1
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Katich JM, Apel EC, Bourgeois I, Brock CA, Bui TP, Campuzano-Jost P, Commane R, Daube B, Dollner M, Fromm M, Froyd KD, Hills AJ, Hornbrook RS, Jimenez JL, Kupc A, Lamb KD, McKain K, Moore F, Murphy DM, Nault BA, Peischl J, Perring AE, Peterson DA, Ray EA, Rosenlof KH, Ryerson T, Schill GP, Schroder JC, Weinzierl B, Thompson C, Williamson CJ, Wofsy SC, Yu P, Schwarz JP. Pyrocumulonimbus affect average stratospheric aerosol composition. Science 2023; 379:815-820. [PMID: 36821693 DOI: 10.1126/science.add3101] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
Pyrocumulonimbus (pyroCb) are wildfire-generated convective clouds that can inject smoke directly into the stratosphere. PyroCb have been tracked for years, yet their apparent rarity and episodic nature lead to highly uncertain climate impacts. In situ measurements of pyroCb smoke reveal its distinctive and exceptionally stable aerosol properties and define the long-term influence of pyroCb activity on the stratospheric aerosol budget. Analysis of 13 years of airborne observations shows that pyroCb are responsible for 10 to 25% of the black carbon and organic aerosols in the "present-day" lower stratosphere, with similar impacts in both the North and South Hemispheres. These results suggest that, should pyroCb increase in frequency and/or magnitude in future climates, they could generate dominant trends in stratospheric aerosol.
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Affiliation(s)
- J M Katich
- National Oceanic and Atmospheric Administration (NOAA) Chemical Sciences Laboratory (CSL), Boulder, CO, USA.,Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA
| | - E C Apel
- Atmospheric Chemistry Observations and Modeling Laboratory, National Center for Atmospheric Research, Boulder, CO, USA
| | - I Bourgeois
- National Oceanic and Atmospheric Administration (NOAA) Chemical Sciences Laboratory (CSL), Boulder, CO, USA.,Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA
| | - C A Brock
- National Oceanic and Atmospheric Administration (NOAA) Chemical Sciences Laboratory (CSL), Boulder, CO, USA
| | - T P Bui
- NASA Ames Research Center, Moffett Field, CA, USA
| | - P Campuzano-Jost
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA.,Department of Chemistry, University of Colorado, Boulder, CO, USA
| | - R Commane
- Department of Earth and Environmental Sciences and School of Engineering and Applied Sciences, Lamont-Doherty Earth Observatory, Columbia University, Palisades, NY, USA
| | - B Daube
- Department of Earth and Planetary Sciences, Harvard University, Cambridge, MA, USA
| | - M Dollner
- Aerosol Physics and Environmental Physics, Faculty of Physics, University of Vienna, Vienna, Austria
| | - M Fromm
- Naval Research Laboratory, Washington, DC, USA
| | - K D Froyd
- National Oceanic and Atmospheric Administration (NOAA) Chemical Sciences Laboratory (CSL), Boulder, CO, USA.,Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA
| | - A J Hills
- Atmospheric Chemistry Observations and Modeling Laboratory, National Center for Atmospheric Research, Boulder, CO, USA
| | - R S Hornbrook
- Atmospheric Chemistry Observations and Modeling Laboratory, National Center for Atmospheric Research, Boulder, CO, USA
| | - J L Jimenez
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA.,Department of Chemistry, University of Colorado, Boulder, CO, USA
| | - A Kupc
- National Oceanic and Atmospheric Administration (NOAA) Chemical Sciences Laboratory (CSL), Boulder, CO, USA.,Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA.,Aerosol Physics and Environmental Physics, Faculty of Physics, University of Vienna, Vienna, Austria
| | - K D Lamb
- National Oceanic and Atmospheric Administration (NOAA) Chemical Sciences Laboratory (CSL), Boulder, CO, USA.,Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA
| | - K McKain
- NOAA Global Monitoring Laboratory, Boulder, CO, USA
| | - F Moore
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA.,NOAA Global Monitoring Laboratory, Boulder, CO, USA
| | - D M Murphy
- National Oceanic and Atmospheric Administration (NOAA) Chemical Sciences Laboratory (CSL), Boulder, CO, USA
| | - B A Nault
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA.,Department of Chemistry, University of Colorado, Boulder, CO, USA.,Center for Aerosol and Cloud Chemistry, Aerodyne Research Inc., Billerica, MA, USA
| | - J Peischl
- National Oceanic and Atmospheric Administration (NOAA) Chemical Sciences Laboratory (CSL), Boulder, CO, USA.,Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA
| | - A E Perring
- Department of Chemistry, Colgate University, Hamilton, NY, USA
| | | | - E A Ray
- National Oceanic and Atmospheric Administration (NOAA) Chemical Sciences Laboratory (CSL), Boulder, CO, USA.,Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA
| | - K H Rosenlof
- National Oceanic and Atmospheric Administration (NOAA) Chemical Sciences Laboratory (CSL), Boulder, CO, USA
| | - T Ryerson
- National Oceanic and Atmospheric Administration (NOAA) Chemical Sciences Laboratory (CSL), Boulder, CO, USA
| | - G P Schill
- National Oceanic and Atmospheric Administration (NOAA) Chemical Sciences Laboratory (CSL), Boulder, CO, USA.,Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA
| | - J C Schroder
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA.,Department of Chemistry, University of Colorado, Boulder, CO, USA.,Colorado Department of Public Health and Environment, Denver, CO, USA
| | - B Weinzierl
- Department of Earth and Planetary Sciences, Harvard University, Cambridge, MA, USA
| | - C Thompson
- National Oceanic and Atmospheric Administration (NOAA) Chemical Sciences Laboratory (CSL), Boulder, CO, USA.,Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA
| | - C J Williamson
- National Oceanic and Atmospheric Administration (NOAA) Chemical Sciences Laboratory (CSL), Boulder, CO, USA.,Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA
| | - S C Wofsy
- Department of Earth and Planetary Sciences, Harvard University, Cambridge, MA, USA
| | - P Yu
- Institute of Environmental and Climate Research, Jinan University, Guangzhou, People's Republic of China
| | - J P Schwarz
- National Oceanic and Atmospheric Administration (NOAA) Chemical Sciences Laboratory (CSL), Boulder, CO, USA
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2
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Querol X, Alastuey A, Moreno N, Minguillón MC, Moreno T, Karanasiou A, Jimenez JL, Li Y, Morguí JA, Felisi JM. How can ventilation be improved on public transportation buses? Insights from CO 2 measurements. Environ Res 2022; 205:112451. [PMID: 34848209 DOI: 10.1016/j.envres.2021.112451] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Revised: 11/16/2021] [Accepted: 11/24/2021] [Indexed: 05/24/2023]
Abstract
Measurements of CO2 and counting of occupants were carried out in 37 public bus trips during commuting rush hours in Barcelona (NE Spain) with the aim of evaluating parameters governing ventilation inside the vehicles and proposing actions to improve it. The results show that CO2 concentrations (1039 and 934 ± 386 ppm, as average and median, during rush hours but with average reduced occupancy due to the fair to be infected by SARS-CoV-2 during the measurement period, and measured in the middle of the busses) are in the lower range of values recorded in the literature for public buses, however an improvement in ventilation is required in a significant proportion of the journeys. Thus, we found better ventilation in the older Euro 3+ (retrofitted with filter traps and selective catalytic reduction) and Euro 5 buses (average 918 ± 257 ppm) than in the hermetically closed new Euro 6 ones (1111 ± 432 ppm). The opening of the windows in the older buses yielded higher ventilation rates (778 ± 432 ppm). The opening of all doors at all stops increases the ventilation by causing a fall in concentrations of 200-350 ppm below inter-stop concentrations, with this effect typically lasting 40-50 s in the hermetically closed new Euro 6 hybrid buses. Based on these results a number of recommendations are offered in order to improve ventilation, including measurement of CO2 and occupancy, and installation of ventilation fans on the top of the hermetically closed new buses, introducing outdoor air when a given concentration threshold is exceeded. In these cases, a CO2 sensor installed in the outdoor air intake is also recommended to take into account external CO2 contributions.
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Affiliation(s)
- Xavier Querol
- Institute of Environmental Assessment and Water Research (IDAEA, CSIC), Barcelona, Spain.
| | - Andrés Alastuey
- Institute of Environmental Assessment and Water Research (IDAEA, CSIC), Barcelona, Spain
| | - Natalia Moreno
- Institute of Environmental Assessment and Water Research (IDAEA, CSIC), Barcelona, Spain
| | - Maria Cruz Minguillón
- Institute of Environmental Assessment and Water Research (IDAEA, CSIC), Barcelona, Spain
| | - Teresa Moreno
- Institute of Environmental Assessment and Water Research (IDAEA, CSIC), Barcelona, Spain
| | - Angeliki Karanasiou
- Institute of Environmental Assessment and Water Research (IDAEA, CSIC), Barcelona, Spain
| | - Jose Luis Jimenez
- Department of Chemistry and Cooperative Institute for Research in the Environmental Sciences, University of Colorado, Boulder, CO, USA
| | - Yuguo Li
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong, China
| | - Josep Antoni Morguí
- Departament de Biología Evolutiva, Ecología i Ciencies Ambientals, Universitat de Barcelona (DBEECA, UB), Barcelona, Spain
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3
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Peng Z, Rojas ALP, Kropff E, Bahnfleth W, Buonanno G, Dancer SJ, Kurnitski J, Li Y, Loomans MGLC, Marr LC, Morawska L, Nazaroff W, Noakes C, Querol X, Sekhar C, Tellier R, Greenhalgh T, Bourouiba L, Boerstra A, Tang JW, Miller SL, Jimenez JL. Practical Indicators for Risk of Airborne Transmission in Shared Indoor Environments and Their Application to COVID-19 Outbreaks. Environ Sci Technol 2022. [PMID: 34985868 DOI: 10.1101/2021.04.21.21255898] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Some infectious diseases, including COVID-19, can undergo airborne transmission. This may happen at close proximity, but as time indoors increases, infections can occur in shared room air despite distancing. We propose two indicators of infection risk for this situation, that is, relative risk parameter (Hr) and risk parameter (H). They combine the key factors that control airborne disease transmission indoors: virus-containing aerosol generation rate, breathing flow rate, masking and its quality, ventilation and aerosol-removal rates, number of occupants, and duration of exposure. COVID-19 outbreaks show a clear trend that is consistent with airborne infection and enable recommendations to minimize transmission risk. Transmission in typical prepandemic indoor spaces is highly sensitive to mitigation efforts. Previous outbreaks of measles, influenza, and tuberculosis were also assessed. Measles outbreaks occur at much lower risk parameter values than COVID-19, while tuberculosis outbreaks are observed at higher risk parameter values. Because both diseases are accepted as airborne, the fact that COVID-19 is less contagious than measles does not rule out airborne transmission. It is important that future outbreak reports include information on masking, ventilation and aerosol-removal rates, number of occupants, and duration of exposure, to investigate airborne transmission.
