Environmental Geochemistry and Health最新文献

Water contamination with hazardous heavy metals, particularly cadmium (Cd) poses significant environmental and health risks due to its toxicity, persistence, and carcinogenic potential. This study evaluates the efficacy of cotton husk-derived adsorbents: natural cotton husk (CHN), cotton husk biochar (CHB), and a copper oxide nanocomposite (CHNC) for Cd removal from aqueous solutions. The adsorbents were characterized using Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and Brunauer-Emmett-Teller (BET) analysis, revealing distinct functional groups, surface morphologies, and porosity profiles. Batch adsorption experiments examined the effects of initial Cd concentration (1.25-20 mg/L), adsorbent dosage (0.5-1.5 g/100 mL), and contact time (15-120 min) under controlled pH (6.0) and temperature (26 ± 1°C). Results demonstrated that CHNC exhibited superior Cd removal efficiency (> 90%) due to enhanced surface area (21.174 m²/g) and multifunctional adsorption mechanisms, including electrostatic attraction and chemisorption. CHB showed intermediate performance (80-90%), while CHN exhibited the lowest efficiency (60-75%). Kinetic studies revealed that adsorption followed pseudo-second-order kinetics (R² > 0.99), indicating chemisorption as the dominant mechanism. Equilibrium data were well-described by the Freundlich isotherm (R² = 0.99), suggesting heterogeneous multilayer adsorption. Comparative analysis with previous studies highlights the cost-effectiveness and high adsorption capacity of cotton husk-based materials, particularly CHNC as compared with conventional adsorbents. This study underscores the potential of agricultural waste utilization for sustainable water treatment, offering a viable solution for Cd remediation in contaminated water systems.

The global reliance on antibiotics has led to the discharge of large amounts of their residues into rivers, lakes, and coastal waters. Antibiotic residues, even in small amounts, can damage ecosystems and human health. They can also lead to the development of antibiotic-resistant bacteria and genes. This review applies a source-impact-treatment framework to connect major antibiotic classes, usage patterns, and transport pathways with resistance-related environmental and public health concerns. Unlike reviews that focus on a single technology or material, this work provides a decision-oriented comparison of the two most widely used removal strategies: adsorption and advanced oxidation processes (AOPs). Recent advances are summarized by highlighting key materials, processes, performance trends, mechanisms, and practical limitations. Adsorption and AOPs are evaluated using unified criteria, including treatment cost, operating conditions, mineralization and by-product formation, toxicity reduction, and implementation challenges. This framework supports context-specific selection for various wastewater matrices and regional requirements, Moreover, this work identifies research gaps and future directions, such as the development of robust, low-cost materials, enhancement of mineralization with reduced secondary risks. In addition, it emphasizes the need to integrate treated wastewater reuse to more effectively assess sustainability and real-world applicability.

Radon (²²²Rn), a naturally occurring radioactive noble gas produced by the decay of uranium (²³⁸U), is present in rocks, soil, and groundwater. ²²²Rn dissolves readily in groundwater; therefore, it contaminates drinking water supplies, including bottled water, which increases internal radiation exposure through ingestion. Humans are exposed to naturally occurring radioactive materials (NORMs) in rocks, soil, and water. Variations in atmospheric, geological, and physical features result in an uneven distribution of radionuclides on the surface due to the uneven natural presence, transport, deposition, accumulation, and retention of radionuclides. Excessive ²²²Rn levels beyond the permissible limit in the environment can cause lung cancer. The primary aim of this study is to determine the ²²²Rn concentrations in commercially available bottled drinking water. A RAD7 H₂O detector was used to measure ²²²Rn concentrations in bottled water samples from 31 brands, each comprising three samples from various Saudi Arabian firms, to assess the potential effects of radioactive water pollution on human health from radiation exposure. Determine the population's annual effective radiation doses from ²²²Rn ingestion, baseline data for radiological quality control, and evaluate the possible health effects of ²²²Rn exposure from bottled drinking water. The dose contribution to different organs received by the ingesting and breathing routes has been examined. The study evaluates the ²²²Rn levels in the water, which ranged from 0.13 to 0.39 Bq.L^-1. Radiation doses were calculated to assess potential health risks associated with ²²²Rn exposure. The consumption of dissolved radionuclides in bottled drinking water contributed to an annual effective dose ranging from 1.28 to 3.84 µSv.y^-1, 2.23 to 6.69 µSv.y^-1, and 6.97 to 20.97 µSv.y^-1, respectively, for adults, children, and  infants with an average value of 1.69 µSv.y^-1, 2.95 µSv.y^-1, and 9.24 µSv.y^-1. The study found that the yearly effective doses from bottled waters are below the WHO's recommended limit of 0.10 mSv.y^-1. The data was compared to worldwide standards provided by several sources. The results are below both the USEPA's 11 Bq.L^-1 and the WHO's recommended level of 100 Bq.L^-1. This investigation found low levels of radioactivity in all water samples tested in the Kingdom of Saudi Arabia.

