Environmental Geochemistry and Health最新文献

With rapid urbanization and industrialization, pollution of rare earth elements (REEs) in air, soil, and water is increasing in urban areas. These critical high-tech elements are becoming more abundant in urban dust and other environmental settings. It is difficult to differentiate and quantify the sources of REE pollution, as natural and anthropogenic sources overlap. This work couples isotopic tracing techniques (Pb, Sr, and Nd isotopes) with receptor models (positive matrix factorization (PMF) and absolute principal component scores/multiple linear regression (APCS/MLR)) to obtain robust source apportionment of REEs in urban environments. Isotopic fingerprints, including Gd anomalies, have been shown to serve as powerful tracers for distinguishing vehicular emissions, industrial discharges, and soil erosion. Non-exhaust vehicular emissions, especially those from brake and tire wear, have been identified as the main sources of REE release into the environment. The combination of isotopic methods and receptor models enhances the accuracy of source apportionment and contributions, facilitating better environmental management. The review highlights the need for standardized isotope libraries and sophisticated modelling tools to characterize sources, thereby improving source apportionment and informing sustainable control strategies for urban pollution. Focusing on controlling industrial and vehicle emissions can be an effective strategy to reduce REE contamination levels and human exposure.

Urban uncontrolled landfills in Kinshasa generate metal-rich leachates that contaminate surrounding freshwater streams, sediments, and biota. To assess the extent of this contamination, sediment from six freshwater streams in Kinshasa (N'djili, Limete, Lemba, Selembao, Mont-Ngafula, Makala) were analyzed to assess contamination by heavy metals-including Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Mo, Cd, Sn, Sb, Pb and Hg-and bioaccumulation in terrestrial (Lumbricus terrestris) and aquatic (Tubifex tubifex, Nais elinguis, Enchytraeus albidus) oligochaetes. Sediments were digested following the Swiss Federal Soil Ordinance (OSol 814.12) and analyzed using ICP-MS for metals and a Direct Mercury Analyzer (CV-AAS) for total Hg. Oligochaete tissues were freeze-dried, acid-digested (HNO₃-HClO₄), and analyzed using the same instrumentation. Sediment pollution levels were assessed using the Geoaccumulation Index (Igeo), Enrichment Factor (EF), contamination factor (CF), and the overall Ecological Risk Index (RI), while ecological thresholds were compared to the Canadian Sediment Quality Guidelines. Bioaccumulation factors (BAF) were calculated to quantify metal transfer from sediments to organisms. Sediments showed strong contamination at landfill-impacted sites, with Hg reaching 3.8 mg·kg⁻¹ dry weight-far exceeding Canadian SQGs (TEL: 0.17 mg·kg⁻¹) and PELs (0.486 mg·kg⁻¹). Cu and Zn were also highly elevated (up to 687.9 and 995.3 mg·kg⁻¹, respectively). RI values were highest at Limete (1014-3552.7), indicating very high ecological risk. Aquatic oligochaetes exhibited greater bioaccumulation than terrestrial species, with Hg up to 0.876 mg·kg⁻¹ and Cu up to 93.1 mg·kg⁻¹. High BAFs were observed, particularly for Cd (118.2 at Mont-Ngafula) and Sn (263.1 at Makala), confirming strong sediment-to-organism transfer. Fine, organic-rich sediments and proximity to landfill leachates were positively correlated with metal contamination and bioavailability.

This study investigated the hydrogeochemical characteristics of surface waters in the Congonhas Mineral District (CMD), located in the southern portion of Quadrilátero Ferrífero, Brazil. A total of 38 sites were monitored between 2021 and 2024 to understand seasonal and spatial variability across distinct lithologies and land uses. Hydrogeochemical patterns revealed dominant mixed bicarbonate facies associated with metavolcano-sedimentary terrains, while domains of granitoids exhibited alkali enrichment. Waters under the influence of larger Urban settlements were enriched in Na, Cl, sulfate, and nutrients. By integrating geospatial classification, seasonal sampling, and robust statistical techniques, we investigated the behavior of Fe and Mn, key elements influenced by both natural geological sources and mining activities. Reference values for geochemical background and baseline thresholds, based on samples from preserved and mixed land use areas, respectively, were estimated using three distinct statistical approaches. Among these, the upper tolerance limit (UTL) method was considered the most consistent and suitable. Spatial and seasonal patterns revealed elevated Fe and Mn levels during the rainy season, particularly in areas influenced by mining and urbanization. The proposed reference values provide a realistic basis for identifying contamination, and can give support for more realistic regulatory frameworks, and definition of strategies for water quality management. The obtained results highlight the relevance of tailored guidelines in mining contexts, where reference values adopted by regulatory agencies may not reflect local geochemical conditions.

