Quantitative determination of fluorochemicals in municipal landfill leachates

Twenty-four fluorochemicals were quantified in landfill leachates recovered from municipal refuse using an analytical method based on solid-phase extraction, dispersive-carbon sorbent cleanup, and liquid chromatography/tandem mass spectrometry. The method was applied to six landfill leachates from four locations in the US as well as to a leachate generated by a laboratory bioreactor containing residential refuse. All seven leachates had the common characteristic that short-chain (C-4-C-7) carboxylates or sulfonates were greater in abundance than their respective longer-chain homologs (>= C8). Perfluoroalkyl carboxylates were the most abundant (67 +/- 4% on a nanomolar (nM) basis) fluorochemicals measured in leachates: concentrations of individual carboxylates reaching levels up to 2800 ng L-1. Perfluoroalkyl sulfonates were the next most abundant class (22 +/- 2%) on a nM basis: their abundances in each of the seven leachates derived from municipal refuse were greater for the shorter-chain homologs (C-4 and C-6) compared to longer-chain homologs (C-8 and C-10). Perfluorobutane sulfonate concentrations were as high as 2300 ng L-1. Sulfonamide derivatives composed 8 +/- 2.1% (nM basis) of the fluorochemicals in landfill leachates with methyl (C-4 and C-8) and ethyl (C-8) sulfonamide acetic acids being the most abundant. Fluorotelomer sulfonates (6:2 and 8:2) composed 2.4 +/- 1.3% (nM basis) of the fluorochemicals detected and were present in all leachates. (C) 2010 Elsevier Ltd. All rights reserved.