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Affiliation(s)
- Z Peng
- Dept. of Chemistry and CIRES, University of Colorado, Boulder, Colorado 80309, United States
| | - A L Pineda Rojas
- CIMA, UMI-IFAECI/CNRS, FCEyN, Universidad de Buenos Aires─UBA/CONICET, Buenos Aires C1428EGA, Argentina
| | - E Kropff
- Leloir Institute─IIBBA/CONICET, CBA, Buenos Aires C1405BWE, Argentina
| | - W Bahnfleth
- Dept. of Architectural Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - G Buonanno
- Dept. of Civil and Mechanical Engineering, University of Cassino and Southern Lazio, Cassino 03043, Italy
| | - S J Dancer
- Dept. of Microbiology, NHS Lanarkshire, Glasgow, Scotland G75 8RG, U.K
- School of Applied Sciences, Edinburgh Napier University, Edinburgh, Scotland EH11 4BN, U.K
| | - J Kurnitski
- REHVA Technology and Research Committee, Tallinn University of Technology, Tallinn 19086, Estonia
| | - Y Li
- Dept. of Mechanical Engineering, The University of Hong Kong, Hong Kong 999077, China
| | - M G L C Loomans
- Dept. of the Built Environment, Eindhoven University of Technology, Eindhoven 5612 AZ, The Netherlands
| | - L C Marr
- Dept. of Civil and Environmental Engineering, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - L Morawska
- International Laboratory for Air Quality and Health, Queensland University of Technology, Brisbane, Queensland 4001, Australia
| | - W Nazaroff
- Dept. of Civil and Environmental Engineering, University of California, Berkeley, California 94720, United States
| | - C Noakes
- School of Civil Engineering, University of Leeds, Leeds LS2 9JT, U.K
| | - X Querol
- Institute of Environmental Assessment and Water Research, IDAEA, Spanish Research Council, CSIC, Barcelona 08034, Spain
| | - C Sekhar
- Dept. of the Built Environment, National University of Singapore , 117566 Singapore
| | - R Tellier
- Dept. of Medicine, McGill University and McGill University Health Centre, Montreal, Québec H4A 3J1, Canada
| | - T Greenhalgh
- Nuffield Dept. of Primary Care Health Sciences, University of Oxford, Oxford OX2 6GG, U.K
| | - L Bourouiba
- The Fluid Dynamics of Disease Transmission Laboratory, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - A Boerstra
- REHVA (Federation of European Heating, Ventilation and Air Conditioning Associations), BBA Binnenmilieu, The Hague 2501 CJ, The Netherlands
| | - J W Tang
- Dept. of Respiratory Sciences, University of Leicester, Leicester LE1 7RH, U.K
| | - S L Miller
- Dept. of Mechanical Engineering, University of Colorado, Boulder, Colorado 80309, United States
| | - J L Jimenez
- Dept. of Chemistry and CIRES, University of Colorado, Boulder, Colorado 80309, United States
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4
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Peng Z, Rojas ALP, Kropff E, Bahnfleth W, Buonanno G, Dancer SJ, Kurnitski J, Li Y, Loomans MGLC, Marr LC, Morawska L, Nazaroff W, Noakes C, Querol X, Sekhar C, Tellier R, Greenhalgh T, Bourouiba L, Boerstra A, Tang JW, Miller SL, Jimenez JL. Practical Indicators for Risk of Airborne Transmission in Shared Indoor Environments and Their Application to COVID-19 Outbreaks. Environ Sci Technol 2022; 56:1125-1137. [PMID: 34985868 DOI: 10.1021/acs.est.1c06531] [Citation(s) in RCA: 60] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Some infectious diseases, including COVID-19, can undergo airborne transmission. This may happen at close proximity, but as time indoors increases, infections can occur in shared room air despite distancing. We propose two indicators of infection risk for this situation, that is, relative risk parameter (Hr) and risk parameter (H). They combine the key factors that control airborne disease transmission indoors: virus-containing aerosol generation rate, breathing flow rate, masking and its quality, ventilation and aerosol-removal rates, number of occupants, and duration of exposure. COVID-19 outbreaks show a clear trend that is consistent with airborne infection and enable recommendations to minimize transmission risk. Transmission in typical prepandemic indoor spaces is highly sensitive to mitigation efforts. Previous outbreaks of measles, influenza, and tuberculosis were also assessed. Measles outbreaks occur at much lower risk parameter values than COVID-19, while tuberculosis outbreaks are observed at higher risk parameter values. Because both diseases are accepted as airborne, the fact that COVID-19 is less contagious than measles does not rule out airborne transmission. It is important that future outbreak reports include information on masking, ventilation and aerosol-removal rates, number of occupants, and duration of exposure, to investigate airborne transmission.
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Affiliation(s)
- Z Peng
- Dept. of Chemistry and CIRES, University of Colorado, Boulder, Colorado 80309, United States
| | - A L Pineda Rojas
- CIMA, UMI-IFAECI/CNRS, FCEyN, Universidad de Buenos Aires─UBA/CONICET, Buenos Aires C1428EGA, Argentina
| | - E Kropff
- Leloir Institute─IIBBA/CONICET, CBA, Buenos Aires C1405BWE, Argentina
| | - W Bahnfleth
- Dept. of Architectural Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - G Buonanno
- Dept. of Civil and Mechanical Engineering, University of Cassino and Southern Lazio, Cassino 03043, Italy
| | - S J Dancer
- Dept. of Microbiology, NHS Lanarkshire, Glasgow, Scotland G75 8RG, U.K
- School of Applied Sciences, Edinburgh Napier University, Edinburgh, Scotland EH11 4BN, U.K
| | - J Kurnitski
- REHVA Technology and Research Committee, Tallinn University of Technology, Tallinn 19086, Estonia
| | - Y Li
- Dept. of Mechanical Engineering, The University of Hong Kong, Hong Kong 999077, China
| | - M G L C Loomans
- Dept. of the Built Environment, Eindhoven University of Technology, Eindhoven 5612 AZ, The Netherlands
| | - L C Marr
- Dept. of Civil and Environmental Engineering, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - L Morawska
- International Laboratory for Air Quality and Health, Queensland University of Technology, Brisbane, Queensland 4001, Australia
| | - W Nazaroff
- Dept. of Civil and Environmental Engineering, University of California, Berkeley, California 94720, United States
| | - C Noakes
- School of Civil Engineering, University of Leeds, Leeds LS2 9JT, U.K
| | - X Querol
- Institute of Environmental Assessment and Water Research, IDAEA, Spanish Research Council, CSIC, Barcelona 08034, Spain
| | - C Sekhar
- Dept. of the Built Environment, National University of Singapore , 117566 Singapore
| | - R Tellier
- Dept. of Medicine, McGill University and McGill University Health Centre, Montreal, Québec H4A 3J1, Canada
| | - T Greenhalgh
- Nuffield Dept. of Primary Care Health Sciences, University of Oxford, Oxford OX2 6GG, U.K
| | - L Bourouiba
- The Fluid Dynamics of Disease Transmission Laboratory, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - A Boerstra
- REHVA (Federation of European Heating, Ventilation and Air Conditioning Associations), BBA Binnenmilieu, The Hague 2501 CJ, The Netherlands
| | - J W Tang
- Dept. of Respiratory Sciences, University of Leicester, Leicester LE1 7RH, U.K
| | - S L Miller
- Dept. of Mechanical Engineering, University of Colorado, Boulder, Colorado 80309, United States
| | - J L Jimenez
- Dept. of Chemistry and CIRES, University of Colorado, Boulder, Colorado 80309, United States
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5
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Randall K, Ewing ET, Marr LC, Jimenez JL, Bourouiba L. How did we get here: what are droplets and aerosols and how far do they go? A historical perspective on the transmission of respiratory infectious diseases. Interface Focus 2021; 11:20210049. [PMID: 34956601 PMCID: PMC8504878 DOI: 10.1098/rsfs.2021.0049] [Citation(s) in RCA: 47] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/13/2021] [Indexed: 12/19/2022] Open
Abstract
The COVID-19 pandemic has exposed major gaps in our understanding of the transmission of viruses through the air. These gaps slowed recognition of airborne transmission of the disease, contributed to muddled public health policies and impeded clear messaging on how best to slow transmission of COVID-19. In particular, current recommendations have been based on four tenets: (i) respiratory disease transmission routes can be viewed mostly in a binary manner of ‘droplets’ versus ‘aerosols’; (ii) this dichotomy depends on droplet size alone; (iii) the cut-off size between these routes of transmission is 5 µm; and (iv) there is a dichotomy in the distance at which transmission by each route is relevant. Yet, a relationship between these assertions is not supported by current scientific knowledge. Here, we revisit the historical foundation of these notions, and how they became entangled from the 1800s to today, with a complex interplay among various fields of science and medicine. This journey into the past highlights potential solutions for better collaboration and integration of scientific results into practice for building a more resilient society with more sound, far-sighted and effective public health policies.
