SPLAT: Real-Time Characterization of Individual Exhaust Particles (Zelenyuk's EE proposal: PNNL scope #48932)
EMSL Project ID
17803
Abstract
The research community has reached consensus on the adverse health effects of fine particles smaller than 2.5 μm (PM2.5). Numerous epidemiological studies suggest a correlation between air pollution, particularly Particulate Matter (PM) loading and health effects. They do not, however, provide sufficient details to identify the specific components and properties of the PM that are responsible. It is reasonable to assume that the impact of PM on human health would be a function of not only the PM loading, but its chemical and physical characteristics, which in turn are a function of what and how much is emitted and the transformations particles undergo in the atmosphere. In other words, the real-world health effects of PM are a function of the particle history from emission to inhalation. As one would expect health effects of a microgram of ammonium sulfate particles and a microgram of Poly Aromatic Hydrocarbons (PAH) or a microgram of transition metals containing particles will be very different. Yet the epidemiological studies and air quality standards treat all particles the same way, which results in marginal and difficult to establish correlations.
Only a fundamental scientific understanding of the mechanism by which atmospheric particles, in particular energy related particulate emissions, affect our health will make it possible to develop smart regulations that maximize public protection and minimize economic impact. The same fundamental knowledge will serve the health community in developing better drug delivery tools and help develop work safety procedures in places where micron and nano-sized particles are generated.
Our objective here is to establish the link between energy related particulate emissions, specifically emissions from mobile sources as a major source of fine particles in the environment, and their health effects.
Our research plan is based on a novel comprehensive approach to characterize chemical, physical and biological properties of fine PM in order to gain an understanding of the physiological effects of fine particles.
We have recently developed Single Particle Laser Ablation Time-of-flight Mass Spectrometer (SPLAT) perfectly suitable for the real-time characterization of size, composition and density of individual exhaust particles. The instrument was specifically designed to provide high sensitivity for particles in the 150nm to 50nm range to cover the bulk of the particle mass that is present in the exhaust.
When SPLAT is combined with DMA in addition to particle aerodynamic size and composition it is possible to measure in real-time the density of individual particles and derive the fractal dimension of diesel soot.
Project Details
Project type
Exploratory Research
Start Date
2006-01-23
End Date
2007-01-05
Status
Closed
Released Data Link
Team
Principal Investigator
Related Publications
Yang, J., Stewart, M., Maupin, G., Herling, D. and Zelenyuk, A. (2008). Single Wall Diesel Particulate Filter (DPF) Filtration Efficiency Studies Using Laboratory Generated Particles Chemical Engineering Science, doi:10.1016/j.ces.2008.12.011
Zelenyuk A, J Yang, EY Choi, and DG Imre. 2009. "SPLAT II: An Aircraft Compatible, Ultra-Sensitive, High Precision Instrument for In-Situ Characterization of the Size and Composition of Fine and Ultrafine Particles." Aerosol Science and Technology 43(5):411-424.