Sources of particulate-matter air pollution and its oxidative potential in Europe

Nature, Journal Year: 2020, Volume and Issue: 587(7834), P. 414 - 419

Published: Nov. 18, 2020

Language: Английский

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Long-term phototransformation of microplastics under simulated sunlight irradiation in aquatic environments: Roles of reactive oxygen species

Water Research, Journal Year: 2020, Volume and Issue: 173, P. 115564 - 115564

Published: Jan. 29, 2020

Language: Английский

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Humic Acid and Fulvic Acid Hinder Long-Term Weathering of Microplastics in Lake Water

Environmental Science & Technology, Journal Year: 2021, Volume and Issue: 55(23), P. 15810 - 15820

Published: Nov. 10, 2021

We investigated the photoaging of polypropylene (PP) microplastics (MPs) in lake water. The results showed that PP MPs was significantly inhibited water compared with ultrapure after 12 d ultraviolet (UV) irradiation, and humic acid fulvic acid, rather than carbonate (CO32–), nitrate (NO3–), or chloride (Cl–) ions, were identified as primary contributors to observed inhibition. Mechanisms for roles (Suwannee River acid) (Pony Lake reducing rates photodegradation acted both reactive oxygen species (ROS) scavengers (e.g., •OH) (dominant contribution) optical light filters. As ROS scavengers, decreased capacity formation •OH O2•– by under irradiation. In addition, chromophores competed photons through light-shielding effect, thereby causing less fragmentation particles changes other properties (melting temperature, contact angle, surface zeta potential). proposed mechanisms inhibition will aid our efforts assess duration aging alterations MP during long-term weathering natural waters.

Language: Английский

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Organic Peroxides in Aerosol: Key Reactive Intermediates for Multiphase Processes in the Atmosphere

Chemical Reviews, Journal Year: 2023, Volume and Issue: 123(4), P. 1635 - 1679

Published: Jan. 11, 2023

Organic peroxides (POs) are organic molecules with one or more peroxide (−O–O−) functional groups. POs commonly regarded as chemically labile termination products from gas-phase radical chemistry and therefore serve temporary reservoirs for oxidative radicals (HOx ROx) in the atmosphere. Owing to their ubiquity, active gas-particle partitioning behavior, reactivity, key reactive intermediates atmospheric multiphase processes determining life cycle (formation, growth, aging), climate, health impacts of aerosol. However, there remain substantial gaps origin, molecular diversity, fate due complex nature dynamic behavior. Here, we summarize current understanding on POs, a focus identification quantification, state-of-the-art analytical developments, molecular-level formation mechanisms, chemical transformation pathways, well environmental impacts. We find that interactions SO2 transition metal ions generally fast PO pathways liquid water, lifetimes estimated be minutes hours, while hydrolysis is particularly important α-substituted hydroperoxides. Meanwhile, photolysis thermolysis likely minor sinks POs. These distinctly different fates, such reaction OH radicals, which highlights need understand By summarizing advances remaining challenges investigation propose future research priorities regarding fate,

Language: Английский

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Inorganic anions influenced the photoaging kinetics and mechanism of polystyrene microplastic under the simulated sunlight: Role of reactive radical species

Water Research, Journal Year: 2022, Volume and Issue: 216, P. 118294 - 118294

Published: March 16, 2022

Language: Английский

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The Association between Respiratory Infection and Air Pollution in the Setting of Air Quality Policy and Economic Change

Annals of the American Thoracic Society, Journal Year: 2018, Volume and Issue: unknown

Published: Nov. 6, 2018

Rationale: Fine particulate matter air pollution of 2.5 μm or less in diameter (PM2.5) has been associated with an increased risk respiratory disease, but assessments specific infections adults are lacking.Objectives: To estimate the rate infection healthcare encounters acute increases PM2.5 concentrations.Methods: Using case–crossover methods, we studied 498,118 adult New York State residents a primary diagnosis influenza, bacterial pneumonia, culture-negative pneumonia upon hospitalization emergency department (ED) visit (2005–2016). We estimated relative previous 1–7 days and explored differences before (2005–2007), during (2008–2013), after (2014–2016) implementation quality policies economic changes.Results: Interquartile range over 7 were excess rates (ERs) hospitalizations (2.5%; 95% confidence interval [CI], 1.7–3.2%) ED visits CI, 1.4–3.6%), ERs influenza (3.9%; 2.1–5.6%). Bacterial hospitalizations, not visits, and, though imprecise, similar magnitude to (Lag Day 6 ER, 2.3%; 0.3–4.3). Increased generally larger "after" period (P < 0.025 for both outcomes), compared "during" period, despite reductions overall concentrations.Conclusions: concentrations week, which persisted from changes. Though unexplained, this temporal variation may reflect altered toxicity different mixtures pathogen virulence.

