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Aghaei Y, Badami MM, Aldekheel M, Tohidi R, Sioutas C. Seasonal Characterization of Primary and Secondary Sources of Fine PM-Bound Water-Soluble Organic Carbon in Central Los Angeles. ATMOSPHERIC ENVIRONMENT (OXFORD, ENGLAND : 1994) 2025; 346:121084. [PMID: 39959759 PMCID: PMC11823697 DOI: 10.1016/j.atmosenv.2025.121084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/18/2025]
Abstract
Understanding the sources and formation processes of fine particulate matter (PM2.5) is crucial for improving urban air quality and public health. This study provides a real-time analysis of PM2.5-bound water-soluble organic carbon (WSOC) and related carbonaceous species during winter, spring, and summer periods in 2023-2024, aiming to identify their major sources in central Los Angeles. Using advanced online monitoring equipment, including a Sunset Laboratory EC/OC analyzer and a custom-developed setup including a total organic carbon (TOC) analyzer coupled with a particle collection system, we obtained hourly measurements of organic carbon (OC), its fractions (OC1-OC4, based on volatility), elemental carbon (EC), and WSOC. Positive matrix factorization (PMF) identified three principal PM2.5 sources: vehicular emissions, secondary organic carbon (SOC) formation influenced by nighttime aqueous-phase chemical processes, and SOC formation driven by daytime photochemical reactions. Vehicular emissions dominated EC levels, accounting for 86-95% across seasons. This factor also had high contributions from nitrogen oxides (NOₓ) (75-82%), vehicle counts (approximately 85%), and OC1 (51-83%), reflecting the persistent influence of traffic emissions. Nighttime SOC formation was significant in winter, with WSOC and OC4 contributing 58% and 40% to this factor. In contrast, daytime photochemical SOC formation was prominent in summer, with WSOC and OC4 contributing 63% and 47%, and ozone loading up to 89%, reflecting increased photochemical activity. Spring exhibited a mix of aqueous and photochemical SOC formation, with similar contributions from WSOC (38-35%) and OC4 (35-33%), reflecting the transitional season's mixed SOC formation mechanisms. Diurnal profiles revealed that primary emissions peaked during morning rush hours, while secondary formation processes elevated OC levels at night in winter and during afternoons in summer. The EC tracer method corroborated these findings by estimating primary and secondary organic carbon levels, highlighting significant seasonal and diurnal variations in carbonaceous aerosols. These results emphasize the need for targeted strategies addressing both primary emissions and the precursors of secondary aerosol formation, to improve air quality in Los Angeles.
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Affiliation(s)
- Yashar Aghaei
- University of Southern California, Department of Civil and Environmental Engineering, Los Angeles, California, USA
| | - Mohammad Mahdi Badami
- University of Southern California, Department of Civil and Environmental Engineering, Los Angeles, California, USA
| | - Mohammad Aldekheel
- University of Southern California, Department of Civil and Environmental Engineering, Los Angeles, California, USA
- Kuwait University, Department of Civil Engineering, P.O Box 5969, Safat 13060, Kuwait
| | - Ramin Tohidi
- University of Southern California, Department of Civil and Environmental Engineering, Los Angeles, California, USA
- Air Quality Planning and Science Division, California Air Resources Board, 4001 Iowa Avenue, Riverside, CA 92507, USA
| | - Constantinos Sioutas
- University of Southern California, Department of Civil and Environmental Engineering, Los Angeles, California, USA
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Gerber LS, de Leijer DCA, Rujas Arranz A, Lehmann JMML, Verheul ME, Cassee FR, Westerink RHS. Comparison of the neurotoxic potency of different ultrafine particle fractions from diesel engine exhaust following direct and simulated inhalation exposure. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 951:175469. [PMID: 39153615 DOI: 10.1016/j.scitotenv.2024.175469] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2024] [Revised: 08/05/2024] [Accepted: 08/10/2024] [Indexed: 08/19/2024]
Abstract
Exposure to traffic-related air pollution and ultrafine particles (<100 nm; UFP) is linked with neurodegeneration. However, the impact of the aromatic content in fuels and the contribution of different fractions of UFP, i.e., solid UFP vs SVOC UFP, on neuronal function is unknown. We therefore studied effects on neuronal activity and viability in rat primary cortical cells exposed for up to 120 h to copper oxide particles (CuO) or UFP (solid and SVOC) emitted from a heavy-duty diesel engine fueled with petroleum diesel (A20; 20 % aromatics) or Hydrotreated Vegetable Oil-type fuel (A0; 0.1 % aromatics), or solid UFP emitted from a non-road Kubota engine fueled with A20. Moreover, effects of UFP and CuO upon simulated inhalation exposure were studied by exposing an lung model (Calu-3 and THP-1 cells) for 48 h and subsequently exposing the cortical cells to the medium collected from the basal compartment of the lung model. Additionally, cell viability, cytotoxicity, barrier function, inflammation, and oxidative and cell stress were studied in the lung model after 48 h exposure to UFP and CuO. Compared to control, direct exposure to CuO and SVOC UFP decreased neuronal activity, which was partly associated with cytotoxicity. Effects on neuronal activity upon direct exposure to solid UFP were limited. A20-derived UFP (solid and SVOC) were more potent in altering neuronal function and viability than A0 counterparts. Effects on neuronal activity from simulated inhalation exposure were minor compared to direct exposures. In the lung model, CuO and A20-derived UFP increased cytokine release compared to control, whereas CuO and SVOC A20 altered gene expression indicative for oxidative stress. Our data indicate that SVOC UFP exhibit higher (neuro)toxic potency for altering neuronal activity in rat primary cortical cells than the solid fraction. Moreover, our data suggest that reducing the aromatic content in fuel decreases the (neuro)toxic potency of emitted UFP.
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Affiliation(s)
- Lora-Sophie Gerber
- Institute for Risk Assessment Sciences (IRAS), Faculty of Veterinary Medicine, Utrecht University, Utrecht, the Netherlands; National Institute for Public Health and the Environment (RIVM), Bilthoven, the Netherlands
| | - Dirk C A de Leijer
- Institute for Risk Assessment Sciences (IRAS), Faculty of Veterinary Medicine, Utrecht University, Utrecht, the Netherlands
| | - Andrea Rujas Arranz
- Institute for Risk Assessment Sciences (IRAS), Faculty of Veterinary Medicine, Utrecht University, Utrecht, the Netherlands
| | - Jonas M M L Lehmann
- Institute for Risk Assessment Sciences (IRAS), Faculty of Veterinary Medicine, Utrecht University, Utrecht, the Netherlands; National Institute for Public Health and the Environment (RIVM), Bilthoven, the Netherlands
| | - Meike E Verheul
- Institute for Risk Assessment Sciences (IRAS), Faculty of Veterinary Medicine, Utrecht University, Utrecht, the Netherlands
| | - Flemming R Cassee
- Institute for Risk Assessment Sciences (IRAS), Faculty of Veterinary Medicine, Utrecht University, Utrecht, the Netherlands; National Institute for Public Health and the Environment (RIVM), Bilthoven, the Netherlands
| | - Remco H S Westerink
- Institute for Risk Assessment Sciences (IRAS), Faculty of Veterinary Medicine, Utrecht University, Utrecht, the Netherlands.
