Chemical composition and redox activity of PM0.25 near Los Angeles International Airport and comparisons to an urban traffic site

Farimah Shirmohammadi, Christopher Lovett, Mohammad Hossein Sowlat, Amirhosein Mousavi, Vishal Verma, Martin M. Shafer, James J. Schauer, Constantinos Sioutas

Research output: Research - peer-reviewArticle

Abstract

To investigate the relative impacts of emissions from Los Angeles International Airport (LAX), as well as the impacts of traffic emissions from freeways, on the oxidative potential of particulate matter (PM), PM0.25 were collected at two urban background locations in Los Angeles. Redox activity of the PM samples was measured by means of an in vitro alveolar macrophage assay that quantifies the formation of reactive oxygen species (ROS) in cells, and detailed chemical analyses were performed to determine the speciated chemical composition of collected PM. A molecular marker-based chemical mass balance (MM-CMB) model was applied to estimate the relative contributions from the following primary sources to the organic carbon (OC) component of PM: mobile sources (combined gasoline and diesel vehicles), wood smoke, vegetative detritus, road dust and ship emissions. A source profile of aircraft emissions was not included in the model; however its contribution was estimated from un-apportioned primary OC in the MM-CMB model (“other OC”) after accounting for the contribution of secondary organic carbon (SOC) to OC. The contribution of mobile sources to OC was 82% and 28% at the central Los Angeles site (freeway emissions) and the LAX site, respectively. The estimated contribution of aircraft emissions to PM0.25 OC was 36% at the LAX site. ROS activity levels showed little spatial variability, with no statistically significant difference between the averages observed at LAX (24.75 ± 4.01 μg Zymosan/m3) and central Los Angeles (27.77 ± 2 0.32 μg Zymosan/m3), suggesting similar levels of inhalation exposure to redox active species of PM0.25. A multiple linear regression analysis indicated that the variability in ROS activity is best explained by the chemical markers of major identified sources: EC emitted by traffic, and sulfur, considered in our study as a potential tracer of aircraft emissions, with statistically significantly higher concentrations of sulfur at the LAX site (p < 0.001).

LanguageEnglish (US)
Pages1336-1346
Number of pages11
JournalScience of the Total Environment
Volume610-611
DOIs
StatePublished - Jan 1 2018

Fingerprint

airport
particulate matter
chemical composition
organic carbon
urban traffic
comparison
Particulate Matter
Organic carbon
Airports
Chemical analysis
Oxidation-Reduction
aircraft emission
marker
reactive oxygen species
Reactive Oxygen Species
Aircraft
Oxygen
chemical mass balance
motorway
sulfur

Keywords

  • Aircraft emissions
  • Oxidative potential
  • PM
  • Ultrafine particles
  • Vehicle exhaust emissions

ASJC Scopus subject areas

  • Environmental Engineering
  • Environmental Chemistry
  • Waste Management and Disposal
  • Pollution

Cite this

Chemical composition and redox activity of PM0.25 near Los Angeles International Airport and comparisons to an urban traffic site. / Shirmohammadi, Farimah; Lovett, Christopher; Sowlat, Mohammad Hossein; Mousavi, Amirhosein; Verma, Vishal; Shafer, Martin M.; Schauer, James J.; Sioutas, Constantinos.

In: Science of the Total Environment, Vol. 610-611, 01.01.2018, p. 1336-1346.

Research output: Research - peer-reviewArticle

Shirmohammadi, Farimah ; Lovett, Christopher ; Sowlat, Mohammad Hossein ; Mousavi, Amirhosein ; Verma, Vishal ; Shafer, Martin M. ; Schauer, James J. ; Sioutas, Constantinos. / Chemical composition and redox activity of PM0.25 near Los Angeles International Airport and comparisons to an urban traffic site. In: Science of the Total Environment. 2018 ; Vol. 610-611. pp. 1336-1346
@article{b8e52c1778664949ac0ee85e8664e05a,
title = "Chemical composition and redox activity of PM0.25 near Los Angeles International Airport and comparisons to an urban traffic site",
abstract = "To investigate the relative impacts of emissions from Los Angeles International Airport (LAX), as well as the impacts of traffic emissions from freeways, on the oxidative potential of particulate matter (PM), PM0.25 were collected at two urban background locations in Los Angeles. Redox activity of the PM samples was measured by means of an in vitro alveolar macrophage assay that quantifies the formation of reactive oxygen species (ROS) in cells, and detailed chemical analyses were performed to determine the speciated chemical composition of collected PM. A molecular marker-based chemical mass balance (MM-CMB) model was applied to estimate the relative contributions from the following primary sources to the organic carbon (OC) component of PM: mobile sources (combined gasoline and diesel vehicles), wood smoke, vegetative detritus, road dust and ship emissions. A source profile of aircraft emissions was not included in the model; however its contribution was estimated from un-apportioned primary OC in the MM-CMB model (“other OC”) after accounting for the contribution of secondary organic carbon (SOC) to OC. The contribution of mobile sources to OC was 82% and 28% at the central Los Angeles site (freeway emissions) and the LAX site, respectively. The estimated contribution of aircraft emissions to PM0.25 OC was 36% at the LAX site. ROS activity levels showed little spatial variability, with no statistically significant difference between the averages observed at LAX (24.75 ± 4.01 μg Zymosan/m3) and central Los Angeles (27.77 ± 2 0.32 μg Zymosan/m3), suggesting similar levels of inhalation exposure to redox active species of PM0.25. A multiple linear regression analysis indicated that the variability in ROS activity is best explained by the chemical markers of major identified sources: EC emitted by traffic, and sulfur, considered in our study as a potential tracer of aircraft emissions, with statistically significantly higher concentrations of sulfur at the LAX site (p < 0.001).",
keywords = "Aircraft emissions, Oxidative potential, PM, Ultrafine particles, Vehicle exhaust emissions",
author = "Farimah Shirmohammadi and Christopher Lovett and Sowlat, {Mohammad Hossein} and Amirhosein Mousavi and Vishal Verma and Shafer, {Martin M.} and Schauer, {James J.} and Constantinos Sioutas",
year = "2018",
month = "1",
doi = "10.1016/j.scitotenv.2017.08.239",
volume = "610-611",
pages = "1336--1346",
journal = "Science of the Total Environment",
issn = "0048-9697",
publisher = "Elsevier",

