoring practices to facilitate informed decision-making and sustainable environmental management in repurposed transportation infrastructure.

An overview of potentially toxic element pollution in soil around lead–zinc mining areas

Metal mining activities have been major contributors of potentially toxic elements (PTEs) in the environment, leading to substantial soil pollution. One such example is lead–zinc mining around the world. Elevated concentrations of PTEs are commonly detected in nearby areas of both active and abandoned mines. This is primarily attributed to the release and dispersal of untreated waste materials from these mines into the surrounding environment. Mining-related soil pollution with PTEs can pose many different kinds of risks in a variety of contexts such as eco-toxicity, phytotoxicity, human health risk, as well as soil and water pollution. This review summarizes available data in the literature (2000–2023) on PTEs polluted soils originating from lead–zinc mining areas across the world. In this study, an attempt has been taken to evaluate the pollution level of PTEs in soils using collected data. The study shows the most polluted world regions are reported in Asia, followed by Europe and Africa, and only a few studies are reported in north, central and south America. The elements commonly analyzed in conjunction with Pb and Zn were Cd and Cu, whereas those responsible for increased pollution were Cd > As > Cu > Hg–Mn–Tl. Assessment of the pollution and health hazards has shifted to include a variety of quality indexes, including multivariate statistical analyses and microbial diversity.

Human health risk assessment from potentially toxic elements in the soils of Sudan: A meta-analysis.

Potentially toxic elements (PTEs) in soils threaten human health through several exposure pathways. However, health risks posed by PTEs in soils in developing countries have not yet been comprehensively investigated. Thus, such countries lack important information that is needed to implement sustainable solutions. In this study, we assessed the human health risks for 10 PTEs, including arsenic (As), cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), mercury (Hg), manganese (Mn), nickel (Ni), lead (Pb), and zinc (Zn), in Sudan focusing on soils affected by anthropogenic activities, such as industrial processes, gold mining, tannery, waste dumping, traffic (affecting roadsides), urban/rural agriculture, river, and coastal sediment land uses (LUs). For this purpose, we did a meta-analysis using 3430 PTE concentrations reported from 981 anthropogenically-affected soils in 76 publications between 1996 and 2024. Ingestion was the most common exposure pathway for both carcinogenic and non-carcinogenic PTEs. Hg and Mn were the main non-carcinogenic PTEs leading to adverse health effects in children in industrially-affected soils and coastal sediments, with average hazard quotient (HQ) and hazard index (HI) values >1. Cr and Ni caused the highest carcinogenic risk to children in all anthropogenically-affected soils as indicated by average incremental lifetime cancer risk values (ILCR >1×10-4). Further major cancer risks for children were caused by As in urban agricultural and industrial LUs, Cd in >70% of all LUs, and Pb at industrial and waste dump sites. Adults were under high cancer risks due to Cd in waste dump (ILCR=9.09×10-4) and Cr and Ni (ILCR >1×10-4) in >75% of all LUs. Cd contributed >50% and >70% to ILCR for children and adults along roadsides, respectively. Our findings can guide future research on the links between soil PTEs and human health risks in developing countries. We recommend establishing effective management strategies to reduce risks to human health based on the presence of PTEs in Sudanese soils.

INFLUENCE OF WASTEWATER TREATMENT TECHNOLOGY AND SLUDGE STABILIZATION ON THE SORPTION CAPACITY OF SEWAGE SLUDGE

This article investigates the influence of sewage sludge treatment processes and stabilizationmethods on metal-binding capacity and susceptibility to metal remobilization from sewagesludge. The materials (stabilized sewage sludge) were collected from two mechanical-biologicalsewage treatment plants located in an industrial area in southern Poland (Silesian Province):1) one with nutrient removal (nitrogen and phosphorus) and anaerobic sludge digestion (WWTPIII),and 2) a facility without nutrient removal and with aerobic sludge stabilization (WWTP-II).Concentrations of PTEs in sewage sludge samples were measured using the inductively coupledplasma optical emission spectrometry (ICP-OES). Sewage sludge from WWTP-III showeda significantly higher sorption capacity for Cu ions (20–50%) and Ni ions (50% to 2.5-fold) ascompared to sewage sludge from WWTP-II. However, sewage sludge from WWTP-II exhibiteda higher sorption capacity for Cd ions. The studied potentially toxic elements (PTEs), irrespectiveof anion type, formed unstable bonds with sewage sludge, which may lead to their desorption intothe environment. The high mobility of Cd, Cu, Ni and Zn ions in chloride and sulphate system, aswell as the low susceptibility to Cr ion release, should be considered in various applications of thetested sewage sludge.

