Abstract
Discussions of excess mortality and morbidity from exposure to urban aerosol particles typically invoke the now 20-year-old trimodal aerosol paradigm proposed by Whitby to explain the structure and behavior of ambient aerosol volume and its major constituent, sulfate. However, this paradigm largely ignores the primary high-temperature combustion (HTC) components of the urban aerosol, which contribute minor amounts of the aerosol mass, but carry the bulk of the particulate toxins and numbers of aerosol particles. Studies encompassing the analyses of > 100 size distributions of important intrinsic tracers of primary particles from HTC sources collected over the past decade in various environments show that urban aerosol contains a complex mixture of physically-discrete fresh and aged, primary particle populations from a variety of sources. Furthermore, whereas the behavior of fine-particulate aerosol mass and sulfate was described in terms of coagulation and accumulation aerosol scavenging of new secondary sulfate nuclei, studies reviewed herein suggest that the behavior of primary aerosol is mediated more by hygroscopic growth and cloud processing, accompanied by oxidation of SO2 on wet particles and droplets. We conclude that the distribution of airborne particulate toxins and their atmospheric behavior is far more complex than commonly conceptualized on the basis of the classical trimodal model, and we develop an extended paradigm in which the focus is on the primary accumulation aerosol.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 2547-2555 |
| Number of pages | 9 |
| Journal | Environmental Science and Technology |
| Volume | 32 |
| Issue number | 17 |
| DOIs | |
| State | Published - Sep 1 1998 |
| Externally published | Yes |
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ASJC Scopus subject areas
- Environmental Science(all)
- Environmental Chemistry
- Environmental Engineering
Cite this
Where do particulate toxins reside? An improved paradigm for the structure and dynamics of the urban mid-Atlantic aerosol. / Ondov, John M.; Wexler, Anthony S.
In: Environmental Science and Technology, Vol. 32, No. 17, 01.09.1998, p. 2547-2555.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Where do particulate toxins reside? An improved paradigm for the structure and dynamics of the urban mid-Atlantic aerosol
AU - Ondov, John M.
AU - Wexler, Anthony S.
PY - 1998/9/1
Y1 - 1998/9/1
N2 - Discussions of excess mortality and morbidity from exposure to urban aerosol particles typically invoke the now 20-year-old trimodal aerosol paradigm proposed by Whitby to explain the structure and behavior of ambient aerosol volume and its major constituent, sulfate. However, this paradigm largely ignores the primary high-temperature combustion (HTC) components of the urban aerosol, which contribute minor amounts of the aerosol mass, but carry the bulk of the particulate toxins and numbers of aerosol particles. Studies encompassing the analyses of > 100 size distributions of important intrinsic tracers of primary particles from HTC sources collected over the past decade in various environments show that urban aerosol contains a complex mixture of physically-discrete fresh and aged, primary particle populations from a variety of sources. Furthermore, whereas the behavior of fine-particulate aerosol mass and sulfate was described in terms of coagulation and accumulation aerosol scavenging of new secondary sulfate nuclei, studies reviewed herein suggest that the behavior of primary aerosol is mediated more by hygroscopic growth and cloud processing, accompanied by oxidation of SO2 on wet particles and droplets. We conclude that the distribution of airborne particulate toxins and their atmospheric behavior is far more complex than commonly conceptualized on the basis of the classical trimodal model, and we develop an extended paradigm in which the focus is on the primary accumulation aerosol.
AB - Discussions of excess mortality and morbidity from exposure to urban aerosol particles typically invoke the now 20-year-old trimodal aerosol paradigm proposed by Whitby to explain the structure and behavior of ambient aerosol volume and its major constituent, sulfate. However, this paradigm largely ignores the primary high-temperature combustion (HTC) components of the urban aerosol, which contribute minor amounts of the aerosol mass, but carry the bulk of the particulate toxins and numbers of aerosol particles. Studies encompassing the analyses of > 100 size distributions of important intrinsic tracers of primary particles from HTC sources collected over the past decade in various environments show that urban aerosol contains a complex mixture of physically-discrete fresh and aged, primary particle populations from a variety of sources. Furthermore, whereas the behavior of fine-particulate aerosol mass and sulfate was described in terms of coagulation and accumulation aerosol scavenging of new secondary sulfate nuclei, studies reviewed herein suggest that the behavior of primary aerosol is mediated more by hygroscopic growth and cloud processing, accompanied by oxidation of SO2 on wet particles and droplets. We conclude that the distribution of airborne particulate toxins and their atmospheric behavior is far more complex than commonly conceptualized on the basis of the classical trimodal model, and we develop an extended paradigm in which the focus is on the primary accumulation aerosol.
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U2 - 10.1021/es971067y
DO - 10.1021/es971067y
M3 - Article
AN - SCOPUS:0032168418
VL - 32
SP - 2547
EP - 2555
JO - Environmental Science & Technology
JF - Environmental Science & Technology
SN - 0013-936X
IS - 17
ER -