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Chang C, Louie A, Zhou Y, Gupta R, Liang F, Xanthou G, Ereso J, Koletic C, Yang JC, Sedighian F, Lagishetty V, Arias-Jayo N, Altuwayjiri A, Tohidi R, Navab M, Reddy ST, Sioutas C, Hsiai T, Araujo JA, Jacobs JP. Ambient Particulate Matter Induces In Vitro Toxicity to Intestinal Epithelial Cells without Exacerbating Acute Colitis Induced by Dextran Sodium Sulfate or 2,4,6-Trinitrobenzenesulfonic Acid. Int J Mol Sci 2024; 25:7184. [PMID: 39000289 PMCID: PMC11241079 DOI: 10.3390/ijms25137184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2024] [Revised: 06/14/2024] [Accepted: 06/20/2024] [Indexed: 07/16/2024] Open
Abstract
Inflammatory bowel disease (IBD) is an immunologically complex disorder involving genetic, microbial, and environmental risk factors. Its global burden has continued to rise since industrialization, with epidemiological studies suggesting that ambient particulate matter (PM) in air pollution could be a contributing factor. Prior animal studies have shown that oral PM10 exposure promotes intestinal inflammation in a genetic IBD model and that PM2.5 inhalation exposure can increase intestinal levels of pro-inflammatory cytokines. PM10 and PM2.5 include ultrafine particles (UFP), which have an aerodynamic diameter of <0.10 μm and biophysical and biochemical properties that promote toxicity. UFP inhalation, however, has not been previously studied in the context of murine models of IBD. Here, we demonstrated that ambient PM is toxic to cultured Caco-2 intestinal epithelial cells and examined whether UFP inhalation affected acute colitis induced by dextran sodium sulfate and 2,4,6-trinitrobenzenesulfonic acid. C57BL/6J mice were exposed to filtered air (FA) or various types of ambient PM reaerosolized in the ultrafine size range at ~300 μg/m3, 6 h/day, 3-5 days/week, starting 7-10 days before disease induction. No differences in weight change, clinical disease activity, or histology were observed between the PM and FA-exposed groups. In conclusion, UFP inhalation exposure did not exacerbate intestinal inflammation in acute, chemically-induced colitis models.
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Affiliation(s)
- Candace Chang
- Vatche and Tamar Manoukian Division of Digestive Diseases, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095, USA; (C.C.); (Y.Z.); (F.L.); (G.X.); (J.E.); (C.K.); (J.C.Y.); (F.S.); (V.L.); (N.A.-J.)
- Division of Cardiology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095, USA; (A.L.); (R.G.); (M.N.); (S.T.R.); (T.H.)
- Department of Environmental Health Sciences, Fielding School of Public Health, University of California Los Angeles, Los Angeles, CA 90095, USA
- Molecular Toxicology Interdepartmental Program, University of California Los Angeles, Los Angeles, CA 90095, USA
| | - Allen Louie
- Division of Cardiology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095, USA; (A.L.); (R.G.); (M.N.); (S.T.R.); (T.H.)
- Department of Environmental Health Sciences, Fielding School of Public Health, University of California Los Angeles, Los Angeles, CA 90095, USA
- Molecular Toxicology Interdepartmental Program, University of California Los Angeles, Los Angeles, CA 90095, USA
| | - Yi Zhou
- Vatche and Tamar Manoukian Division of Digestive Diseases, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095, USA; (C.C.); (Y.Z.); (F.L.); (G.X.); (J.E.); (C.K.); (J.C.Y.); (F.S.); (V.L.); (N.A.-J.)
- West China Medical Center, Sichuan University, Chengdu 610017, China
| | - Rajat Gupta
- Division of Cardiology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095, USA; (A.L.); (R.G.); (M.N.); (S.T.R.); (T.H.)
- Department of Environmental Health Sciences, Fielding School of Public Health, University of California Los Angeles, Los Angeles, CA 90095, USA
- Molecular Toxicology Interdepartmental Program, University of California Los Angeles, Los Angeles, CA 90095, USA
| | - Fengting Liang
- Vatche and Tamar Manoukian Division of Digestive Diseases, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095, USA; (C.C.); (Y.Z.); (F.L.); (G.X.); (J.E.); (C.K.); (J.C.Y.); (F.S.); (V.L.); (N.A.-J.)
| | - Georgina Xanthou
- Vatche and Tamar Manoukian Division of Digestive Diseases, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095, USA; (C.C.); (Y.Z.); (F.L.); (G.X.); (J.E.); (C.K.); (J.C.Y.); (F.S.); (V.L.); (N.A.-J.)
| | - Jason Ereso
- Vatche and Tamar Manoukian Division of Digestive Diseases, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095, USA; (C.C.); (Y.Z.); (F.L.); (G.X.); (J.E.); (C.K.); (J.C.Y.); (F.S.); (V.L.); (N.A.-J.)
| | - Carolina Koletic
- Vatche and Tamar Manoukian Division of Digestive Diseases, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095, USA; (C.C.); (Y.Z.); (F.L.); (G.X.); (J.E.); (C.K.); (J.C.Y.); (F.S.); (V.L.); (N.A.-J.)
| | - Julianne Ching Yang
- Vatche and Tamar Manoukian Division of Digestive Diseases, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095, USA; (C.C.); (Y.Z.); (F.L.); (G.X.); (J.E.); (C.K.); (J.C.Y.); (F.S.); (V.L.); (N.A.-J.)
| | - Farzaneh Sedighian
- Vatche and Tamar Manoukian Division of Digestive Diseases, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095, USA; (C.C.); (Y.Z.); (F.L.); (G.X.); (J.E.); (C.K.); (J.C.Y.); (F.S.); (V.L.); (N.A.-J.)
| | - Venu Lagishetty
- Vatche and Tamar Manoukian Division of Digestive Diseases, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095, USA; (C.C.); (Y.Z.); (F.L.); (G.X.); (J.E.); (C.K.); (J.C.Y.); (F.S.); (V.L.); (N.A.-J.)
| | - Nerea Arias-Jayo
- Vatche and Tamar Manoukian Division of Digestive Diseases, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095, USA; (C.C.); (Y.Z.); (F.L.); (G.X.); (J.E.); (C.K.); (J.C.Y.); (F.S.); (V.L.); (N.A.-J.)
| | - Abdulmalik Altuwayjiri
- USC Viterbi School of Engineering, University of Southern California, Los Angeles, CA 90089, USA; (A.A.); (R.T.); (C.S.)
- Department of Civil and Environmental Engineering, College of Engineering, Majmaah University, Al-Majmaah 11952, Saudi Arabia
| | - Ramin Tohidi
- USC Viterbi School of Engineering, University of Southern California, Los Angeles, CA 90089, USA; (A.A.); (R.T.); (C.S.)
- Air Quality Planning and Science Division, California Air Resources Board, 4001 Iowa Avenue, Riverside, CA 92507, USA
| | - Mohamad Navab
- Division of Cardiology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095, USA; (A.L.); (R.G.); (M.N.); (S.T.R.); (T.H.)
| | - Srinivasa Tadiparthi Reddy
- Division of Cardiology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095, USA; (A.L.); (R.G.); (M.N.); (S.T.R.); (T.H.)
- West China Medical Center, Sichuan University, Chengdu 610017, China
- Molecular & Medical Pharmacology, University of California Los Angeles, Los Angeles, CA 90095, USA
| | - Constantinos Sioutas
- USC Viterbi School of Engineering, University of Southern California, Los Angeles, CA 90089, USA; (A.A.); (R.T.); (C.S.)
| | - Tzung Hsiai
- Division of Cardiology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095, USA; (A.L.); (R.G.); (M.N.); (S.T.R.); (T.H.)
- Henry Samueli School of Engineering, University of California Los Angeles, Los Angeles, CA 90095, USA
| | - Jesus A. Araujo
- Division of Cardiology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095, USA; (A.L.); (R.G.); (M.N.); (S.T.R.); (T.H.)
- Department of Environmental Health Sciences, Fielding School of Public Health, University of California Los Angeles, Los Angeles, CA 90095, USA
- Molecular Toxicology Interdepartmental Program, University of California Los Angeles, Los Angeles, CA 90095, USA
| | - Jonathan P. Jacobs
- Vatche and Tamar Manoukian Division of Digestive Diseases, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095, USA; (C.C.); (Y.Z.); (F.L.); (G.X.); (J.E.); (C.K.); (J.C.Y.); (F.S.); (V.L.); (N.A.-J.)
