Analysis of fluorotelomer alcohols, fluorotelomer acids, and short- and long-chain perfluorinated acids in water and biota

Fluorotelomer alcohols and fluorotelomer acids have been proposed as a source of the perfluorinated carboxylic acids found in remote marine locations. To examine the sources and fate of perfluorinated acids in the environment, a method to determine a wide range of poly- and perfluorinated acids in environmental and biological matrices is needed. In this study, a method has been developed to measure a suite of neutral and acidic fluorochemicals including, fluorotelomer alcohols, fluorotelomer acids, and short- and long-chain perfluorinated acids, in water and biological samples. The method involves solid-phase extraction with weak anion exchange (WAX) cartridges, followed by sequential elution with sodium acetate buffer, methanol, and 0.1% NH4OH in methanol. For biological samples, prior to solid-phase extraction, tissues are digested in 0.5N potassium hydroxide/methanol, diluted in water, and passed through the WAX cartridge. Neutral compounds and telomer alcohols are separated from other poly- and perfluorinated acids. The method is robust (i.e., capable of measuring neutral and acidic compounds), and can be applied for the analysis of a range of poly- and perfluorinated acids, including telomer alcohols, telomer acids, perfluoroalkylcarboxylates, and perfluoroalkylsulfonates in water and biota. With the use of high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS), a method detection limit in the range of several tens to hundreds of parts-per-quadrillion (pg/L) in water and at a few tens to hundreds of parts-per-trillion (pg/g) levels in biological matrices can be achieved.