PT05 Atmospheric Transport and Fate
Exhibit Hall
8:00 AM - Tuesday
(PT070) Gas particle partitioning of Chlordanes in coupled indoor / outdoor air samples from three US cities.
Offenberg, John1, Naumova, Yelena2, Polidori, Andrea 2, Turpin, Barbara2, Eisenreich, Steven 2, 3, Morandi, Maria4, Colome, Steven5, Weisel, Clifford 6, 1 US EPA2 Rutgers University Department of Environmental Sciences3 Institute for Environment and Sustainability, European Commission, Joint Research Centre4 , School of Public Health, University of Texas, Houston Health Science Center5 Integrated Environmental Sciences6 Environmental and Occupational Health Sciences Institute
ABSTRACT- Concentrations of six Chlordane species (trans-chlordane, cis-chlordane, trans-nonachlor, cis-nonachlor, oxychlordane and MC5) were measured indoors and outdoors at 157 non-smoking residences in three urban areas during June 1999-May 2000. These measurements were performed on a subset of samples collected within the Relationship of Indoor, Outdoor, and Personal Air study (RIOPA). The objective of the study was to evaluate the hypothesis that outdoor air pollution strongly contributes to indoor air pollution. Forty-eight hour integrated samples were collected from homes in Los Angeles County, CA, Houston, TX, and Elizabeth, NJ. Both particle bound (PM2.5; quartz fiber filter) and vapor phase (PUF adsorbant) chlordane concentrations were separately measured by GC / EI-MS after solvent extraction. The measured partition coefficients of Chlordanes were correlated with the compounds′ sub-cooled liquid vapor pressures. Measured partition coefficients varied by two orders of magnitude for any value of vapor pressure. These variations in gas/particle partitioning of Chlordanes are related to the aerosol characteristics and sampling conditions. Multiple linear regression analysis (MLR), which included temperature corrected vapor pressure, fOC and fEC as independent variables, as well as corresponding interaction terms, explains up to 44 % of the variability of the partition coefficients. This is higher than the explained variance when vapor pressure is used as a single parameter. The relative importance of each variable for prediction of partition coefficients in both indoor and outdoor air will be discussed. Further comparisons of octanol-air partition coefficient with vapor pressure will also be presented. Although this work was reviewed by EPA and approved for publication, it may not necessarily reflect Agency policy.
Key words: pesticide, RIOPA, indoor air