Chemosphere最新文献

{"title":"Assessment of per- and polyfluoroalkyl substances (PFAS) in consumer food packaging","authors":"Kevin Stroski ,&nbsp;Yelena Sapozhnikova","doi":"10.1016/j.chemosphere.2026.144824","DOIUrl":"10.1016/j.chemosphere.2026.144824","url":null,"abstract":"<div><div>Per- and polyfluoroalkyl substances (PFAS) have been detected in food and food contact materials (FCMs) worldwide, causing concerns for human exposure through diet. In this study, we have developed and validated a new method for analysis of 73 PFAS from 15 different classes in paper and plastic FCMs. The method was based on methanolic extraction and liquid chromatography-mass spectrometry (LC-MS/MS) analysis and was validated at three spiking levels with five replicates per level. Acceptable recoveries and repeatability were achieved for 96–100 % of analytes between various spiking levels and food packaging materials. We further applied the validated method to test 66 paper and plastic food packaging materials that were in direct contact with the previously tested food samples of chicken, pork, beef and catfish purchased from grocery stores in the US. Nine PFAS were detected in the samples: 8:2 FTSA, 6:2 diPAP, 8:2 diPAP, diSAmPAP, PFBA, PFHxA, PFOA, PFBS and PFOS with ∑PFAS concentrations ranging from 0.11 to 16.3 ng/g. At least one PFAS was detected in 64 % of the samples. The most frequently detected PFAS was 6:2 diPAP found in 61 % of samples, across all material types in concentrations 0.09–10.3 ng/g. Results suggest no evidence of PFAS transfer from FCMs tested in this study to packaged food tested in our previous study.</div></div>","PeriodicalId":276,"journal":{"name":"Chemosphere","volume":"395 ","pages":"Article 144824"},"PeriodicalIF":8.1,"publicationDate":"2026-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145923968","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Keto-enol insecticides disrupt ovarian Wnt/armadillo signaling and redox balance, inducing generational toxicity in Drosophila melanogaster","authors":"Berenyce González Marín ,&nbsp;José Pedraza-Chaverri ,&nbsp;Omar Noel Medina-Campos ,&nbsp;Edmundo Bonilla ,&nbsp;Hilda Zamira Vilchis González ,&nbsp;Mauricio Reyes Acuña ,&nbsp;María Elena Calderón-Segura","doi":"10.1016/j.chemosphere.2025.144816","DOIUrl":"10.1016/j.chemosphere.2025.144816","url":null,"abstract":"<div><div>This study is the first to detect Wnt/armadillo signaling pathway activity in the germarium of Fz3-RFP transgenic <em>Drosophila melanogaster</em> females orally exposure to sublethal concentrations of the keto-enol insecticides Movento® 240 SC (0, 11.2, 22.4, 37.3 mg/L) and Envidor® 240 SC (0, 12.3, 24.6, 41.1 mg/L) for 72 h. Both insecticides induced irregular overexpression of receptor Fz3 in regions 1 and 2a of the germarium, accompanied by morphological changes, tissue disorganization, and reduced cell number compared to controls. In wild-type females, oxidative stress was evidenced by increased MDA (malondialdehyde) levels and elevated antioxidant enzyme activities of SOD (superoxide dismutase) and CAT (catalase) following exposure. These effects correlated with reduced fertility, reproduction, and generational alterations, assessed via oviposition and hatching rates, and larval development (L1, L2, L3). Movento® 240 SC and Envidor® 240 SC significantly increased MDA (0.32–0.78 and 0.21–0.57 nmol mg⁻¹ protein) and enzymatic activities of CAT (0.16–0.20 and 0.13–0.15 U mg⁻¹ protein) and SOD (0.40–0.69 and 0.19–0.54 U mg⁻¹ protein), respectively, compared to controls. Oviposition and hatching rates decreased to 22–62 % and 47–86 %. Larval progression from L1 to L3 was delayed, with reductions of 30–97 %. Additionally, 60 % of L1 larvae from females exposed to 22.4 and 37.3 mg/L Movento® 240 SC and 24.6 and 41.1 mg/L Envidor® 240 SC exhibited locomotor defects, including reduced head-thrust intensity, body curling, and diminished burrowing, highlighting significant generational impacts.