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PubMed2026

Stable chloroform emissions in southeastern China: insights from recent observations.

Chloroform (CHCl3) is a short-lived ozone-depleting substance not currently regulated under the Montreal Protocol. Due to the unique meteorological conditions in East Asia, CHCl3 emitted in this region has a greater potential to reach the stratosphere and contribute to ozone depletion. As an essential component of national CHCl3 emissions, southeastern China has attracted increasing attention. However, long-term observational data in this region remain relatively scarce, with no updates since 2020. In this study, we continuously measured atmospheric CHCl3 concentrations at a remote monitoring station in southeastern China from 1 June 2023 to 31 May 2025. Frequent concentration enhancements were observed during the monitoring period, with mixing ratios ranging from 9.3 to 134.1 ppt and an average value of 36.8 ± 19.7 ppt. Back-trajectory analysis indicated that air masses associated with elevated CHCl3 levels primarily originated from coastal industrial provinces in eastern China. Using the Potential Source Contribution Function and Concentration Weighted Trajectory methods, we identified the Yangtze River Delta (Jiangsu, Anhui, and Zhejiang Provinces) and Jiangxi Province as dominant source regions. Emissions of CHCl3 in southeastern China were estimated using the Tracer Ratio Method to be approximately 30.1 ± 5.3 Gg/yr from 2023-06-01 to 2025-05-31, indicating overall stability relative to earlier estimates and no apparent upward trend. These findings provide updated insights into the current status of CHCl3 emissions in southeastern China and highlight the need for continued monitoring and emission assessment of CHCl3 in East Asia, given its unregulated status and implications for ozone layer recovery.

Air Pollutants↗

PubMed2026

Prenatal exposure to particulate matter (PM) and autism spectrum disorder (ASD) among children: a systematic review and meta-analysis.

The global surge in Autism Spectrum Disorder (ASD) cases, coupled with evidence linking prenatal Particulate Matter (PM) exposure to developmental disruption, demands a comprehensive review to design targeted health interventions. This systematic review and meta-analysis aim to evaluate the strength and consistency of evidence linking prenatal PM exposure to ASD across studies, quantifying this relation to identify actionable environmental risk thresholds. This study employed PRISMA protocols to systematically extract and evaluate evidence from PubMed, Web of Science, Scopus, and ScienceDirect (2010-2024), and screened 4,013 articles to identify qualified case-control and cohort studies (n=29). Data synthesis employed random-effects modeling, accompanied by comprehensive assessment through I2 statistics, Q-tests, funnel plots, Duval and Tweedie's trim-and-fill analysis, and Egger's regression, to ensure validity. A meta-analysis of 16 case-control studies revealed a 34 % increased risk of ASD associated with prenatal PM exposure (pooled OR=1.34; 95 % CI: 1.13-1.54), despite substantial between-study heterogeneity (I2=94.02 %, p<0.001). Publication bias was not significant (Egger's test p value=0.114). Critical trimester-specific analysis uncovered that third-trimester exposure significantly increased ASD risk (OR=1.17; 95 % CI: 1.01-1.34), while first-trimester (OR=1.02; 95 % CI: 0.92-1.11; I2=49.18 %, p<0.10) and second-trimester exposures (OR=1.13; 95 % CI: 0.88-1.38; I2=92.59 %, p<0.001) showed non-significant associations. This review identified prenatal and early life exposure to PM as a risk factor for ASD, indicating a trimester-specific vulnerability. It highlighted the necessity of focused air quality interventions and targeted guidance to reduce prenatal PM exposure to alleviate ASD risk during the critical-window.

Child↗

PubMed2026

Electron shuttles facilitate methane-dependent arsenate reduction in paddy soils.

Methane-dependent arsenate reduction (M-AsR) occurs widely in paddy soils and can substantially enhance arsenic mobilization, posing potential ecological risks. However, the role of electron shuttles in this process remains poorly understood. In this study, we investigated the influence of anthraquinone-2,6-disulfonate (AQDS) on M-AsR in paddy soils. Fourteen-day incubation showed that 1 mmol/L AQDS facilitated 50.88 % of arsenate reduction and 31.31 % of methane oxidation. Quantitative polymerase chain reaction analysis revealed that AQDS significantly increased the abundance of functional genes associated with arsenate reduction (arrA, arsC) and anaerobic methane oxidation (mcrA) (P < 0.05). Microbial community analysis revealed that AQDS addition enriched Cloacibacterium, Sphingorhabdus, and Methylocystis, while decreasing the relative abundance of Methylobacter and Methylomonas. These findings indicate that electron shuttles facilitate M-AsR by modulating functional microbial populations, providing valuable insights into arsenic biogeochemistry and the coupled cycling of methane and arsenic in paddy soils.