}

TY - JOUR

T1 - Chemical composition and redox activity of PM0.25 near Los Angeles International Airport and comparisons to an urban traffic site

AU - Shirmohammadi,Farimah

AU - Lovett,Christopher

AU - Sowlat,Mohammad Hossein

AU - Mousavi,Amirhosein

AU - Verma,Vishal

AU - Shafer,Martin M.

AU - Schauer,James J.

AU - Sioutas,Constantinos

PY - 2018/1/1

Y1 - 2018/1/1

N2 - To investigate the relative impacts of emissions from Los Angeles International Airport (LAX), as well as the impacts of traffic emissions from freeways, on the oxidative potential of particulate matter (PM), PM0.25 were collected at two urban background locations in Los Angeles. Redox activity of the PM samples was measured by means of an in vitro alveolar macrophage assay that quantifies the formation of reactive oxygen species (ROS) in cells, and detailed chemical analyses were performed to determine the speciated chemical composition of collected PM. A molecular marker-based chemical mass balance (MM-CMB) model was applied to estimate the relative contributions from the following primary sources to the organic carbon (OC) component of PM: mobile sources (combined gasoline and diesel vehicles), wood smoke, vegetative detritus, road dust and ship emissions. A source profile of aircraft emissions was not included in the model; however its contribution was estimated from un-apportioned primary OC in the MM-CMB model (“other OC”) after accounting for the contribution of secondary organic carbon (SOC) to OC. The contribution of mobile sources to OC was 82% and 28% at the central Los Angeles site (freeway emissions) and the LAX site, respectively. The estimated contribution of aircraft emissions to PM0.25 OC was 36% at the LAX site. ROS activity levels showed little spatial variability, with no statistically significant difference between the averages observed at LAX (24.75 ± 4.01 μg Zymosan/m3) and central Los Angeles (27.77 ± 2 0.32 μg Zymosan/m3), suggesting similar levels of inhalation exposure to redox active species of PM0.25. A multiple linear regression analysis indicated that the variability in ROS activity is best explained by the chemical markers of major identified sources: EC emitted by traffic, and sulfur, considered in our study as a potential tracer of aircraft emissions, with statistically significantly higher concentrations of sulfur at the LAX site (p < 0.001).

AB - To investigate the relative impacts of emissions from Los Angeles International Airport (LAX), as well as the impacts of traffic emissions from freeways, on the oxidative potential of particulate matter (PM), PM0.25 were collected at two urban background locations in Los Angeles. Redox activity of the PM samples was measured by means of an in vitro alveolar macrophage assay that quantifies the formation of reactive oxygen species (ROS) in cells, and detailed chemical analyses were performed to determine the speciated chemical composition of collected PM. A molecular marker-based chemical mass balance (MM-CMB) model was applied to estimate the relative contributions from the following primary sources to the organic carbon (OC) component of PM: mobile sources (combined gasoline and diesel vehicles), wood smoke, vegetative detritus, road dust and ship emissions. A source profile of aircraft emissions was not included in the model; however its contribution was estimated from un-apportioned primary OC in the MM-CMB model (“other OC”) after accounting for the contribution of secondary organic carbon (SOC) to OC. The contribution of mobile sources to OC was 82% and 28% at the central Los Angeles site (freeway emissions) and the LAX site, respectively. The estimated contribution of aircraft emissions to PM0.25 OC was 36% at the LAX site. ROS activity levels showed little spatial variability, with no statistically significant difference between the averages observed at LAX (24.75 ± 4.01 μg Zymosan/m3) and central Los Angeles (27.77 ± 2 0.32 μg Zymosan/m3), suggesting similar levels of inhalation exposure to redox active species of PM0.25. A multiple linear regression analysis indicated that the variability in ROS activity is best explained by the chemical markers of major identified sources: EC emitted by traffic, and sulfur, considered in our study as a potential tracer of aircraft emissions, with statistically significantly higher concentrations of sulfur at the LAX site (p < 0.001).

KW - Aircraft emissions

KW - Oxidative potential

KW - PM

KW - Ultrafine particles

KW - Vehicle exhaust emissions

UR - http://www.scopus.com/inward/record.url?scp=85028369874&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85028369874&partnerID=8YFLogxK

U2 - 10.1016/j.scitotenv.2017.08.239

DO - 10.1016/j.scitotenv.2017.08.239

M3 - Article

VL - 610-611

SP - 1336

EP - 1346

JO - Science of the Total Environment

T2 - Science of the Total Environment

JF - Science of the Total Environment

SN - 0048-9697

ER -