Organofluorine compounds in the environment: Analysis, sources and fate

An evaluation of 19F nmr as an analytical for the measurement of trifluoroacetic acid (TFA) and other fluorinated acids in the aquatic environment was conducted. A method based upon strong anionic exchange (SAX) chromatography was also optimized for the concentration of the fluoro acids prior to nmr analysis. Extraction of the analyte from the SAX column was carried out directly in the nmr solvent in the presence of the strong organic base, DBU. The method allowed the analysis of the acid without any prior clean up steps being involved. Optimal nmr sensitivity based upon T1 relaxation times was investigated for seven fluorinated compounds in four different nmr solvents. The use of the relaxation agent chromium acetylacetonate, Cr(acac)₃, within these solvent systems was also evaluated.; The lampricide 3-trifluoromethyl-4-nitrophenol (TFM) is added annually to the Great Lakes. TFM was shown to undergo photohydrolytic degradation, at 365 nm and under actinic radiation, to produce TFA. The TFA was analyzed using the 19F nmr developed. A mechanistic study for the production of TFA from TFM was conducted and the structural parameters associated with the production of TFA from trifluoromethylated phenols were investigated. It was found that the yield of TFA is clearly dependent on the nature of the trifluoromethylated phenol. The nature of the substituents, the substitution pattern, and the pH strongly affected the photolytic half life of the parent compound and the yield of TFA.; The environmental fate of trichloro, dichloro, and monochloroacetic acids, and TFA was investigated using-field aquatic microcosms and laboratory sediment-water systems. Trifluoroacetic acid was extremely persistent and showed no degradation during a one year field study, though it appeared to undergo transient partitioning within an unknown pond phase as the temperature of the surroundings was reduced.; Thermal degradation is expected to be a primary mode of destruction for highly stable fluoropolymers. The thermolysis of Teflon® and Kel-F® resulted in the production of trifluoroacetate and chlorodifluoroacetate (7.7 and 9.5% w/w respectfully) which is proposed to contribute to the atmospheric burden of both haloacetic acids. (Abstract shortened by UMI.)...