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Affiliation(s)
- K Randall
- Department of Civil & Environmental Engineering, Virginia Tech, Blacksburg, VA, USA
| | - E T Ewing
- Department of Civil & Environmental Engineering, Virginia Tech, Blacksburg, VA, USA
| | - L C Marr
- Department of Civil & Environmental Engineering, Virginia Tech, Blacksburg, VA, USA
| | - J L Jimenez
- Department of Chemistry and CIRES, University of Colorado, Boulder, CO, USA
| | - L Bourouiba
- Fluid Dynamics of Disease Transmission Laboratory, Massachusetts Institute of Technology, Cambridge, MA, USA
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6
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Tang JW, Bahnfleth WP, Bluyssen PM, Buonanno G, Jimenez JL, Kurnitski J, Li Y, Miller S, Sekhar C, Morawska L, Marr LC, Melikov AK, Nazaroff WW, Nielsen PV, Tellier R, Wargocki P, Dancer SJ. Dismantling myths on the airborne transmission of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). J Hosp Infect 2021; 110:89-96. [PMID: 33453351 PMCID: PMC7805396 DOI: 10.1016/j.jhin.2020.12.022] [Citation(s) in RCA: 179] [Impact Index Per Article: 59.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Revised: 12/21/2020] [Accepted: 12/23/2020] [Indexed: 12/20/2022]
Abstract
The coronavirus disease 2019 (COVID-19) pandemic has caused untold disruption throughout the world. Understanding the mechanisms for transmission of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is key to preventing further spread, but there is confusion over the meaning of ‘airborne’ whenever transmission is discussed. Scientific ambivalence originates from evidence published many years ago which has generated mythological beliefs that obscure current thinking. This article collates and explores some of the most commonly held dogmas on airborne transmission in order to stimulate revision of the science in the light of current evidence. Six ‘myths’ are presented, explained and ultimately refuted on the basis of recently published papers and expert opinion from previous work related to similar viruses. There is little doubt that SARS-CoV-2 is transmitted via a range of airborne particle sizes subject to all the usual ventilation parameters and human behaviour. Experts from specialties encompassing aerosol studies, ventilation, engineering, physics, virology and clinical medicine have joined together to produce this review to consolidate the evidence for airborne transmission mechanisms, and offer justification for modern strategies for prevention and control of COVID-19 in health care and the community.
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Affiliation(s)
- J W Tang
- Respiratory Sciences, University of Leicester, Leicester, UK
| | - W P Bahnfleth
- Department of Architectural Engineering, The Pennsylvania State University, State College, PA, USA
| | - P M Bluyssen
- Faculty of Architecture and the Built Environment, Delft University of Technology, Delft, The Netherlands
| | - G Buonanno
- Department of Civil and Mechanical Engineering, University of Cassino and Southern Lazio, Cassino, Italy
| | - J L Jimenez
- Department of Chemistry and CIRES, University of Colorado, Boulder, CO, USA
| | - J Kurnitski
- REHVA Technology and Research Committee, Tallinn University of Technology, Tallinn, Estonia
| | - Y Li
- Department of Mechanical Engineering, University of Hong Kong, Hong Kong, China
| | - S Miller
- Mechanical Engineering, University of Colorado, Boulder, CO, USA
| | - C Sekhar
- Department of Building, National University of Singapore, Singapore
| | - L Morawska
- International Laboratory for Air Quality and Health, Queensland University of Technology, Brisbane, QLD, Australia
| | - L C Marr
- Civil and Environmental Engineering, Virginia Tech, Blacksburg, VA, USA
| | - A K Melikov
- International Centre for Indoor Environment and Energy, Department of Civil Engineering, Technical University of Denmark, Kongens Lyngby, Denmark
| | - W W Nazaroff
- Department of Civil and Environmental Engineering, University of California, Berkeley, CA, USA
| | - P V Nielsen
- Faculty of Engineering and Science, Department of Civil Engineering, Aalborg University, Aalborg, Denmark
| | - R Tellier
- Department of Medicine, McGill University, Montreal, QC, Canada
| | - P Wargocki
- International Centre for Indoor Environment and Energy, Department of Civil Engineering, Technical University of Denmark, Kongens Lyngby, Denmark
| | - S J Dancer
- Department of Microbiology, NHS Lanarkshire, Glasgow, UK; School of Applied Sciences, Edinburgh Napier University, Edinburgh, UK.
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7
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Farmer DK, Vance ME, Abbatt JPD, Abeleira A, Alves MR, Arata C, Boedicker E, Bourne S, Cardoso-Saldaña F, Corsi R, DeCarlo PF, Goldstein AH, Grassian VH, Hildebrandt Ruiz L, Jimenez JL, Kahan TF, Katz EF, Mattila JM, Nazaroff WW, Novoselac A, O'Brien RE, Or VW, Patel S, Sankhyan S, Stevens PS, Tian Y, Wade M, Wang C, Zhou S, Zhou Y. Overview of HOMEChem: House Observations of Microbial and Environmental Chemistry. Environ Sci Process Impacts 2019; 21:1280-1300. [PMID: 31328749 DOI: 10.1039/c9em00228f] [Citation(s) in RCA: 74] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The House Observations of Microbial and Environmental Chemistry (HOMEChem) study is a collaborative field investigation designed to probe how everyday activities influence the emissions, chemical transformations and removal of trace gases and particles in indoor air. Sequential and layered experiments in a research house included cooking, cleaning, variable occupancy, and window-opening. This paper describes the overall design of HOMEChem and presents preliminary case studies investigating the concentrations of reactive trace gases, aerosol particles, and surface films. Cooking was a large source of VOCs, CO2, NOx, and particles. By number, cooking particles were predominantly in the ultrafine mode. Organic aerosol dominated the submicron mass, and, while variable between meals and throughout the cooking process, was dominated by components of hydrocarbon character and low oxygen content, similar to cooking oil. Air exchange in the house ensured that cooking particles were present for only short periods. During unoccupied background intervals, particle concentrations were lower indoors than outdoors. The cooling coils of the house ventilation system induced cyclic changes in water soluble gases. Even during unoccupied periods, concentrations of many organic trace gases were higher indoors than outdoors, consistent with housing materials being potential sources of these compounds to the outdoor environment. Organic material accumulated on indoor surfaces, and exhibited chemical signatures similar to indoor organic aerosol.
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Affiliation(s)
- D K Farmer
- Department of Chemistry, Colorado State University, Fort Collins, CO, USA 80523.
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8
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Platt SM, El Haddad I, Pieber SM, Zardini AA, Suarez-Bertoa R, Clairotte M, Daellenbach KR, Huang RJ, Slowik JG, Hellebust S, Temime-Roussel B, Marchand N, de Gouw J, Jimenez JL, Hayes PL, Robinson AL, Baltensperger U, Astorga C, Prévôt ASH. Gasoline cars produce more carbonaceous particulate matter than modern filter-equipped diesel cars. Sci Rep 2017; 7:4926. [PMID: 28706240 PMCID: PMC5509693 DOI: 10.1038/s41598-017-03714-9] [Citation(s) in RCA: 101] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2016] [Accepted: 05/10/2017] [Indexed: 11/17/2022] Open
Abstract
Carbonaceous particulate matter (PM), comprising black carbon (BC), primary organic aerosol (POA) and secondary organic aerosol (SOA, from atmospheric aging of precursors), is a highly toxic vehicle exhaust component. Therefore, understanding vehicle pollution requires knowledge of both primary emissions, and how these emissions age in the atmosphere. We provide a systematic examination of carbonaceous PM emissions and parameterisation of SOA formation from modern diesel and gasoline cars at different temperatures (22, -7 °C) during controlled laboratory experiments. Carbonaceous PM emission and SOA formation is markedly higher from gasoline than diesel particle filter (DPF) and catalyst-equipped diesel cars, more so at -7 °C, contrasting with nitrogen oxides (NOX). Higher SOA formation from gasoline cars and primary emission reductions for diesels implies gasoline cars will increasingly dominate vehicular total carbonaceous PM, though older non-DPF-equipped diesels will continue to dominate the primary fraction for some time. Supported by state-of-the-art source apportionment of ambient fossil fuel derived PM, our results show that whether gasoline or diesel cars are more polluting depends on the pollutant in question, i.e. that diesel cars are not necessarily worse polluters than gasoline cars.