</div></div>","PeriodicalId":276,"journal":{"name":"Chemosphere","volume":"395 ","pages":"Article 144816"},"PeriodicalIF":8.1,"publicationDate":"2026-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145903925","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hydrocarbon dynamics influenced by coal-related activities in a South Atlantic River–Estuarine System: Challenges for conventional source apportionment approaches","authors":"Ana Caroline Cabral ,&nbsp;Cristian T. Timoszczuk ,&nbsp;Fernanda T.F. do Nascimento ,&nbsp;Henrique J.R. Dias ,&nbsp;Jamile T. Nasser ,&nbsp;Jéssica M.V. de Araújo ,&nbsp;Rafael P.R. Marcelino ,&nbsp;William S.G. Brandão ,&nbsp;Sergio Antônio Netto ,&nbsp;César C. Martins","doi":"10.1016/j.chemosphere.2025.144822","DOIUrl":"10.1016/j.chemosphere.2025.144822","url":null,"abstract":"<div><div>The Tubarão River-estuarine system (TRES), located in the South Atlantic, Brazil, is essential for water supply, agriculture, fisheries, and industrial activities. It has historically been affected by coal extraction, urbanisation, and industrial discharges, activities that generate significant impacts on ecosystem health, such as decreased water quality, habitat degradation, and potential bioaccumulation of toxic compounds in aquatic organisms. Nineteen sediment samples were collected along the TRES to assess contamination levels and evaluate the sources and spatial distribution of pollution. The study encompassed both aliphatic hydrocarbons (AHs) and polycyclic aromatic hydrocarbons (PAHs). Total AH concentrations ranged from 3.86 to 69.4 μg g⁻¹ (mean: 25.7 ± 20.7 μg g⁻¹), with ΣC₁₀–C₄₀ <em>n</em>-alkanes accounting for 0.34–12.0 μg g⁻¹ (mean: 4.65 ± 4.07 μg g⁻¹). PAH levels were between 6.42 and 6440.2 ng g⁻¹ (mean: 1370.7 ± 1654.6 ng g⁻¹ for Σ₂₇PAHs, excluding retene and perylene) and 3.47 to 1540.8 ng g⁻¹ (mean: 323.4 ± 385.5 ng g⁻¹) for Σ₁₆PAHs. The TRES is strongly influenced by anthropogenic hydrocarbons, with the most prominent contamination observed in the upper reaches of the river and the Rocinha River tributary. The middle section of the system is moderately affected, likely due to dilution by tributary inputs, while the lower reaches experience consistent pollution from urban and industrial activities. Contamination pattern is potentially influenced by fine coal particles and sorbent nanoparticles derived from mining and other coal-related activities. In this context, these particles may also influence source apportionment analyses, which revealed mixed petrogenic- and pyrogenic-like signatures, consistent with the geochemical characteristics of coal-derived PAHs in coal-influenced systems. These data are crucial for monitoring long-term pollution trends, as environmental conditions and contamination levels typically change gradually, offering valuable insights for future assessments and regional policy development.</div></div>","PeriodicalId":276,"journal":{"name":"Chemosphere","volume":"394 ","pages":"Article 144822"},"PeriodicalIF":8.1,"publicationDate":"2026-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145880231","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Environmental tobacco smoke is a major contributor to lead, cadmium, and arsenic in settled house dust","authors":"Nicolas Lopez-Galvez ,&nbsp;E. Melinda Mahabee-Gittens ,&nbsp;Penelope J.E. Quintana ,&nbsp;Ashley L. Merianos ,&nbsp;Nathan G. Dodder ,&nbsp;Eunha Hoh ,&nbsp;Lara Stone ,&nbsp;Kayo Watanabe ,&nbsp;Georg E. Matt","doi":"10.1016/j.chemosphere.2025.144820","DOIUrl":"10.1016/j.chemosphere.2025.144820","url":null,"abstract":"<div><div>Tobacco smoke contains toxic chemicals, including heavy metals lead (Pb), cadmium (Cd), and arsenic (As), that are found in secondhand and thirdhand smoke, the chemical residue that lingers and accumulates in indoor environments. This study examined tobacco smoke's contribution to heavy metal accumulation in house dust after smoking stops. Dust samples were collected from 179 homes of cigarette smokers with young