Environmental Geochemistry and Health最新文献

The study examined natural radionuclide levels in edible muscles of cephalopod species consumed in Kerala. Uranium (²³⁸U) concentrations ranged from 1.14 ± 0.06 to 1.72 ± 0.07 Bq kg^-1, while thorium (²³²Th) levels were between 0.08 ± 0.02 and 0.66 ± 0.04 Bq kg^-1. Polonium (²¹⁰Po) showed higher concentrations, ranging from 4.7 ± 0.9 to 27.2 ± 3.3 Bq kg^-1, and lead (²¹⁰Pb) levels varied from 3.8 ± 0.9 to 24.6 ± 6.8 Bq kg^-1. Squids, being pelagic, accumulated higher amounts of ²³⁸U and ²¹⁰Po, whereas cuttlefishes, being benthic, showed greater levels of ²³²Th and ²¹⁰Pb. Statistical analysis revealed significant differences in radionuclide concentrations among and within cephalopod species, influenced by habitat and taxonomy (p < 0.05). The annual committed effective dose (ACED) for coastal residents consuming these cephalopods was assessed. ²¹⁰Po was the main contributor to radiation dose, comprising over 80% of the total dose from all radioisotopes analyzed. Despite this significant contribution, the study concluded that health risks from consuming these cephalopods were within acceptable safety limits.

Fenitrothion (FNT) is a widely used organophosphorus pesticide with low toxicity to humans and animals. Due to its wide application in agriculture, the distribution and toxic effects of FNT have received increasing attention. This review comprehensively assesses environmental levels and human exposure to FNT. FNT can be absorbed into the human body through various routes, including ingestion, dermal contact, and inhalation. Humans are exposed primarily through their diet. It has been shown in previous studies that FNT has several toxic effects, such as neurotoxicity, endocrine disruption, hepatotoxicity, immunotoxicity, reproductive toxicity, and developmental toxicity. FNT also induces oxidative stress, apoptosis, and inflammatory responses, which are crucial mechanisms underlying its multiple toxicities. This review will help to fill the gaps in knowledge related to the exposure, toxicity, and toxicity mechanisms of FNT and provide a scientific and theoretical basis for the environmental management of FNT.

The unchecked consumption of antibiotics leads to the persistence of their active form residues in the environment, perpetuating the cycle of exposure, selection and re-infection, which ultimately exacerbates the environmental antimicrobial resistance (AMR). This work aims to provide a direct comparison of different heterogeneous and underutilised biomass as antibiotic adsorbents. This study investigates the adsorption of the antibiotic, specifically Ciprofloxacin (CIP), by biochars produced from two underutilised biomass sources-unsorted Garden waste (GW) and Cashew nut shells (CNS)-at different temperatures (500-700 °C) and residence times (1-2 h). Based on initial adsorption screening and thermogravimetry, GW biochar, produced at 700 °C with a 2-h residence time (GW700 °C/2 h), was selected as the most suitable. A detailed analysis of this biochar was carried out: TGA confirmed the thermal stability; proximate analysis confirmed a high fixed carbon content; BET analysis (59.11 m² g ¹), FTIR, and XRD indicated the presence of relevant functional groups, and FE-SEM displayed a porous surface morphology, all of which substantiate the adsorption performance. Furthermore, optimum sorption conditions were determined through batch studies, and 50 mg GW700 °C/2 h biochar was found to remove 85.4% of 5 mg L^-1 CIP in 285 min at a neutral pH. Kinetic and isotherm data confirmed multilayer chemisorption with a maximum sorption capacity of 6.19 mg g^-1. This is the first report exploring unsorted GW biochar as a sustainable solution for antibiotic mitigation, which, in future, can be scaled up to be part of the wastewater treatment systems.

In this work, we investigate anatase-phase TiO₂ nanoparticles as efficient photocatalysts for degrading Reactive Violet 5 (RV5) under natural sunlight exposure. The photocatalytic performance was optimized by studying the effects of pH, catalyst loading, and dye concentration. Under ideal conditions (30 mg of TiO₂, 10 mg/L RV5, pH 5.4), up to 96% degradation of RV5 was achieved within 120 min. Structural characterization revealed that the nanoparticles possess a porous and granular morphology, contributing to enhanced light absorption and active surface sites. Mechanistic insights point to hydroxyl radicals (·OH) and superoxide species (·O₂⁻) as the dominant reactive intermediates driving the degradation process. Beyond pollutant remediation, the synthesized TiO₂ nanoparticles exhibited significant anticancer effects. In vitro cytotoxicity assays against MCF-7 cancer cell lines demonstrated a dose-dependent reduction in cell viability, with IC₅₀ values of 8.96 µg/mL, respectively. The therapeutic action is attributed to intracellular ROS generation, leading to oxidative stress-induced apoptosis. These findings underscore the multifunctional potential of anatase TiO₂ nanoparticles as sustainable agents for environmental detoxification. Additionally, TiO₂ nanoparticles demonstrate effective cancer cell suppression, reinforcing their relevance in advanced nanotechnology applications.