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Affiliation(s)
- S M Platt
- Paul Scherrer Institute, Laboratory of Atmospheric Chemistry, CH-5232, Villigen, Switzerland
- NILU-Norwegian Institute for Air Research, PO Box 100, 2027, Kjeller, Norway
| | - I El Haddad
- Paul Scherrer Institute, Laboratory of Atmospheric Chemistry, CH-5232, Villigen, Switzerland.
| | - S M Pieber
- Paul Scherrer Institute, Laboratory of Atmospheric Chemistry, CH-5232, Villigen, Switzerland
| | - A A Zardini
- European Commission Joint Research Centre, Directorate for Energy, Transport and Climate, Sustainable Transport Unit, 21027, Ispra, (VA), Italy
| | - R Suarez-Bertoa
- European Commission Joint Research Centre, Directorate for Energy, Transport and Climate, Sustainable Transport Unit, 21027, Ispra, (VA), Italy
| | - M Clairotte
- European Commission Joint Research Centre, Directorate for Energy, Transport and Climate, Sustainable Transport Unit, 21027, Ispra, (VA), Italy
| | - K R Daellenbach
- Paul Scherrer Institute, Laboratory of Atmospheric Chemistry, CH-5232, Villigen, Switzerland
| | - R-J Huang
- Paul Scherrer Institute, Laboratory of Atmospheric Chemistry, CH-5232, Villigen, Switzerland
- Key Laboratory of Aerosol Chemistry & Physics, State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, 710061, China
| | - J G Slowik
- Paul Scherrer Institute, Laboratory of Atmospheric Chemistry, CH-5232, Villigen, Switzerland
| | - S Hellebust
- Aix Marseille Univ, CNRS, LCE, Marseille, France
- Central Statistics Office, Cork, Ireland
| | | | - N Marchand
- Aix Marseille Univ, CNRS, LCE, Marseille, France
| | - J de Gouw
- NOAA Earth System Research Laboratory, Boulder, CO, USA
- CIRES, University of Colorado, Boulder, CO, USA
| | - J L Jimenez
- CIRES, University of Colorado, Boulder, CO, USA
- Department of Chemistry, University of Colorado, Boulder, CO, USA
| | - P L Hayes
- Département de Chimie, Université de Montréal, Montréal, Québec, Canada
| | - A L Robinson
- Center for Atmospheric Particle Studies, Carnegie Mellon University, Pittsburgh, PA, 15213, USA
| | - U Baltensperger
- Paul Scherrer Institute, Laboratory of Atmospheric Chemistry, CH-5232, Villigen, Switzerland
| | - C Astorga
- European Commission Joint Research Centre, Directorate for Energy, Transport and Climate, Sustainable Transport Unit, 21027, Ispra, (VA), Italy
| | - A S H Prévôt
- Paul Scherrer Institute, Laboratory of Atmospheric Chemistry, CH-5232, Villigen, Switzerland.
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9
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Liu S, Li R, Wild RJ, Warneke C, de Gouw JA, Brown SS, Miller SL, Luongo JC, Jimenez JL, Ziemann PJ. Contribution of human-related sources to indoor volatile organic compounds in a university classroom. Indoor Air 2016; 26:925-938. [PMID: 26610063 DOI: 10.1111/ina.12272] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Accepted: 11/18/2015] [Indexed: 05/03/2023]
Abstract
Although significant progress has been made in understanding the sources and chemistry of indoor volatile organic compounds (VOCs) during the past decades, much is unknown about the role of humans in indoor air chemistry. In the spring of 2014, we conducted continuous measurements of VOCs using a proton transfer reaction mass spectrometer (PTR-MS) in a university classroom. Positive matrix factorization (PMF) of the measured VOCs revealed a 'human influence' component, which likely represented VOCs produced from human breath and ozonolysis of human skin lipids. The concentration of the human influence component increased with the number of occupants and decreased with ventilation rate in a similar way to CO2 , with an average contribution of 40% to the measured daytime VOC concentration. In addition, the human skin lipid ozonolysis products were observed to correlate with CO2 and anticorrelate with O3 , suggesting that reactions on human surfaces may be important sources of indoor VOCs and sinks for indoor O3 . Our study suggests that humans can substantially affect VOC composition and oxidative capacity in indoor environments.
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Affiliation(s)
- S Liu
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA
- Department of Chemistry and Biochemistry, University of Colorado, Boulder, CO, USA
| | - R Li
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA
- Department of Atmospheric and Oceanic Sciences, University of Colorado, Boulder, CO, USA
- Chemical Sciences Division, NOAA Earth System Research Laboratory, Boulder, CO, USA
| | - R J Wild
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA
- Chemical Sciences Division, NOAA Earth System Research Laboratory, Boulder, CO, USA
| | - C Warneke
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA
- Chemical Sciences Division, NOAA Earth System Research Laboratory, Boulder, CO, USA
| | - J A de Gouw
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA
- Chemical Sciences Division, NOAA Earth System Research Laboratory, Boulder, CO, USA
| | - S S Brown
- Department of Chemistry and Biochemistry, University of Colorado, Boulder, CO, USA
- Chemical Sciences Division, NOAA Earth System Research Laboratory, Boulder, CO, USA
| | - S L Miller
- Department of Mechanical Engineering, University of Colorado, Boulder, CO, USA
| | - J C Luongo
- Department of Mechanical Engineering, University of Colorado, Boulder, CO, USA
| | - J L Jimenez
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA
- Department of Chemistry and Biochemistry, University of Colorado, Boulder, CO, USA
| | - P J Ziemann
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA
- Department of Chemistry and Biochemistry, University of Colorado, Boulder, CO, USA
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10
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Marais EA, Jacob DJ, Jimenez JL, Campuzano-Jost P, Day DA, Hu W, Krechmer J, Zhu L, Kim PS, Miller CC, Fisher JA, Travis K, Yu K, Hanisco TF, Wolfe GM, Arkinson HL, Pye HOT, Froyd KD, Liao J, McNeill VF. Aqueous-phase mechanism for secondary organic aerosol formation from isoprene: application to the Southeast United States and co-benefit of SO 2 emission controls. Atmos Chem Phys 2016; 16:1603-1618. [PMID: 32742280 PMCID: PMC7394309 DOI: 10.5194/acp-16-1603-2016] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Isoprene emitted by vegetation is an important precursor of secondary organic aerosol (SOA), but the mechanism and yields are uncertain. Aerosol is prevailingly aqueous under the humid conditions typical of isoprene-emitting regions. Here we develop an aqueous-phase mechanism for isoprene SOA formation coupled to a detailed gas-phase isoprene oxidation scheme. The mechanism is based on aerosol reactive uptake coefficients (γ) for water-soluble isoprene oxidation products, including sensitivity to aerosol acidity and nucleophile concentrations. We apply this mechanism to simulation of aircraft (SEAC4RS) and ground-based (SOAS) observations over the Southeast US in summer 2013 using the GEOS-Chem chemical transport model. Emissions of nitrogen oxides (NOx ≡ NO + NO2) over the Southeast US are such that the peroxy radicals produced from isoprene oxidation (ISOPO2) react significantly with both NO (high-NOx pathway) and HO2 (low-NOx pathway), leading to different suites of isoprene SOA precursors. We find a mean SOA mass yield of 3.3 % from isoprene oxidation, consistent with the observed relationship of total fine organic aerosol (OA) and formaldehyde (a product of isoprene oxidation). Isoprene SOA production is mainly contributed by two immediate gas-phase precursors, isoprene epoxydiols (IEPOX, 58% of isoprene SOA) from the low-NOx pathway and glyoxal (28%) from both low- and high-NOx pathways. This speciation is consistent with observations of IEPOX SOA from SOAS and SEAC4RS. Observations show a strong relationship between IEPOX SOA and sulfate aerosol that we explain as due to the effect of sulfate on aerosol acidity and volume. Isoprene SOA concentrations increase as NOx emissions decrease (favoring the low-NOx pathway for isoprene oxidation), but decrease more strongly as SO2 emissions decrease (due to the effect of sulfate on aerosol acidity and volume). The US EPA projects 2013-2025 decreases in anthropogenic emissions of 34% for NOx (leading to 7% increase in isoprene SOA) and 48% for SO2 (35% decrease in isoprene SOA). Reducing SO2 emissions decreases sulfate and isoprene SOA by a similar magnitude, representing a factor of 2 co-benefit for PM2.5 from SO2 emission controls.