Unveiling the nutritional value and potentially toxic elements in fish species from Miliç Wetland, Türkiye: A probabilistic human health risk assessment using Monte Carlo simulation

This study evaluates the nutritional value and health risks of fish from Miliç Wetland, Türkiye, focusing on potentially toxic elements (PTEs) in Esox lucius, Squalius cephalus, and Carassius gibelio. Using ICP-MS, mean PTE concentrations were determined, including Zn (4979 μg/kg), Fe (4241 μg/kg), and As (125 μg/kg). Macro elements like K, P, and Ca were also assessed for nutritional profiling. A Monte Carlo-based risk assessment confirmed that PTE levels were below safety limits, indicating safe consumption. Chemometric techniques (PCA, PCC, HCA) helped trace contamination sources, identifying residential, agricultural, and lithogenic inputs. Esox lucius showed the highest essential nutrient levels. This research highlights the importance of combining chemometric analysis with regular monitoring for food safety and public health protection.

Correlation Analysis of Ecosystem Reduction and Retention Effects and Spatial Distribution of Soil Potential Toxicity Elements.

Soil contamination by potentially toxic elements (PTEs) poses a significant threat to crop quality and human health, making it a global concern. However, the distribution patterns of PTEs across different land-use types are not well understood. To investigate the relationship between the reduction and retention effects of various ecosystem types on soil PTEs, we analyzed five categories of target elements in 299 soil samples from the southeastern Yunnan Province. Using the intelligent urban ecosystem management system's surface source control (runoff) model, descriptive statistical methods, spatial interpolation analyses, and GIS, we simulated the effects of different ecosystem types on soil heavy metals. This approach allowed us to examine the spatial correlations among ecosystem reduction, retention, and PTE distribution in soils. Our results indicate that soil PTE concentrations were indicative of a high-background value area, with concentrations of arsenic, cadmium, copper, lead, and zinc exceeding risk screening values. The coefficients of variation for arsenic, cadmium, and lead were extremely high and attributable to high external anthropogenic interference. Soil heavy metal reduction and spatial distribution were affected by the ecosystem's control function, and different ecosystems had different reduction effects. The reduction simulations for As and Pb were concentrated in building areas, while those for Cd and Zn were primarily focused on water bodies. The reduction simulations for Cu were concentrated in the forested areas. In conclusion, ecosystem reduction and retention influence heavy metal distribution, which is essential when planning green ecological development and construction.

Comprehensive analysis and risk assessment of fine road dust in Abbottabad city (Pakistan) with heavy traffic for potentially toxic elements

