Search Results (439)

In 2023, Murcia implemented a new sustainable urban Mobility Plan emphasizing pedestrianization, segregated public transportation, and the reduction of private vehicle traffic within the city. Consequently, this study aimed to evaluate heavy metal pollution in urban dust by comparing data collected prior to the plan’s implementation (2016) with that obtained afterward (2025). Systematic sampling of urban dust was conducted at 84 sites during both study periods. The concentrations of elements were quantified employing inductively coupled plasma mass spectrometry. The K-means algorithm was employed to identify data clusters. The analysis revealed a distinct geochemical shift, with the dominant elemental abundance changing from Fe > Zn > Mn > Pb > Cu > Cr in 2016 to Fe > Zn > Mn > Cu > Cr > Pb by 2025. Concentrations of Pb and Mn declined following the implementation of the Mobility Plan, whereas levels of As exhibited an increase between 2016 and 2025. Children are at risk of exposure arising from As, which was identified as the contaminant of greatest concern. The Murcia Mobility Plan, implemented in 2023, had a significant and multifaceted impact. It led to a decrease in traditional metal contaminants and simultaneously highlighted the emergence of new contaminants, such as arsenic (As). Full article

High-sensitivity detection of metal contaminants during gas-insulated equipment (GIE) manufacturing is crucial to mitigating insulation risks. In this study, detection tests of metal contaminants are performed using the conventional partial discharge measurement (CPDM), UHF, and photon counting (PC) methods on a 252 kV GIS chamber. The results indicate that the PC method exhibits high sensitivity to micrometer-sized metal dust, while the UHF sensor performs better in detecting the millimeter-sized single wire-shaped particle. The CPDM method has no sensitivity advantage in either of the above cases. For sub-millimeter-sized block contaminants, all three methods exhibit comparable sensitivity. Moreover, a comprehensive statistical index is introduced to evaluate the discharge activity of different metal defects, enabling a more robust quantitative comparison. Full article

Ambient exposure to fine particulate matter (PM_2.5) remains a critical global public health concern; however, the speciation and bioaccessibility mechanisms of particle-bound heavy metals within the lung environment are still insufficiently understood. In particular, the role of soluble and insoluble metal species in simulated lung fluids requires further clarification. Road dust, a major contributor to PM_2.5, contains heavy metals that pose significant inhalation risks, leading to oxidative stress, DNA damage, and systemic toxicity. This study investigated the contamination characteristics, bioaccessibility, pollution level, and speciation of heavy metals in PM_2.5-fractionated road dust (PM_2.5RD) collected from Karachi (a megacity with >27 million inhabitants) and Shikarpur (a medium-sized city of ~0.3 million) in Pakistan. A grid-based sampling approach was applied across four functional zones (residential, school, hospital, and office), yielding 48 samples. Inhalation bioaccessibility was evaluated using artificial lysosomal fluid (ALF; pH 4.5, 37 °C, 24 h), revealing moderate bioaccessibility of Cr, As, and Pb. Pollution status was assessed using contamination factor (CF), integrated pollution index (IPI), pollution load index (PLI), and potential ecological risk index. Geochemical modeling with PHREEQC 3.0 and Visual MINTEQ 3.1 was employed to simulate metal speciation, release behavior, and mineral saturation states. Overall, this study provides mechanistic insights into speciation-driven toxicity of As, Pb, and Cr in simulated lung environments, offering a scientific basis for improved risk assessment and regulatory strategies for PM_2.5-associated metal exposure. Full article

This study explores the potential of integrating agro-wastes with bamboo biochar to develop optimized substrates for cultivating Lentinus squarrosulus, aiming to enhance mycelial growth, productivity, nutritional quality, and economic returns. The chemical characterization revealed clear contrasts between sawdust and corn dust, where sawdust provided a carbon-rich but nitrogen-limited structure, while corn dust offered a greater nutrient availability. When formulated into mixed substrates, particularly at a 50:50 ratio, a more balanced physicochemical profile was achieved, improving substrate suitability for fungal growth. The incorporation of biochar (1–10%) further enhanced substrate performance by improving porosity, nutrient retention, and pH stability. Among treatments, mixed substrates supplemented with 5–10% biochar exhibited the highest mycelial growth rates and dense colonization, significantly reducing contamination rates. These conditions facilitated production cycles, with earlier primordia formation and harvesting compared to single-substrate systems. Yield performance was markedly improved in mixed formulations, especially those containing 1–5% biochar, which produced the highest fruiting body numbers, weights, and total yields. Biological efficiency exceeded 99% in optimal treatments, indicating highly efficient substrate conversion. Nutritional analysis demonstrated that substrate composition also influenced mushroom quality, with corn dust enhancing protein content, while mixed substrates promoted balanced fiber, carbohydrate, and energy profiles. Economic evaluation confirmed that integrating agro-wastes with moderate biochar levels significantly increased profitability, with the 50:50 sawdust–corn dust formulation supplemented with 5% biochar yielding the highest returns. Overall, this study highlights that strategic substrate design, balancing lignocellulosic structure, nutrient availability, and physicochemical properties, can substantially improve mushroom productivity and economic viability. Full article

