PM06 Emerging Pollutants
Exhibit Hall
8:00 AM - Monday
(PM059) Saturated and unsaturated telomer acids in rainfall from Winnipeg, Manitoba (Canada).
Loewen, M1, Halldorson, T1, Tomy, G1, 1 Department of Fisheries and Oceans, Winnipeg, Manitoba, Canada
ABSTRACT- Perfluoroalkylethanols are straight chain FOCs having the general formula CnF2n+1CH2CH2OH (n = 2, 6, 8...14). Also referred to as fluorotelomer alcohols (FTOHs), these compounds are used as surfactants and also as intermediates in processing of other products which themselves have many uses, including polymers, adhesives and paints. The worldwide production of FTOHs for the period of 2000-2002 was estimated to be between 5-6.5 x 106 kg yr-1, of which 40% is produced in North America. Although the processes that lead to the release of FTOHs into the environment is still unclear, recent measurements in the troposphere imply that FTOHs are escaping from their intended products. Atmospheric lifetimes of some of the shorter chain length FTOHs, also suggests that transport to remote regions is highly likely. Although deposition of FTOHs by wet and dry deposition are unlikely due to the relatively high vapour pressure and low water solubility of these compounds, it is clear that they are being cleansed from the atmosphere. One plausible mechanism for degradation of FTOHs in the atmospheric environment is oxidation. Atmospheric oxidation of FTOH during a rain event to telomer acids [saturated: 2H, 2H-perfluoroalkanoic acids and unsaturated: 2H-perfluoro-2-alkenoic acid] would dramatically increase the trend toward wet deposition by decreasing the vapour pressure and increasing the water solubility. We report here low pg/L concentrations of telomer acids (C10 and C12 saturated and unsaturated) in rainwater collected in Winnipeg MB. These studies suggest that at least some deposition of fluoro and perfluorocarboxylic acids in the environment is attributable to perfluorooctylethanol and other FTOHs, respectively.
Key words: Telomer alcohols, Telomer acids, fluorinated organic compounds