Human activities have far-reaching impact on natural ecosystems, causing increasing disturbances and disruptions to the delicate balance of the environment. Poor land use planning, urbanization, infrastructure development, and unplanned tourism exacerbate contamination and degradation in tourist destinations, yet the pollution of potentially toxic elements (PTEs) in these environments remains inadequately explored. To address this issue, we investigated the concentrations of acid-digested PTEs in road dust in Abbottabad city (Pakistan) with heavy traffic. The current study also evaluated PTE associated pollution, ecological and health risks, and potential sources of these elements. The average concentrations (in mg kg–1) of PTEs in road dust were highest for Fe (15540), followed by Mn (304), Zn (139), Cu (50.0), Pb (21.5), Cr (13.0), Ni (10.3), Co (6.66), and Cd (0.236). The levels of Co, Cr, Mn, Ni, and Fe were below the upper continental crust (UCC) averages, while Cd, Cu, Pb, and Zn exceeded them. Spatially, Cd, Cu, Pb, and Zn were found at higher levels near traffic hotspots, bus stands and automobile workshops. Road dust in Abbottabad exhibited unpolluted to moderate pollution levels (geo-accumulation index), with Cd, Cu, Zn, and Pb at 23% of the sites. The enrichment factor results indicated a significant anthropogenic influence, with Cd being significantly enriched and Zn, Cu, and Pb moderately enriched. The contamination factor results revealed moderate contamination by (Cd: 2.62, Zn: 2.08, Cu: 1.79, Pb: 1.27). Single metal risk index showed that 61% of the sites posed considerable to very high ecological risks due to Cd, which was highlighted as a significant concern. The absolute principal component scores-multiple linear regression model identified three factors contributing to PTE pollution: lithogenic (Co, Fe, Mn, Ni), traffic-related (Cd, Cu, Pb, Zn), and mixed sources (Cr), with contributions of 52.8%, 35.8%, and 11.4%, respectively. The PTE hazard quotient and total hazard index values for children and adults were below the safe risk level of 1, indicating no non-carcinogenic health risks. The cumulative carcinogenic risk values to the residents were also within acceptable limits. However, children's susceptibility to non-carcinogenic risks is higher due to their behavior and lower body weight. This study highlights the accumulation of PTEs in Abbottabad's environment, which poses challenges to long-term sustainability, particularly amid unplanned tourism. Therefore, urgent measures are necessary to mitigate PTE pollution and preserve tourist spots and public health.

Early-warning ecological risk assessments of multi-element pollution in the surface soil of karst basins in southwest China based on the delayed geochemical hazard model.

Soil potentially toxic element (PTE) pollution, especially in karst regions, poses significant ecological risks due to the unique geological features and environmental conditions. This study focuses on the delayed geochemical hazard (DGH) model to assess the progressive risks of cadmium (Cd) and lead (Pb) contamination in the surface soils of karst regions in southwestern China. The study found that Pb and Cd pollution in karst areas presents ecological risks, with the region's high porosity and alkaline soils facilitating the transformation of pollutants from stable to mobile forms. The analysis revealed that Pb underwent multidirectional transformations, with 28.3 % of the soil showing a transition from carbonate-bound Pb (PbC) to exchangeable Pb (PbE). However, Cd primarily transformed into carbonate-bound (CdC) and oxide-bound (CdO) forms, with 3.77 % of samples exhibiting the highest outbreak probability for the pathway from sum Cd (CdE+C+F+O+R) to CdC+O. In Pb-Cd co-contamination, Cd predominates, altering risk pathways by triggering transformations at iron-manganese oxide and organic matter binding sites, thereby increasing pollutant mobility. The most prominent combined risk pathway in Pb-Cd contamination was the shift from ME+O to MC (outbreak probability: 5.66 %), indicating enhanced mobility of both PTEs. New pathways also emerged, such as the transition from ME+C+F+O to ME+C, suggesting that Pb and Cd interactions accelerate the risk evolution, favoring highly mobile forms. These findings highlight the importance of not only considering total PTE concentrations but also their speciation and potential transformations in risk assessments. The DGH model effectively predicts evolutionary risks in co-contaminated karst areas, providing insights for early warning of multi-element pollution, particularly in vulnerable karst landscapes.

Health risks associated with potentially toxic elements in three fish species from Betoya Bay, Morocco: An integrated approach to human health risk assessment

This study examines the concentrations of arsenic (As), cadmium (Cd), chromium (Cr), cobalt (Co), copper (Cu), iron (Fe), mercury (Hg) and zinc (Zn) in three fish species (Sardina pilchardus, Engraulis encrasicolus, Trachurus trachurus) from Betoya Bay, collected in winter and summer. Significant variations were observed between tissues (p < 0.05), with the liver being the most contaminated. A seasonal increase in Potentially Toxic Elements (PTEs) was observed during the wet season, particularly for As, Cd, Hg and Zn in S. pilchardus. The Metal Pollution Index (MPI) showed no overall toxicity except in the liver (3.07–6.69). The Estimated daily intake (EDI) values remain below the provisional tolerable daily intake limits, indicating no health risk. However, Cd and Fe values exceed these limits in children. The Hazard Quotient (HQ) and Total Hazard Quotient (THQ) indices associated with muscle consumption suggest a non-carcinogenic risk for adults. For children, a hazard was identified for iAs in S. pilchardus in winter and in T. trachurus in both seasons. Furthermore, the carcinogenic risk indices (CRiAs and CRCr) indicate a potential risk for certain species, both for adults and children, highlighting the need for measures to reduce PTE contamination. In the short term, PTE concentrations in fish do not appear to pose an immediate risk to human health or ecosystems. However, there is evidence of long-term accumulation due to human activities, which could be of concern. It is recommended that bioaccumulation analyses and exposure monitoring of local populations be included in future studies to better anticipate and manage potential risks.