Antimicrobial resistance is a critical global challenge that necessitates the development of durable, material-based strategies to limit pathogen survival and transmission. Conventional cleaning and disinfection methods only provide transient protection due to rapid surface re-contamination. This study investigates the fabrication of polyethylene terephthalate (PET) surfaces designed for antibacterial applications via femtosecond laser-induced micro- and nanostructuring. Surface texturing was performed using a Ti:sapphire femtosecond laser (wavelength λ = 800 nm, pulse duration τ = 70 fs) at peak laser fluences (F) of 2.04 J/cm² and 4.08 J/cm², generating hierarchical surface textures with controlled morphology, spacing, and geometry through ultrafast, non-contact laser processing while preserving the bulk properties of PET. The resulting patterns, including parallel and intersecting microchannels decorated with laser-induced nanostructures, enabled tunable surface roughness and wettability, with water contact angles ranging from 33.21° to 118.2°. Comprehensive surface characterization, including morphological, topographical, and wettability analyses, was performed to establish structure–property relationships associated with previously reported antibacterial surface design principles. However, direct antibacterial performance was not evaluated in the present study and will be the subject of future investigations. In addition, the durability of the laser-structured PET was evaluated under simulated real-life conditions, including thermal cycling, ultraviolet exposure, abrasion, chemical resistance, and dust contamination. The structured surfaces demonstrated high structural and functional stability following environmental testing. The results indicate that the laser-induced surface modifications remain stable under conditions representative of prolonged practical use, supporting their potential long-term applicability for antibacterial and self-cleaning PET surfaces. Full article

Soils developing in ultramafic (serpentinite) provinces are naturally enriched in Mg, Ni and Cr, which makes it difficult to separate the natural geochemical background from technogenic contamination near chrysotile asbestos mining operations. This problem is examined for the agricultural soils in the impact zone of the Zhitikara chrysotile asbestos quarry (Kostanay Region, Kazakhstan), one of the largest such operations in the world. The elemental composition of the soils was characterised by portable X-ray fluorescence, verified against ICP-OES, and complemented by X-ray diffraction. When contamination was assessed against the global crustal background (upper continental crust), nickel and chromium appeared enriched; however, relative to the local geochemical background, these elements fall within the natural lithogenic range, showing that global crustal values generate false-positive contamination signals in ultramafic terrains. Magnesium was the only element enriched above the local background and the only one that decreased systematically with distance from the quarry, identifying it as the most sensitive tracer of aerogenic serpentinite dust among the elements measured. The discordance between total and acid-soluble chromium is consistent with chromium being hosted mainly in a refractory chromite phase, so that total chromium contents overestimate the environmentally relevant fraction. The study demonstrates the pitfall of applying global crustal backgrounds in ultramafic provinces and supports a locally referenced, differentiated approach to soil-contamination assessment in such settings. Full article

