Journal of Environmental Science and Health Part A-toxic\/hazardous Substances & Environmental Engineering最新文献

Toxic metals are persistent environmental pollutants with significant ecological and health risks due to their non-biodegradability and bioaccumulation. This study assessed the extent of toxic metal pollution and associated ecological and human health risks in soils and stream sediments of Idanre area, Southwest Nigeria. Forty samples (20 soils, 20 sediments) were analyzed using X-ray fluorescence for major oxides and trace metals. Multivariate statistical methods and geochemical indices were used to determine contamination levels and sources. Human health risks were evaluated using United States Environmental Protection Agency (USEPA) models for ingestion, inhalation, and dermal exposure. Results showed SiO₂ dominance in soils and sediments, indicating silicate-rich parent material. Elevated concentrations of Pb (24.59-82.19 mg/kg), Cd (0.63-1.96 mg/kg), and Cr (30-93.35 mg/kg) exceeded background levels, pointing to anthropogenic sources. Stream sediments showed higher contamination, especially Zn (avg. CF = 7.59), Cd (3.89), and Pb (3.98). Igeo values confirmed moderate to strong enrichment, and Cd posed moderate to high ecological risk (Er = 71.82-174.55). Health risk assessments indicated significant non-carcinogenic risks in children (HI = 4.88-9.66), mainly via dermal exposure and ingestion, with Pb, Cr, and Co as key contributors. Adults showed negligible risk, and carcinogenic risks remained within acceptable limits, with Cr as the main carcinogen.

Global textile production, driven by consumer demand, raises significant concerns about exposure to chemicals in clothing and related products. This review synthesizes evidence (2019-2025) on hazardous substances in textiles, including dyes, plasticizers, per- and polyfluoroalkyl substances (PFAS), and metals, and identifies and categorizes their associated human health risks. Emerging evidence highlights microfibers as critical vectors for chemical exposure via inhalation and dermal routes, necessitating updated risk assessments. Focusing on dermal absorption as the primary exposure route, risks to vulnerable populations (e.g., infants, pregnant women) and gaps in regulatory frameworks are highlighted. The current analysis reveals that chronic exposure to chemical mixtures in textiles remains poorly understood, with current safety assessments often neglecting synergistic effects. Key findings include elevated risks from phthalates in infant clothing, PFAS in water-repellent fabrics, and carcinogenic aromatic amines (AAs) from azo dyes. We underscore the urgency of harmonized global regulations, advanced biomonitoring, and sustainable alternatives (e.g., enzymatic dyes, biodegradable finishes). Public awareness initiatives and stricter enforcement of certifications like OEKO-TEX^® or GOTS are critical to mitigating risks. Interdisciplinary collaboration among textile technologists, toxicologists, and public health experts is essential to develop safer textile alternatives and integrate health-centric approaches into sustainability agendas, safeguarding consumers, workers, and ecosystems.

This study evaluated the toxicological and mutagenic potential of water samples from a Wastewater Treatment Plant (WWTP) in Lavras, Minas Gerais, Brazil. Samples were taken from four sites: upstream in the stream (P1), downstream (P2), at the entrance of the treatment station (P3), and at the exit (P4). We conducted physicochemical analyses in water, phytotoxicity tests on plants (Triticum aestivum, Pennisetum glaucum, Lactuca sativa, Raphanus sativus), cytogenotoxicity tests using onion roots (Allium cepa), and Artemia salina immobilization tests. Elevated Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD), anionic surfactants, and ammoniacal nitrogen were found at P3 and P4. While germination rates were generally unaffected, P4 inhibited the germination speed of R. sativus. The growth of L. sativa increased in P3 and P4, and of R. sativus in P2, due to more nitrogen and phosphorus. T. aestivum and P. glaucum, however, had their growth inhibited at P4 due to surfactant toxicity. Cytogenotoxicity tests revealed the highest frequencies of micronuclei and nuclear buds in cells exposed to P3 and P4. Additionally, P3 caused 87.5% immobilization of A. salina. These findings suggest that the WWTP is not fully efficient, and its effluent discharge may contribute to eutrophication and genetic mutations in exposed organisms.

