HR: 0800h
AN: A51E-0119    [Abstracts]
TI: Outflow of Anthropogenic Semivolatile Organic Compounds From Asia and Trans-Pacific Transport to the Pacific Northwest of the U.S.A. in Spring 2004
AU: * Primbs, T
EM: primbst@onid.orst.edu
AF: Dept. of Chemistry, Oregon State University, 1007 ALS Bldg., Corvallis, OR 97331 United States
AU: Wilson, G
EM: glenn.wilson@oregonstate.edu
AF: Dept. of Environmental and Molecular Toxicology, Oregon State University, 1007 ALS Bldg., Corvallis, OR 97331 United States
AU: Schmedding, D
EM: david.schmedding@oregonstate.edu
AF: Dept. of Environmental and Molecular Toxicology, Oregon State University, 1007 ALS Bldg., Corvallis, OR 97331 United States
AU: Higginbotham, C
EM: chigginbotham@cocc.edu
AF: Department of Science, Central Oregon Community College, 209 Ochoco 2600 N.W. College Way, Bend, OR 97701 United States
AU: Simonich, S
EM: staci.simonich@oregonstate.edu
AF: Dept. of Chemistry, Oregon State University, 1007 ALS Bldg., Corvallis, OR 97331 United States
AU: Simonich, S
EM: staci.simonich@oregonstate.edu
AF: Dept. of Environmental and Molecular Toxicology, Oregon State University, 1007 ALS Bldg., Corvallis, OR 97331 United States
AB: Air pollutants, including semivolatile organic compounds (SOCs), may undergo long-range atmospheric transport from Eurasian sources to the Pacific Coast of North America. SOCs can serve as molecular markers to indicate pollutant source type and geographical origin because they represent emissions from combustion (polycyclic aromatic hydrocarbons (PAHs)), agricultural (pesticides), and industrial (polychlorinated biphenyls (PCBs)) sources. Additionally, SOCs exist in the gas and/or particle phases and have a wide range of atmospheric lifetimes (hours-months). Atmospheric measurements of anthropogenic SOCs were made at a high elevation site in the Pacific Northwest of the U.S. and at a site close to Eurasian sources (Okinawa, Japan) to further understand the trans-Pacific transport of SOCs. High volume air sampling (~25 m³/hr for 24 hour periods) of both the gas and particulate phases was conducted on top of the summit building of Mt Bachelor, Oregon, U.S.A., located in Oregon's Cascade Mountain Range, beginning the 20^th of April 2004 and is ongoing. Additionally, high volume air sampling was conducted at Hedo Point, Okinawa, Japan during a six week campaign from the 19^th of March to the 1^st of May 2004. The gas phase was collected using a combination of polyurethane foam (PUF) and XAD-2 resin, while the particle phase was collected using quartz fiber filters. The samples were extracted using accelerated solvent extraction and the extracts analyzed by gas chromatography coupled with mass spectrometry (electron impact and electron capture negative ionization). Air trajectories were calculated using data from NOAA`s HYSPLIT model and imported into the ARC/GIS program for spatial representation. The presence of 80 anthropogenic SOCs was investigated. Initial results from the measurements in Okinawa showed elevated levels of particulate phase PAHs, hexachlorobenzene (HCB), and hexachlorcyclohexanes (HCHs) in samples corresponding to trajectories from the direction of China, compared to samples with trajectories associated with Japan. Preliminary results for Mt Bachelor showed elevated concentrations of PAHs, HCB, HCHs, and endosulfans in a sample collected on 25-26 April 2004 (trans-Pacific atmospheric transport event) as compared to a sample collected on 21-22 April 2004 (non-trans-Pacific atmospheric transport). Higher molecular weight PAHs were measured in the trans-Pacific event and not in the non-trans-Pacific event at Mt. Bachelor. The alpha to gamma HCH ratio has been used as an indicator of source region and it was very similar in most of the air masses sampled during the Okinawan air sampling campaign, with an average of 2.5 ± 1.0. The alpha to gamma HCH ratio in the trans-Pacific transport event at Mt Bachelor was 1.4 and 4.7 in the non-trans-Pacific event. In 2004, Shen et al. reported a N. American alpha to gamma ratio average of 3.6 and measurements closest to the Northwest of the U.S. in British Columbia had an average of 5.2. Additional samples from Mt Bachelor coupled with measurements from the Okinawan air sampling campaign will potentially further distinguish the differences in the trans-Pacific versus non-trans-Pacific atmospheric influences to Pacific Northwest.
DE: 0365 Troposphere: composition and chemistry
DE: 0368 Troposphere: constituent transport and chemistry
SC: Atmospheric Sciences [A]
MN: Fall Meeting 2005