Organophosphate esters (OPEs), extensively employed as flame retardants and plasticizers, have emerged as ubiquitous contaminants in indoor environments following the phase-out of brominated flame retardants. However, the occurrence patterns, source characteristics, and exposure implications of emerging OPE congeners across diverse urban indoor microenvironments remain inadequately elucidated. In this study, twenty-eight OPE congeners were quantified in settled dust collected from eight representative indoor microenvironments and one outdoor reference site in Beijing, China. Total OPE concentrations exhibited pronounced spatial heterogeneity, ranging from 8.46 to 42.60 mg kg⁻¹, with the highest levels observed in subway stations and laboratories. Non-halogenated OPEs dominated the contamination profile, accounting for 80.7% of the total OPEs, whereas Tris(2-ethylhexyl) phosphate (TEHP), 2-Ethylhexyl diphenyl phosphate (EHDPP), Tris(1-chloro-2-propyl) phosphate (TCIPP), Tris(2-chloroethyl) phosphate (TCEP), and Triphenyl phosphate (TPhP) collectively contributed 85.1% of the overall burden. Correlation analysis and positive matrix factorization revealed that indoor OPE contamination was primarily associated with emissions from building materials, polymer-containing consumer products, furniture, and electronic equipment. Transformation-associated compounds such as Bis(2-butoxyethyl) hydroxyethyl phosphate (BBOEHEP) were detected in indoor dust, pointing to the plausible presence of OPE transformation processes in such enclosed settings. Exposure assessment demonstrated that dust ingestion accounted for over 98% of total OPE intake, resulting in substantially higher exposure levels in children than in adults. Although estimated non-carcinogenic and carcinogenic risks remained below established health-based thresholds, exposure was disproportionately driven by a limited number of congeners, particularly EHDPP, TCIPP, TCEP, and TEHP. These findings highlight the growing contribution of replacement OPEs to indoor chemical burdens and underscore the importance of incorporating transformation products and indoor aging processes into future exposure and risk assessments frameworks. Full article

The [O ii] $\lambda 3727$ emission line is a widely used star formation rate (SFR) tracer. However, its application to type I quasars is not straightforward, because the line can be affected by dust extinction, metallicity and contamination from the AGN narrow-line region (NLR). We test the reliability of [O ii] SFRs using a sample of 202 SDSS and PG quasars, by comparing [O ii] SFRs and reference far-infrared (FIR) SFRs derived from multiwavelength SED decomposition. We measure [O ii], [O iii], and narrow Balmer emission lines by spectral fitting. Then, we calculate [O ii] SFRs after correcting dust extinction and metallicity. We then compare these SFRs with the FIR SFRs, both with and without subtracting the AGN contribution estimated from [O iii]. After this correction, the median offset between [O ii] and FIR SFRs is $-0.20\pm 0.72$ dex for the full analysis sample and $-0.17\pm 0.69$ dex for sources with S/N $>5$ in both [O ii] and [O iii]. Without subtracting the AGN contribution, the corresponding offsets are $0.00\pm 0.69$ and $0.12\pm 0.66$ dex. We conclude that [O ii] is useful as a statistical SFR tracer for quasar host galaxies, but individual objects still require careful treatment of AGN contamination, extinction, metallicity, aperture effects, and redshift-dependent systematics. Full article

Background: Produced by indoor Stachybotrys and Trichoderma spp., macrocyclic trichothecenes (MTs), a type of cytotoxic respirable molecule (<0.01–0.03 µm), inhibit protein/DNA/RNA production, damage mitochondria, and induce apoptosis. Dust-bound MTs remain toxic despite remediation/disinfection. Inhaled MTs easily cross tissue barriers, potentially reaching the placenta and the unborn. Methods: Retrospective medical record abstraction of pregnant females and offspring cohort exposed to indoor MTs, Stachybotrys, or Trichoderma to correlate professional indoor testing, exposure variables, mold species, environmental MTs, medical symptomatology, outcomes, and urine/milk MTs excretion. Results: In eight women from seven MT/mold-contaminated homes, with 21 pregnancies, complications occurred in 19 (90%) pregnancies, including miscarriages (38%) and premature labor (33%). Placental abnormalities in two women (25%) from the same home (calcification, chronic villitis, placental infarcts, double placenta, gritty membranitis). Birth defects in infants (38%) included renal hypertrophy, levocardia, patent foramen ovale, ventriculoseptal defect, ptosis, teeth, and “goosebump” black/grey skin discoloration. Later abnormalities included developmental delay, oropharyngeal hypotonic dysphagia, refractory eczema, and refractory perirectal rash progressing to intussusception. Lactation difficulties included grey-black oronasal drainage, thrush, projectile vomiting, choking, oropharyngeal neurologic damage, apnea, and respiratory arrest. Aspergillus +/− Penicillium exposure was documented in all, Stachybotrys (75%), Chaetomium (62%), Trichoderma (38%), and indoor MT contamination exposure (75%). Conclusions: In-utero indoor MTs and Stachybotrys exposure correlate strongly with adverse gestational, neonatal complications (miscarriage, congenital defects, and placental abnormalities). Exposure timing and severity correlate with adverse outcomes. Breastfeeding with indoor exposure appears hazardous. Environmental/human MTs testing appears useful for identifying MT contaminaion and/or exposure. Full article

