Environmental Geochemistry and Health最新文献

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.

This study investigates the sulfate durability performance of concrete incorporating lead-zinc tailings sand (LZTS) as partial replacement for fine aggregates. Greater emphasis is placed on long-term resistance to sulfate attack rather than on strength enhancement, ensuring full consistency with the manuscript title. Sulfate exposure conducted in a 5% Na₂SO₄ solution for periods of up to 180 days, during which mass change, linear expansion, surface degradation, and residual mechanical strength were systematically evaluated. The results demonstrate that optimized levels of LZTS replacement, in combination with low-dosage hybrid nanomaterials, significantly enhance the sulfate resistance while maintaining satisfactory mechanical performance. From a sustainability perspective, replacement of up to 50% of natural river sand is achievable, contributing to reduced depletion of natural resources. Microstructural observations obtained from SEM, supported by XRD and FTIR analyses, provide indirect yet consistent evidence of matrix densification and suppression of sulfate reaction products. FTIR spectra confirmed these observations by intensifying Si-O-Si and Al-O-Si bands and weakening Sulfate-associated vibrations with Heavy metal immobilization efficiency exceeding 90%. The findings reveal the potential of LZTS-based concrete as a durable and environmentally responsible construction material for sulfate-rich environments.

Graphitic carbon nitride (g-C₃N₄), a metal-free polymeric semiconductor, has attracted increasing attention for photocatalytic and biomedical applications due to its visible-light responsiveness, tunable electronic structure, and chemical robustness. However, its practical utility remains constrained by poor crystallinity, limited active surface sites, and rapid electron-hole recombination. In this study, a facile one-step calcination strategy was employed to synthesize highly crystalline, non-metal-doped g-C₃N₄ nanostructures with enhanced physicochemical properties. Structural and optical characterizations revealed improved crystallinity, expanded surface area, defect-rich architecture, and extended visible-light absorption. These features significantly boosted the photocatalytic performance for the degradation of Reactive Blue 222, achieving up to 89% removal within 90 min under visible light, with the degradation kinetics following a pseudo-first-order model (k = 0.97 min⁻¹). Beyond environmental remediation, the modified g-C₃N₄ also demonstrated notable anticancer activity against HCT-15 (colon cancer) cell lines. Cytotoxicity assays revealed concentration-dependent inhibition, with IC₅₀ values of 7.10 µg/mL, respectively, indicating its potential as a photodynamically active nanomaterial for cancer therapy. The dual functionality of visible-light-driven photocatalysis and selective anticancer activity underscores the potential of engineered g-C₃N₄ as a sustainable platform for integrated environmental and biomedical applications.

Radon, a naturally occurring radioactive gas produced from the decay of uranium in the subsurface, migrates upward through soil by diffusion and advection before being released into the atmosphere. As the second leading cause of lung cancer after smoking, understanding its behavior in the near-surface environment is essential for assessing environmental radiation risks. This study investigates depth-wise radon concentrations in soil gas, surface exhalation rates, and transport parameters in the soil of Chakrata region,  Garhwal Himalaya, India. Radon measurements were performed using a portable Smart RnDuo monitor at depths (Z) of 15, 30, and 45 cm. Soil-gas radon concentrations ranges from 237 to 6540 Bq m^-3 at 15 cm, 854 to 7831 Bq m^-3 at 30 cm, and 1020 to 8540 Bq m^-3 at 45 cm, indicating a systematic increase with depth. Surface exhalation rates varies between 1.25 and 16.19 Bq m^-2 h^-1, with a mean value of 6.42 Bq m^-2 h^-1, respectively. Radon transport parameters were derived using Fick's diffusion model, resulting in average values of 0.49 m for diffusion length (l_s) and 0.002 m²s^-1 for diffusion coefficient (D_s). Spearman's rank correlation analysis revealed that surface radon exhalation and diffusion parameters exhibit strong correlations. These findings provide baseline information on radon mobility and soil-gas dynamics in the region and will support future radon hazard assessment and environmental monitoring efforts in the Chakrata area of the Lesser Indian Himalaya.

The development of efficient and sustainable adsorbents is crucial for remediation heavy metal contamination in both aqueous and terrestrial environments. Biomass-derived biochar shows great promise, yet its adsorption performance is highly dependent on both the feedstock properties and the pyrolysis temperature. However, a systematic understanding of how temperature dictates the adsorption mechanisms, especially for multi-metal systems, remains limited for novel biomass precursors. Therefore, the stem pith of Medulla stachyuri (MS) was utilized to prepare biochars at different pyrolysis temperatures (400, 600, and 800 °C, denoted as MBCs) and to investigate their adsorption behavior for Pb²⁺ and Cu²⁺. The results indicated that higher pyrolysis temperatures significantly enhanced the specific surface area (reaching 322.94 m²/g for MBC-800) and ash content but decreased the oxygen-containing functional groups. MBC-800 exhibited superior adsorption capacities for Pb²⁺ (2139.25 mg/g) and Cu²⁺ (970.68 mg/g), with remarkable selectivity for Pb²⁺ in binary systems. Mechanistic studies revealed that the dominant adsorption mechanism shifted from surface complexation at lower temperatures to precipitation induced by the biochar's inherent inorganic components (e.g., SO₄²⁻ forming PbSO₄) at higher temperatures. Component contribution analysis quantitatively confirmed that the water-soluble fraction in MBC-800 was responsible for over 78% of Pb²⁺ immobilization. Furthermore, MBC-800 demonstrated excellent stability with the lowest desorption rate, indicating a low risk of secondary pollution. This work highlights the superiority of high-temperature biochar from MS for efficient and stable heavy metal removal, providing new insights into the precipitation-dominated mechanism and the high-value utilization of medicinal plant residues.