Methane↗

PubMed2026

Maternal transfer of nonylphenol drives oxidative, immune, and epigenetic dysregulation in zebrafish offspring.

Nonylphenol (NP), a widespread surfactant and endocrine-disrupting pollutant, poses significant ecological and public health risks globally; however, its transgenerational effects remain poorly understood. Using zebrafish (Danio rerio), we compared chronic maternal NP exposure (50 and 100 µg/L, 28 days) with acute embryonic exposure (0.22 µmol/L) during 0-3 days post-fertilization (dpf) to delineate mechanistic differences in toxicity. Maternal NP exposure produced severe developmental defects in offspring, including edema, axial curvature, impaired swim bladder inflation, reduced growth, cardiac dysfunction, and decreased viability. These phenotypes were accompanied by systemic molecular disruptions including oxidative stress, altered estrogen receptor (ER) expression, dysregulated mitogen-activated protein kinase (MAPK) signaling, and suppressed innate immune response characterized by attenuated neutrophil/macrophage density, reduced CD68 and complement protein C3 expression, diminished nitrite load, and downregulation of pro-inflammatory mediators at both transcript and protein levels. Maternal exposure further induced apoptosis and persistent epigenetic reprogramming (alterations in DNA methylation and histone-modifying enzymes), hallmarks of transgenerational toxicity. In contrast, direct embryonic NP exposure elicited morphological abnormalities without significant lethality, accompanied by induction of pro-inflammatory cytokines, nitric oxide (NO) synthesis, and MAPK activation, reflecting an augmented inflammatory response. These mechanistic contrasts reveal that maternal NP exposure is a potent driver of systemic, heritable molecular reprogramming, whereas embryonic exposure triggers acute inflammatory pathways. Together, our findings underscore the global relevance of NP as a transgenerational toxicant, advocating for its urgent inclusion in ecotoxicological risk assessments and regulatory frameworks.

Animals↗

PubMed2026

Environmentally relevant concentrations of DCOIT impaired lifespan and healthspan in Caenorhabditis elegans.

DCOIT (4,5-dichloro-2-n-octyl-4-isothiazolin-3-one) is an antifouling biocide widely used as an alternative to organotin compounds. While previous studies had focused on its effects on energy production, endocrine disruption, and lipid metabolism, its impact on aging and underlying mechanisms remained unclear. Here, we demonstrated that environmentally relevant concentrations of DCOIT (37, 370 and 3700 ng/L) significantly impaired both lifespan and healthspan in Caenorhabditis elegans. RNA-seq and validation assays revealed that DCOIT upregulated comt-4, a key gene in dopamine metabolism, leading to dopamine depletion and subsequent induction of oxidative stress. This redox imbalance critically contributed to accelerated aging phenotypes. Importantly, both genetic (comt-4 RNAi) and pharmacological (opicapone) interventions restored dopamine levels, alleviated oxidative stress, and reversed DCOIT-induced aging deficits. Our study established the comt-4/dopamine/oxidative stress axis as a central mechanism in DCOIT toxicity, suggesting dopamine modulation as a potential countermeasure against environmental toxicant-induced aging.

Animals↗

PubMed2025

Detoxifying biotransformation of chloramphenicol by Exiguobacterium sp. CAP4 and its bioaugmentation of chloramphenicol biodegradation in simulated wastewater.