- Molecular Toxicology Interdepartmental Program, University of California Los Angeles, Los Angeles, CA 90095, USA
- Division of Gastroenterology, Hepatology and Parenteral Nutrition, Veterans Administration Greater Los Angeles Healthcare System, Los Angeles, CA 90073, USA
- Goodman-Luskin Microbiome Center, University of California Los Angeles, Los Angeles, CA 90095, USA
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Aghaei Y, Badami MM, Tohidi R, Subramanian PSG, Boffi R, Borgini A, De Marco C, Contiero P, Ruprecht AA, Verma V, Chatila T, Sioutas C. The Impact of Russia-Ukraine geopolitical conflict on the air quality and toxicological properties of ambient PM 2.5 in Milan, Italy. Sci Rep 2024; 14:5996. [PMID: 38472234 PMCID: PMC10933473 DOI: 10.1038/s41598-024-55292-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Accepted: 02/22/2024] [Indexed: 03/14/2024] Open
Abstract
The geopolitical conflict between Russia and Ukraine has disrupted Europe's natural gas supplies, driving up gas prices and leading to a shift towards biomass for residential heating during colder months. This study assessed the consequent air quality and toxicological impacts in Milan, Italy, focusing on fine particulate matter (PM2.5, dp < 2.5 μm) emissions. PM2.5 samples were analyzed for their chemical composition and assessed for their oxidative potential using the dithiothreitol (DTT) assay across three periods reflecting residential heating deployment (RHD): pre-RHD, intra-RHD, and post-RHD periods. During the intra-RHD period, PM2.5 levels were significantly higher than those in other periods, with concentrations reaching 57.94 ± 7.57 μg/m3, indicating a deterioration in air quality. Moreover, levoglucosan was 9.2 times higher during the intra-RHD period compared to the pre-RHD period, correlating with elevated levels of elemental carbon (EC) and polycyclic aromatic hydrocarbons (PAHs). These findings were compared with previous local studies before the conflict, underscoring a significant rise in biomass-related emissions. DTT assay levels during the intra-RHD were 2.1 times higher than those observed during the same period in 2022, strongly correlating with biomass burning emissions. Our findings highlight the necessity for policies to mitigate the indirect health effects of increased biomass burning emissions due to the energy crisis triggered by the geopolitical conflict.
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Affiliation(s)
- Yashar Aghaei
- Department of Civil and Environmental Engineering, University of Southern California, 3620 S. Vermont Ave. KAP210, Los Angeles, CA, 90089, USA
| | - Mohammad Mahdi Badami
- Department of Civil and Environmental Engineering, University of Southern California, 3620 S. Vermont Ave. KAP210, Los Angeles, CA, 90089, USA
| | - Ramin Tohidi
- Department of Civil and Environmental Engineering, University of Southern California, 3620 S. Vermont Ave. KAP210, Los Angeles, CA, 90089, USA
| | - P S Ganesh Subramanian
- Department of Civil and Environmental Engineering, University of Illinois at Urbana Champaign, Urbana, IL, USA
| | - Roberto Boffi
- Fondazione IRCCS, Istituto Nazionale Tumori, Milan, Italy
| | | | | | - Paolo Contiero
- Fondazione IRCCS, Istituto Nazionale Tumori, Milan, Italy
| | - Ario Alberto Ruprecht
- Fondazione IRCCS, Istituto Nazionale Tumori, Milan, Italy
- International Society of Doctors for Environment (ISDE), Arezzo, Italy
| | - Vishal Verma
- Department of Civil and Environmental Engineering, University of Illinois at Urbana Champaign, Urbana, IL, USA
| | - Talal Chatila
- Division of Immunology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Constantinos Sioutas
- Department of Civil and Environmental Engineering, University of Southern California, 3620 S. Vermont Ave. KAP210, Los Angeles, CA, 90089, USA.
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Duan L, Yu H, Wang Q, Wang F, Lin T, Cao Y, Guo Z. A comprehensive exploration of characteristics and source attribution of carbonaceous aerosols in PM 2.5 in an East China megacity. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 343:123239. [PMID: 38154782 DOI: 10.1016/j.envpol.2023.123239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2023] [Revised: 12/15/2023] [Accepted: 12/25/2023] [Indexed: 12/30/2023]
Abstract
A total of 84 PM2.5 (fine particulate matter) aerosol samples were collected between October 2020 and August 2021 within an urban site in Hangzhou, an East China megacity. Chemical species, such as organic carbon (OC), elemental carbon (EC), as well as char, soot, and n-alkanes, were analyzed to determine their pollution characteristics and source contributions. The mean yearly concentrations of OC, EC, char, soot, and total n-alkanes (∑n-alkane) were 8.76 ± 3.61 μg/m3, 1.44 ± 0.76 μg/m3, 1.21 ± 0.69 μg/m3, 0.3 ± 0.1 μg/m3, and 24.2 ± 10.6 ng/m3. The OC, EC, and ∑n-alkanes were found in the highest levels during winter and lowest during summer. There were strong correlations between OC and EC in both winter and spring, suggesting similar potential sources for these carbonaceous components in both seasons. There were poor correlations among the target pollutants due to summertime secondary organic carbon formation. Potential source contribution functions analysis showed that local pollution levels in winter and autumn were likely influenced by long-range transportation from the Plain of North China. Source index and positive matrix factorization models provided insights into the complex sources of n-alkanes in Hangzhou. Their major contributors were identified as terrestrial plant releases (32.7%), traffic emissions (28.8%), coal combustion (27.3%), and microbial activity (11.2%). Thus, controlling vehicular emissions and coal burning could be key measures to alleviate n-alkane concentrations in the atmosphere of Hangzhou, as well as other Chinese urban centers.
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Affiliation(s)
- Lian Duan
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai, 200438, China; Institute of Eco-Chongming (IEC), Shanghai, 200062, China
| | - Huimin Yu
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai, 200438, China
| | - Qiongzhen Wang
- Environmental Science Research & Design Institute of Zhejiang Province, Hangzhou, Zhejiang, 310007, China; Key Laboratory of Environmental Pollution Control Technology of Zhejiang Province, Hangzhou, 310007, China
| | - Fengwen Wang
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, College of Environment and Ecology, Chongqing University, Chongqing, 400030, China
| | - Tian Lin
- College of Marine Ecology and Environment, Shanghai Ocean University, Shanghai, 201306, China
| | - Yibo Cao
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai, 200438, China
| | - Zhigang Guo
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai, 200438, China; Institute of Eco-Chongming (IEC), Shanghai, 200062, China; State Environmental Protection Key Laboratory of Land and Sea Ecological Governance and Systematic Regulation, Shandong Academy for Environmental Planning, Jinan, 250101, China.
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Aldekheel M, Farahani VJ, Sioutas C. Assessing Lifetime Cancer Risk Associated with Population Exposure to PM-Bound PAHs and Carcinogenic Metals in Three Mid-Latitude Metropolitan Cities. TOXICS 2023; 11:697. [PMID: 37624202 PMCID: PMC10457896 DOI: 10.3390/toxics11080697] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 08/06/2023] [Accepted: 08/11/2023] [Indexed: 08/26/2023]
Abstract
Lifetime cancer risk characterization of ambient PM-bound carcinogenic metals and polycyclic aromatic hydrocarbons (PAHs) were examined in the cities of Los Angeles (USA), Thessaloniki (Greece) and Milan (Italy), which share similar Mediterranean climates but are different in their urban emission sources and governing air quality regulations. The samples in Milan and Thessaloniki were mostly dominated by biomass burning activities whereas the particles collected in Los Angeles were primary impacted by traffic emissions. We analyzed the ambient PM2.5 mass concentration of Cadmium (Cd), Hexavalent Chromium (Cr(VI)), Nickel (Ni), Lead (Pb), as well as 13 PAH compounds in the PM samples, collected during both cold and warm periods at each location. Pb exhibited the highest annual average concentration in all three cities, followed by Ni, As, Cr(VI), Cd and PAHs, respectively. The cancer risk assessment based on outdoor pollutants was performed based on three different scenarios, with each scenario corresponding to a different level of infiltration of outdoor pollutants into the indoor environment. Thessaloniki exhibited a high risk associated with lifetime inhalation of As, Cr(VI), and PAHs, with values in the range of (0.97-1.57) × 10-6, (1.80-2.91) × 10-6, and (0.77-1.25) × 10-6, respectively. The highest cancer risk values were calculated in Milan, exceeding the US EPA standard by a considerable margin, where the lifetime risk values of exposure to As, Cr(VI), and PAHs were in the range of (1.29-2.08) × 10-6, (6.08-9.82) × 10-6, and (1.10-1.77) × 10-6, respectively. In contrast, the estimated risks associated with PAHs and metals, except Cr(VI), in Los Angeles were extremely lower than the guideline value, even when the infiltration factor was assumed to be at peak. The lifetime cancer risk values associated with As, Cd, Ni, Pb, and PAHs in Los Angeles were in the range of (0.04-0.33) × 10-6. This observation highlights the impact of local air quality measures in improving the air quality and lowering the cancer risks in Los Angeles compared to the other two cities.
