Submitted to: Society of Environmental Toxicology and Chemistry (SETAC)
Publication Type: Abstract Only
Publication Acceptance Date: 10/12/1998
Publication Date: N/A
Technical Abstract: The efficiency of an atmospheric dust collector to measure depositional fluxes of organic contaminants was evaluated using a co-located nine stage micro-orifice particle impactor and highly-resolved meteorological data. Size-distributions of atmospheric particles bearing various PAHs in a suburban airshed and detailed meteorological data are used to model dry depostion velocities and fluxes of particle-associated PAHs as a function of particle size. These data are compared to daily deposition measurements obtained using an atmospheric dust collector described as a semi-passive, open-air sampler. A key aspect of this work is the use of detailed meteorological data to incorporate episodic deposition-inducing conditions that affect local particle depositional fulxes of trace constituents over very short time scales. An apparent limit of the comparison is the micro-orifice's particle-size cut-off for large particles (ca.19 um). Observed differences in dry deposition between that estimated from the micro-orifice particle impactor data and that measured with the dust collector are attributed to the collection of large particles and gases by the dust collector.