Cadmium (Cd) pollution poses a serious threat to aquatic environmental safety and sustainable agricultural development. Biogenic iron (Fe)-manganese (Mn) oxides (BFMO), mediated by Mn-oxidizing bacteria, are promising natural adsorbents for Cd removal. Although iron-manganese oxides have been widely studied for application in wastewater treatment, BFMO synthesized via a fully biologically driven process using novel strains still face limitations in terms of material structure and the availability of active sites. In this study, BFMO was synthesized using a newly isolated strain of Stenotrophomonas sp. Z-MRQA-3, and its mineralogical properties, Cd(II) immobilization performance, and underlying mechanisms were systematically investigated. The results demonstrated that BFMO possesses a high specific surface area (244.52 m²/g), a hierarchical porous structure, and abundant surface functional groups, which collectively contribute to its superior adsorption capacity. Under conditions of adsorbent dosage of 0.5 g/L, initial Cd(II) concentration of 50 mg/L, and pH 7.2, the removal efficiency of Cd(II) reached 96.52%, with an adsorption capacity of 80.83 mg/g. The adsorption process followed the pseudo-second-order kinetic model and the Langmuir isotherm model, with a theoretical maximum adsorption capacity of 89.29 mg/g. Mechanistic studies indicated that Cd(II) immobilization occurs mainly through surface complexation, ion exchange, and co-precipitation, facilitated by the redox-active multivalent Mn and oxygen-containing functional groups. This study aims to investigate the unique advantages of in situ synthesizing BFMO using specific bacterial strains. This work offers fundamental insights and practical prospects for developing green, efficient, and sustainable technologies for remediating Cd-contaminated water.

The socio-economic constraints-driven under provision of scientifically designed landfills for effective management of hazardous industrial wastes like tannery solid waste (TSW) in the developing countries. Disposal of TSW at designated and non-designated open dumps (OD) renders seasonal leachate runoff into adjacent agricultural fields when intense precipitation hits mountainously stacked TSWOD during summer and winter monsoon. However, TSWOD driven impacts on soil and crop productivity and biosafety of the adjacent agricultural fields has been missing in the literature. The objective of the current study was spatiotemporal quantification of productivity and biosafety threats of seasonal TSW leachate to recurrent corn and potato food crops in the adjoining agricultural fields of TSWOD of combined effluent plant of KTWMA, Kasur Pakistan. Based on data collected from two agricultural fields (2 ha each), it was observed that: (1) the TSW leachate arising from TSWOD severely affected soil productivity potential due to its immoderate pH, EC, COD, and BOD; being significantly higher than the local irrigation water; (2)Cd, Cr. Cu, Mn, Ni, Na and K in the TSW leachate exceeded the provincial industrial effluent discharge limits and had significant impact on soil health than the non-polluted fields; (3) the productivity of corn and potato in polluted fields remained as low as one third of the productivity in non-polluted fields; (4) the environmental contaminants' food biosafety hazards were determined as metal pollution index being variable for different metals, hazard index (HI < 1.0), and risk quotient (chronic risk with 1.0 level of concern). (4) Statistically, the productivity decline of corn and potato crops was function of the changes in soils chemistry. The study concluded that TSWOD seasonal leachate increasingly reduced suitability of adjoining soils for safer edible cropping by significantly reducing productivity and posing long-term biosafety hazards caused by vulnerability of food chain to heavy metals and organic pollutants.

