W5 AM Perfluorochemical Monitoring
Wednesday, 16 November 2005: 8:00 AM - 11:40 AM in 321-323
(BAR-1117-828329) A study of fluorinated alkyl compounds in European air samples.
Barber, J1, Berger, U2, Jones, K1, 1 Lancaster University, Lancaster, UK2 Norwegian Institute for Air Research (NILU), Tromso, Norway
ABSTRACT- In recent years, perfluorooctane sulfonate (PFOS) and perfluorinated carboxylic acids (PFCAs) have been detected in a large variety of environmental samples from places as remote as the Arctic. These compounds are ionic and possess very low volatility, and therefore not expected to undergo long-range atmospheric transport (LRAT). It has been proposed that instead, neutral volatile precursor compounds, such as fluorotelomer alcohols (FTOHs) and fluorooctane sulfonamides/sulfonamide ethanols (FOSAs/FOSEs), might undergo LRAT and ultimately be degraded to PFCAs and PFOS at these remote locations. The aim of this study was to provide first evidence for the presence of volatile fluorinated compounds in European air samples. The study used high-volume samplers to collect gas-phase and particle-bound fluorinated compounds on polyurethane foam (PUF)/XAD-2 resin/PUF sandwiches and glass fiber filters (GFFs), respectively. Field blanks and samples of 
1400 m3 air were collected at Manchester (UK, urban site) and Hazelrigg (40 miles north-west of Manchester, semi-rural site) in February and March 2005. Neutral compounds were extracted from the PUFs/XAD or filter with ethyl acetate and analyzed by GC/NCI- and GC/PCI-MS. Additionally, GFF samples were analyzed for PFCAs and perfluorinated sulfonates. These ionic compounds were extracted from the filter with methanol and analyzed by LC/TOF-MS. All 9 volatile target compounds were detected in the gas-phase at both locations, and in the particulate-phase in the Manchester samples, with concentrations higher in urban samples than rural samples. The volatile compounds with the highest concentrations were 8:2 FTOH, followed by 6:2 FTOH, both found in the hundreds of pg/m3 range, with N-methyl-FOSE the most abundant of the FOSAs/FOSEs. Interestingly, a number of ionic compounds were present in the particulate-phase, including PFOA, PFOS, PFHpA, PFDcA, and TH-PFOS, with PFOS at 50 pg/m3, and PFOA at levels >800 pg/m3, surprisingly making PFOA the most abundant fluorinated analyte in these air samples.
Key words: Air, PFOS, PFOA, FTOHs