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Affiliation(s)
- E A Marais
- School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - D J Jacob
- School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
- Earth and Planetary Sciences, Harvard University, Cambridge, MA, USA
| | - J L Jimenez
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA
- Department of Chemistry and Biochemistry, University of Colorado, Boulder, CO, USA
| | - P Campuzano-Jost
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA
- Department of Chemistry and Biochemistry, University of Colorado, Boulder, CO, USA
| | - D A Day
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA
- Department of Chemistry and Biochemistry, University of Colorado, Boulder, CO, USA
| | - W Hu
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA
- Department of Chemistry and Biochemistry, University of Colorado, Boulder, CO, USA
| | - J Krechmer
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA
- Department of Chemistry and Biochemistry, University of Colorado, Boulder, CO, USA
| | - L Zhu
- School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - P S Kim
- Earth and Planetary Sciences, Harvard University, Cambridge, MA, USA
| | - C C Miller
- Earth and Planetary Sciences, Harvard University, Cambridge, MA, USA
| | - J A Fisher
- School of Chemistry and School of Earth and Environmental Sciences, University of Wollongong, Wollongong, New South Wales, Australia
| | - K Travis
- School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - K Yu
- School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - T F Hanisco
- Atmospheric Chemistry and Dynamics Lab, NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - G M Wolfe
- Atmospheric Chemistry and Dynamics Lab, NASA Goddard Space Flight Center, Greenbelt, MD, USA
- Joint Center for Earth Systems Technology, University of Maryland Baltimore County, Baltimore, MD, USA
| | - H L Arkinson
- Department of Atmospheric and Oceanic Science, University of Maryland, College Park, MD, USA
| | - H O T Pye
- National Exposure Research Laboratory, US EPA, Research Triangle Park, NC, USA
| | - K D Froyd
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA
- Chemical Sciences Division, Earth System Research Laboratory, NOAA, Boulder, Colorado, USA
| | - J Liao
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA
- Chemical Sciences Division, Earth System Research Laboratory, NOAA, Boulder, Colorado, USA
| | - V F McNeill
- Department of Chemical Engineering, Columbia University, New York, New York 10027, USA
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11
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Marais EA, Jacob DJ, Jimenez JL, Campuzano-Jost P, Day DA, Hu W, Krechmer J, Zhu L, Kim PS, Miller CC, Fisher JA, Travis K, Yu K, Hanisco TF, Wolfe GM, Arkinson HL, Pye HOT, Froyd KD, Liao J, McNeill VF. Aqueous-phase mechanism for secondary organic aerosol formation from isoprene: application to the Southeast United States and co-benefit of SO 2 emission controls. Atmos Chem Phys 2016. [PMID: 32742280 DOI: 10.5194/acp16-1603-2016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Isoprene emitted by vegetation is an important precursor of secondary organic aerosol (SOA), but the mechanism and yields are uncertain. Aerosol is prevailingly aqueous under the humid conditions typical of isoprene-emitting regions. Here we develop an aqueous-phase mechanism for isoprene SOA formation coupled to a detailed gas-phase isoprene oxidation scheme. The mechanism is based on aerosol reactive uptake coefficients (γ) for water-soluble isoprene oxidation products, including sensitivity to aerosol acidity and nucleophile concentrations. We apply this mechanism to simulation of aircraft (SEAC4RS) and ground-based (SOAS) observations over the Southeast US in summer 2013 using the GEOS-Chem chemical transport model. Emissions of nitrogen oxides (NOx ≡ NO + NO2) over the Southeast US are such that the peroxy radicals produced from isoprene oxidation (ISOPO2) react significantly with both NO (high-NOx pathway) and HO2 (low-NOx pathway), leading to different suites of isoprene SOA precursors. We find a mean SOA mass yield of 3.3 % from isoprene oxidation, consistent with the observed relationship of total fine organic aerosol (OA) and formaldehyde (a product of isoprene oxidation). Isoprene SOA production is mainly contributed by two immediate gas-phase precursors, isoprene epoxydiols (IEPOX, 58% of isoprene SOA) from the low-NOx pathway and glyoxal (28%) from both low- and high-NOx pathways. This speciation is consistent with observations of IEPOX SOA from SOAS and SEAC4RS. Observations show a strong relationship between IEPOX SOA and sulfate aerosol that we explain as due to the effect of sulfate on aerosol acidity and volume. Isoprene SOA concentrations increase as NOx emissions decrease (favoring the low-NOx pathway for isoprene oxidation), but decrease more strongly as SO2 emissions decrease (due to the effect of sulfate on aerosol acidity and volume). The US EPA projects 2013-2025 decreases in anthropogenic emissions of 34% for NOx (leading to 7% increase in isoprene SOA) and 48% for SO2 (35% decrease in isoprene SOA). Reducing SO2 emissions decreases sulfate and isoprene SOA by a similar magnitude, representing a factor of 2 co-benefit for PM2.5 from SO2 emission controls.
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Affiliation(s)
- E A Marais
- School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - D J Jacob
- School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
- Earth and Planetary Sciences, Harvard University, Cambridge, MA, USA
| | - J L Jimenez
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA
- Department of Chemistry and Biochemistry, University of Colorado, Boulder, CO, USA
| | - P Campuzano-Jost
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA
- Department of Chemistry and Biochemistry, University of Colorado, Boulder, CO, USA
| | - D A Day
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA
- Department of Chemistry and Biochemistry, University of Colorado, Boulder, CO, USA
| | - W Hu
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA
- Department of Chemistry and Biochemistry, University of Colorado, Boulder, CO, USA
| | - J Krechmer
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA
- Department of Chemistry and Biochemistry, University of Colorado, Boulder, CO, USA
| | - L Zhu
- School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - P S Kim
- Earth and Planetary Sciences, Harvard University, Cambridge, MA, USA
| | - C C Miller
- Earth and Planetary Sciences, Harvard University, Cambridge, MA, USA
| | - J A Fisher
- School of Chemistry and School of Earth and Environmental Sciences, University of Wollongong, Wollongong, New South Wales, Australia
| | - K Travis
- School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - K Yu
- School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - T F Hanisco
- Atmospheric Chemistry and Dynamics Lab, NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - G M Wolfe
- Atmospheric Chemistry and Dynamics Lab, NASA Goddard Space Flight Center, Greenbelt, MD, USA
- Joint Center for Earth Systems Technology, University of Maryland Baltimore County, Baltimore, MD, USA
| | - H L Arkinson
- Department of Atmospheric and Oceanic Science, University of Maryland, College Park, MD, USA
| | - H O T Pye
- National Exposure Research Laboratory, US EPA, Research Triangle Park, NC, USA
| | - K D Froyd
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA
- Chemical Sciences Division, Earth System Research Laboratory, NOAA, Boulder, Colorado, USA
| | - J Liao
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA
- Chemical Sciences Division, Earth System Research Laboratory, NOAA, Boulder, Colorado, USA
| | - V F McNeill
- Department of Chemical Engineering, Columbia University, New York, New York 10027, USA
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12
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Fisher JA, Jacob DJ, Travis KR, Kim PS, Marais EA, Miller CC, Yu K, Zhu L, Yantosca RM, Sulprizio MP, Mao J, Wennberg PO, Crounse JD, Teng AP, Nguyen TB, St Clair JM, Cohen RC, Romer P, Nault BA, Wooldridge PJ, Jimenez JL, Campuzano-Jost P, Day DA, Hu W, Shepson PB, Xiong F, Blake DR, Goldstein AH, Misztal PK, Hanisco TF, Wolfe GM, Ryerson TB, Wisthaler A, Mikoviny T. Organic nitrate chemistry and its implications for nitrogen budgets in an isoprene- and monoterpene-rich atmosphere: constraints from aircraft (SEAC 4RS) and ground-based (SOAS) observations in the Southeast US. Atmos Chem Phys 2016; 16:5969-5991. [PMID: 29681921 PMCID: PMC5906813 DOI: 10.5194/acp-16-5969-2016] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Formation of organic nitrates (RONO2) during oxidation of biogenic volatile organic compounds (BVOCs: isoprene, monoterpenes) is a significant loss pathway for atmospheric nitrogen oxide radicals (NOx), but the chemistry of RONO2 formation and degradation remains uncertain. Here we implement a new BVOC oxidation mechanism (including updated isoprene chemistry, new monoterpene chemistry, and particle uptake of RONO2) in the GEOS-Chem global chemical transport model with ∼25 × 25 km2 resolution over North America. We evaluate the model using aircraft (SEAC4RS) and ground-based (SOAS) observations of NOx, BVOCs, and RONO2 from the Southeast US in summer 2013. The updated simulation successfully reproduces the concentrations of individual gas- and particle-phase RONO2 species measured during the campaigns. Gas-phase isoprene nitrates account for 25-50% of observed RONO2 in surface air, and we find that another 10% is contributed by gas-phase monoterpene nitrates. Observations in the free troposphere show an important contribution from long-lived nitrates derived from anthropogenic VOCs. During both campaigns, at least 10% of observed boundary layer RONO2 were in the particle phase. We find that aerosol uptake followed by hydrolysis to HNO3 accounts for 60% of simulated gas-phase RONO2 loss in the boundary layer. Other losses are 20% by photolysis to recycle NOx and 15% by dry deposition. RONO2 production accounts for 20% of the net regional NOx sink in the Southeast US in summer, limited by the spatial segregation between BVOC and NOx emissions. This segregation implies that RONO2 production will remain a minor sink for NOx in the Southeast US in the future even as NOx emissions continue to decline.