The extensive use of chloramphenicol (CAP) in livestock leads the accumulation of CAP in livestock manures, threatening environmental and human health. Therefore, eliminating or reducing CAP concentration in manures before its re-utilization and application through microbial remediation is necessary. Exiguobacterium sp. CAP4, isolated from the plastisphere in duck manures, was capable of degrading CAP with the biodegradation efficiency of 97.8 % at initial CAP concentration of 5 mg/L within 4 days. A total of twenty-four biotransformation products were determined, including two novel transformation products, TP166 and TP203, enriched the integrity of CAP biodegradation pathways. Furthermore, the biotransformation process was proposed as a detoxifying process through biotransformation products toxicity evaluation. Notably, Exiguobacterium sp. CAP4 successfully colonized in the cow manures after inoculation, and bioaugmented the biodegradation of CAP in virgin cow manures. This study significantly extended our understanding of the CAP biotransformation fate, and provided a promising bacterial strain for bioremediation of CAP containing wastewater in situ.

Chloramphenicol↗

PubMed2026

The global potential of freshwater microbes for plastic degradation.

Plastic pollution is becoming increasingly severe on a global scale, and the potential for biodegradation as a treatment method that is environmentally friendly merits greater attention. A significant number of genes that associated the degradation of plastic (PDAGs) have been identified, however, the distribution of these genes among microorganisms in global inland waters remains to be elucidated. A global-scale meta-analysis was conducted, incorporating approximately 1000 metagenome datasets of inland waters across seven continents. A total of 13,109 metagenome-assembled genomes (MAGs) were obtained by means of metagenomics binning, and 22,621 PDAGs were identified from these. Among these recognized PDAGs, phenylacetaldehyde dehydrogenase (PAD) was the most dominant (n = 16,664), followed by catalase (n = 5931). The predominant hosts for PAD and catalase were identified as Gamma-proteobacteria and Bacteroidia, respectively. The largest number of both PAD and catalase was found in MAGs from North America, while the average gene number in single MAG was highest in MAGs from Oceania. In accordance with the prediction of traits, PDAG-carrying MAGs from Europe demonstrated the fastest growth rate and the lowest optimal growth rate. Furthermore, 25 styrene monooxygenase (StyA) enzymes were identified, which were found to cluster into two distinct groups hosted by Alpha-proteobacteria and Gamma-proteobacteria, respectively. Moreover, 11 MAGs were observed to possess the complete pathway of polystyrene degradation. These results explored the potential of inland water microorganisms as a biological resource for plastic degradation and provided valuable microbial reference information that can be used to develop biological treatment technologies for mitigating plastics.

Plastics↗

PubMed2026

Health risk assessment of inorganic arsenic: an umbrella review.

Inorganic arsenic (iAs) is a toxic environmental pollutant linked to serious health risks, prompting global regulatory efforts. This study identifies major health conditions associated with iAs exposure using text network analysis, and assesses health risk assessments through an umbrella review and dose-response analysis. It synthesizes previous systematic reviews to offer a broader perspective on iAs-related health effects. An optimized text network analysis-based search strategy was applied across multiple databases to identify relevant systematic reviews. An umbrella review framework was employed to synthesize and reinterpret findings across systematic reviews. The methodological quality of included systematic reviews was assessed using the A MeaSurement Tool to Assess systematic Reviews 2 tool. Extracted data on study characteristics, exposure levels, and risk estimates were analyzed to evaluate the dose-response relationship between iAs exposure and health outcomes. From 922 systematic reviews, 36 were included and categorized into 10 health condition groups. For example, seven SRs found a significant dose-response relationship between iAs and bladder cancer, with one systematic review reporting relative risks of 2.70, 4.20, and 5.80 at 10, 50, and 150 µg/L, respectively. Individual study analysis further showed that each 10 µg/L increase in iAs raised bladder cancer risk by 3.11 % (p=0.003). iAs exposure is associated with hypertension, diabetes, cardiovascular disease, and adverse fetal outcomes. Dose-dependent increases in bladder cancer, lung cancer, and hypertension risks were observed. These findings support more precise health risk assessments and regulatory strategies.

Humans↗

PubMed2026

A novel urease-producing strain effectively induces cadmium biomineralization under low-temperature stress.