Heavy metal contamination in urban street dust is often highly heterogeneous, limiting the effectiveness of conventional geostatistical mapping approaches. In Mexico City, previous studies have reported very low spatial autocorrelation for key elements, making interpolation-based methods unsuitable for representing contamination patterns. This study proposes a multiscale cartographic framework to analyze and visualize heavy metal contamination in street dust from 482 sampling sites using the contamination factor (CF) and pollution load index (PLI) at three levels of spatial analysis: (i) city-scale patterns identified through hierarchical clustering of districts based on median CF values, (ii) district-scale variability assessed through statistical comparisons of PLI distributions, and (iii) site-scale identification of contamination hotspots using observed PLI values. Results revealed five contamination clusters and significant differences in pollution load among districts (Kruskal–Wallis, p < 0.05); PLI values in Xochimilco and Tláhuac are significantly lower than in Cuauhtémoc, Gustavo A. Madero, and Magdalena Contreras. Higher contamination levels were concentrated in northern and central districts, whereas lower levels predominated in the south. Site-scale analysis identified localized hotspots associated with transportation infrastructure, industrial areas, and commercial corridors, reflecting the influence of local emission sources. The results demonstrate that contamination patterns operate simultaneously at city, district, and site scales and cannot be adequately represented through interpolation alone. The proposed framework provides a practical approach for visualizing heterogeneous contamination datasets, supporting environmental decision-making, and may apply to other metropolitan regions characterized by weak spatial autocorrelation and localized pollution processes. Full article

Surface dust samples were collected from bus stops and parking lots in different functional areas of Binzhou City, Shandong Province, China. This study investigated the contamination characteristics, source apportionment, and potential ecological and health risks of potentially toxic elements (PTEs) in these dust samples. Eight target PTEs, including As, Zn, Pb, Cu, Cd, Cr, Ni, and Mn, were quantitatively analyzed. The results revealed distinct concentration differences in these elements between bus stop dust and parking lot dust. Several PTEs exceeded the corresponding local soil background values, predominantly Zn, Pb, Cu, Cd and Cr. Principal component analysis (PCA) indicated that Zn, Pb, Cu, Cr, Ni, and Mn in bus stop dust were mainly sourced from traffic emissions, whereas As and Cd primarily originated from atmospheric deposition. For parking lot dust, Zn, Pb, Cu, Cd, Cr, and Mn were predominantly attributed to traffic sources, while As and Ni were mainly derived from natural background sources. The geo-accumulation index (I_geo) demonstrated that As, Cr, Ni, and Mn had negligible environmental impact, Pb, Cu, and Cd induced slight pollution, and Zn resulted in moderate pollution. Except for Cd, the average individual potential ecological risk index ($E_r^i$) values for all elements were below 40, suggesting a low ecological risk. Cd posed a moderate ecological hazard, whereas the comprehensive ecological risk index ($E_r^i$) values of all analyzed elements were at an extremely low level. The hazard index (HI) values via different exposure pathways and for all PTEs in both bus stops and parking lots were lower than 1, indicating no significant non-carcinogenic health risk. The carcinogenic risk ranking of elements was Cr > Cd > Ni > As, and their carcinogenic risk values (CR) via inhalation exposure were below 1 × 10⁻⁶, indicating no carcinogenic risk. This study provides a scientific basis for the environmental quality control and risk management of surface dust in urban bus stops and parking lots. Full article

Informal electronic-waste (e-waste) dismantling can mobilize mercury (Hg) from Hg-containing components and contaminated dust, while local diet can contribute methylmercury (MeHg), creating a mixed environmental exposure setting for human biomonitoring. This pilot study integrated paired biomarkers, local foods, work and indoor dust, Hg speciation and hair Hg isotope signatures among 18 e-waste dismantling workers in Qingyuan, South China. Total Hg (THg), MeHg and inorganic Hg (IHg) were measured in hair, blood and foods; urine and dust were analyzed for THg; and hair δ²⁰²Hg, Δ¹⁹⁹Hg and Δ²⁰¹Hg were determined. Median THg was 403 μg/kg in hair, 1.60 μg/L in blood and 0.438 μg/L in urine. Fish showed the highest food THg, whereas work and indoor dust had the highest matrix concentrations. Hair was MeHg-dominant but contained substantial IHg, and Δ¹⁹⁹Hg values were positive but modest. The integrated patterns support mixed dietary MeHg and non-dietary IHg contributions and identify exposure-pathway priorities for future biomonitoring and source-focused studies. Full article