Field determination of trace concentrations of hazardous metals in waters by portable EDXRF.

A new effective method has been developed for field determination of trace concentrations of cadmium, arsenic, zinc, copper, nickel, chromium, and lead in waters (e.g., surface and wastewater) using an energy dispersive X-ray fluorescence (EDXRF) analyzer. Trace concentrations cannot be determined by EDXRF without preconcentration. Agar was used for the preconcentration of these potentially toxic elements (PTE). Metals are trapped in the three-dimensional network of agar gel. Subsequent swelling of the gel leads to more effective preconcentration. The swollen gels with PTE were analyzed by a portable energy dispersive X-ray fluorescence analyzer Delta Professional X (pXRF). The preconcentration factors for each PTE were determined. With pXRF, the detection limits were 7, 5, 6, 7, 9, 47, and 22 µg/L for Cr, Ni, Cu, Zn, As, Cd, and Pb, respectively. A reference material was used to assess the methodology performance, and it has a very good agreement. The optimized and verified methodology was tested in practice at the special chemical unit of the Fire Rescue Service of the Czech Republic. PTE were determined by pXRF in a mobile chemical laboratory in field analysis. The measured values were compared with those determined via inductively coupled plasma mass spectrometry (ICP-MS) and were in good agreement. Our method was applied to real wastewater samples collected during after a fire of accumulation batteries of domestic photovoltaic power plants, allowing accurate real-time estimation of PTE concentrations. Obtaining reliable data during an ecological accident has a very important role in minimizing the subsequent environmental impact of the accident.

Calculating the effect of intensive use of urban organic waste on soil concentrations of potentially toxic elements in a peri-urban agriculture context in Norway

BackgroundRecycling nutrients and organic matter available as waste in urban areas may close nutrient gaps and improve soil quality, but the concentrations of potentially toxic elements (PTEs) are commonly higher than in mineral fertilisers. How quickly may the limits for soil quality be exceeded, and for which elements, if such materials are applied intensively? For a rough answer to this question, we used soil data from ten case farms near Oslo and Bergen (Norway) to estimate how PTE concentrations increased when the demand for nitrogen (N), phosphorus (P) and potassium (K) in a theoretical carrot crop produced every year was covered by compost or digestate from source-separated food waste, or composted garden waste, compared with manure from horses and poultry which are often kept in peri-urban areas.ResultsWith the intensive fertilisation assumed here, the Norwegian soil quality limits for PTEs were reached within 20–85 years, and faster for soil with more organic matter since regulatory limits set by weight discriminate soils with low bulk density. The limits were reached first for Cu and Zn, which are both essential micronutrients for crop plants. The concentrations of macronutrients in the urban waste-based fertilisers were not well balanced. Rates covering the K demand would lead to high surpluses of P and N. In peri-urban vegetable growing, high applications of compost are not unusual, but more balanced fertilisation is required.ConclusionsThe Norwegian regulations for PTEs in organic soil amendments and agricultural soil are stricter than in the EU, and do not support recycling of organic matter and nutrients from urban waste. Many materials which can only be applied with restricted amounts to Norwegian agricultural soil, may be applied according to crop demand in the EU. Growers utilising urban waste-based fertilisers intensively should monitor the soil regularly, including PTE analyses. Soil sampling should occur on fixed sampling points to reveal changes in concentrations over time. Norwegian authorities should consider a revision of the organic fertiliser regulation to support recycling of valuable organic materials. There is a need for more data on the PTE concentrations in agricultural soil and organic fertiliser materials.