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Affiliation(s)
- Mohammad Aldekheel
- Department of Civil and Environmental Engineering, University of Southern California, Los Angeles, CA 90089, USA; (M.A.); (V.J.F.)
- Department of Civil Engineering, Kuwait University, P.O. Box 5969, Safat 13060, Kuwait
| | - Vahid Jalali Farahani
- Department of Civil and Environmental Engineering, University of Southern California, Los Angeles, CA 90089, USA; (M.A.); (V.J.F.)
| | - Constantinos Sioutas
- Department of Civil and Environmental Engineering, University of Southern California, Los Angeles, CA 90089, USA; (M.A.); (V.J.F.)
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Duan L, Yu H, Wang Q, Cao Y, Wang G, Sun X, Li H, Lin T, Guo Z. PM 2.5-bound polycyclic aromatic hydrocarbons of a megacity in eastern China: Source apportionment and cancer risk assessment. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 869:161792. [PMID: 36702280 DOI: 10.1016/j.scitotenv.2023.161792] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Revised: 01/19/2023] [Accepted: 01/19/2023] [Indexed: 06/18/2023]
Abstract
Ninety-six fine particulate matter (PM2.5) samples covering four seasons from October 2020 to August 2021 were collected at a 'super' site in Hangzhou, a megacity in eastern China. These samples were analyzed to determine the sources and potential cancer risks to humans of 16 United States Environmental Protection Agency priority polycyclic aromatic hydrocarbons (PAHs). The average concentrations of the PAHs in PM2.5 in autumn, winter, spring, and summer were 8.35 ± 4.90, 27.9 ± 13.6, 8.3 ± 5.97, and 1.05 ± 0.50 ng/m3, respectively, and with an annual average of 11.9 ± 13.2 ng/m3. The source apportionment by positive matrix factorization analysis indicated that, based on the yearly average, the major sources of PAHs were traffic emissions (38.2 %), coal combustion (28.9 %), coke (21.7 %), and volatilization (11.1 %). Strong correlations between high concentrations of carbonaceous aerosols and high-molecular-weight PAHs in winter could be attributed to incomplete combustion. Long-range transport of air from the sea to the southeast resulted in low concentrations of carbonaceous aerosols and low-molecular-weight PAHs in summer. Trajectory clustering and the potential source contribution function both indicated that the Yangtze River Delta was the main source region of PAHs for PM2.5 in Hangzhou in spring and summer. In autumn and winter, it was dominated by long-range transport from northern China. Lifetime lung cancer risk assessment revealed that the PAHs in PM2.5 impose moderate human health risks in Hangzhou due to traffic emissions. The results of this study provide important information for policymakers to establish abatement strategies to reduce PAH emissions in Hangzhou, and perhaps other urban centers across China.
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Affiliation(s)
- Lian Duan
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai 200438, China; Institute of Eco-Chongming (IEC), Shanghai 202162, China
| | - Huimin Yu
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai 200438, China
| | - Qiongzhen Wang
- Environmental Science Research & Design Institute of Zhejiang Province, Hangzhou, Zhejiang 310007, China
| | - Yibo Cao
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai 200438, China
| | - Guochen Wang
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai 200438, China
| | - Xueshi Sun
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai 200438, China
| | - Hao Li
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai 200438, China
| | - Tian Lin
- College of Marine Ecology and Environment, Shanghai Ocean University, Shanghai 201306, China
| | - Zhigang Guo
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai 200438, China; Institute of Eco-Chongming (IEC), Shanghai 202162, China.
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8
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Aldekheel M, Farahani VJ, Tohidi R, Altuwayjiri A, Sioutas C. Development and performance evaluation of a two-stage cascade impactor equipped with gelatin filter substrates for the collection of multi-sized particulate matter. ATMOSPHERIC ENVIRONMENT (OXFORD, ENGLAND : 1994) 2023; 294:119493. [PMID: 36504702 PMCID: PMC9733700 DOI: 10.1016/j.atmosenv.2022.119493] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
This study presents the development and evaluation of a high flow rate gelatin cascade impactor (GCI) to collect different PM particle sizes on water-soluble gelatin substrates. The GCI operates at a flow rate of 100 lpm, and consists of two impaction stages, followed by a filter holder to separate particles in the following diameter ranges: >2.5 μm, 0.2-2.5 μm, and <0.2 μm. Laboratory characterization of the GCI performance was conducted using monodisperse polystyrene latex (PSL) particles as well as polydisperse ammonium sulfate, sodium chloride, and ammonium nitrate aerosols to obtain the particle collection efficiency curves for both impaction stages. In addition to the laboratory characterization, we performed concurrent field experiments to collect PM2.5 employing both GCI equipped with gelatin filter and personal cascade impactor sampler (PCIS) equipped with PTFE filter for further toxicological analysis using macrophage-based reactive oxygen species (ROS) and dithiothreitol consumption (DTT) assays. Our results showed that the experimentally determined cut-point diameters for the first and second impaction stages were 2.4 μm and 0.21 μm, respectively, which agreed with the theoretical predictions. Although the GCI has been developed primarily to collect particles on gelatin filters, the use of a different type of substrate (i.e., quartz) led to similar particle separation characteristics. The findings of the field tests demonstrated the advantage of using the GCI in toxicological studies due to its ability to collect considerable PM-toxic constituents, as corroborated by the DTT and ROS values for the GCI-collected particles which were 26.44 nmoles/min/mg PM and 8813.2 μg Zymosan Units/mg PM, respectively. These redox activity values were more than twice those of particles collected concurrently on PTFE filter using the PCIS. This high-flow-rate impactor can collect considerable amounts of size-fractionated PM on water-soluble filters (i.e., gelatin), which can completely dissolve in water allowing for the extraction of soluble and insoluble PM species for further toxicological analysis.
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Affiliation(s)
- Mohammad Aldekheel
- University of Southern California, Department of Civil and Environmental Engineering, Los Angeles, California, USA
- Kuwait University, Department of Civil Engineering, P.O Box 5969, Safat 13060, Kuwait
| | - Vahid Jalali Farahani
- University of Southern California, Department of Civil and Environmental Engineering, Los Angeles, California, USA
| | - Ramin Tohidi
- University of Southern California, Department of Civil and Environmental Engineering, Los Angeles, California, USA
| | - Abdulmalik Altuwayjiri
- Department of Civil and Environmental Engineering, College of Engineering, Majmaah University, AL-Majmaah 11952, Saudi Arabia
| | - Constantinos Sioutas
- University of Southern California, Department of Civil and Environmental Engineering, Los Angeles, California, USA
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9
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Tohidi R, Altuwayjiri A, Sioutas C. Investigation of organic carbon profiles and sources of coarse PM in Los Angeles. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 314:120264. [PMID: 36162557 DOI: 10.1016/j.envpol.2022.120264] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2022] [Revised: 09/17/2022] [Accepted: 09/20/2022] [Indexed: 06/16/2023]
Abstract
Source apportionment analyses are essential tools to determine sources of ambient coarse particles (2.5 <dp < 10 μm) and to disentangle their association and contribution from other pollutants, particularly PM2.5 (<2.5 μm). A semi-continuous sampling campaign was conducted using two virtual impactors/concentrators to enhance coarse particulate matter concentrations coupled with an online thermal-optical EC/OC monitor to quantify coarse PM-bound organic carbon volatility fractions (OC1-OC4) in central Los Angeles during the winter, spring, and summer of 2021. The total OC and its volatility fraction concentrations, meteorological parameters (i.e., wind speeds and relative humidity), vehicle miles traveled (VMT), and gaseous source tracers (i.e., O3 and NO2) were used as inputs to positive matrix factorization (PMF) model. A 3-factor solution identified vehicular emissions (accounting for 46% in the cold phase and 26% in the warm phase of total coarse OC concentrations), secondary organic carbon (27% and 37%), and re-suspended dust (27% and 37%) as the primary organic carbon sources of coarse PM. The re-suspended dust factor showed a higher contribution of more volatile organic carbons (i.e., OC1 up to 77%) due to their re-distribution on dust particles, whereas the SOA factor was the dominant contributor to less volatile organic aerosols (i.e., OC4 up to 54%), which are the product of reactions at high relative humidity (RH). Our findings revealed that the total OC concentrations in the coarse size range were comparable with those of previous studies in the area, underscoring the challenges in curtailing coarse PM-bound OC sources and the necessity of developing effective emission control regulations on coarse PM. The results from the current study provide insights into the seasonal and temporal variation of total OC and its volatility fractions in Los Angeles.