children and analyzed for nicotine and tobacco-specific nitrosamines (TSNAs) using isotope-dilution liquid chromatography-tandem mass spectrometry. Pb, Cd, and As were analyzed by inductively coupled plasma-mass spectrometry. Bivariate correlation and multivariable models were used to examine associations between tobacco use markers and heavy metal dust loading, controlling for sociodemographic, home, and smoking characteristics. All samples contained Pb (geometric mean: 34.2 μg/m²), Cd (0.40 μg/m²), As (1.6 μg/m²), nicotine (15.7 μg/m²), and TSNAs (6.0 ng/m²); 100 % exceeded the current EPA standard for Pb (0 μg/ft²). Metals correlated positively with nicotine (Pb: r = 0.68; Cd: r = 0.70; As: r = 0.70; all p &lt; 0.001) and TSNAs (Pb: r = 0.50; Cd: r = 0.47; As: r = 0.51; all p &lt; 0.001). Nicotine loading was strongly associated with higher loading of the other contaminants (Pb: <span><math><mrow><mover><mi>β</mi><mo>ˆ</mo></mover></mrow></math></span> = 0.68; Cd: <span><math><mrow><mover><mi>β</mi><mo>ˆ</mo></mover></mrow></math></span> = 0.71; As: <span><math><mrow><mover><mi>β</mi><mo>ˆ</mo></mover></mrow></math></span> = 0.69; TSNAs: <span><math><mrow><mover><mi>β</mi><mo>ˆ</mo></mover></mrow></math></span> = 0.83; all p &lt; 0.001). The semi-partial R² values showed that nicotine uniquely explained 43 % of Pb, 58 % of Cd, and 54 % of As dust-loading variance. Our model projected that, in a fully tobacco-free home, dust loadings of Pb, Cd, and As would decrease by 87 %, 49 %, and 38 %, respectively. This study provides compelling evidence that tobacco smoke residue is a significant yet underrecognized source of toxic metals in household dust, independent of established factors such as housing age. It substantially contributes to indoor lead, cadmium, and arsenic levels. Given children's heightened vulnerability, these findings highlight the urgency of smoke-free policies and thirdhand smoke remediation.</div></div>","PeriodicalId":276,"journal":{"name":"Chemosphere","volume":"394 ","pages":"Article 144820"},"PeriodicalIF":8.1,"publicationDate":"2026-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145880339","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mercury contamination in a changing climate: One health approaches to human, wildlife, and ecosystem protection","authors":"Marília Cristina Oliveira Souza ,&nbsp;Fernando Barbosa Jr. ,&nbsp;Jose L. Domingo","doi":"10.1016/j.chemosphere.2025.144821","DOIUrl":"10.1016/j.chemosphere.2025.144821","url":null,"abstract":"<div><div>Mercury contamination exemplifies one of the most pressing global environmental health challenges of the 21st century, requiring integrated solutions that transcend disciplinary boundaries. This review provides the first comprehensive synthesis of mercury science through an explicit One Health lens, linking human, wildlife, and ecosystem health with the accelerating impacts of climate change. Mercury's global cycling and long-range transport generate interconnected exposure pathways, which simultaneously endanger human populations, biodiversity, and ecosystem integrity. The neurotoxic effects of methylmercury display remarkable cross-species consistency, driven by conserved mechanisms such as oxidative stress, mitochondrial dysfunction, and impaired neurodevelopment. Vulnerable groups, including pregnant women, lactating women, infants, children, populations with chronic comorbidities, indigenous communities, and apex predators, face disproportionate risks due to biomagnification and cumulative exposures. Despite regulatory advances, notably the Minamata Convention and its 2023 amendments, ongoing emissions and climate-driven perturbations continue to undermine management efforts. The present review identifies critical gaps in mixture toxicology, ecosystem-level consequences, and climate-mercury feedback. It proposes integrated interventions that simultaneously safeguard human health, wildlife populations, and environmental quality. By situating mercury contamination within the One Health framework, the review highlights the urgent need for coordinated transdisciplinary action to mitigate risks and advance planetary health.