Microbially induced carbonate precipitation (MICP) has been widely used to immobilize Cadmium (Cd) in contaminated soils in mining-affected regions. However, its remediation efficacy under low-temperature stress, as well as the nucleation process that regulates Cd biomineralization via carbonate precipitation by psychrophilic bacteria, has yet to be investigated. Here, we isolated Pseudomonas sp. J-6, a novel urease-producing strain from tailings in high-altitude cold regions, exhibiting unparalleled cold adaptability at 5 °C and achieving 95.85 % Cd removal efficiency by MICP at 10 °C. Furthermore, the coprecipitation process of Ca1-xCdxCO3 was clarified through the continuous observation of the precipitates after the low-temperature MICP reaction. The crystal morphology transitioned from loose vaterite in the early stage to a dense square-block morphology in the middle stage. Cd2+ progressively shifted from a surface-bound state to lattice incorporation, ultimately resulting in the formation of stable Cd-substituted calcite crystals. In this process, low temperatures led to the formation of larger, highly ordered Cd-substituted calcite crystals, thereby strengthening Cd sequestration and its long-term stability. In addition, under low-temperature stress, Pseudomonas sp. J-6 induced MICP reaction decreased the bioavailable Cd in alpine slag soil by 44.85 % and enhanced physical properties. In the freeze-thaw cycles, the remediation efficiency remained stable. This study clarified the biomineralization potential in high-altitude cryogenic environments and the nucleation process of Cd biomineralization by psychrophilic bacteria-induced carbonate precipitation, filling a critical research gap in its application under extreme conditions and highlighting its promise for sustainable remediation of heavy metal pollution under low-temperature stress.

Cadmium↗

PubMed2026

Thermal analysis techniques for microplastic mass quantification: Methodological challenges and standardization needs.

Microplastics (MPs, 1 μm-5 mm) and nanoplastics (NPs, <1 μm) are ubiquitous contaminants requiring standardized quantification methods. This systematic review evaluates thermal analysis techniques for mass-based MP detection, including pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS), thermogravimetry-MS (TGA-MS), thermal extraction desorption-GC-MS (TED-GC-MS), and differential scanning calorimetry (DSC). Database searches (Web of Science, from inception to December 1, 2025) following PRISMA guidelines identified studies across seven environmental matrices (water, soil/sediment, atmosphere, biota, human tissues). We identify critical standardization gaps: inconsistent marker ion selection, unvalidated conversion factors for tire and road wear particles (TRWPs), and the absence of certified reference materials for complex matrices. Py-GC-MS demonstrates versatility but suffers from lipid interference in biological samples; TED-GC-MS offers superior sensitivity (sample capacity ∼200× Py-GC-MS) but lacks real-time chromatographic monitoring. To advance data comparability, we propose: (i) harmonized ion selection hierarchies based on specificity-sensitivity balance, (ii) matrix-specific TRWP quantification protocols, and (iii) inter-laboratory validation using environmental reference materials. This review provides a methodological roadmap for standardizing thermal analysis in MP research.

Humans↗

PubMed2026

Identification and formation pathways of oxidation products of chlorinated paraffins during ozonation in municipal wastewater.

Chlorinated paraffins (CPs) cannot be efficiently removed by conventional water treatment processes and are continually discharged into the aqueous environment. Ozonation can effectively remove lipophilic and persistent pollutants. However, the degradation behaviors of short-chain CPs (SCCPs), medium-chain CPs (MCCPs), and long-chain CPs (LCCPs) in wastewater during the ozonation process remained unknown. In this study, ozonation treatment achieved removal efficiencies of 61 % for SCCPs, 66 % for MCCPs, and 51 % for LCCPs from wastewater within 30 min. Approximately 147 oxidative products of SCCPs, MCCPs, and LCCPs were non-targeted identified through Ph4PCl-enhanced ionization with ultra-high performance liquid chromatography-Orbitrap mass spectrometry. These oxidation products were structurally classified into three categories: carbon chain breakage (53 products), HCl-elimination (27 products), and hydroxylation (67 products). Twenty-three di-hydroxylated CPs were newly identified among the products. Hydroxylation was the predominant pathway for SCCPs, producing di-hydroxylated SCCPs ((OH)₂-SCCPs) with a higher generation rate constant (KG = 22.28 × 10⁻² min⁻¹) compared to other products. MCCPs and LCCPs mainly underwent carbon chain breakage and hydroxylation, generating shorter carbon chain congeners, (OH)2-SCCPs, and di-hydroxylated MCCPs ((OH)2-MCCPs). The KG values of (OH)2-SCCPs (10.56 × 10-2 min-1) and (OH)2-MCCPs (12.05 × 10-2 min-1) generated from the MCCPs were the highest, and the KG values of MCCPs (6.49 × 10-2 min-1), SCCPs (6.27 × 10-2 min-1), and (OH)2-SCCPs (4.74 × 10-2 min-1) generated from the LCCPs were higher than those of other products. These results comprehensively clarify the oxidation efficiencies and pathways of CPs during ozonation. Future studies must explore the potential risks associated with the oxidation products.

