title: Airborne Particulate Matter Size Distributions in an Arid Urban Area.
abstract: While there is a growing body of data on the health effects of particulate matter, there is little information available from areas that experience frequent dust storms, such as Spokane, WA. As part of a three-year study to investigate the health effects associated with exposure to atmospheric aerosols, ambient particulate matter in Spokane is being characterized according to particle size and chemical composition. In this report, particulate matter concentrations measured using continuous tapered-element oscillating microbalances for three size ranges are discussed. Particles with aerodynamic diameters less than 10 micrometers (PM10), less than 2.5 micrometers (PM25), and less than 1.0 micrometer (PM1.0) were measured at a residential site; PM10and PM2.5were measured at an industrial site. Based upon 1.5 years of data, PM10was found, on average, to consist of approximately 40% PM2.5at the industrial site and approximately 50% at the residential site, with higher fractions (up to 50% at the industrial site and up to 80% at the residential site) observed in the late fall or early winter (October-November). At the residential site, PM25was comprised of approximately 80% particles 1.0 micrometer and smaller. Only one windblown dust storm occurred during the sampling period, on July 24, 1994, during which both PM10and PM2.5concentrations were enhanced.
authors.affiliation: a Washington State University , Pullman , Washington , USA.
authors.forename: L
authors.initials: L
authors.lastname: Haller
authors.affiliation: a Washington State University , Pullman , Washington , USA.
authors.forename: C
authors.initials: C
authors.lastname: Claiborn
authors.affiliation: b University of Washington , Seattle , Washington , USA.
authors.forename: T
authors.initials: T
authors.lastname: Larson
authors.affiliation: b University of Washington , Seattle , Washington , USA.
authors.forename: J
authors.initials: J
authors.lastname: Koenig
authors.affiliation: b University of Washington , Seattle , Washington , USA.
authors.forename: G
authors.initials: G
authors.lastname: Norris
authors.affiliation: c Spokane County Air Pollution Control Authority , Spokane , Washington , USA.
authors.forename: R
authors.initials: R
authors.lastname: Edgar