Activated carbon derived from avocado seeds (AVSAC) was evaluated for its ability to adsorb and desorb Thorium(IV) ions, targeting applications in nuclear waste management and environmental cleanup. Extensive characterization (FTIR, XRD, SEM, TGA/DSC, BET) confirmed structural changes upon Th(IV) uptake; notably, FTIR indicated hydroxyl and aromatic groups participate in binding, while SEM and BET showed significantly reduced porosity and surface area, consistent with effective adsorption. At pH 3.0, a fixed-bed column (0.50 g AVSAC; flow rate 0.25 mL min^-1; residence time 4 min mL^-1) treated 50 mL of 750 mg L^-1 Th(IV), achieving 97.3% removal (36.5 mg captured; 73 mg g^-1 working capacity). The adsorption was remarkably fast, sequestering 94% of Th(IV) within five minutes. Kinetic data fit a pseudo-second-order model well, and equilibrium data aligned with the Freundlich isotherm, consistent with PSO behavior on a heterogeneous surface; overall uptake is predominantly physical (thermodynamics/D-R), with localized Th-O coordination contributions. Thermodynamic analysis revealed a spontaneous and endothermic process. Regeneration studies showed that 1.00 M nitric acid could recover 70.5% of the adsorbed thorium. Overall, this work highlights AVSAC as a highly promising, efficient, and regenerable adsorbent for removing Th(IV) from aqueous solutions, offering valuable insights for treating contaminated water streams.

Mercury (Hg) contamination in soil is a serious environmental and health concern due to its high toxicity and bioaccumulation. This study investigated the potential of rice husk biochar (RHB), bamboo biochar (BB) and tyre-modified biochar (T-RHB and T-BB) for mitigating Hg contamination. Biochar was produced through pyrolysis of agricultural residues at 500-550 °C and characterized for surface area, elemental composition, functional groups using BET, CHNS, FTIR and SEM-EDS analysis. The results showed that Hg removal followed a chemical adsorption process. Tyre-modified biochar was more effective in removing Hg, with T-BB and T-RHB adsorbing 82.64 mg/g and 47.62 mg/g of Hg, which was much higher than the unmodified BB (38.46 mg/g) and RHB (32.36 mg/g). The Langmuir model indicated monolayer adsorption with higher Q_max and K_L values, showing stronger Hg binding on modified biochar. TCLP tests revealed that tyre-modified biochar reduced Hg leaching by 85% (T-BB) and 72% (T-RHB) compared to untreated soil. Even under different pH conditions, the modified biochar maintained high Hg-binding efficiency, especially near neutral to slightly alkaline conditions (pH 7.3-9.6). Overall, tyre-modified biochar offers a cost-effective, eco-friendly and sustainable way to stabilize Hg in contaminated soil while turning waste tyre powder and agricultural residues into useful materials.

Microplastics (MPs) are emerging environmental contaminants that pose significant risks to ecosystems and human health. Traditional detection methods for microplastics in water and other matrices often involve complex and costly techniques. In this research, we introduce an innovative approach utilizing carbon quantum dots (CQDs), a class of fluorescent nanomaterials known for their simple synthesis, low cost, eco-friendliness, and low toxicity. MPs were successfully stained with CQDs by optimizing the reaction conditions through a microwave-assisted synthesis. The resulting MP-CQD composites were characterized using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), profilometry, and UV-Vis analysis. This study further investigated the fluorescence emission from CQD-stained MPs and examined the impact of MP concentration on particle agglomeration. This novel method demonstrated the ability to effectively agglomerate and detect MPs at very low concentrations, offering a streamlined and efficient approach to MPs detection in water. The optimized method enabled visible fluorescence detection of MPs at concentrations as low as 0.005 ppm, demonstrating sensitivity comparable to instrumental approaches but with greater simplicity and accessibility. The integration of CQDs into this process marks a significant advancement in detecting and potentially removing MPs from aquatic environments.

Polyvinyl alcohol (PVA) wastewater was pretreated by iron-carbon (Fe/C) microelectrolysis. The effects of initial pH, reaction time, aeration volume, and iron-carbon dosing on chemical oxygen demand (COD) removal rate were investigated. The COD removal rate is used as the response function and the response surface method (RSM) is optimized. When the initial pH was 1.8, the reaction time was 2.5h, the aeration volume was 4.3 L/min, and the treatment concentration was 800 mg/L of polyvinyl alcohol wastewater, the COD removal rate was the highest, 62.26%, and the PVA removal rate reached 64.88%. Among them, reaction time and aeration volume are key factors in improving the treatment effect. Research shows that after pretreated PVA wastewater is treated by a microelectrolytic reactor, the organic pollutants in the wastewater can be basically completely degraded or converted, and the biochemical properties of the wastewater can be improved.