Agroecosystems, which sustain global food production and economic stability, face increasing threats from emerging contaminants such as microplastics, Per- and polyfluoroalkyl substances (PFAS), pharmaceuticals, and engineered nanomaterials (ENMs). These pollutants persist in the environment, bioaccumulate in crops, and impose complex risks to soil health, biodiversity, and human well-being. Microplastics derived from agricultural plastics and sewage sludge disrupt soil structure and microbial communities, while PFAS migrate into groundwater and contaminate drinking water supplies. Pharmaceuticals introduced through wastewater irrigation and manure application accelerate antimicrobial resistance, and ENMs used in agrochemicals influence nutrient dynamics and soil chemistry. Despite growing recognition of these hazards, regulatory responses remain fragmented and current risk-assessment frameworks insufficient. This review synthesizes advanced detection tools-including CRISPR-based biosensors, machine-learning contamination mapping, and high-resolution spectroscopy-with sustainable remediation strategies such as phytoremediation, biochar amendments, and nano-enabled pollutant degradation. By comparing emerging contaminants with conventional pollutants, this work establishes their unique persistence, mobility, and policy challenges while linking their impacts to Sustainable Development Goals (SDGs) 2, 3, and 6. Importantly, the review emphasizes that long-term resilience of agroecosystems requires coordinated global policy alignment, integration of interdisciplinary monitoring systems, and stakeholder engagement to reduce contaminant loads. Future research should prioritize harmonized toxicity thresholds, long-term field experiments on contaminant-crop interactions, and scalable, low-cost detection platforms suitable for resource-limited regions. Together, these efforts will be essential for mitigating EC-related risks, strengthening food security, and safeguarding environmental and public health.

Minerals containing iron (Fe) and phosphate can simultaneously immobilize cations such as lead (Pb) and oxyanions including arsenic (As) and antimony (Sb). However, phosphate released from these minerals substitutes for adsorbed As and Sb and increases metal(loid) mobility, which limits their practical effectiveness. Vivianite [Fe₃(PO₄)₂·8(H₂O)], an Fe-phosphate mineral with low phosphate release potential, offers a promising solution for the simultaneous stabilization of cationic and anionic contaminants. This study evaluated the effectiveness of vivianite for concomitant immobilization of arsenite [As(III)], arsenate [As(V)], antimonite [Sb(III)], antimonate [Sb(V)], and Pb(II) in single- and mixed-metal(loid) solutions and contaminated soils. The adsorption of As(III), As(V), and Sb(III) onto vivianite followed the Langmuir isotherm model, indicating monolayer surface interaction. In mixed-metal(loid) solutions containing As or Sb with Pb, immobilization increased by 73% for As(III), 3271% for As(V), and 12% for Sb(III) compared to single-metal(loid) solutions. For Sb(V), immobilization increased from 0% in single-solution to 83% in mixed-metal(loid) solution. Phosphate released from vivianite reacted with Pb(II), resulting in Fe release. The liberated Fe subsequently reacted with As and Sb and enables their simultaneous immobilization. Application of vivianite decreased the concentrations of bioavailable As and Pb by 23% and 52%, respectively, in mixed-metal(loid) contaminated soil. In single-metal(loid) contaminated soil, bioavailable Sb and Pb were reduced by 16%, and 19%, respectively, compared to the control. Iron phosphate amendments often failed to achieve simultaneous stabilization of Pb and As because phosphate release promoted As remobilization. In contrast, vivianite enabled concomitant immobilization of both toxic oxyanions and cationic metals in soil during prolonged incubation by limiting phosphate release to levels insufficient to competitively displace As.

Atmospheric deposition plays a significant role in introducing cadmium (Cd) into agroecological systems; however, the understanding of its accumulation and toxic effects on crops through foliar and root uptake remains limited. In this study, we simulated atmospherically deposited Cd using cadmium sulfide (CdS) nanoparticles. A factorial pot experiment with both foliar and soil exposure to CdS was conducted to investigate the bioaccumulation and phytotoxic effects of simulated deposited Cd in wheat. The results indicated that Cd concentrations in various wheat tissues (roots, stems, leaves, husks, and grains) significantly increased (p < 0.05) under both exposure pathways. For grains, foliar exposure increased Cd levels by 14-fold with a low dose of exposure and by 90-fold with a high dose of exposure. Under soil exposure, grain Cd levels increased threefold in the low-dose exposure and ninefold in the high-dose exposure. Foliar exposure led to a greater increase in Cd accumulation in grains compared to soil exposure, suggesting that foliar absorption may be the primary pathway for Cd accumulation from simulated atmospheric deposition in the edible parts of wheat. Additionally, foliar exposure resulted in more pronounced reductions in leaf antioxidant enzyme activities (SOD and CAT, 23-39%) and sulfhydryl (-SH, 17-50%) content, indicating potentially more severe oxidative damage from foliar exposure. However, the concentrations of essential mineral elements (Ca, Mn, Zn, Fe) of grains significantly decreased under both exposure pathways. Furthermore, both exposure modes significantly altered the protein and amino acid content of the grains. Under high exposure levels, the tyrosine content of grains significantly decreased (approximately 9.5%) with foliar exposure, while the levels of valine, methionine, and isoleucine significantly decreased (11-59%) under soil exposure. These findings underscore the significant role of foliar absorption in Cd accumulation in wheat grains and suggest the phytotoxic effects of soil exposure to atmospherically deposited Cd.