Water Pollutants, Chemical↗

PubMed2026

Three-dimensional porous nano-hydroxyapatite@gelatin composite as efficient adsorbent for uranyl ion removal from low-level radioactive wastewater.

The contamination of water resources by uranyl (UO22+) ions poses significant environmental and health risks, requiring the development of efficient and sustainable remediation strategies. Adsorption-based techniques have emerged as promising approaches in the field of UO22+ removal, but the design of cost-effective, high-capacity, and environmentally friendly adsorbents remains challenging. In this study, a three-dimensional porous nano-hydroxyapatite@gelatin (nHAP@Ge) composite was synthesized through glutaraldehyde cross-linking, combining the structural stability of Ge with the high uranium affinity of nHAP. The optimized nHAP@Ge, with a nHAP:Ge mass ratio of 1:0.5, exhibited exceptional UO22+ removal efficiency (97 %), along with high adsorption capacity (364.03 mg/g). Systematic characterizations using scanning electron microscopy (SEM), thermogravimetric analysis (TGA), Fourier transform infrared (FT-IR) spectroscopy, and X-ray photoelectron spectroscopy (XPS) methods revealed that the porous structure and surface functional groups (-OH, Ca2+, and PO43-) of the material synergistically contributed to binding UO22+ species. Furthermore, the incorporation of nHAP into the Ge framework resulted in enhanced thermal stability while significantly improving the UO22+ adsorption performance. This work presents a scalable, eco-friendly, and recyclable strategy for the effective treatment of uranium-contaminated water, with potential applications in nuclear wastewater treatment and environmental remediation.

Adsorption↗

PubMed2025

Uncovering parental exposure risks of TCPP: Impaired development and metabolic homeostasis in zebrafish offspring.

As brominated flame retardants are phased out, tris (1‑chloro-2-propyl) phosphate (TCPP), a phosphorus-based flame retardant, has emerged as a prominent detectable flame retardant in the environment. However, TCPP has been found to exhibit endocrine-disrupting effects on organisms, raising significant safety concerns. In our study, we utilized the zebrafish model to explore the toxic effects of parental TCPP exposure on offspring and uncover its regulatory mechanisms through metabolomics analysis. Moreover, the impact on the nervous system and lipid metabolism was examined through behavioral analysis and specific staining. Our findings demonstrated that both embryonic and parental TCPP exposure induced developmental disorders in larvae, along with decreased locomotor activity and disordered lipid metabolism homeostasis. Parental exposure to TCPP, exhibiting stronger developmental toxicity than direct embryonic exposure, notably led to reductions in crucial energy substrates such as amino acids and carbohydrates. Meanwhile, embryonic TCPP exposure primarily affected the endogenous lipid-related metabolites including phospholipids, lipid-soluble vitamins, steroids and fatty acids, promoting lipid accumulation in larval liver and subcutaneous tissue. What's more, continuously parental and embryonic exposure showed the most pronounced effects on zebrafish development and metabolic regulation. Our study highlights the risk posed by parental exposure to TCPP on offspring zebrafish, underscoring the need for comprehensive consideration of the impact from parental exposure in pollutants regulation.

Animals↗

PubMed2026

Urban stormwater infrastructure as a microplastic superhighway: a critical review of transport dynamics, modelling, and mitigation across pavements and drainage networks.