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Affiliation(s)
- J A Fisher
- Centre for Atmospheric Chemistry, School of Chemistry, University of Wollongong, Wollongong, NSW, Australia
- School of Earth and Environmental Sciences, University of Wollongong, Wollongong, NSW, Australia
| | - D J Jacob
- Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
- Department of Earth and Planetary Sciences, Harvard University, Cambridge, MA, USA
| | - K R Travis
- Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - P S Kim
- Department of Earth and Planetary Sciences, Harvard University, Cambridge, MA, USA
| | - E A Marais
- Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - C Chan Miller
- Department of Earth and Planetary Sciences, Harvard University, Cambridge, MA, USA
| | - K Yu
- Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - L Zhu
- Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - R M Yantosca
- Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - M P Sulprizio
- Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - J Mao
- Program in Atmospheric and Oceanic Sciences, Princeton University, Princeton, NJ, USA
- Geophysical Fluid Dynamics Laboratory/National Oceanic and Atmospheric Administration, Princeton, NJ, USA
| | - P O Wennberg
- Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA, USA
- Division of Engineering and Applied Science, California Institute of Technology, Pasadena, CA, USA
| | - J D Crounse
- Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA, USA
| | - A P Teng
- Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA, USA
| | - T B Nguyen
- Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA, USA
- Now at Department of Environmental Toxicology, University of California at Davis, Davis, CA, USA
| | - J M St Clair
- Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA, USA
- Now at Atmospheric Chemistry and Dynamics Laboratory, NASA Goddard Space Flight Center, Greenbelt, MD, USA and Joint Center for Earth Systems Technology, University of Maryland Baltimore County, Baltimore, MD, USA
| | - R C Cohen
- Department of Chemistry, University of California at Berkeley, Berkeley, CA, USA
- Department of Earth and Planetary Science, University of California at Berkeley, Berkeley, CA, USA
| | - P Romer
- Department of Chemistry, University of California at Berkeley, Berkeley, CA, USA
| | - B A Nault
- Department of Earth and Planetary Science, University of California at Berkeley, Berkeley, CA, USA
- Now at Department of Chemistry and Biochemistry and Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA
| | - P J Wooldridge
- Department of Chemistry, University of California at Berkeley, Berkeley, CA, USA
| | - J L Jimenez
- Department of Chemistry and Biochemistry, University of Colorado, Boulder, CO, USA
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA
| | - P Campuzano-Jost
- Department of Chemistry and Biochemistry, University of Colorado, Boulder, CO, USA
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA
| | - D A Day
- Department of Chemistry and Biochemistry, University of Colorado, Boulder, CO, USA
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA
| | - W Hu
- Department of Chemistry and Biochemistry, University of Colorado, Boulder, CO, USA
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA
| | - P B Shepson
- Department of Chemistry, Purdue University, West Lafayette, IN, USA
- Department of Earth, Atmospheric and Planetary Sciences, Purdue University, West Lafayette, IN, USA
| | - F Xiong
- Department of Chemistry, Purdue University, West Lafayette, IN, USA
| | - D R Blake
- Department of Chemistry, University of California Irvine, Irvine, CA, USA
| | - A H Goldstein
- Department of Environmental Science, Policy, and Management, University of California at Berkeley, Berkeley, CA, USA
- Department of Civil and Environmental Engineering, University of California at Berkeley, Berkeley, CA, USA
| | - P K Misztal
- Department of Environmental Science, Policy, and Management, University of California at Berkeley, Berkeley, CA, USA
| | - T F Hanisco
- Atmospheric Chemistry and Dynamics Laboratory, NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - G M Wolfe
- Atmospheric Chemistry and Dynamics Laboratory, NASA Goddard Space Flight Center, Greenbelt, MD, USA
- Joint Center for Earth Systems Technology, University of Maryland Baltimore County, Baltimore, MD, USA
| | - T B Ryerson
- Chemical Sciences Division, Earth System Research Lab, National Oceanic and Atmospheric Administration, Boulder, CO, USA
| | - A Wisthaler
- Department of Chemistry, University of Oslo, Oslo, Norway
- Institute for Ion Physics and Applied Physics, University of Innsbruck, Innsbruck, Austria
| | - T Mikoviny
- Department of Chemistry, University of Oslo, Oslo, Norway
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13
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Galán M, Fornaguera C, Ortega P, Calderó G, Lorente R, Jimenez JL, Mata JDL, Muñoz-Fernandez MA, Solans C, Gómez R. Dendronized PLGA nanoparticles with anionic carbosilane dendrons as antiviral agents against HIV infection. RSC Adv 2016. [DOI: 10.1039/c6ra13461k] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
PLGA nanoparticles functionalized with carbosilane anionic dendrons have been prepared. The biocompatibility and HIV activity have been explored in PBMC and HEC-1A cells. The results indicate that these systems are powerful anti-HIV agents.
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14
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Li R, Palm BB, Borbon A, Graus M, Warneke C, Ortega AM, Day DA, Brune WH, Jimenez JL, de Gouw JA. Laboratory studies on secondary organic aerosol formation from crude oil vapors. Environ Sci Technol 2013; 47:12566-12574. [PMID: 24088179 DOI: 10.1021/es402265y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Airborne measurements of aerosol composition and gas phase compounds over the Deepwater Horizon (DWH) oil spill in the Gulf of Mexico in June 2010 indicated the presence of high concentrations of secondary organic aerosol (SOA) formed from organic compounds of intermediate volatility. In this work, we investigated SOA formation from South Louisiana crude oil vapors reacting with OH in a Potential Aerosol Mass flow reactor. We use the dependence of evaporation time on the saturation concentration (C*) of the SOA precursors to separate the contribution of species of different C* to total SOA formation. This study shows consistent results with those at the DWH oil spill: (1) organic compounds of intermediate volatility with C* = 10(5)-10(6) μg m(-3) contribute the large majority of SOA mass formed, and have much larger SOA yields (0.37 for C* = 10(5) and 0.21 for C* = 10(6) μg m(-3)) than more volatile compounds with C*≥10(7) μg m(-3), (2) the mass spectral signature of SOA formed from oxidation of the less volatile compounds in the reactor shows good agreement with that of SOA formed at DWH oil spill. These results also support the use of flow reactors simulating atmospheric SOA formation and aging.
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Affiliation(s)
- R Li
- Department of Atmospheric & Oceanic Sciences, University of Colorado , Boulder, Colorado 80309, United States
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15
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Galan M, Sanchez-Rodriguez J, Cangiotti M, Garcia-Gallego S, Jimenez JL, Gomez R, Ottaviani MF, Munoz-Fernandez MA, de la Mata FJ. Antiviral properties against HIV of water soluble copper carbosilane dendrimers and their EPR characterization. Curr Med Chem 2013; 19:4984-94. [PMID: 22963631 DOI: 10.2174/0929867311209024984] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2012] [Revised: 05/28/2012] [Accepted: 08/01/2012] [Indexed: 11/22/2022]
Abstract
We describe here the use of anionic carbosilane dendrimers to obtain new copper complexes. UV-Vis and a computer aided analysis of the EPR spectra provided information about the coordination modes of copper depending on the nature of the dendrimer and about the geometry and structure of the complexes in solution. Some of these metallo-dendrimers have been tested "in vitro" as antiviral compounds in the inhibition of HIV infection in pre and post-infection treatment.
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Affiliation(s)
- M Galan
- Departamento de Quimica Inorganica, Universidad de Alcala, Campus Universitario. Edificio de Farmacia, 28871 Alcala de Henares, Spain
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16
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Lucero MC, Diaz-Brito V, Murillo BT, Carretero SC, Sala M, Casadesús C, Conde MS, Jimenez JL, Pich J, Arnaiz JA, Leon A, Perez I, Muñoz-Fernández MÁ, Gatell JM, Plana M, Esteban M, Bernaldo de Quiros JC, Garcia, for the RISVAC-02 Study F. Reasons for not participating in a phase 1 preventive HIV vaccine study in a resource-rich country. AIDS Patient Care STDS 2012; 26:379-82. [PMID: 22694172 DOI: 10.1089/apc.2012.0086] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022] Open
Affiliation(s)
| | - Vicens Diaz-Brito
- Department of Infectious Diseases, Hospital Clinic-IDIBAPS, Barcelona, Spain
| | | | | | - Marta Sala
- Department of Infectious Diseases, Hospital Clinic-IDIBAPS, Barcelona, Spain
| | - Cristina Casadesús
- Department of Infectious Diseases, Hospital Clinic-IDIBAPS, Barcelona, Spain
| | | | | | - Judit Pich
- Department of Infectious Diseases, Hospital Clinic-IDIBAPS, Barcelona, Spain
| | - Joan Albert Arnaiz
- Department of Infectious Diseases, Hospital Clinic-IDIBAPS, Barcelona, Spain
| | - Agathe Leon
- Department of Infectious Diseases, Hospital Clinic-IDIBAPS, Barcelona, Spain
| | - Iñaki Perez
- Department of Infectious Diseases, Hospital Clinic-IDIBAPS, Barcelona, Spain
| | | | - Jose M. Gatell
- Department of Infectious Diseases, Hospital Clinic-IDIBAPS, Barcelona, Spain
| | - Montserrat Plana
- Department of Infectious Diseases, Hospital Clinic-IDIBAPS, Barcelona, Spain
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17
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Abstract
Air pollution experienced by expanding urban areas is responsible for serious health effects and death for millions of people every year. Trash burning is a common disposal method in poor areas, yet it is uncontrolled in many countries, and its contribution to air pollution is unclear due to uncertainties in its emissions. Here we develop a new trash burning emission inventory for Mexico City based on inverse socioeconomic levels and recently measured emission factors, and apply a chemistry-transport model to analyze the effects on pollutant concentrations. Trash burning is estimated to emit 25 tons of primary organic aerosols (POA) per day, which is comparable to fossil fuel POA emissions in Mexico City, and causes an increase in average organic aerosol concentrations of ∼0.3 μg m(-3) downtown and up to 2 μg m(-3) in highly populated suburbs near the sources of emission. An evaluation using submicrometer antimony suggests that our emission estimates are reasonable. Mitigation of trash burning could reduce the levels of organic aerosols by 2-40% and those of PM(2.5) by 1-15% over the metropolitan area. The trash burning contributions to carbon monoxide, nitrogen oxides, and volatile organic compounds were found to be very small (<3%), and consequently the contributions to secondary nitrate, sulfate, and secondary organic aerosols are also very small.
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Affiliation(s)
- A Hodzic
- National Center for Atmospheric Research, Boulder, Colorado, USA
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18
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Ng NL, Canagaratna MR, Jimenez JL, Zhang Q, Ulbrich IM, Worsnop DR. Real-time methods for estimating organic component mass concentrations from aerosol mass spectrometer data. Environ Sci Technol 2011; 45:910-916. [PMID: 21186814 DOI: 10.1021/es102951k] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We use results from positive matrix factorization (PMF) analysis of 15 urban aerosol mass spectrometer (AMS) data sets to derive simple methods for estimating major organic aerosol (OA) component concentrations in real time. PMF analysis extracts mass spectral (MS) profiles and mass concentrations for key OA components such as hydrocarbon-like OA (HOA), oxygenated OA (OOA), low-volatility OOA (LV-OOA), semivolatile OOA (SV-OOA), and biomass burning OA (BBOA). The variability in the component MS across all sites is characterized and used to derive standard profiles for real-time estimation of component concentrations. Two methods for obtaining first-order estimates of the HOA and OOA mass concentrations are evaluated. The first approach is the tracer m/z method, in which the HOA and OOA concentrations are estimated from m/z 57 and m/z 44 as follows: HOA ∼ 13.4 × (C(57) - 0.1 × C(44)) and OOA ∼ 6.6 × C(44), where C(i) is the equivalent mass concentration of tracer ion m/z i. The second approach uses a chemical mass balance (CMB) method in which standard HOA and OOA profiles are used as a priori information for calculating their mass concentrations. The HOA and OOA mass concentrations obtained from the first-order estimates are evaluated by comparing with the corresponding PMF results for each site. Both methods reproduce the HOA and OOA concentrations to within ∼30% of the results from detailed PMF analysis at most sites, with the CMB method being slightly better. For hybrid CMB methods, we find that fixing the LV-OOA spectrum and not constraining the other spectra produces the best results.