Coal mining activities have demonstrated substantial environmental contamination, posed severe risks and impacted to the surrounding soil ecosystems. However, the effects of a single crack particularly during its initial stage of formation caused by deep mining-induced cracks, which fundamentally modify soil structure and affect PTE concentrations near coal mining, are poorly understood. Understanding this redistribution is essential for assessing environmental risks and developing remediation strategies. Soil samples were collected along primary crack zones in abandoned subsidence affected soils in Shandong Province, China, and analyzed using ICP-MS for seven PTEs to evaluate geo-accumulation index, spatial distribution and potential health risk. The result showed that concentrations of As, Ni, Cr, and Zn exceeded Shandong background levels by 1.32, 1.14, 1.07, and 1.05 times, respectively, indicating anthropogenic enrichment. The Soil was slightly contaminated by As, Ni, and Cu based on geo-accumulation index. Spatial analysis presented that all PTEs had strong spatial similarity, revealing a high concentration in the deep main crack, whereas Hg exhibits a distinct distribution behavior. Except mercury, statistical correlation among PTEs indicating common geochemical pathways. Health risk assessment of PTEs showed that children face exposure risks, particularly from oral ingestion of As with risk of 2.06 × 10^-5. These findings demonstrate that subsidence-related cracking plays a critical role in modifying distribution of potential toxic elements in abandoned soils and elevated health risk of arsenic for children, providing essential knowledge for risk mitigation and land management strategies in mining-disturbed regions.

Groundwater, the largest accessible freshwater reserve, is increasingly threatened by the simultaneous presence of pathogenic microorganisms and toxic chemical pollutants, posing substantial risks to public health and ecosystem stability. While numerous studies address individual contaminants categories, integrated evaluation of microbial and chemical threats alongside sustainable treatment strategies remain limited. This review provides a comprehensive synthesis of contaminant sources transport mechanisms, survival dynamics and associated health burdens, highlighting the global scale of groundwater-related disease outbreaks and chronic toxicity risks. A critical comparative assessment of low-cost and sustainable remediation technologies including biological treatment systems, adsorption-based materials, permeable reactive barriers, membrane distillation, and electrocoagulation is presented. Key finding indicate that adsorption and bio-based system demonstrated high removal efficiencies (> 90% in several reported cases) with lower operational costs, while hybrid and passive technologies offer enhanced long-term sustainability for decentralized settings. The review identifies scalability, site-specific hydrogeological variability and lifecycle cost optimization as major research gaps. By linking treatment performance with risk-based management and Sustainable Development Goals (SDG 3 and SDG 6), this work advances an integrated framework for resilient and affordable groundwater restoration. Furthermore, the study highlights the need for hybrid treatment platforms and real-time monitoring integration to bridge laboratory innovations with field-scale implementation. Strengthening interdisciplinary collaboration is essential to translate technological advances into practical, policy-relevant groundwater solutions.

Arsenic (As) contamination in agricultural soils poses significant risks to food safety and human health, particularly in regions relying on As-contaminated groundwater for irrigation. This study evaluates the efficacy of iron-impregnated biochar (Fe/TBC) in mitigating As leaching and enhancing long-term immobilization in two contrasting soils (sandy loam PP1 and sandy U43) under simulated irrigation and accelerated aging conditions. Statistical analyses including ANOVA and MANOVA revealed that Fe/TBC significantly improved As retention (up to 88%) and reduced post-aging As remobilization (to 31% and 27% in PP1 and U43, respectively). Sequential extraction with Tukey HSD tests showed that Fe/TBC and HA@Fe/TBC treatments notably increased stable As fraction. But the retention efficacy in PP1 decreased to 65% after the addition of humic acid (HA@Fe/TBC). Microbial enumeration indicated enhanced culturable bacterial abundance in Fe/TBC-amended soils, indicating reduced As bioavailability. Conversely, the addition of HA suppressed microbial activity in U43 soil. These findings highlight Fe/TBC as a robust amendment for As immobilization, while also underscoring the potential context-dependent risks associated with organic additives such as HA, particularly in clay-rich soils.

