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The generation of diesel exhaust particle aerosols from a bulk source in an aerodynamic size range similar to atmospheric particles.

Cooney DJ, Hickey AJ - Int J Nanomedicine (2008)

Bottom Line: Inertial impaction data indicated that the particle size distributions of the generated aerosols were trimodal, with count median aerodynamic diameters less than 100 nm.Scanning electron microscopy of deposited particles showed tightly aggregated particles, as would be expected from an evaporative process.Chemical analysis indicated that there were no major changes in the mass proportion of 2 specific aromatic hydrocarbons (benzo[a]pyrene and benzo[k]fluoranthene) in the particles resulting from the aerosolization process.

View Article: PubMed Central - PubMed

Affiliation: Department of Biomedical Engineering, University of North Carolina, Chapel Hill, NC, USA. cooneyinsf@gmail.com

ABSTRACT
The influence of diesel exhaust particles (DEP) on the lungs and heart is currently a topic of great interest in inhalation toxicology. Epidemiological data and animal studies have implicated airborne particulate matter and DEP in increased morbidity and mortality due to a number of cardiopulmonary diseases including asthma, chronic obstructive pulmonary disorder, and lung cancer. The pathogeneses of these diseases are being studied using animal models and cell culture techniques. Real-time exposures to freshly combusted diesel fuel are complex and require significant infrastructure including engine operations, dilution air, and monitoring and control of gases. A method of generating DEP aerosols from a bulk source in an aerodynamic size range similar to atmospheric DEP would be a desirable and useful alternative. Metered dose inhaler technology was adopted to generate aerosols from suspensions of DEP in the propellant hydrofluoroalkane 134a. Inertial impaction data indicated that the particle size distributions of the generated aerosols were trimodal, with count median aerodynamic diameters less than 100 nm. Scanning electron microscopy of deposited particles showed tightly aggregated particles, as would be expected from an evaporative process. Chemical analysis indicated that there were no major changes in the mass proportion of 2 specific aromatic hydrocarbons (benzo[a]pyrene and benzo[k]fluoranthene) in the particles resulting from the aerosolization process.

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Related in: MedlinePlus

Particle number distributions of aerosols deposited in the electronic low pressure impactor with and without the spacer (mean, n = 5). Two apparent size modes, Number Mode 1 (NM1) and Number Mode 2 (NM2), are labeled.
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f4-ijn-3-435: Particle number distributions of aerosols deposited in the electronic low pressure impactor with and without the spacer (mean, n = 5). Two apparent size modes, Number Mode 1 (NM1) and Number Mode 2 (NM2), are labeled.

Mentions: The number deposition on each stage was normalized for the width of the particle size range (in logarithms) collected on each stage, creating histograms similar to particle size distributions (Figure 4). The number distributions of the suspension formulation were similar and appear to be multimodal with primary maxima <100 nm (Number Mode 1, NM1) and secondary maxima at approximately 300 nm (Number Mode 2, NM2). These distributions are discussed in conjunction with the mass distributions below.


The generation of diesel exhaust particle aerosols from a bulk source in an aerodynamic size range similar to atmospheric particles.

Cooney DJ, Hickey AJ - Int J Nanomedicine (2008)

Particle number distributions of aerosols deposited in the electronic low pressure impactor with and without the spacer (mean, n = 5). Two apparent size modes, Number Mode 1 (NM1) and Number Mode 2 (NM2), are labeled.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2636590&req=5

f4-ijn-3-435: Particle number distributions of aerosols deposited in the electronic low pressure impactor with and without the spacer (mean, n = 5). Two apparent size modes, Number Mode 1 (NM1) and Number Mode 2 (NM2), are labeled.
Mentions: The number deposition on each stage was normalized for the width of the particle size range (in logarithms) collected on each stage, creating histograms similar to particle size distributions (Figure 4). The number distributions of the suspension formulation were similar and appear to be multimodal with primary maxima <100 nm (Number Mode 1, NM1) and secondary maxima at approximately 300 nm (Number Mode 2, NM2). These distributions are discussed in conjunction with the mass distributions below.

Bottom Line: Inertial impaction data indicated that the particle size distributions of the generated aerosols were trimodal, with count median aerodynamic diameters less than 100 nm.Scanning electron microscopy of deposited particles showed tightly aggregated particles, as would be expected from an evaporative process.Chemical analysis indicated that there were no major changes in the mass proportion of 2 specific aromatic hydrocarbons (benzo[a]pyrene and benzo[k]fluoranthene) in the particles resulting from the aerosolization process.

View Article: PubMed Central - PubMed

Affiliation: Department of Biomedical Engineering, University of North Carolina, Chapel Hill, NC, USA. cooneyinsf@gmail.com

ABSTRACT
The influence of diesel exhaust particles (DEP) on the lungs and heart is currently a topic of great interest in inhalation toxicology. Epidemiological data and animal studies have implicated airborne particulate matter and DEP in increased morbidity and mortality due to a number of cardiopulmonary diseases including asthma, chronic obstructive pulmonary disorder, and lung cancer. The pathogeneses of these diseases are being studied using animal models and cell culture techniques. Real-time exposures to freshly combusted diesel fuel are complex and require significant infrastructure including engine operations, dilution air, and monitoring and control of gases. A method of generating DEP aerosols from a bulk source in an aerodynamic size range similar to atmospheric DEP would be a desirable and useful alternative. Metered dose inhaler technology was adopted to generate aerosols from suspensions of DEP in the propellant hydrofluoroalkane 134a. Inertial impaction data indicated that the particle size distributions of the generated aerosols were trimodal, with count median aerodynamic diameters less than 100 nm. Scanning electron microscopy of deposited particles showed tightly aggregated particles, as would be expected from an evaporative process. Chemical analysis indicated that there were no major changes in the mass proportion of 2 specific aromatic hydrocarbons (benzo[a]pyrene and benzo[k]fluoranthene) in the particles resulting from the aerosolization process.

Show MeSH
Related in: MedlinePlus