Mining-induced heavy metal pollution poses an urgent ecological challenge. Recently, biochar, especially corn stover biochar (CSB) modified with ionic liquids (ILs) for weak interactions, has shown promise in mine water remediation. In this study, we used charred corn stover as biochar and synthesized 1-methyl-3-[3-(trimethoxysilyl) propyl] imidazolium IL as modifier to create imidazolium-based IL-modified biochar. The chemical structure of the IL and the chemical composition of the biochar were analyzed with the help of ¹H NMR and FT-IR. Characterization techniques such as XPS, SEM, and nitrogen adsorption-desorption measurements were employed to investigate the elemental composition, surface morphology, pore size, porosity, and other physicochemical properties of the corn straw biochar. Cd²⁺ was chosen as the representative of heavy metal ions in mine water, and the adsorption kinetics and isotherm experiments were conducted to study the adsorption performance of CSB on heavy metal ions. The results exhibited that the adsorption performance of IL-modified CSB material (Q_e = 48.1000 mg/g) for heavy metals was enhanced to a certain extent compared with that of unmodified CSB material (Q_e = 44.0000 mg/g). This provided a foundation for using corn straw biochar to remove heavy metals in mine water.

Wastewater from pharmaceutical industries has made pharma industries as one of the major emerging pollutants. In this study, physicochemical parameters were evaluated, and potentially toxic elements (PTEs) were analyzed by ICP-AES. LC-MS revealed the presence of various organic pollutants including antibiotics (Levofloxacin, Kanamycin, Streptothricin F), anticancer drugs, β-blockers, hormones, NSAIDs, psychiatric drugs, and CNS stimulators, among other PPCPs. The cyto-genotoxic potential of wastewater was evaluated using Allium cepa chromosomal aberration assay. Toxicity was measured through mitotic index and chromosomal aberration after treatment with different concentrations (v/v) of wastewater. Significant increase in chromosomal abnormalities and decrease in mitotic index with increasing concentration of effluent was observed. The lowest MI was recorded (7%) at 100% concentration of wastewater. Furthermore, to assess phytotoxicity Vigna radiata seed germination assay was performed and found that the number of seeds germinated and other parameters such as seedling vigor index, radical and plumule length significantly decreased when treated with different concentrations of wastewater. Oxidative stress was shown in Vigna radiata root by Confocal Laser Scanning Microscope. This study highlights the toxicological risk posed by pharmaceutical wastewater due the presence of various PPCPs and PTEs which might be toxic and adversely affect human health, plants as well as environment.

Chronic Kidney Disease of unknown etiology (CKDu) is a major public health concern in the North Central Province (NCP) of Sri Lanka, where groundwater heavy metal contamination is suspected as a key contributing factor. This study investigates the mobilization and transport of in-situ heavy metals in agricultural soils from Medawachchiya and Horowpathana and examines the movement of artificially introduced Cadmium and Lead through soil column experiments. Four locally available, low-cost bio-adsorbents namely, Mahogany sawdust (MG-A), Jackfruit peels (JF-A), Rice husk (RH-A), and Coconut husk (CH-A) were evaluated for Cd²⁺ removal from synthetic groundwater. Among them, MG-A demonstrated the highest adsorption efficiency (73.12% for 80 mg/L and 92.2% for 10 mg/L), outperforming JF-A (60.07%), RH-A (36.73%), and CH-A (16.54%). Adsorbent characterization using FTIR, FE-SEM, and BET analyses revealed that surface functionality and porosity played key roles in adsorption performance. Regeneration studies showed that acid (HCl) treatment restored the adsorption capacity of MG-A by 91.49%, indicating strong reusability potential. The novelty of this research lies in integrating soil transport experiments with bio-waste-derived adsorbent development, providing a comprehensive understanding of heavy metal mobility and remediation. These findings demonstrate a sustainable, community-adaptable approach for mitigating Cd²⁺ contamination in groundwater, offering practical and scalable solutions to reduce CKDu risks in vulnerable regions.