This study examines the activity levels and transfer factors of polonium (²¹⁰Po) and lead (²¹⁰Pb) in epiphytic plants from the coastal area of Karnataka, India. The activity levels of ²¹⁰Po and ²¹⁰Pb ranged from 1.66 to 10.6 Bq kg^-1 and 3.91-15.82 Bq kg^-1in soil, 1.71-3.75 Bq kg^-1 and 3.86-7.35 Bq kg^-1in mango trunk. Honeysuckle mistletoe showed wider variations in activity levels with 2.32-20.09 Bq kg^-1and 6.01-26.47 Bq kg^-1 for ²¹⁰Po and ²¹⁰Pb respectively. Mosses exhibited the highest activity levels for²¹⁰Po and ²¹⁰Pb with respective ranges 45.44-219.59 Bq kg^-1and 111.52-306.74 Bq kg^-1. The transfer factor of ²¹⁰Po and ²¹⁰Pb from soil to some epiphytic plants has been determined in various locations. The results have shown higher transfer factor for²¹⁰Po and ²¹⁰Pb for moss with range of 13.21-100.33 and 17.33-72.50 than honeysuckle mistletoe with a range of 1.36-7.25 and 0.82-6.87. The activity values, transfer factors, the ratio of ²¹⁰Po and ²¹⁰Pb, along with the Average Annual Committed Effective Dose values for both mango trunk and honeysuckle mistletoe samples have been computed. The estimated cancer mortality and morbidity risks ranged from ${10}^{-5}$ to ${10}^{-6}$ . A strong and statistically confirmed correlation between soil and vegetation sample activity concentrations was observed. The work quantifies radionuclide activity concentrations in vegetation samples and assesses the resulting internal radiation dose to humans through dietary intake. This research offers significant insights into the environmental interactions of these elements and highlights the potential of epiphytic plants as an effective bio-indicators for evaluating radioactive contamination in coastal ecosystems.

Urban dust serves both as a sink for heavy metals and a secondary source, yet its vertical distribution and source composition remain insufficiently explored. This study investigated the concentrations of heavy metals in rooftop and ground dust samples collected during April-September 2021 in Haidian District, Beijing. Using Inductively Coupled Plasma Mass Spectrometry (ICP-MS) and receptor models (PCA and APCS-MLR), we analyzed the spatial variation, pollution levels, ecological risks, and source apportionment of eight heavy metals (V, Cr, Ni, Cu, Zn, As, Cd, Pb). The results indicated that rooftop dust exhibited generally higher concentrations and ecological risks, with Cd identified as the most critical pollutant. APCS-MLR analysis revealed that rooftop dust was predominantly influenced by an unidentified source (67.4%), whereas ground dust was mainly affected by combustion sources (42.4%) and traffic emissions (18.2%). This vertical heterogeneity suggests that rooftop dust primarily reflects regional atmospheric deposition, while ground dust captures local pollution signals. The human health risk assessment results indicated that except for Cd, the health risks from other metals were not significant, with their risk levels being relatively low. These findings underscore the necessity for three-dimensional environmental monitoring and targeted pollution control strategies in urban areas.

Alginate-based composites have been widely studied for heavy metal removal. However, systematic exploration of the synergistic effects between pre-chemically modified biochar and the alginate matrix to enhance adsorption performance remains insufficient. This gap limits the rational design of high-performance adsorbents. To address this gap, this study developed composite gel beads (PBS-SA) based on sulfuric acid-modified pine cone biochar (PBS) and sodium alginate for the efficient removal of Cd²⁺ from aqueous solutions. The material was characterized using a series of techniques, including SEM-EDS, BET, FTIR, XRD, and XPS. The characterization revealed that PBS-SA possesses a stable three-dimensional network structure, with significantly enhanced chelating sites due to the introduced sulfur-containing and carboxyl functional groups. The adsorption behavior followed the pseudo-second order kinetic model (R² = 0.999) and the Langmuir isotherm model (R² = 0.995). The Langmuir model predicted a maximum adsorption capacity (Q_m) of 143.75 mg/g。 The primary adsorption mechanisms involved were ion exchange, complexation, precipitation, and electrostatic attraction. PBS-SA exhibited strong interference resistance in real water bodies, demonstrating good tolerance to monovalent ion interference. Its unique spherical macroscopic morphology effectively addressed the issue of powder adsorbent loss, maintaining high adsorption performance after six regeneration cycles. Furthermore, excellent continuous-flow removal efficiency was achieved in fixed-bed column experiments. This study develops a mechanically stable and reusable adsorbent capable of enhancing Cd removal through the combination of multiple mechanisms, providing a practical strategy for treating heavy metal-contaminated water.

The impact of mining activities in the Krajište area (southeastern Serbia) on the pollution status of rivers and lakes as well as the associated environmental and health risks were assessed. For river and stream water, at sites close to mining and ore processing operations, high concentrations of Pb (up to 2125 μg L^-1), Cd (up to 22.9 μg L^-1) and As (up to 137 μg L^-1), along with high values of heavy metal pollution index (up to 3897) were observed. In the assessment of health risks, hazard index values above the threshold of 1 were obtained for Pb (up to 76), Cd (up to 12), and As (up to 23). Results of the sequential extraction showed that the most mobile elements in the sediments are Mn and Pb, followed by Cu, Zn and Cd, while the least mobile are Co, Ni, Cr, Al, Fe and As. The distribution of the content of these elements by fractions, comparison of total content with standards and with the results of similar studies worldwide show that mining has a negative impact on the quality of the investigated surface waters and sediments. The observed pollution poses a significant problem for the surface water environment and for the health of people living in the area. These results underscore the need for remediation measures and continuous monitoring in mining-impacted river basins.