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Affiliation(s)
- Ramin Tohidi
- University of Southern California, Department of Civil and Environmental Engineering, Los Angeles, CA, USA
| | - Abdulmalik Altuwayjiri
- Majmaah University, Department of Civil and Environmental Engineering, Majmaah, Riyadh, Saudi Arabia
| | - Constantinos Sioutas
- University of Southern California, Department of Civil and Environmental Engineering, Los Angeles, CA, USA.
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10
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Farahani VJ, Altuwayjiri A, Pirhadi M, Verma V, Ruprecht AA, Diapouli E, Eleftheriadis K, Sioutas C. The oxidative potential of particulate matter (PM) in different regions around the world and its relation to air pollution sources. ENVIRONMENTAL SCIENCE: ATMOSPHERES 2022; 2:1076-1086. [PMID: 36277745 PMCID: PMC9476553 DOI: 10.1039/d2ea00043a] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Accepted: 07/02/2022] [Indexed: 05/19/2023]
Abstract
In this study, we investigated the impact of urban emission sources on the chemical composition of ambient particulate matter (PM) as well as the associated oxidative potential. We collected six sets of PM samples in five urban location sites around the world over long time periods varying from weeks to months, intentionally selected for their PM to be dominated by unique emission sources: (1) PM2.5 produced mainly by traffic emissions in central Los Angeles, United States (US); (2) PM2.5 dominated by biomass burning in Milan, Italy; (3) PM2.5 formed by secondary photochemical reactions thus dominated by secondary aerosols in Athens, Greece; (4) PM10 emitted by refinery and dust resuspension in Riyadh, Saudi Arabia (SA); (5) PM10 generated by dust storms in Riyadh, SA, and (6) PM2.5 produced mainly by industrial and traffic emissions in Beirut, Lebanon. The PM samples were chemically analyzed and their oxidative potential were quantified by employing the dithiothreitol (DTT) assay. Our results revealed that the Milan samples were rich in water soluble organic carbon (WSOC) and PAHs, even exceeding the levels measured on Los Angeles (LA) freeways. The PM in Athens was characterized by high concentrations of inorganic ions, specifically sulfate which was the highest of all PM samples. The ambient PM in LA was impacted by the traffic-emitted primary organic and elemental carbon. Furthermore, the contribution of metals and elements per mass of PM in Riyadh and Beirut samples were more pronounced relative to other sampling areas. The highest intrinsic PM redox activity was observed for PM with the highest WSOC fraction, including Milan (biomass burning) and Athens (secondary organic aerosols, SOA). PM in areas characterized by high metal emissions including dust events, refinery and industry, such as Riyadh and Beirut, had the lowest oxidative potential as assessed by the DTT assay. The results of this study illustrate the impact of major emission sources in urban areas on the redox activity and oxidative potential of ambient PM, providing useful information for developing efficient air pollution control and mitigation policies in polluted areas around the globe.
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Affiliation(s)
- Vahid Jalali Farahani
- University of Southern California, Department of Civil and Environmental Engineering 3620 S. Vermont Ave, KAP210 Los Angeles California 90089 USA +1-213-744-1426 +1-213-740-6134
| | - Abdulmalik Altuwayjiri
- University of Southern California, Department of Civil and Environmental Engineering 3620 S. Vermont Ave, KAP210 Los Angeles California 90089 USA +1-213-744-1426 +1-213-740-6134
- Majmaah University, Department of Civil and Environmental Engineering Majmaah Riyadh Saudi Arabia
| | - Milad Pirhadi
- California Air Resources Board Sacramento California USA
| | - Vishal Verma
- University of Illinois at Urbana Champaign, Department of Civil and Environmental Engineering Urbana Illinois USA
| | | | - Evangelia Diapouli
- Environmental Radioactivity Laboratory, N.C.S.R. Demokritos 15341 Attiki Greece
| | | | - Constantinos Sioutas
- University of Southern California, Department of Civil and Environmental Engineering 3620 S. Vermont Ave, KAP210 Los Angeles California 90089 USA +1-213-744-1426 +1-213-740-6134
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11
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Pietrogrande MC, Bacco D, Demaria G, Russo M, Scotto F, Trentini A. Polycyclic aromatic hydrocarbons and their oxygenated derivatives in urban aerosol: levels, chemical profiles, and contribution to PM 2.5 oxidative potential. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:54391-54406. [PMID: 35297001 PMCID: PMC9356935 DOI: 10.1007/s11356-021-16858-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Accepted: 09/29/2021] [Indexed: 05/11/2023]
Abstract
The concentrations of polycyclic aromatic hydrocarbons (PAHs) and quinones, a subgroup of oxygenated PAHs (oxy-PAHs), were measured in PM2.5 samples collected during warm (May-June 2019) and cold (February-March 2020) seasons in the city of Bologna, Italy. Total PAHs concentration was nearly double in winter (6.58 ± 1.03 ng m-3) compared with spring (3.16 ± 0.53 ng m-3), following the trend of the PM2.5 mass concentration. Molecular diagnostic ratios suggested that, together with traffic, biomass burning was the dominant emission source contributing to the peaks of concentration of PM2.5 registered in the cold season. Quinone level was constant in both seasons, being 1.44 ± 0.24 ng m-3, that may be related to the increased secondary formation during warm season, as confirmed by the higher Σoxy-PAHs/ΣPAHs ratio in spring than in winter. The oxidative potential (OP) of the PM2.5 samples was assessed using acellular dithiothreitol (DTT) and ascorbic acid (AA) assays. The obtained responses showed a strong seasonality, with higher volume-normalized (OPV) values in winter than in spring, i.e., OPVDTT: 0.32 ± 0.15 nmol min-1 m-3 vs. 0.08 ± 0.03 nmol min-1 m-3 and OPVAA: 0.72 ± 0.36 nmol min-1 m-3 vs. 0.28 ± 0.21 nmol min-1 m-3. Both OPVDTT and OPVAA responses were significantly associated with total PAHs, as a general descriptor of redox-active PAH derivatives, associated with co-emission from burning sources or secondary atmospheric oxidation of parent PAHs. Otherwise, only winter OPVDTT responses showed a significant correlation with total Ʃoxy-PAHs concentration.
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Affiliation(s)
- Maria Chiara Pietrogrande
- Department of Chemical, Pharmaceutical and Agricultural Sciences, University of Ferrara, Via Fossato di Mortara 17/19 - 44121, Ferrara, Italy.
| | - Dimitri Bacco
- Emilia Romagna Regional Agency for Prevention, Environment and Energy, ARPAE, Via Po 5 - 40139, Bologna, Italy
| | - Giorgia Demaria
- Department of Chemical, Pharmaceutical and Agricultural Sciences, University of Ferrara, Via Fossato di Mortara 17/19 - 44121, Ferrara, Italy
| | - Mara Russo
- Department of Chemical, Pharmaceutical and Agricultural Sciences, University of Ferrara, Via Fossato di Mortara 17/19 - 44121, Ferrara, Italy
| | - Fabiana Scotto
- Emilia Romagna Regional Agency for Prevention, Environment and Energy, ARPAE, Via Po 5 - 40139, Bologna, Italy
| | - Arianna Trentini
- Emilia Romagna Regional Agency for Prevention, Environment and Energy, ARPAE, Via Po 5 - 40139, Bologna, Italy
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12
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Liu Y, Chan CK. The oxidative potential of fresh and aged elemental carbon-containing airborne particles: a review. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2022; 24:525-546. [PMID: 35333266 DOI: 10.1039/d1em00497b] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Elemental carbon is often found in ambient particulate matter (PM), and it contributes to the PM's oxidative potential (OP) and thus poses great health concerns. Previous review articles mainly focused on the methodologies in evaluating OP in PM and its relationship with selected chemical constituents, including metal ions, PAHs, and inorganic species. In recent years, growing attention has been paid to the effect of atmospheric aging processes on the OP of EC-containing airborne particles (ECCAPs). This review investigates more than 150 studies concerning the OP measurements and physico-chemical properties of both fresh and aged ECCAPs such as laboratory-generated elemental carbon (LGEC), carbon black (CB), soot (black carbon), and engineered carbon-containing nanomaterials (ECCBNs). Specifically, we summarize the characteristics of water-soluble and insoluble organic species, PAHs, quinone, and oxygen-containing functional groups (OFGs), and EC crystallinity. Both water-soluble organic carbon (WSOC) and water-insoluble organic carbon (WIOC) contribute to the OP. Low molecular weight (MW) PAHs show a higher correlation with OP than high MW PAHs. Furthermore, oxidative aging processes introduce OFGs, where quinone (CO) and epoxide (O-C-O) increase the OP of ECCAPs. In contrast, carboxyl (-COOH) and hydroxyl (-OH) slightly change the OP. The low crystallinity of EC favors the oxygen addition and forms active OFG quinone, thus increasing the OP. More detailed analyses for the EC microstructures and the organic coatings are needed to predict the OP of ECCAPs.