Microplastics (MPs) ubiquitously contaminate ecosystems and serve as efficient vectors for heavy metals (HMs), amplifying their environmental mobility and bioavailability. Although the individual toxicological impacts of MPs and HMs are well-documented, their combined effects, driven by complex adsorption dynamics and synergistic toxicity, remain poorly understood. This review systematically synthesizes recent advances in MP-HM interactions, with a focus on adsorption mechanisms such as electrostatic attraction, biofilm facilitation, and co-precipitation. Key factors governing adsorption efficiency, including polymer crystallinity, environmental aging, biofilm formation, and water chemistry, are critically examined. Furthermore, we elucidate the compounded toxicity of MP-HM complexes across aquatic and terrestrial organisms, manifesting as oxidative stress, multi-organ damage, and endocrine disruption, with bioaccumulation risks that propagate through food chains to humans. By identifying critical knowledge gaps, particularly regarding long-term ecotoxicological outcomes and transgenerational effects, this review provides a mechanistic framework to guide future research and evidence-based policy for mitigating composite pollution in a rapidly changing environment.

Autoimmune diseases (ADs) are a heterogeneous group of disorders characterized by loss of immune tolerance against self-antigens, leading to local or systemic inflammation and subsequent tissue/organ damage. Until now, the etiology of ADs remains obscure. Growing evidence suggests that microplastics (MPs) may act as emerging environmental triggers in the initiation and progression of these disorders. MPs have been shown to modulate immune-related gene expression and induce excessive reactive oxygen species production in various immune cells, such as macrophages, T cells, and B cells. This may lead to the release of pro-inflammatory cytokines and could create conditions that may promote the production of autoantibodies. Moreover, MPs can activate neutrophils and natural killer cells, potentially exacerbating immune dysregulation and chronic inflammation. Additionally, plasticizers and other chemical additives in MPs interact with immune cells via nuclear and membrane receptors, suggested to cause mitochondrial dysfunction and potentially further compromise immune homeostasis. Given the increasing presence of MPs in the environment and their potential immunomodulatory effects, understanding their role in ADs is of critical importance. This review summarizes the recent evidence and unveils the potential impact of MPs on immune functions and the pathogenesis of major ADs, including systemic lupus erythematosus, rheumatoid arthritis, and inflammatory bowel disease. Furthermore, we highlight future research directions to better understand the influences of MPs on ADs.

Waste rock from coal mining in the Elk Valley, Canada primarily consists of mudstones and siltstones, and contains two natural nitrogen (N) reservoirs: organic N and exchangeable ammonium in clay minerals (NH₄⁺-ex). Although the mean concentration of organic N is greater than that of NH₄⁺-ex (713 ± 615 vs. 31.0 ± 24 mg N/kg), laboratory experiments show NH₄⁺-ex undergoes rapid (< 50 d) nitrification to nitrate (NO₃^-) while organic N is nonreactive over the time frame of the experiments (393 days). A conceptual model was developed, based on the results of batch experiments to describe the release of NH₄⁺-ex within individual mine-rock particles and its diffusion to particle surfaces where it is nitrified to NO₃^-. Oxic experiments with various parent rock particle sizes (< 0.71 to 75 mm), along with N form analyses on aged mine-rock particles (< 2 to 1000 mm; estimated to be 22 years old at the time of sampling in 2022), show NO₃^- release occurs rapidly (< 1 year) in particles less than several tens of millimetres in diameter. However, larger particles exhibit slower NO₃^- release due to delayed migration of NH₄⁺ to particle surfaces. The results show nitrification of NH₄⁺-ex can be a major contributor to the NO₃^- load to surface waters from mine-rock piles and potentially lead to prolonged NO₃^- release. Such a process may affect aquatic systems associated with other mine-rock piles. Residual ammonium nitrate used as blasting agents provide an additional source of NO₃^- and NH₄⁺ in the mined rock. Based on the current results, it is not possible to distinguish the relative contributions of NO₃^- from blasting agents and NH₄⁺-ex.