</div></div>","PeriodicalId":276,"journal":{"name":"Chemosphere","volume":"394 ","pages":"Article 144821"},"PeriodicalIF":8.1,"publicationDate":"2025-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145880338","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Perspective of the effect of caesium on nitrogen transport in the aquatic insect body of Kamimuria tibialis (Plecoptera) and Epeorus latifolium (Ephemeroptera)","authors":"Mayumi Yoshimura","doi":"10.1016/j.chemosphere.2025.144810","DOIUrl":"10.1016/j.chemosphere.2025.144810","url":null,"abstract":"<div><div>Cs is absorbed into the insect body in a manner similar to K. However, the degree of Cs absorption and its physiological activity in the insect body differ from those of K. Following the Fukushima nuclear power plant accident, radiocaesium was eluted and accumulated in streams. Consequently, aquatic insects exhibited uptake of radiocaesium; such contamination may have affected their body construction.</div><div>In this study, δ¹³C and δ¹⁵N values were compared between legs and heads of two aquatic insect species, <em>Kamimuria tibialis</em> and <em>Epeorus latifolium</em>, sampled in radiocaesium-contaminated and non-contaminated habitats. At the non-contaminated site, δ¹⁵N differed between legs and heads in both species, whereas at the contaminated site, δ¹⁵N values did not differ in <em>K. tibialis</em>. The disparity in δ¹⁵N between body parts in <em>K. tibialis</em> differed among sites and the difference was significant between contaminated and non-contaminated sites.</div><div>The amino acid symport mechanism appears to differ between species and may be altered by the presence of Cs in <em>K. tibialis</em>, possibly because of their behavior, foraging modes, and the mobility of other contaminants in stream. The correlative results of this study may provide insight into the effects of radiocaesium on amino acid transport in the aquatic insect body.</div></div>","PeriodicalId":276,"journal":{"name":"Chemosphere","volume":"394 ","pages":"Article 144810"},"PeriodicalIF":8.1,"publicationDate":"2025-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145880341","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"BiFeO3/graphitic-carbon/PVDF composite with an electrical percolation network to enhance ciprofloxacin removal by photoelectrocatalytic ozonation","authors":"R.L. Palomino-Resendiz ,&nbsp;A.B. Piña-Guzmán ,&nbsp;A.E. Yañez-Rios ,&nbsp;F.S. Sosa-Rodríguez ,&nbsp;R.M. Luna-Sanchez ,&nbsp;I.C. Romero-Ibarra ,&nbsp;L. Lartundo- Rojas ,&nbsp;J. Vazquez-Arenas","doi":"10.1016/j.chemosphere.2025.144811","DOIUrl":"10.1016/j.chemosphere.2025.144811","url":null,"abstract":"<div><div>Ternary BiFeO₃ (BFO)/Graphitic-Carbon/polyvinylidene fluoride (PVDF) composite photoanodes are fabricated at different compositions: 76:12:12, 80:10:10, and 90:5:5 wt% to account their influence during the degradation of 20 mg L⁻¹ ciprofloxacin (CIP, C₁₇H₁₈N₃FO₃) in synthetic water, using photoelectrocatalytic ozonation (PECO). BFO acts as active phase, Graphitic-Carbon as electronic conductor, and PVDF as binder. The crystalline structure of BFO synthesized by a high–energy ball milling method is confirmed by X-ray diffraction (XRD), Rietveld Refinement and Raman analysis; while Scanning Electronic Microscopy (SEM) images reveal an adequate dispersion on the substrate of all components for the 80:10:10 wt % composition, which differ in other composite ratios. Cross-sectional SEM imaging are also collected for the composites. XPS analysis confirms the presence of Bi³⁺ and Fe³⁺ species associated with the BFO phase. Optoelectronic and electrochemical characterizations conducted for all composites reveal that the 80:10:10 wt % composite generates a remarkable enhancement of 90 % CIP degradation after 60 min (Total Organic Carbon removal = 74.83 %) of treatment, according to high-performance liquid chromatography (HPLC) measurements. This was achieved due to the effective charge carriers separation (e⁻ and h⁺) in the BFO photoanode which is an n-type semiconductor, whence it requires the establishment of an interconnected network with a good electronic conductor like graphite expediting the charge transport to the cathode, and a binder to provide mechanical integrity to the entire composite. This is explained in terms of a photoelectrocatalytic mechanism rationalizing the electrical percolation network in the composites. The reaction mechanism of the CIP abatement is discussed along with the oxidants responsible for its elimination, detected by trapping tests with different scavengers. Toxicity bioassays conducted with <em>Daphnia magna</em> confirm that the water treated with the synergic PECO method is not toxic. Additionally, no physical, cardiac effects or alterations are observed in the swimming behavior of these organisms.</div></div>","PeriodicalId":276,"journal":{"name":"Chemosphere","volume":"394 ","pages":"Article 144811"},"PeriodicalIF":8.1,"publicationDate":"2025-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145880337","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Perfluorooctane sulfonic acid (PFOS) perturbs skeletal muscle oxidative phosphorylation by a different mechanism than liver","authors":"Jazmine A. Eccles-Miller ,&nbsp;Lanie A. Williams ,&nbsp;Elizabeth Leonard ,&nbsp;Nishanth Tharayil ,&nbsp;Elliet L. Buslee ,&nbsp;Joanna Fiddler ,&nbsp;William S. Baldwin","doi":"10.1016/j.chemosphere.2025.144815","DOIUrl":"10.1016/j.chemosphere.2025.144815","url":null,"abstract":"<div><div>PFOS perturbs normal energy metabolism such as lipid metabolism; however, despite being a highly metabolic organ, skeletal muscle toxicity has not been widely studied. Skeletal muscle, a healthy body's largest metabolic organ, presents a target for PFOS-induced metabolic toxicity due to its high mitochondrial content. Therefore, we aimed to evaluate the response of skeletal muscle to PFOS in vivo and compare the responses to liver. Mice were treated with 0, 1, or 10 mg/kg/day PFOS for 21-days and gastrocnemius and liver collected. All mice exhibited a dose-dependent decrease in bodyweight following PFOS treatment; only females were susceptible to loss of muscle mass. In contrast, liver weight increased in all mice. PFOS showed significant bioaccumulation in gastrocnemius, albeit lower than the liver. Despite reduced bioaccumulation, gastrocnemius was highly sensitive to transcriptomic changes. Only 5 % of differentially expressed genes were shared between the tissues. In gastrocnemius, mitochondrial OXPHOS pathways were highly sensitive to PFOS with ETC 1 most sensitive based on GO term and KEGG pathway analysis. In liver, PPAR transcription and fatty acid metabolism were some of the more sensitive pathways. Mitochondrial respiration assays (Seahorse) confirmed that complex I and IV capacity in PFOS-treated female gastrocnemius was repressed, whereas complex II capacity was repressed by PFOS treatment in liver. An increase in fast-oxidative fibers may have provided males, in comparison to females, some compensatory protection from the effects of PFOS. These results indicate that skeletal muscle is sensitive to PFOS toxicity, and PFOS perturbs different pathways in skeletal muscle than liver.