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Affiliation(s)
- Yangyang Liu
- School of Energy and Environment, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China.
| | - Chak K Chan
- School of Energy and Environment, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China.
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13
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Liu Z, Sun Y, Zeng Y, Guan Y, Huang Y, Chen Y, Li D, Mo L, Chen S, Mai B. Semi-volatile organic compounds in fine particulate matter on a tropical island in the South China Sea. JOURNAL OF HAZARDOUS MATERIALS 2022; 426:128071. [PMID: 34922134 DOI: 10.1016/j.jhazmat.2021.128071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Revised: 12/03/2021] [Accepted: 12/09/2021] [Indexed: 06/14/2023]
Abstract
Measurements of hazardous semi-volatile organic compounds (SVOCs) in remote tropical regions are rare. In this study, polycyclic aromatic compounds (PACs) [including polycyclic aromatic hydrocarbons (PAHs), nitrated PAHs (NPAHs), and oxygenated PAHs (OPAHs)], organophosphate esters (OPEs), and phthalic acid esters (PAEs) were measured in fine particulate matter (PM2.5) at Yongxing Island in the South China Sea (SCS). The concentrations of PACs (median = 53.5 pg/m3) were substantially low compared with previous measurements. The concentration weighted trajectory (CWT) model showed that the eastern and southern China was the main source region of PAC, occurring largely during the northeast (NE) monsoon. The PM2.5 showed remarkably high concentrations of OPEs (median = 3231 pg/m3) and moderate concentrations of PAEs (13,013 pg/m3). Some Southeast Asian countries were largely responsible for their higher concentrations, driven by the tropical SCS monsoons. We found significant atmospheric loss of the SVOCs, which is an explanation for the low concentrations of PACs. Enhanced formation of N/OPAHs originated from tropical regions was also observed. The positive matrix factorization model was applied to apportion the SVOC sources. The results, as well as correlation analyses of the SVOC concentrations, further indicate insignificant local sources and enhanced atmospheric reactions on this island.
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Affiliation(s)
- Zheng Liu
- School of Environment, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou 510006, China
| | - Yuxin Sun
- Key Laboratory of Tropical Marine Bio-Resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China
| | - Yuan Zeng
- School of Environment, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou 510006, China
| | - Yufeng Guan
- School of Environment, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou 510006, China
| | - Yuqi Huang
- School of Environment, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou 510006, China
| | - Yuping Chen
- School of Environment, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou 510006, China
| | - Daning Li
- Key Laboratory of Tropical Marine Bio-Resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China
| | - Ling Mo
- Water Quality Monitoring Section, Hainan Research Academy of Environmental Sciences, Haikou 571126, China
| | - Shejun Chen
- School of Environment, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou 510006, China.
| | - Bixian Mai
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
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14
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Feng T, Wang F, Yang F, Li Z, Lu P, Guo Z. Carbonaceous aerosols in urban Chongqing, China: Seasonal variation, source apportionment, and long-range transport. CHEMOSPHERE 2021; 285:131462. [PMID: 34252809 DOI: 10.1016/j.chemosphere.2021.131462] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Revised: 06/29/2021] [Accepted: 07/06/2021] [Indexed: 06/13/2023]
Abstract
Seventy-seven PM2.5 samples were collected at an urban site (Chongqing University Campus A) in October 2015 (autumn), December 2015 (winter), March 2016 (spring), and August 2016 (summer). These samples were analysed for organic carbon (OC), elemental carbon (EC), and their associated char, soot, 16 PAHs, and 28 n-alkanes to trace sources, and atmospheric transport pathways. The annual average of OC, EC, char, soot, ΣPAHs, and Σn-alkanes were 20.75 μg/m3, 6.18 μg/m3, 5.43 μg/m3, 0.75 μg/m3, 38.29 ng/m3, and 328.69 ng/m3, respectively. OC, ΣPAHs, and Σn-alkane concentrations were highest in winter and lowest in summer. EC, char, and soot concentrations were highest in autumn and lowest in winter. Source apportionment via positive matrix factorization (PMF) indicated that coal/biomass combustion-natural gas emissions (23.8%) and motor vehicle exhaust (20.2%) were the two major sources, followed by diesel and petroleum residue (21.1%), natural biogenic sources (17.7%), and evaporative/petrogenic sources (17.2%). The highest source contributor in autumn and winter was evaporative/petrogenic sources (30.6%) and natural biogenic sources (34.5%), respectively, whereas diesel engine emission contributed the most in spring and summer (32.1% and 38.0%, respectively). Potential source contribution function (PSCF) analysis identified southeastern Sichuan and northwestern Chongqing as the major potential sources of these pollutants. These datasets provide critical information for policymakers to establish abatement strategies for the reduction of carbonaceous pollutant emissions and improve air quality in Chongqing and other similar urban centres across China.
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Affiliation(s)
- Ting Feng
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing, 400030, China; Department of Environmental Science, Chongqing University, Chongqing, 400030, China
| | - Fengwen Wang
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing, 400030, China; Department of Environmental Science, Chongqing University, Chongqing, 400030, China; Key Laboratory for Urban Atmospheric Environment Integrated Observation & Pollution Prevention and Control of Chongqing, Chongqing Academy of Eco-Environmental Sciences, Chongqing, 401147, China.
| | - Fumo Yang
- Department of Environmental Science and Engineering, Sichuan University, Chengdu, 610065, China
| | - Zhenliang Li
- Key Laboratory for Urban Atmospheric Environment Integrated Observation & Pollution Prevention and Control of Chongqing, Chongqing Academy of Eco-Environmental Sciences, Chongqing, 401147, China
| | - Peili Lu
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing, 400030, China; Department of Environmental Science, Chongqing University, Chongqing, 400030, China
| | - Zhigang Guo
- Department of Environmental Science and Engineering, Fudan University, Shanghai, 200433, China
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15
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Farahani VJ, Pirhadi M, Sioutas C. Are standardized diesel exhaust particles (DEP) representative of ambient particles in air pollution toxicological studies? THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 788:147854. [PMID: 34029805 PMCID: PMC8206007 DOI: 10.1016/j.scitotenv.2021.147854] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 05/14/2021] [Accepted: 05/15/2021] [Indexed: 05/21/2023]
Abstract
In this study, we investigated the chemical characteristics of standardized diesel exhaust particles (DEP) and compared them to those of read-world particulate matter (PM) collected in different urban settings to evaluate the extent to which standardized DEPs can represent ambient particles for use in toxicological studies. Standard reference material SRM-2975 was obtained from the National Institute of Standards and Technology (NIST) and was chemically analyzed for the content of elemental carbon (EC), organic carbon (OC), polycyclic aromatic hydrocarbons (PAHs), inorganic ions, and several metals and trace elements. The analysis on the filter-collected DEP sample revealed very high levels of EC (i.e., ~397 ng/μg PM) which were comparable to the OC content (~405 ng/μg PM). This is in contrast with the carbonaceous content in the emitted particles from typical filter-equipped diesel-powered vehicles, in which low levels of EC emissions were observed. Furthermore, the EC mass fraction of the DEP sample did not match the observed levels in the ambient PM of multiple US urban areas, including Los Angeles (8%), Houston (~14%), Pittsburgh (~12%), and New York (~17%). Our results illustrated the lack of several high molecular weight carcinogenic PAHs in the DEP samples, unlike our measurements in major freeways of Los Angeles. Negligible levels of inorganic ions were observed in the sample and the DEP did not contain toxic secondary organic aerosols (SOAs) formed through synchronized reactions in the atmosphere. Lastly, the analysis of redox-active metals and trace elements demonstrated that the levels of many species including vehicle emission tracers (e.g., Ba, Ti, Mn, Fe) on Los Angeles roadways were almost 20 times greater than those in the DEP sample. Based on the abovementioned inconsistencies between the chemical composition of the DEP sample and those of real-world PM measured and recorded in different conditions, we conclude that the standardized DEPs are not suitable representatives of traffic emissions nor typical ambient PM to be used in toxicological studies.