The assessment of soil and nutrient erosion along the scattered Brahmaputra River in the Jorhat district of Assam has been attempted utilizing field and laboratory assessments, satellite remote sensing techniques, and the Revised Morgan-Morgan-Finney (RMMF) soil erosion model. River portions were mapped based on visually interpreted and geo-coded false colour composites (FCC) of Landsat-9 OLI data and Survey of India toposheets (1:50,000). Soil samples were collected from 62 different sites within a region of 86.78 km² on the banks of the Jorhat River. The main findings revealed that approximately 55.24% of the study region was inundated at least once during the flood period from May to July 2023. The study area showed total sand content between 26% and 84%, silt 5%-48%, clay 6%-36% and organic matter content 0.20%-2.08%. Erodibility indices like Clay Ratio (mean 4.91), Modified Clay Ratio (mean 4.67), Dispersion ratio (mean 0.19), Erosion Ratio (mean 0.11) and Erosion Index (mean 0.20) indicated that most soils in the study area were susceptible to erosion. Using the Revised Morgan-Morgan-Finney model, annual soil loss was estimated, with runoff transport capacity ranging from 5.16 to 164.68 t ha⁻¹ (mean: 37.27 t ha⁻¹), and total annual detachment ranging from 11.56 to 129.14 t ha⁻¹ (mean: 77.59 t ha⁻¹) and transport capacity was considered as estimated soil loss as it was lower than total detachment. Pearson's correlation matrix shows that aggregate stability had negative association with sand fraction and positive associations (p <  = 0.05) with clay and organic matter. Also, hydraulic conductivity (HC), water holding capacity (WHC) and available water (AW) demonstrated negative (p <  = 0.05) associations with soil loss. The total fertile soil loss was estimated as 322,668 tons annually, with annual losses of organic carbon, total nitrogen, total phosphorus, and total potassium estimated at 1,444.32 tons, 23.52 tons, 227.15 tons, and 4,710.64 tons, respectively. Change detection (from 1986 to 2022) was estimated based on various land use patterns, where riverine sand, built-up land, cropland showed percent increase as 61.16%, 52.75% and 14.38% respectively. But, negative percent change of 73.37%, 12.72% and 32.65% were showed against Land use/land cover (LULC) classes of barren land, river/waterbodies and grassland respectively. Hence, expanding cropland and bare sand on coarse-textured, low organic matter soil drove the extreme soil and nutrient erosion in the study area. This study underscores the potentiality of combining the Revised MMF model with geospatial analysis to effectively identify and quantify soil erosion in the study area.

Heavy metals (HMs) are mostly toxic to all forms of life and are tenacious environmental pollutants. Rapid industrialization, urban development, and unsustainable agricultural implications lead to their accumulation in soil and water ecosystems, promoting serious ecological and health risks. In course of time, the growing global population, demand for food, water, energy, and technology have increased heavy metal-contaminated wastewater discharges. Conventional physicochemical treatment approaches, although widely applied, often suffer from limitations such as incomplete metal removal, significant energy requirement and cost effectiveness. Microorganisms such as bacteria, algae, and fungi demonstrate great efficiency in HM detoxification and degradation by virtue of their natural biological properties. These microorganisms have the capability to reduce toxic metal ions in their surroundings to non-toxic or fixed forms. The current review aims to critically assess the efficiency of individual bioremediation processes in microorganisms like bacteria, fungi, algae, and their combinatorial states like bacteria-algae, algae-fungi, and algae-algae consortia. A great deal of emphasis has been given to elucidate the mechanistic insights specific to consortia particularly mutualistic carbon/nutrient exchange, bioprecipitation, EPS-mediated capture, enzymatic transformation, adsorption/chelation and synergistic indirect effects. Moreover, the importance of interspecies interactions through metabolite transfer and signaling has been underlined in terms of system stability and remediation ability. Future research direction includes reactor-scale integration studies, modeling efforts, and the use of artificial intelligence/machine learning tools. Thus, engineered bacterial communities based on omics analysis can provide a basis to improve bioremediation strategies in terms of efficiency, stability, and sustainability for the remediation of HMs in wastewaters.

This study investigated the pollution level and assessed potential human health risk of trace elements in soil from Apo Mechanic Village, Gudu Market, and Goza Municipal dumpsite in Abuja, Nigeria where primitive recycling and recovery of valuable materials, open burning, dismantling, and dumping of wastes are being carried out. A total of 56 soil samples were collected from the three study sites and samples from their corresponding control sites, and analyzed for Zn, Cd, Cu, Ni, Pb, and Cr. The result showed that the element concentrations at the three study sites were significantly higher (P < 0.05) than their respective control sites, indicating the influence of waste recycling, dismantling, burning, and dumping activities at the sites. The average pollution load index (PLI) at the sites ranged from 5.80 to 37.09 indicating that the sites are highly polluted, with Cd and Pb being the highest contributors. Human health risk assessment revealed that there is a potential non-carcinogenic risk of Pb in adults and children through ingestion across the three study sites, and Pb in adults via dermal contact across the sites. There is also a non-carcinogenic risk of Cd and Ni through ingestion in children at the Apo site. Extremely high carcinogenic risk of Cr was found for both adults and children at all the three study sites, and carcinogenic risk of Cd in children at Apo and Goza sites and Pb in children at Goza site. This calls for an urgent need to enforce environmental regulations and prevention and monitoring of the crude and primitive waste dumping, dismantling, and burning activities at these sites as the investigated elements, particularly Pb, Cd, and Cr posed non-cancer and cancer health risks to workers and nearby residents.