Regional composition of PM2.5 aerosols measured at urban, rural and “background” sites in the Tennessee valley

Tanner, Roger L.; Parkhurst, William J.; Valente, Myra L.; Phillips, W. D.

doi:10.1016/j.atmosenv.2004.03.023

Cited by 48 publications

(18 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As compared to other major cities in the world, Toronto's BC concentrations are low: Winter averages have been observed to be 6.3 µg/m 3 , 12.2 µg/m 3 , and 2.4 µg/m 3 in Beijing (He et al 2001), Athens (Valaoraas et al 1988), and Chattanooga, Tennessee (Tanner et al 2004), respectively. The ratio of OC/EC varied seasonally, suggesting less material was available for coating of BC during winter months, consistent with less photochemical production of secondary organic compounds during the winter.…”

Section: Typical Black Carbon Concentrationsmentioning

confidence: 94%

Mass Absorption Cross-Section of Ambient Black Carbon Aerosol in Relation to Chemical Age

Knox

Evans

Brook

et al. 2009

Aerosol Science and Technology

147

109

View full text Add to dashboard Cite

Three differing techniques were used to measure ambient black carbon (BC) aerosols in downtown Toronto through 20 December 2006 to 23 January 2007. These techniques were thermal analysis, as performed by a Sunset Labs OCEC Analyzer (OCEC); light attenuation, as performed by an Aethalometer (AE); and photoacoustic analysis, as performed by a Photoacoustic Instrument (PA). These measurements of ambient PM 2.5 were used to investigate the effects of coating thickness on BC Mass Absorption Cross-section (MAC). MAC values were determined by comparing 880 nm and 370 nm AE measurements and PA measurements of b abs (absorption coefficient, Mm -1 ) to the OCEC measurements. Based on mass size distributions and supporting criteria, the PM 2.5 was classified as fresh, semi-aged, or aged. The average MAC values in these categories, based on the PA measurements, were 9.3 ± 1.8, 9.9 ± 2.0, and 9.3 ± 2.2 m 2 /g (mean ± standard deviation), respectively, suggesting that any difference in coating thickness as a result of aging, on the time scale observed, did not produce a difference in MAC. In a second type of experiment, a thermodenuder was installed upstream of the AE, PA, and OCEC and samples were heated to 340 • C in order to evaporate volatile and semi-volatile components within the coating. Based on the PA measurements, the average MAC values of these heated samples, for the fresh, semi-aged, and aged categories were 7.7 ± 2.2, 6.9 ± 2.2, and 9.1 ± 2.0 m 2 /g, respectively. Similar differences in MAC were also observed by the AE. The decrease in MAC in the fresh and semi-aged samples was interpreted in terms of the degree of coating of the PM 2.5 . Results agreed well with predictions made by absorption amplification theory and had ramifications for calibration of filter-base attenuation and photoacoustic instruments.

show abstract

Section: Typical Black Carbon Concentrationsmentioning

confidence: 94%

Mass Absorption Cross-Section of Ambient Black Carbon Aerosol in Relation to Chemical Age

Knox

Evans

Brook

et al. 2009

Aerosol Science and Technology

147

109

View full text Add to dashboard Cite

show abstract

“…Urbanicity was chosen for further analysis due to the possible compositional differences in PM 2.5 between more urban and less urban areas [52-54], while health insurance was chosen for further examination due to the possible reporting differences in respiratory outcomes for adults with and without insurance. For these sensitivity analyses, interaction terms between PM 2.5 and urbanization and health insurance were examined in logistic models for the overall sample and for race/ethnicity groups.…”

Section: Methodsmentioning

confidence: 99%

Exposures to fine particulate air pollution and respiratory outcomes in adults using two national datasets: a cross-sectional study

Nachman

Parker

2012

Environ Health

View full text Add to dashboard Cite

BackgroundRelationships between chronic exposures to air pollution and respiratory health outcomes have yet to be clearly articulated for adults. Recent data from nationally representative surveys suggest increasing disparity by race/ethnicity regarding asthma-related morbidity and mortality. The objectives of this study are to evaluate the relationship between annual average ambient fine particulate matter (PM2.5) concentrations and respiratory outcomes for adults using modeled air pollution and health outcome data and to examine PM2.5 sensitivity across race/ethnicity.MethodsRespondents from the 2002-2005 National Health Interview Survey (NHIS) were linked to annual kriged PM2.5 data from the USEPA AirData system. Logistic regression was employed to investigate increases in ambient PM2.5 concentrations and self-reported prevalence of respiratory outcomes including asthma, sinusitis and chronic bronchitis. Models included health, behavioral, demographic and resource-related covariates. Stratified analyses were conducted by race/ethnicity.ResultsOf nearly 110,000 adult respondents, approximately 8,000 and 4,000 reported current asthma and recent attacks, respectively. Overall, odds ratios (OR) for current asthma (0.97 (95% Confidence Interval: 0.87-1.07)) and recent attacks (0.90 (0.78-1.03)) did not suggest an association with a 10 μg/m3 increase in PM2.5. Stratified analyses revealed significant associations for non-Hispanic blacks [OR = 1.73 (1.17-2.56) for current asthma and OR = 1.76 (1.07-2.91) for recent attacks] but not for Hispanics and non-Hispanic whites. Significant associations were observed overall (1.18 (1.08-1.30)) and in non-Hispanic whites (1.31 (1.18-1.46)) for sinusitis, but not for chronic bronchitis.ConclusionsNon-Hispanic blacks may be at increased sensitivity of asthma outcomes from PM2.5 exposure. Increased chronic PM2.5 exposures in adults may contribute to population sinusitis burdens.