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Affiliation(s)
- Vahid Jalali Farahani
- University of Southern California, Department of Civil and Environmental Engineering, Los Angeles, CA, USA
| | - Milad Pirhadi
- University of Southern California, Department of Civil and Environmental Engineering, Los Angeles, CA, USA
| | - Constantinos Sioutas
- University of Southern California, Department of Civil and Environmental Engineering, Los Angeles, CA, USA.
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16
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Shang X, Kang H, Chen Y, Abdumutallip M, Li L, Li X, Fu H, Wang X, Wang L, Wang X, Ouyang H, Tang X, Xiao H, George C, Chen J. PM 1.0-Nitrite Heterogeneous Formation Demonstrated via a Modified Versatile Aerosol Concentration Enrichment System Coupled with Ion Chromatography. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:9794-9804. [PMID: 34235924 DOI: 10.1021/acs.est.1c02373] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Particulate nitrite is a critical source of hydroxyl radicals; however, it lacks high-resolution methods due to its low abundance and stability to explore its formation mechanism. In this study, a modified versatile aerosol concentration enrichment system (VACES) coupled with ion chromatography (IC) was used to measure particulate NO2- hourly online and achieve a lowered detection limit of 10-3 μg m-3. VACES-IC was used to observe a high- and low-concentration events of PM1.0-NO2- in Shanghai, corresponding to the ambient-level concentrations of 0.34 and 0.05 μg m-3, respectively. The morning peak concentrations of NO2- even exceeded 3σ (standard deviation) in the high-concentration event due to the reduction of NO2 by aerosol SO32- based on kinetics and regression analysis. This implies that controlling SO2 emissions would be an effective strategy to decrease morning NO2- concentrations, correspondingly reducing the kinetic formation of SO42- by 20.8-34.8%. However, after sunrise, NO2- formation was primarily attributed to NO2 hydrolysis at pH 4.97-6.14. In the low-concentration event, NO2 hydrolysis also accounted for an overwhelming proportion (∼90%) of NO2- formation. This work estimates the contribution of different paths to particulate NO2- formation based on newly established high-resolution measurements.
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Affiliation(s)
- Xiaona Shang
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP3), Department of Environmental Science & Engineering, Fudan University, Shanghai 200438, China
| | - Huihui Kang
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP3), Department of Environmental Science & Engineering, Fudan University, Shanghai 200438, China
| | - Yunqian Chen
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP3), Department of Environmental Science & Engineering, Fudan University, Shanghai 200438, China
| | - Munira Abdumutallip
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP3), Department of Environmental Science & Engineering, Fudan University, Shanghai 200438, China
| | - Ling Li
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP3), Department of Environmental Science & Engineering, Fudan University, Shanghai 200438, China
| | - Xiang Li
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP3), Department of Environmental Science & Engineering, Fudan University, Shanghai 200438, China
| | - Hongbo Fu
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP3), Department of Environmental Science & Engineering, Fudan University, Shanghai 200438, China
| | - Xiaofei Wang
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP3), Department of Environmental Science & Engineering, Fudan University, Shanghai 200438, China
| | - Lin Wang
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP3), Department of Environmental Science & Engineering, Fudan University, Shanghai 200438, China
| | - Xinke Wang
- University Lyon, Université Claude Bernard Lyon 1, CNRS, IRCELYON, F-69626 Villeurbanne, France
| | - Huiling Ouyang
- IRDR International Center of Excellence on Risk Interconnectivity and Governance on Weather/Climate Extremes Impact and Public Health, Institute of Atmospheric Sciences, Fudan University, Shanghai 200438, China
| | - Xu Tang
- IRDR International Center of Excellence on Risk Interconnectivity and Governance on Weather/Climate Extremes Impact and Public Health, Institute of Atmospheric Sciences, Fudan University, Shanghai 200438, China
| | - Hang Xiao
- Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Christian George
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP3), Department of Environmental Science & Engineering, Fudan University, Shanghai 200438, China
- University Lyon, Université Claude Bernard Lyon 1, CNRS, IRCELYON, F-69626 Villeurbanne, France
| | - Jianmin Chen
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP3), Department of Environmental Science & Engineering, Fudan University, Shanghai 200438, China
- Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
- IRDR International Center of Excellence on Risk Interconnectivity and Governance on Weather/Climate Extremes Impact and Public Health, Institute of Atmospheric Sciences, Fudan University, Shanghai 200438, China
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Connor M, Lamorie-Foote K, Liu Q, Shkirkova K, Baertsch H, Sioutas C, Morgan TE, Finch CE, Mack WJ. Nanoparticulate matter exposure results in white matter damage and an inflammatory microglial response in an experimental murine model. PLoS One 2021; 16:e0253766. [PMID: 34214084 PMCID: PMC8253444 DOI: 10.1371/journal.pone.0253766] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Accepted: 06/14/2021] [Indexed: 01/25/2023] Open
Abstract
Exposure to ambient air pollution has been associated with white matter damage and neurocognitive decline. However, the mechanisms of this injury are not well understood and remain largely uncharacterized in experimental models. Prior studies have shown that exposure to particulate matter (PM), a sub-fraction of air pollution, results in neuroinflammation, specifically the upregulation of inflammatory microglia. This study examines white matter and axonal injury, and characterizes microglial reactivity in the corpus callosum of mice exposed to 10 weeks (150 hours) of PM. Nanoscale particulate matter (nPM, aerodynamic diameter ≤200 nm) consisting primarily of traffic-related emissions was collected from an urban area in Los Angeles. Male C57BL/6J mice were exposed to either re-aerosolized nPM or filtered air for 5 hours/day, 3 days/week, for 10 weeks (150 hours; n = 18/group). Microglia were characterized by immunohistochemical double staining of ionized calcium-binding protein-1 (Iba-1) with inducible nitric oxide synthase (iNOS) to identify pro-inflammatory cells, and Iba-1 with arginase-1 (Arg) to identify anti-inflammatory/ homeostatic cells. Myelin injury was assessed by degraded myelin basic protein (dMBP). Oligodendrocyte cell counts were evaluated by oligodendrocyte transcription factor 2 (Olig2). Axonal injury was assessed by axonal neurofilament marker SMI-312. iNOS-expressing microglia were significantly increased in the corpus callosum of mice exposed to nPM when compared to those exposed to filtered air (2.2 fold increase; p<0.05). This was accompanied by an increase in dMBP (1.4 fold increase; p<0.05) immunofluorescent density, a decrease in oligodendrocyte cell counts (1.16 fold decrease; p<0.05), and a decrease in neurofilament SMI-312 (1.13 fold decrease; p<0.05) immunofluorescent density. Exposure to nPM results in increased inflammatory microglia, white matter injury, and axonal degradation in the corpus callosum of adult male mice. iNOS-expressing microglia release cytokines and reactive oxygen/ nitrogen species which may further contribute to the white matter damage observed in this model.