This review examines the transport, fate, modelling, and mitigation of Microplastics (MPs) in urban stormwater infrastructure, with emphasis on pavements, runoff pathways, micro-drainage, and macro-drainage systems. Following a systematic review approach, more than 1000 records were screened and approximately 50 core studies were retained when they addressed urban stormwater or drainage-related MP transport with adequate methodological reporting; marine-only studies and biological-effect studies without direct relevance to transport processes were excluded. The evidence shows that stormwater systems function not merely as passive conduits but as dynamic reactive transport systems with temporary storage, where particle mobilisation, sedimentation, resuspension, and temporary retention regulate MP export. Road surfaces, especially high-traffic areas, are major reservoirs of tyre wear, road-marking, atmospheric, and litter-derived particles that are rapidly mobilised during rainfall. Conventional grab sampling may underestimate MP loads, which in some cases exceed treated wastewater effluent loads by up to six-fold. Drainage structures such as manholes can immobilise up to 17.3% of near-neutrally buoyant particles, while biofouling and aggregation may shift buoyant polymers from wash-load to bedload. Mitigation systems, including permeable pavements, bioretention, wetlands, and technical inserts, can achieve high removal of coarse MPs, but performance declines for fine particles below 100 µm. The review highlights the need for standardised flow-proportional sampling, physically informed modelling, and treatment-train strategies targeting both surface sources and in-network storage.

Microplastics↗

PubMed2026

Influence of microplastics on microalgal performance during wastewater polishing.

Microplastics (MPs) are emerging contaminants that are increasingly accumulating in aquatic ecosystems due to excessive anthropogenic activity and insufficient mitigation strategies, posing serious environmental and public health risks. Their impact on wastewater (WW) treatment processes remains poorly understood. This study evaluated the effects of five MPs commonly found in WW - polypropylene, polystyrene, polyamide, low-density polyethylene, and high-density polyethylene - on the physiology and bioremediation performance of the microalga Chlorella vulgaris in synthetic WW (SWW). Metabolic responses were assessed via esterase activity and intracellular reactive oxygen species (ROS), while nitrogen (N), phosphorus (P), and glucose removal were monitored to evaluate bioremediation efficiency. MPs inhibited esterase activity and elevated ROS levels, indicating oxidative stress. Nevertheless, C. vulgaris maintained a high bioremediation capacity (> 75 % N, > 60 % P, and > 70 % for glucose). Environmental conditions modulated microalga response to MPs exposure. Under N-limited conditions, C. vulgaris exhibited enhanced nutrient uptake and biomass production, but a 12 h/12 h light/dark photoperiod reduced N removal but stimulated glucose consumption via heterotrophic metabolism. In contrast, C-limited conditions exacerbated oxidative stress and compromised nutrient removal, resulting in residual concentrations exceeding legal limits. These findings highlight that environmental factors can either mitigate or exacerbate the physiological stress induced by MPs, ultimately affecting WW polishing. This work provides a comprehensive insight into the cellular and metabolic effects of MPs on microalgae and supports C. vulgaris as a resilient and sustainable approach for nutrient and carbon removal in MP-contaminated WW systems.

Microalgae↗

PubMed2026

Marine air promotes structural compaction and coating growth of soot aerosols after long-range transport from East Asia.

Soot aerosol, a key global warming contributor, undergoes morphological and chemical transformations during atmospheric transport, particularly in humidified marine environments. This study investigates morphology, mixing state, and aging mechanisms of soot particles collected in the Bohai Sea and Yellow Sea. Transmission electron microscopy analyses reveal that coated soot particles dominate the marine atmosphere, accounting for over 98 % of soot-containing particles, with a mean mixing state index (χ) of 0.83. The fractal dimension (Df) of soot particles is 1.84 ± 0.05 in the Northern Yellow Sea, 1.90 ± 0.08 in the Bohai Sea, and 1.96 ± 0.07 in the Southern Yellow Sea, indicating structural compaction during long-range transport. Correspondingly, the average Dp/Dcore ratios (particle to core size ratio) are 5.3 in the Bohai Sea, 4.2 in the Northern Yellow Sea, and 3.9 in the Southern Yellow Sea. Notably, those ratios are higher in marine environments compared to those observed during continental regional transport from northern to southern China (3.54), suggesting enhanced coating growth in humid marine air. The results highlight the important role of marine atmospheres in accelerating soot aging, which in turn leads to significantly stronger light absorption compared to soot in continental air. Our results highlight the necessity of incorporating compact morphologies, uniform mixing states, and thick coatings into optical models for accurate radiative forcing simulations.