Road dust is an important urban reservoir of potentially toxic elements (PTEs) and a relevant source of human exposure through resuspension and inhalation, particularly in large megacities. This study provides an integrated assessment of the seasonal variability, contamination levels, source identification, particle characteristics, lung bioaccessibility, and health risk of road dust in Mexico City, one of the world’s largest urban centers. A total of 74 road dust samples were collected during the dry and wet seasons, and V, Cr, Mn, Co, Ni, Cu, As, Cd, Sb, and Pb were analyzed by ICP–MS in the <20 µm fraction. Geochemical indices, spatial analysis, Pearson correlation, principal component analysis, SEM–EDS particle characterization, in vitro lung bioaccessibility (ALF), and human health risk models were applied. Sb, Cu, and Pb were identified as the most enriched elements, exceeded local background concentrations at all sampling sites. Spatial patterns revealed recurrent hotspots in the northern, northeastern, and central sectors of the city. SEM–EDS analyses showed that most particles belonged to the 2.5–5 µm equivalent-size class and included Fe-rich spherules, Pb-rich aggregates, silicate grains, and C-rich particles. Health risk assessment indicated acceptable risks for adults, whereas children exceeded the non-carcinogenic threshold (HI = 3.85–4.60) and slightly surpassed the upper acceptable carcinogenic risk level. Lung bioaccessibility results revealed low Pb solubility but high mobility of Ni and Cu, with some samples reaching complete dissolution under ALF conditions. These findings demonstrate that traffic-derived road dust represents a persistent urban exposure pathway in Mexico City and highlight the importance of integrating total concentrations, particle characteristics, and bioaccessibility data to improve environmental and health-risk assessments in urban environments. Full article

In situ leaching (ISL) is the most popular method for uranium mining worldwide, particularly in arid and semi-arid regions. Despite its economic benefits, ISL raises concerns about radioactive migration and groundwater contamination. This review assesses the environmental impacts of ISL uranium mining, focusing on radionuclide transport pathways and key information gaps. This review, focusing on groundwater contamination, radionuclide migration, soil and sediment contamination, atmospheric impacts, vegetation responses, and ecosystem disturbances, summarizes current understanding of the hydrogeochemical, radiological, and environmental impacts of uranium mining. The analysis indicates that groundwater is the environmental component most vulnerable to contamination during ISL operations due to the injection of acidic or alkaline leaching solutions that may mobilize uranium, radium, sulfates, selenium, arsenic, and other potentially hazardous elements. In addition to impacts on groundwater, there have also been reports of soil contamination, airborne dust, radioactive accumulation in flora, and impacts on aquatic and microbiological resources, particularly in arid and semi-arid regions. Although cleanup methods and natural attenuation can minimize contamination to some extent, residual contamination can persist for decades after mine closure. Overall, ISL uranium mining emphasizes the need for effective groundwater management, long-term environmental monitoring, and improved reclamation methods, balancing surface disturbance with long-term hydrogeochemical and environmental concerns. Full article

The risk of exposure to mycotoxins in livestock farming is still poorly characterized, particularly in Italy where human biomonitoring data are scarce. Livestock farms represent a high-risk setting due to frequent handling of contaminated feed and dust-generating activities. This pilot study applied a human biomonitoring approach to assess internal exposure to multiple mycotoxins among pig farmers in Southern Italy. Urinary biomarkers of aflatoxin B1 (AFB1), aflatoxin M1 (AFM1), ochratoxin A (OTA), and fumonisin B1 (FB1), together with oxidative stress biomarkers (8-oxo-7,8-dihydroguanine (8-oxoGua), 8-oxo-7,8-dihydro-2′-deoxyguanosine (8-oxodGuo), 8-oxo-7,8-dihydroguanosine (8-oxoGuo), 3-nitrotyrosine (3-NO₂Tyr), and 5-methylcytidine (5-MeCyt)), were measured in urine samples from 35 workers and 30 non-exposed controls. A sensitive and validated HPLC–MS/MS multi-mycotoxin method was developed and applied. Biomonitoring results were also discussed in relation to previous environmental monitoring. AFM1 emerged as the most frequently detected biomarker in the exposed group, with concentrations above the limit of detection (LOD) in 22.8% of samples; 11.4% exceeded the limit of quantification (LOQ). In contrast, only 10% of the control samples had values above the LOD and none exceeded the LOQ, suggesting a possible contribution linked to occupational tasks. This study provides original biomonitoring evidence of low-dose, mixed mycotoxin exposure among Italian swine farmers and highlights the value of integrating environmental and biological monitoring to improve occupational exposure assessment in livestock production systems. Full article