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Affiliation(s)
- Michelle Connor
- Department of Neurosurgery, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Krista Lamorie-Foote
- Zilkha Neurogenetic Institute, University of Southern California, Los Angeles, California, United States of America
- * E-mail:
| | - Qinghai Liu
- Zilkha Neurogenetic Institute, University of Southern California, Los Angeles, California, United States of America
| | - Kristina Shkirkova
- Zilkha Neurogenetic Institute, University of Southern California, Los Angeles, California, United States of America
| | - Hans Baertsch
- Zilkha Neurogenetic Institute, University of Southern California, Los Angeles, California, United States of America
| | - Constantinos Sioutas
- Department of Civil and Environmental Engineering, Viterbi School of Engineering, University of Southern California, Los Angeles, California, United States of America
| | - Todd E. Morgan
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles, California, United States of America
| | - Caleb E. Finch
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles, California, United States of America
| | - William J. Mack
- Zilkha Neurogenetic Institute, University of Southern California, Los Angeles, California, United States of America
- Department of Neurological Surgery, Keck School of Medicine, University of Southern California, Los Angeles, California, United States of America
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Determination and Similarity Analysis of PM2.5 Emission Source Profiles Based on Organic Markers for Monterrey, Mexico. ATMOSPHERE 2021. [DOI: 10.3390/atmos12050554] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Source attribution of airborne particulate matter (PM) relies on a host of different chemical species. Organic molecular markers are a set of particularly useful marker compounds for estimating source contributions to the fine PM fraction (i.e., PM2.5). Although there are many source apportionment studies based on organic markers, these studies heavily rely on the few studies that report region-specific emission profiles. Source attribution efforts, particularly those conducted in countries with emerging economies, benefit from ad hoc information to conduct the corresponding analyses. In this study, we report organic molecular marker source profiles for PM2.5 emitted from 12 major sources types from five general source categories (meat cooking operations, vehicle exhausts, industries, biomass and trash burning, and urban background) for the Monterrey Metropolitan Area (Mexico). Source emission samples were obtained from a ground-based source-dominated sampling approach. Filter-based instruments were utilized, and the loaded filters were chemically characterized for organic markers by GC-MS. Levoglucosan and cholesterol dominate charbroiled-cooking operation sources while methoxyphenols, PAHs and hopanes dominate open-waste burning, vehicle exhaust and industrial emissions, respectively. A statistical analysis showed values of the Pearson distance < 0.4 and the similarity identity distance > 0.8 in all cases, indicating dissimilar source profiles. This was supported by the coefficient of divergence average values that ranged from 0.62 to 0.72. These profiles could further be utilized in receptor models to conduct source apportionment in regions with similar characteristics and can also be used to develop air pollution abatement strategies.
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Altuwayjiri A, Pirhadi M, Taghvaee S, Sioutas C. Long-term trends in the contribution of PM 2.5 sources to organic carbon (OC) in the Los Angeles basin and the effect of PM emission regulations. Faraday Discuss 2020; 226:74-99. [PMID: 33241815 DOI: 10.1039/d0fd00074d] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
This study aimed to investigate the long-term variations in the contributions of emission sources to ambient PM2.5 organic carbon (OC) in central Los Angeles (CELA) and Riverside using the Chemical Speciation Network (CSN) database in the 2005-2015 period, during which several federal and state PM-based regulations were implemented to reduce tailpipe emissions in the region. The measured concentrations of OC, OC volatility fractions (i.e., OC1, OC2, and OC3), elemental carbon (EC), ozone (O3), sulfate, the ratio of potassium ion to potassium (K+/K), and selected metal elements were used as the input to the positive matrix factorization (PMF) model. PMF resolved tailpipe emissions, non-tailpipe emissions, secondary organic aerosols (SOA), biomass burning, and local industrial activities as the main sources contributing to ambient OC at both sampling sites. Vehicular exhaust emissions, non-tailpipe emissions, and SOA were dominant sources of OC across our sampling sites, accounting cumulatively for more than 80% of total OC mass throughout the study period. Our findings showed a significant reduction in the absolute and relative contributions of tailpipe emissions to the ambient OC levels in CELA and Riverside over the time period of 2005-2015. The contribution of exhaust emissions to total OC in CELA decreased from 3.5 µg m-3 (49%) in 2005 to 1.5 µg m-3 (34%) in 2015, while similar trends were observed at Riverside during this period. These reductions are mainly attributed to the implementation of several federal, state, and local air quality regulations targeting tailpipe emissions in the area. The implementation of these regulations furthermore reduced the emissions of primary organic precursors of secondary aerosols, resulting in an overall decrease (although not statistically significant, P values ranging from 0.4 to 0.6) in SOA mass concentration in both locations over the study period. In contrast to the tailpipe emissions, we observed an increasing trend (by ∼4 to 14%) in the relative contribution of non-tailpipe emissions to OC over this time period at both sites. Our results demonstrated the effectiveness of air quality regulations in reducing direct tailpipe emissions in the area, but also underpinned the need to develop equally effective mitigation policies targeting non-tailpipe PM emissions.
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Affiliation(s)
- Abdulmalik Altuwayjiri
- University of Southern California, Department of Civil and Environmental Engineering, 3620 S. Vermont Ave. KAP210, Los Angeles, CA 90089, USA.
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Pirhadi M, Mousavi A, Sioutas C. Evaluation of a high flow rate electrostatic precipitator (ESP) as a particulate matter (PM) collector for toxicity studies. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 739:140060. [PMID: 32554118 PMCID: PMC7442709 DOI: 10.1016/j.scitotenv.2020.140060] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Revised: 05/20/2020] [Accepted: 06/05/2020] [Indexed: 05/07/2023]
Abstract
In this study, we investigated the performance of an electrostatic precipitator (ESP) operating at high flow rates (i.e., 50-100 lpm) as a fine particulate matter (PM2.5) collector for toxicological studies. The ESP optimum configuration (i.e., flow rate of 75 lpm and applied voltage of +12 kV) was determined based on maximum particle collection efficiencies and minimum ozone emissions associated with the instrument using different laboratory-generated aerosols. This configuration resulted in particle collection efficiencies above 80% for almost all particles in the size range of 0.015-2.5 μm while the ozone concentration was 17 ppb. The ESP was then deployed to our sampling site in central Los Angeles to evaluate its performance using ambient particles under the optimum configuration. Chemical composition and oxidative potential of PM2.5 samples collected on the foils placed inside the ESP tube were compared with those collected concurrently on filters and aerosol slurries using the versatile aerosol concentration enrichment system (VACES) operating in parallel. Our results demonstrated that the ESP was more efficient in preserving labile inorganic ions and total organic carbon (TOC) compared to filters. PM samples collected on ESP substrates also showed higher intrinsic oxidative potential compared to the filters, which might be the result of better preservation of redox active semi-volatile organic compounds on the ESP substrates. However, the TOC concentrations and intrinsic oxidative potential of PM samples collected on ESP substrates were somewhat lower than the aerosol slurries collected by the VACES, probably due to deficiency of water-insoluble compounds in extracted PM samples from ESP substrates. In conclusion, while particle collection for toxicological purposes by the ESP is somewhat inferior to a direct aerosol-into-liquid collection, the ESP performs equally well, if not better, than conventional filter samplers and can be utilized as a simple and adequately efficient PM collector for toxicological studies.
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Affiliation(s)
- Milad Pirhadi
- University of Southern California, Department of Civil and Environmental Engineering, Los Angeles, CA, USA
| | - Amirhosein Mousavi
- University of Southern California, Department of Civil and Environmental Engineering, Los Angeles, CA, USA
| | - Constantinos Sioutas
- University of Southern California, Department of Civil and Environmental Engineering, Los Angeles, CA, USA.
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21
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Airborne Aerosols and Human Health: Leapfrogging from Mass Concentration to Oxidative Potential. ATMOSPHERE 2020. [DOI: 10.3390/atmos11090917] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The mass concentration of atmospheric particulate matter (PM) has been systematically used in epidemiological studies as an indicator of exposure to air pollutants, connecting PM concentrations with a wide variety of human health effects. However, these effects can be hardly explained by using one single parameter, especially because PM is formed by a complex mixture of chemicals. Current research has shown that many of these adverse health effects can be derived from the oxidative stress caused by the deposition of PM in the lungs. The oxidative potential (OP) of the PM, related to the presence of transition metals and organic compounds that can induce the production of reactive oxygen and nitrogen species (ROS/RNS), could be a parameter to evaluate these effects. Therefore, estimating the OP of atmospheric PM would allow us to evaluate and integrate the toxic potential of PM into a unique parameter, which is related to emission sources, size distribution and/or chemical composition. However, the association between PM and particle-induced toxicity is still largely unknown. In this commentary article, we analyze how this new paradigm could help to deal with some unanswered questions related to the impact of atmospheric PM over human health.
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