Springs in tropical volcanic regions are vital resources for drinking water, irrigation, and sustaining local communities. However, rapid land use changes and intensified anthropogenic activities have contributed to the degradation of spring water quality. This study analyzed 13 physicochemical parameters in 30 spring samples from the southern slopes of Mt. Merapi, Indonesia, during the dry and rainy seasons to characterize seasonal hydrogeochemical dynamics, evaluate spring water quality, and assess associated health risks. The Water Quality Index (WQI) and Irrigation Water Quality Index (IWQI) were applied to determine suitability for drinking and irrigation, alongside a non-carcinogenic risk assessment based on nitrate (NO₃^-) and fluoride (F^-) ingestion. The results indicated that the groundwater facies were dominated by Ca-Mg-HCO₃ and mixed Ca-Na-HCO₃ types. Most springs had good to excellent WQI, confirming drinking suitability, whereas those influenced by agriculture and urban activities showed lower quality. The IWQI assessments similarly indicated generally good water quality, with low salinity and sodicity hazards, supporting the suitability of the water for irrigation. Statistical analysis revealed that seasonal variations did not significantly affect the hydrogeochemical composition or overall groundwater quality. Furthermore, NO₃^- and F^- contamination was closely linked to surface runoff and infiltration from agricultural and domestic wastewater. The Total Hazard Index (THI) of NO₃^- and F^- indicated that infants are more vulnerable to non-carcinogenic health effects than children and adults. These findings emphasize the link between spring water quality and human health, providing evidence for sustainable groundwater management in volcanic regions.

This study assesses the spatial variation, sources, and environmental and ecological risks of heavy metal and metalloid pollution in the surface soil of the Singrauli coal mine area, Madhya Pradesh, India. It analyses the intensity of pollution through the major pollution indices. Composite soil samples were collected from 14 sampling locations using the quartering method. Collected samples were digested and analysed for 14 elements by using Inductively Coupled Plasma Mass Spectrometry (ICP-MS). The concentration of these elements is used to compute 7 pollution Indices to determine the severity of pollution in the study area. Multivariate statistical analysis was conducted to identify the sources and processes contributing to metal pollution in the study area. The abundance of elements followed the order: Fe > Al > Mn >Ba > Zn > Cr > Cu > Ni > Pb > Co > B > As > Ag > Cd. The concentration of Cd (0.43 ± 0.18 mg/kg), Pb (15.73 ± 10.48 mg/kg), and Zn (83.00 ± 53.55 mg/kg) exceeded the mean USEPA recommended concentration for soil. The geo-accumulation Index showed a positive value for Pb (I_geo = 1.52). The enrichment factor showed a high enrichment for Mn, Cu, As, and Cd. Mean Contamination Factor values ranged between 0.03 (Ag) and 4.77 (Cd). Nemerow pollution index (NPI) values ranged from 1.08 to 5.67, suggesting slight to heavy pollution. The enrichment factor for Cd fell in a very high-risk zone (Er > 120). The potential risk index (PERI) across sites ranged from 47.46 to 275.07, suggesting a low to moderate ecological risk. Mean ERM quotient (MERMQ) values indicated the potential soil toxicity in the study area. The global implications of studying heavy metal pollution in soil, especially around coal mining areas, are widespread and impact various aspects of the environment, viz., sustainability, scientific research, agricultural productivity, human health and socio-economic development worldwide. This issue is recognised globally as a significant environmental problem that requires urgent global attention.