show abstract

“…77 At eastern U.S. locations, the aerosol was characterized by higher sulfate and significant amounts of SOA in the summer, when photochemical activity peaks, with higher overall OC (mostly primary), nitrate, and EC in the winter months because of lower mixing heights and cooler temperatures. 90,163,170,[173][174][175][176][177][178][179][180] In Atlanta, the highest concentrations were observed in the summer, with sulfate typically being the largest contributor, although OC was typically the second most abundant species with a relatively flat seasonal trend. 163,173 OC consisted of primary and SOA with up to 46% of the OC being SOA.…”

Section: Characterization Of Ambient Pm Annual or Study Period And Damentioning

confidence: 99%

Key Scientific Findings and Policy- and Health-Relevant Insights from the U.S. Environmental Protection Agency’s Particulate Matter Supersites Program and Related Studies: An Integration and Synthesis of Results

Solomon

Hopke

Froines

et al. 2008

JAWMA

View full text Add to dashboard Cite

In 1998, the U.S. Environmental Protection Agency (EPA) initiated a major air quality program known as the Particulate Matter (PM) Supersites Program. The Supersites Program was a multiyear, $27 million air quality monitoring program consisting of eight regional air quality projects located throughout the United States, each with differing atmospheric pollution conditions resulting from variations in source emissions and meteorology. The overall goal of the program was to elucidate source-receptor relationships and atmospheric processes leading to PM accumulation on urban and regional scales; thus providing the scientific underpinning for modeling and data analysis efforts to support State Implementation Plans and more effective risk management approaches for PM. The program had three main objectives: (1) conduct methods development and evaluation, (2) characterize ambient PM, and (3) support health effects and exposure research. This paper provides a synthesis of key scientific findings from the Supersites Program and related studies. EPA developed 16 science/policy-relevant questions in conjunction with state and other federal agencies, Regional Planning Organizations, and the private sector. These questions were addressed to the extent possible, even given the vast amount of new information available from the Supersites Program, in a series of papers published as a special issue of the Journal of Air & Waste Management Association (February 2008).This synthesis also includes discussions of: (1) initial Supersites Program support for air quality management efforts in specific locations throughout the United States;(2) selected policy-relevant insights, based on atmospheric sciences findings, useful to air quality managers and decision makers planning emissions management strategies to address current and future PM National Ambient Air Quality Standards (NAAQS) and network planning and implementation; (3) selected health-relevant insights interpreted from atmospheric sciences findings in light of future directions for health and exposure scientists planning studies of the effects of PM on human health; and (4) selected knowledge gaps to guide future research. Finally, given the scope and depth of research and findings from the Supersites Program, this paper provides a reference source so readers can glean a general understanding of the overall research conducted and its policy-relevant insights. Supporting details for the results presented are available through the cited references. An annotated table of contents allows readers to easily find specific subject matter within the text. IMPLICATIONSOver 400 peer-reviewed journal articles and likely more than 1000 presentations resulted from the research conducted through EPA's PM Supersites Program. From the start, the program was developed with a policy focusproviding new information on the accumulation and sources of PM in air on urban and regional scales that might allow for the development of more effective approaches to reducing ambient concentrations of PM to...

show abstract

Regional composition of PM2.5 aerosols measured at urban, rural and “background” sites in the Tennessee valley

Cited by 48 publications

References 13 publications

Mass Absorption Cross-Section of Ambient Black Carbon Aerosol in Relation to Chemical Age

Mass Absorption Cross-Section of Ambient Black Carbon Aerosol in Relation to Chemical Age

Exposures to fine particulate air pollution and respiratory outcomes in adults using two national datasets: a cross-sectional study

Key Scientific Findings and Policy- and Health-Relevant Insights from the U.S. Environmental Protection Agency’s Particulate Matter Supersites Program and Related Studies: An Integration and Synthesis of Results

Contact Info

Product

Resources

About