Leaf Accumulation Capacity of Herbaceous Plants Growing on Fields Contaminated With Anthropogenically Induced Potentially Toxic Elements Under Natural Soil Conditions

ABSTRACTEstimation and knowledge of potentially toxic elements (PTEs) in soils and herbaceous plants are vital for ecotoxicological reasons. This study explored PTE accumulation in the aerial organ (leaf) of herbaceous plants in PTE‐contaminated soils in a linear transect of three localities close to the Litavka River in Pribram, Czech Republic. Leaf accumulation answers questions on PTE hyperaccumulation and removal during phytoremediation. The study adopted the pseudo‐total extraction (aqua regia soluble) of PTE contents (Cd, Cu, Zn, Pb, and Ni) of soil and leaf samples determined by inductively coupled plasma optical emission spectroscopy. Except for Ni, the contents of Cd, Cu, Pb, and Zn were above the permissible limits in soil following WHO with contamination factors ranging from moderate to serious contamination in the sites. Of the 118 herbaceous species in the sites, 43% (52 species) accumulated Cd above the WHO limit in leaves with Geranium pusillum Burm. f. having the highest content (0.84 mg kg−1) while only Geum urbanum L. (132 mg kg−1) and G. pusillum (166 mg kg−1) were above the limit that supports the principal option to clean the infested soils. There was a low bioaccumulation of all plants indicated by a bioaccumulation factor less &lt; 1 (BAFleaf &lt; 1) with PTE content lower than reported hyperaccumulator values. The hyperaccumulation status of PTE of plants stated by previous authors in leaves can be unreliable, under natural soil conditions, accumulations can even be lower than the permissible limits. Further studies requiring different soils and other plants are needed to make a reliable inference on which organs of plants support hyperaccumulation status.

Evaluation of 210Po, 210Pb, and potentially toxic element concentrations in aquatic environments and polychaetes along the southeast coast of Chennai, Tamil Nadu: a baseline report

ABSTRACT The activity concentrations of radionuclides (210Po and 210Pb) and the concentrations of potentially toxic elements (PTEs) in water, sediment, and two polychaete species (Marphysa madrasi and Namalycastis jaya) collected from 12 stations, denoted as S1 to S12, along the coast of Tamil Nadu, Chennai, in southeast India has been investigated. The average activity concentrations of 210Po and 210Pb were 0.39 ± 0.01 mBq/L and 3.30 ± 0.06 mBq/L in water, and 0.80 ± 0.02 Bq/kg and 4.21 ± 0.19 Bq/kg in sediment, respectively. Marphysa madrasi exhibited higher 210Po and 210Pb activity concentrations (37.78 ± 0.43 Bq/kg and 17.25 ± 0.22 Bq/kg, respectively) compared to Namalycastis jaya (34.40 ± 0.42 Bq/kg and 15.91 ± 0.26 Bq/kg, respectively). Maximum activity concentrations for both radionuclides in water were observed at Kalpaakam (S11) and Nemmeli (S7), while maximum sediment activity concentrations were found at Nemmeli (S7). The elevated activity concentrations in polychaetes from Nemmeli (S7) likely reflect the significantly higher 210Po and 210Pb activity concentrations observed in sediments from this site when compared to other sites. Bioaccumulation values for 210Po and 210Pb averaged 6.89 × 101 and 4.20 for M. madrasi, and 6.17 × 101and 3.84 for N. jaya , respectively. Sediment PTE concentrations followed the order: Fe > Zn > Mn > Ni > Co > Cr > Pb > Cd > Cu. Risk assessment indicated alarming levels of PTE contamination in sediments, suggesting severe anthropogenic impacts. In contrast, average PTE concentrations in polychaetes followed the order: Fe > Cu > Zn > Mn> Cr > Ni > Co > Cd > Pb. Statistical analysis revealed strong and significant correlations (p < 0.05) between PTE concentrations in sediments and polychaetes. The present study offers baseline data for evaluatingthe levels of 210Po and 210Pb in water, sediment, and polychaetes in selected locations along Chennai, Tamil Nadu, India’s southeast coast. These findings lay the groundwork for further studies of polychaetes, specifically the ecological effects of PTEs and radionuclides on coastal creatures and biomagnification.