</div></div>","PeriodicalId":276,"journal":{"name":"Chemosphere","volume":"394 ","pages":"Article 144815"},"PeriodicalIF":8.1,"publicationDate":"2025-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145879547","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Photocatalytic degradation of polyethylene microplastics by copper-doped titanium dioxide nanoparticles","authors":"Shibiru Yadeta Ejeta ,&nbsp;Toyoko Imae","doi":"10.1016/j.chemosphere.2025.144819","DOIUrl":"10.1016/j.chemosphere.2025.144819","url":null,"abstract":"<div><div>The rising prevalence of microplastics in aquatic environments poses significant environmental and ecological challenges. Although various methods have been tried to solve the issues of microplastics, most approaches are inefficient and energy-intensive, or involve surface-level removal rather than molecular degradation. This study explores the application of Cu-doped TiO₂ nanoparticles as efficient photocatalysts for the degradation of polyethylene microplastics under ultraviolet light irradiation. Cu-doping improves the light absorption efficiency and enhances the photocatalytic activity of TiO₂. Photocatalytic experiments using Cu-doped TiO₂ nanoparticles revealed a significant degradation of microplastics from tens of μm to a few μm, demonstrating superior performance compared to undoped TiO₂. The degradation of 96.7 % in the 48-h reaction was higher than that achieved by the pristine TiO₂ catalyst. According to reactive species-trapping experiments using scavengers, degradation reactions are mainly attributed to holes and reactive oxygen species, particularly hydroxy radical. Then the degradation mechanism staring from the generation of ^•OH in the valence band of the catalyst, was estimated. The unit species and terminal groups produced by the reaction process were consistent with those revealed by the infrared absorption spectra. These findings highlight the potential of photocatalytic reactions as valuable solutions for mitigating microplastic pollution.</div></div>","PeriodicalId":276,"journal":{"name":"Chemosphere","volume":"394 ","pages":"Article 144819"},"PeriodicalIF":8.1,"publicationDate":"2025-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145879520","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Box-modelling of HOx in Mexico City","authors":"Farah Jeba ,&nbsp;Bernhard Rappenglück ,&nbsp;Tanzina Akther ,&nbsp;Morshad Ahmed ,&nbsp;Armando Retama ,&nbsp;Olivia Rivera-Hernández","doi":"10.1016/j.chemosphere.2025.144813","DOIUrl":"10.1016/j.chemosphere.2025.144813","url":null,"abstract":"<div><div>This study presents an analysis of hydroxyl (OH) and hydroperoxyl (HO₂) radicals collectively referred to as HO_x and their role in atmospheric chemistry within the Mexico City Metropolitan Area (MCMA). HO_x radicals are paramount to the oxidative capacity of the atmosphere driving the formation of secondary pollutants such as ozone (O₃) and secondary organic aerosols (SOA). A 0-D chemical box model (AtChem-2) was employed to simulate in situ production of OH and HO₂ constrained by measurements of volatile organic compounds (VOCs), nitrogen oxides (NO_x), O₃, and other trace gases along with meteorological data collected during the campaign during the dry season. The analysis compares two distinct events: a pre-ozone episode with background conditions and an ozone episode characterized by strong photochemical activity confined to the MCMA. The results indicate significantly higher concentrations of OH and HO₂ of 0.49 ppt and 25.95 ppt respectively during the ozone episode driven by enhanced photolysis of O₃, HONO, and HCHO under clear sky conditions. HONO was identified as the dominant contributor with at least 2/3 to HO_x production averaged over daytime, followed by O₃ and HCHO. CO and VOCs have comparable effects on the loss rate of HO_x while NO_x plays the predominant role in the OH reactivity. The study reveals that elevated radical concentrations during the ozone episode corresponded to stronger and more persistent photochemical reactions by facilitating increased ozone formation of about 163 ppb. These findings underscore the importance of understanding radical production mechanisms in polluted urban environments particularly for the development strategies aimed at mitigating ozone and SOA levels.</div></div>","PeriodicalId":276,"journal":{"name":"Chemosphere","volume":"394 ","pages":"Article 144813"},"PeriodicalIF":8.1,"publicationDate":"2025-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145879523","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}