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1H a - Perfluorinated Substances (WE6/2) Indoor/outdoor air measurements and partitioning of perfluorinated compounds. Shoeib, Mahiba1, Harner, Tom1, Kannan, Kurunthachalam2, 1 Environment Canada - MSC, Toronto, Ontario, Canada2 Wadsworth Center, New York State Dept. of Health, Albany, New York, USA ABSTRACT- Perfluoro-octane sulfonate (PFOS) is a globally distributed contaminant that has been detected in wildlife in remote locations where it has never been used. These findings suggested that PFOS or its precursors are capable of long range transport atmospheric (LRAT). In order to better understand the partitioning and fate of these chemicals we undertook to measure the octanol/air partition coefficient (Koa) over the range 0 to +20 C. Octanol has been successfully used to describe the partitioning of hydrophobic, non-polar chemicals to environmental phases such as soil, vegetation and aerosols. Values of log Koa (at 20 C) ranged from approximately 5 for the fluorotelomers to 7.5 to 8 for the fluorosulfonamides. Based on empirical relationships derived for non-polar, hydrophobic chemicals, the fluorosulfonamides should exist mainly in the gas-phase. However, results from indoor air samples (collected using conventional high volume samplers) show that they are mainly associated with particulate matter, indicating that revised partitioning relationships are necessary for these compounds. Indoor air concentrations were in the range 10-10000 pg/m3 and were approximately 400 times greater than outdoor values. A second, more extensive survey of fluorosulfonamides compared indoor (n=80 homes) versus outdoor (n=10) levels using passive air samplers. Key words: fluorosulfonamides, fluorotelomers, Koa (octanol/air partition coefficient), indoor air |