Language: Английский

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Oxidative Potential of Water-Soluble Matter Associated with Chromophoric Substances in PM_2.5 over Xi’an, China

Environmental Science & Technology, Journal Year: 2019, Volume and Issue: 53(15), P. 8574 - 8584

Published: June 28, 2019

Organic compounds are important contributors to the oxidative potential (OP) of atmospheric aerosols. This study is first report OP water-soluble organic matter (WSOM) related chromophoric substances in PM2.5 over Xi'an, China. The dithiothreitol (DTT) activity levels extracted by water were quantified as well relationships between DTT and light absorption fluorescence properties. results show that has significantly correlated with colored WSOM, which we identified three absorbing (BrC1-3) eight fluorescent (C1-8). It further found BrC3 C7 accounted for almost all although these two factors contributed only a small fraction fluorescence. clearly distinguished from other because their long wavelength (λmax = 475 nm) emission 462 nm), respectively. discovery will help better interpret understand mechanism oxidation generation aerosols provide guidance predicting OPs based on optical

Language: Английский

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Enhanced cytotoxicity of photoaged phenol-formaldehyde resins microplastics: Combined effects of environmentally persistent free radicals, reactive oxygen species, and conjugated carbonyls

Environment International, Journal Year: 2020, Volume and Issue: 145, P. 106137 - 106137

Published: Sept. 19, 2020

Phenol-formaldehyde resin microplastic (PF-MP) is one of the major inhalable microplastics in environments released from manufacture, processing and usage PF materials. The associated toxicities PF-MP might be affected by photoaging. In this study, dynamic evolutions oxidative potential (OP) redox-active species, including environmentally persistent free radicals (EPFRs), reactive oxygen species (ROS), peroxides conjugated carbonyls, as well cytotoxicity were systematically investigated a result simulated sunlight irradiation. As photoaging time extended, OP increased. contents produced ROS PF-bound EPFRs due to light irradiation increased well, displayed significant correlations with (Spearman r > 0.6, p < 0.05). photoaged distinctly cellular reduced cell viability human lung epithelial adenocarcinoma cells (A549). showed similar trend level PF-MP, suggesting that active induced vitro toxicities. results not only highlight adverse health effects but also provide new perspectives for environmental risks airborne MPs.

Language: Английский

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Study on the oxidation potential of the water-soluble components of ambient PM2.5 over Xi’an, China: Pollution levels, source apportionment and transport pathways

Environment International, Journal Year: 2020, Volume and Issue: 136, P. 105515 - 105515

Published: Jan. 29, 2020

Reactive oxygen species (ROS) are a class of substances that general concern in terms human health and used to represent the oxidation potential (OP) atmosphere. In this study, ROS levels 116 daily fine particulate matter (PM2.5) samples taken over Xi'an 2017 were measured with dithiothreitol (DTT) method. The sources DTTv (volume-based DTT consumption) PM2.5 as well their contributions identified by both positive matrix factorization (PMF) multiple linear regression (MLR) based on chemical (PM). results showed yearly average was 0.53 nmol/min/m3 (0.19-1.10 nmol/min/m3). highest level occurred winter, followed spring, summer autumn. most strongly correlated water-soluble organic carbon (WSOC; r = 0.85), but effects WSOC very limited. SO2, NO2, CO, elemental (EC) K+ (r > 0.64) had moderate correlations moderately related environmentally persistent free radicals (EPFRs) 0.56). mixed-effects model pollutants originating from incomplete combustion greater than those complete combustion. Source apportionment PMF motor vehicle emissions (27.4%), secondary sulfates (21.6%) coal (18.8%) more important contributors dust (8.4%), metal processing (4.9%), industrial (11.3%) nitrates (7.5%). for consistent MLR results, which verified feasible methods source specific such EPFRs. Backward trajectory clusters dominant cluster groups local regional transport, while OP affected long-range transport transport. As stated above, improvement atmospheric require not only efforts also large-scale joint cooperation. Furthermore, study PM information provides guidance effect research.

Language: Английский

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Oxidative Potential of Particulate Matter and Generation of Reactive Oxygen Species in Epithelial Lining Fluid

Environmental Science & Technology, Journal Year: 2019, Volume and Issue: 53(21), P. 12784 - 12792

Published: Sept. 27, 2019

Reactive oxygen species (ROS) play a central role in adverse health effects of atmospheric particulate matter (PM). Respiratory deposition can lead to the formation ROS epithelial lining fluid due redox reactions PM components with lung antioxidants. As direct quantification is challenging, oxidative potential more commonly measured using antioxidant surrogates including dithiothreitol and ascorbic acid, assuming that decay corresponds formation. However, this assumption has not yet been validated lack respiratory tract causes major limitations evaluating impacts on stress. By combining field measurements size-segregated chemical composition, human model, kinetic modeling, we quantified production rates concentrations different types regions by considering particle-size-dependent deposition. The extrathoracic region found have higher compared bronchial alveolar regions. Although H2O2 O2- governed Fe Cu ions, OH radicals are mainly generated organic compounds Fenton-like metal ions. In winter when affected biomass burning, model comparisons suggest humic-like substances (HULIS) contribute substantially. We good indicator but does represent generation. These results provide rationale use as an toxicity epidemiological toxicological studies.

Language: Английский

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