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Affiliation(s)
- N L Ng
- Aerodyne Research, Inc., Billerica, Massachusetts 01821, United States
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19
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Jimenez JL, Canagaratna MR, Donahue NM, Prevot ASH, Zhang Q, Kroll JH, DeCarlo PF, Allan JD, Coe H, Ng NL, Aiken AC, Docherty KS, Ulbrich IM, Grieshop AP, Robinson AL, Duplissy J, Smith JD, Wilson KR, Lanz VA, Hueglin C, Sun YL, Tian J, Laaksonen A, Raatikainen T, Rautiainen J, Vaattovaara P, Ehn M, Kulmala M, Tomlinson JM, Collins DR, Cubison MJ, Dunlea EJ, Huffman JA, Onasch TB, Alfarra MR, Williams PI, Bower K, Kondo Y, Schneider J, Drewnick F, Borrmann S, Weimer S, Demerjian K, Salcedo D, Cottrell L, Griffin R, Takami A, Miyoshi T, Hatakeyama S, Shimono A, Sun JY, Zhang YM, Dzepina K, Kimmel JR, Sueper D, Jayne JT, Herndon SC, Trimborn AM, Williams LR, Wood EC, Middlebrook AM, Kolb CE, Baltensperger U, Worsnop DR. Evolution of Organic Aerosols in the Atmosphere. Science 2009; 326:1525-9. [PMID: 20007897 DOI: 10.1126/science.1180353] [Citation(s) in RCA: 1053] [Impact Index Per Article: 70.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- J L Jimenez
- Cooperative Institute for Research in the Environmental Sciences and Department of Chemistry and Biochemistry, University of Colorado, Boulder, CO, USA.
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20
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Huffman JA, Docherty KS, Mohr C, Cubison MJ, Ulbrich IM, Ziemann PJ, Onasch TB, Jimenez JL. Chemically-resolved volatility measurements of organic aerosol fom different sources. Environ Sci Technol 2009; 43:5351-5357. [PMID: 19708365 DOI: 10.1021/es803539d] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
A newly modified fast temperature-stepping thermodenuder (TD) was coupled to a High Resolution Time-of-Flight Aerosol Mass Spectrometer for rapid determination of chemically resolved volatility of organic aerosols (OA) emitted from individual sources. The TD-AMS system was used to characterize primary OA (POA) from biomass burning, trash burning surrogates (paper and plastic), and meat cooking as well as chamber-generated secondary OA (SOA) from alpha-pinene and gasoline vapor. Almost all atmospheric models represent POA as nonvolatile, with no allowance for evaporation upon heating or dilution, or condensation upon cooling. Our results indicate that all OAs observed show semivolatile behavior and that most POAs characterized here were at least as volatile as SOA measured in urban environments. Biomass-burning OA (BBOA) exhibited a wide range of volatilities, but more often showed volatility similar to urban OA. Paper-burning resembles some types of BBOA because of its relatively high volatility and intermediate atomic oxygen-to-carbon (O/C) ratio, while meat-cooking OAs (MCOA) have consistently lower volatility than ambient OA. Chamber-generated SOA under the relatively high concentrations used intraditional experiments was significantly more volatile than urban SOA, challenging extrapolation of traditional laboratory volatility measurements to the atmosphere. Most OAs sampled show increasing O/C ratio and decreasing H/C (hydrogen-to-carbon) ratio with temperature, further indicating that more oxygenated OA components are typically less volatile. Future experiments should systematically explore a wider range of mass concentrations to more fully characterize the volatility distributions of these OAs.
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Affiliation(s)
- J A Huffman
- Cooperative Institute for Research in Environmental Sciences (CIRES), Boulder, Colorado, USA
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21
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Johnson KS, Laskin A, Jimenez JL, Shutthanandan V, Molina LT, Salcedo D, Dzepina K, Molina MJ. Comparative analysis of urban atmospheric aerosol by particle-induced X-ray emission (PIXE), proton elastic scattering analysis (PESA), and aerosol mass spectrometry (AMS). Environ Sci Technol 2008; 42:6619-6624. [PMID: 18800539 DOI: 10.1021/es800393e] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
A multifaceted approach to atmospheric aerosol analysis is often desirable in field studies where an understanding of technical comparability among different measurement techniques is essential. Herein, we report quantitative intercomparisons of particle-induced X-ray emission (PIXE) and proton elastic scattering analysis (PESA), performed of fline under a vacuum, with analysis by aerosol mass spectrometry (AMS) carried out in real-time during the MCMA-2003 Field Campaign in the Mexico City Metropolitan Area. Good agreement was observed for mass concentrations of PIXE-measured sulfur (assuming it was dominated by SO4(2-)) and AMS-measured sulfate during most of the campaign. PESA-measured hydrogen mass was separated into sulfate H and organic H mass fractions, assuming the only major contributions were (NH4)2SO4 and organic compounds. Comparison of the organic H mass with AMS organic aerosol measurements indicates that about 75% of the mass of these species evaporated under a vacuum. However approximately 25% of the organics does remain under a vacuum, which is only possible with low-vapor-pressure compounds, and which supports the presence of high-molecular-weight or highly oxidized organics consistent with atmospheric aging. Approximately 10% of the chloride detected by AMS was measured by PIXE, possibly in the form of metal-chloride complexes, while the majority of Cl was likely present as more volatile species including NH4Cl. This is the first comparison of PIXE/PESA and AMS and, to our knowledge, also the first report of PESA hydrogen measurements for urban organic aerosols.
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Affiliation(s)
- K S Johnson
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
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22
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Canagaratna MR, Jayne JT, Jimenez JL, Allan JD, Alfarra MR, Zhang Q, Onasch TB, Drewnick F, Coe H, Middlebrook A, Delia A, Williams LR, Trimborn AM, Northway MJ, DeCarlo PF, Kolb CE, Davidovits P, Worsnop DR. Chemical and microphysical characterization of ambient aerosols with the aerodyne aerosol mass spectrometer. Mass Spectrom Rev 2007; 26:185-222. [PMID: 17230437 DOI: 10.1002/mas.20115] [Citation(s) in RCA: 366] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The application of mass spectrometric techniques to the real-time measurement and characterization of aerosols represents a significant advance in the field of atmospheric science. This review focuses on the aerosol mass spectrometer (AMS), an instrument designed and developed at Aerodyne Research, Inc. (ARI) that is the most widely used thermal vaporization AMS. The AMS uses aerodynamic lens inlet technology together with thermal vaporization and electron-impact mass spectrometry to measure the real-time non-refractory (NR) chemical speciation and mass loading as a function of particle size of fine aerosol particles with aerodynamic diameters between approximately 50 and 1,000 nm. The original AMS utilizes a quadrupole mass spectrometer (Q) with electron impact (EI) ionization and produces ensemble average data of particle properties. Later versions employ time-of-flight (ToF) mass spectrometers and can produce full mass spectral data for single particles. This manuscript presents a detailed discussion of the strengths and limitations of the AMS measurement approach and reviews how the measurements are used to characterize particle properties. Results from selected laboratory experiments and field measurement campaigns are also presented to highlight the different applications of this instrument. Recent instrumental developments, such as the incorporation of softer ionization techniques (vacuum ultraviolet (VUV) photo-ionization, Li+ ion, and electron attachment) and high-resolution ToF mass spectrometers, that yield more detailed information about the organic aerosol component are also described.
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Affiliation(s)
- M R Canagaratna
- Center for Aerosol and Cloud Chemistry, Aerodyne Research, Inc., 45 Manning Rd., Billerica, Massachusetts 01821, USA.
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23
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Bahreini R, Keywood MD, Ng NL, Varutbangkul V, Gao S, Flagan RC, Seinfeld JH, Worsnop DR, Jimenez JL. Measurements of secondary organic aerosol from oxidation of cycloalkenes, terpenes, and m-xylene using an Aerodyne aerosol mass spectrometer. Environ Sci Technol 2005; 39:5674-88. [PMID: 16124302 DOI: 10.1021/es048061a] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
The Aerodyne aerosol mass spectrometer (AMS) was used to characterize physical and chemical properties of secondary organic aerosol (SOA) formed during ozonolysis of cycloalkenes and biogenic hydrocarbons and photo-oxidation of m-xylene. Comparison of mass and volume distributions from the AMS and differential mobility analyzers yielded estimates of "effective" density of the SOA in the range of 0.64-1.45 g/cm3, depending on the particular system. Increased contribution of the fragment at m/z 44, C02+ ion fragment of oxygenated organics, and higher "delta" values, based on ion series analysis of the mass spectra, in nucleation experiments of cycloalkenes suggest greater contribution of more oxygenated molecules to the SOA as compared to those formed under seeded experiments. Dominant negative "delta" values of SOA formed during ozonolysis of biogenics indicates the presence of terpene derivative structures or cyclic or unsaturated oxygenated compounds in the SOA. Evidence of acid-catalyzed heterogeneous chemistry, characterized by greater contribution of higher molecular weight fragments to the SOA and corresponding changes in "delta" patterns, is observed in the ozonolysis of alpha-pinene. Mass spectra of SOA formed during photooxidation of m-xylene exhibit features consistent with the presence of furandione compounds and nitro organics. This study demonstrates that mixtures of SOA compounds produced from similar precursors result in broadly similar AMS mass spectra. Thus, fragmentation patterns observed for biogenic versus anthropogenic SOA may be useful in determining the sources of ambient SOA.