Aerosols↗

PubMed2026

Comparison of black carbon measurements using filter-specific reference transmittance to those using lab blanks or an average of unloaded filters.

Filter-based optical techniques compare light transmission intensities between loaded (I) and unloaded (I0) filters as a measure of light-absorbing mass for subsequent estimations of equivalent black carbon (eBC). We analyzed 5,379 15 mm Teflon filters from the Household Air Pollution Intervention Network (HAPIN) trial to assess the influence that different methods of I0 estimations have on eBC measures. We compared eBC measurements using filter-specific I0 values (Method 1) to those using three other methods of I0 estimation: the lab blank scan from a given session (Method 2), the average of all pre-sample filter scans (Method 3), and the average of all lab blank filter scans (Method 4). We assessed the agreement between Method 1 and the alternative methods using Bland-Altman analysis. We also assessed the relationship between Method 1 and the alternative methods across the complete measurement range and after stratifying exposure data into quartiles according to Method 1 eBC exposures. The mean (SD) personal eBC exposure for Method 1 was 7.8 μg/m3 (5.9), and exposures ranged from 1.3 to 46.8 μg/m3. Compared to Method 1, eBC using Methods 2, 3, and 4 were higher by 0.7 μg/m3, 0.1 μg/m3, and 0.7 μg/m3, respectively. The performances of linear regression models between Method 1 and all other methods were moderate to strong (R2 range: 0.42-0.93) in the second, third, and fourth quartiles; however, the models in the first quartile (eBC range: 1.3-2.9 μg/m3) performed poorly (R2 = 0.25-0.26), with error approximately 25% of the mean. Our findings suggest that, in most instances, conventional methods for obtaining I0 values can be used to sufficiently characterize eBC; however, analyzing filters before sampling adds appreciably to the accuracy of eBC estimations in lower concentration settings.Implications: Filter-based optical techniques compare light transmission intensities between loaded (I) and unloaded (I0) filters as a measure of light-absorbing mass for subsequent estimations of equivalent black carbon (eBC). To assess the influence that different methods of I0 estimations have on eBC measures, we analyzed 5,379 15 mm Teflon filters from the Household Air Pollution Intervention Network (HAPIN) trial. Our findings suggest that, in most instances, conventional methods for obtaining I0 values can be used to sufficiently characterize eBC; however, analyzing filters before sampling adds appreciably to the accuracy of eBC estimations in lower concentration settings.

Soot↗

PubMed2026

Towards microplastic bioremediation: Fungal degradation of pristine and pretreated high-density polyethylene and polystyrene.

Microplastic (MP) contamination has become a significant ecological issue because of its enduring existence in the ecosystem and its possible negative impacts. Therefore, using degrading strategies to eliminate these stubborn polymers has been a subject of scientific research. However, the currently used degradation methods are relatively inefficient. Given the pervasiveness of High-Density Polyethylene (HDPE) and Polystyrene (PS) and their resistance to biodegradability, disposal strategies are critical and must be addressed. This manuscript examines the biodegradation of pristine and UV-treated HDPE and PS MPs by Aspergillus flavus species in minimal growth media over 70 days. The maximum weight loss observed at 70 days for pristine HDPE and PS in sole carbon source (SCS) media was (29.33 ± 0.28) % and (17.67 ± 0.35) %, respectively. Whereas, for UV-treated HDPE and PS MPs, the % weight reduction was (33 ± 0.21) % and (25 ± 0.19) %, respectively. UV-treated MPs exhibited greater weight reduction, as UV induced oxygenated functional groups enhance polymer susceptibility to enzymes, thereby promoting biodegradation. HDPE MPs typically show a higher proportion of particles in the lower size range compared to PS MPs. This assertion was based on the weight loss, particle size distribution, and SEM analysis. Furthermore, chemical changes were evaluated using Fourier transform Infrared Spectroscopy (FTIR) analysis, which also displayed chemical oxidation occurring during biodegradation. Liquid Chromatography-Mass Spectrometry (LC-MS) results indicate that UV pretreatment enhances biodegradability by promoting chain scission. These findings further suggest that this fungus's natural and ubiquitous occurrence in terrestrial and marine environments may actively contribute to MP biodegradation while requiring few nutrients.

Microplastics↗