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Affiliation(s)
- R Bahreini
- Department of Environmental Science and Engineering, California Institute of Technology, Mail Code 210-41, 1200 East California Boulevard, Pasadena, California 91125, USA
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24
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De Jose MI, Ramos JT, Alvarez S, Jimenez JL, Muñoz-Fernández MA. Vertical transmission of HIV-1 variants resistant to reverse transcriptase and protease inhibitors. Arch Intern Med 2001; 161:2738-9. [PMID: 11732941 DOI: 10.1001/archinte.161.22.2738] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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25
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Jimenez JL, Punzón C, Navarro J, Muñoz-Fernández MA, Fresno M. Phosphodiesterase 4 inhibitors prevent cytokine secretion by T lymphocytes by inhibiting nuclear factor-kappaB and nuclear factor of activated T cells activation. J Pharmacol Exp Ther 2001; 299:753-9. [PMID: 11602691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023] Open
Abstract
Blockade of phosphodiesterase 4 with rolipram reduced the production of tumor necrosis factor (TNF)-alpha, interleukin (IL)-5, IL-10, and IL-2 but poorly inhibited cell proliferation and interferon-gamma (IFN-gamma) production by activated human T cells. Addition of dibutyryl cAMP mimicked rolipram inhibitions on proliferation, IL-2, TNF-alpha, and IFN-gamma but not on IL-10 or IL-5 production. Moreover, the inhibitory effects of rolipram on proliferation, IFN-gamma, and TNF-alpha but not of IL-10 production can be prevented by a specific protein kinase A inhibitor. Rolipram and pentoxifylline, a nonspecific phosphodiesterase inhibitor, decreased transcription of IL-2 and TNF-alpha promoters in transiently transfected normal T cells. Moreover, they inhibited the activation of nuclear factor-kappaB (NF-kappaB) and nuclear factor of activated T cells (NFAT) and stimulated activator protein-1 (AP-1) and cAMP response element-binding proteins (CREBs). In contrast, dibutyryl cAMP inhibited NF-kappaB but not NFAT activation. Thus, our data indicate that blockade of phosphodiesterase 4 regulates transcription of a particular cytokine through inhibition of NF-kappaB and NFAT, and stimulation of AP-1 and CREB.
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Affiliation(s)
- J L Jimenez
- Centro de Biología, Consejo Superior de Investigaciones Cientificas, Universidad Autónoma de Madrid, Cantoblanco, Madrid, Spain
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26
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Bennett-Guerrero E, Jimenez JL, White WD, D'Amico EB, Baldwin BI, Schwinn DA. Cardiovascular effects of intravenous triiodothyronine in patients undergoing coronary artery bypass graft surgery. A randomized, double-blind, placebo- controlled trial. Duke T3 study group. JAMA 1996; 275:687-92. [PMID: 8594265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
OBJECTIVE To test the hypothesis that triiodothyronine (T(3)) administration improves hemodynamic variables and decreases inotropic drug requirements in cardiac surgery patients. DESIGN Prospective, randomized, double-blind, placebo-controlled trial. SETTING Tertiary care medical center. PATIENTS A total of 211 patients undergoing coronary artery surgery at high risk for requiring inotropic drug support. INTERVENTION At release of aortic cross-clamp, patients were randomized to an intravenous infusion of T(3) (0.8 microg/kg followed by 0.12 microg.kg(-1).h(-1) for 6 hours), dopamine (positive control, 5 microg.kg(-1).min(-1) for 6 hours) or placebo. MAIN OUTCOME MEASURES Perioperative hemodynamic variables, inotropic support requirements, and serum T(3) concentrations. RESULTS Mean+/-SEM free T(3) serum concentrations decreased significantly during cardiopulmonary bypass in all groups (from 0.0035+/-0.0001 nmol/L [0.23+/-0.01 ng/dL] to 0.001+/-0.0001 nmol/L [0.7+/- 0.00 ng/dL]; P=.001) and increased to 0.0133+/-0.0004 nmol/L [0.87+/-0.03 ng/dL] (twice normal range; P<.001) following initiation of intravenous T(3). Intravenous T(3) did not change hemodynamic variables or inotropic drug requirements; however, heart rate increased (P<.001), and a trend toward decreased use of inotropic agents was demonstrated in the dopamine group. CONCLUSIONS Triiodothyronine administration prevents decreases in serum thyroid hormone concentrations associated with cardiopulmonary bypass. Intravenous T(3) does not have dramatic effects on hemodynamic variables in this setting as has been previously suggested. Although mild effects on myocardial performance may exist, we cannot recommend at this time the routine use of intravenous T(3) as an inotropic agent in patients undergoing coronary artery bypass graft surgery.
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Affiliation(s)
- E Bennett-Guerrero
- Department of Anesthesiology, Duke University Medical Center, Durham, NC, USA
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27
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Jimenez JL, Mendez EE, Li X, Wang WI. Intrinsic bistability by charge accumulation in an L-valley state in GaSb-AlSb resonant-tunneling diodes. Phys Rev B Condens Matter 1995; 52:R5495-R5498. [PMID: 9981813 DOI: 10.1103/physrevb.52.r5495] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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28
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Bennett-Guerrero E, Jimenez JL, DʼAmico EB, White WD, Baldwin B, Phillips SA, Clements FM, Van Trigt P, Schwinn DA. EFFECT OF TRIIODOTHYRONINE ON HEMODYNAMICS AND POST-OPERATIVE SUPPORT IN PATIENTS UNDERGOING CABG. Anesth Analg 1995. [DOI: 10.1213/00000539-199504001-00011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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29
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Jimenez JL, Mendez EE, Li X, Wang WI. Resonant tunneling of L-valley electrons in GaSb-based double-barrier heterostructures. Phys Rev B Condens Matter 1995; 51:7938-7941. [PMID: 9977394 DOI: 10.1103/physrevb.51.7938] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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30
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Abstract
The trans-cerebral v. have long been described, but there is little or no knowledge of their function and dysfunction. They are the site of fundamental interchange across the blood-brain barrier, a unique process within the organism. Two systems can be structurally distinguished: the venous system draining the white matter and the trans-cerebral anastomotic system. The former seems to be associated with the nutrition and drainage of the parenchyma, and is rendered visible at angiography by anatomic variations based on developmental venous anomalies. The anastomotic trans-cerebral ventriculo-cortical system seems concerned with the regulation of reabsorption of the cerebrospinal fluid. It is visualized only in exceptional situations where an increased flow (arteriovenous shunt) is combined with obstruction of the normal routes of venous drainage and collateral circulation. It usually functions in the ventriculo-cortical direction. No specific dysfunction of this system is currently recognized.
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Affiliation(s)
- J L Jimenez
- Laboratoire de Morphologie in vivo, Hôpital du Kremlin-Bicêtre, France
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31
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Hernandez ER, Jimenez JL, Payne DW, Adashi EY. Adrenergic regulation of ovarian androgen biosynthesis is mediated via beta 2-adrenergic theca-interstitial cell recognition sites. Endocrinology 1988; 122:1592-602. [PMID: 2831035 DOI: 10.1210/endo-122-4-1592] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Acting alone or in concert with pituitary gonadotropins, catecholamines have recently been shown to enhance androgen production by ovarian theca-interstitial cells. It is the objective of the in vitro studies reported herein to further characterize this catecholaminergic activity as well as to type and subtype the putative adrenergic recognition sites mediating this phenomenon. Treatment of collagenase-processed whole ovarian dispersates or highly enriched (greater than 90%) theca-interstitial cells from immature rats with norepinephrine (10(-6) M) resulted in a 2.0-fold increment in the accumulation of androsterone (3 alpha-hydroxy-5 alpha-androstane-17-one), the main androgenic steroid identified in culture medium by HPLC. Qualitatively similar stimulation was obtained using beta (isoproterenol)- but not alpha (methoxamine)-selective adrenergic agonists. Moreover, combined treatment with both norepinephrine (10(-6) M) and hCG (1 ng/ml) unmasked a synergistic interaction subject to stereospecific blockade by beta (propranolol)- but not alpha (phentolamine)-selective adrenergic antagonists. Further probing with subtype-selective adrenergic ligands revealed terbutaline (a beta 2-selective agonist) to enhance androgen biosynthesis, with dobutamine (a beta 1-selective agonist) having little or no effect. Moreover, a beta 2 (ICI-118406)- but not a beta 1 (ICI-89406)-selective adrenergic antagonist yielded dose-dependent inhibition of the isoproterenol effect. Unaccounted for by either enhanced cellular growth or an alteration of the overall steroidogenic pattern, catecholaminergically stimulated androgen biosynthesis proved time and dose dependent but independent of the hCG dose (0.1-10 ng/ml) employed. Binding of [125I]iodocyanopindolol to highly enriched theca-interstitial cells proved stereoselective and saturable, displaying a single class (Hill coefficient = 0.96 +/- 0.01) of high affinity (Kd = 5.6 X 10(-11) M), low capacity (1219 +/- 317 sites/cell) binding sites. The rank order of competitive potencies of selective adrenergic ligands (beta 2 greater than beta 1 greater than alpha), was consistent with a beta 2-adrenergic receptor subtype. Taken together, these findings suggest that catecholaminergic stimulation of ovarian androgen biosynthesis is mediated via beta 2-adrenergic recognition sites, the role of which may now be studied.
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Affiliation(s)
- E R Hernandez
- Department of Obstetrics, Gynecology, University of Maryland School of Medicine, Baltimore 21201
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Blanco R, Pesquera L, Jimenez JL. Classical extended charge subjected to linear forces and Rayleigh-Jeans radiation. Int J Clin Exp Med 1986; 34:452-462. [PMID: 9957163 DOI: 10.1103/physrevd.34.452] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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