Urinary fluoride levels in polytetrafluoroethylene fabricators.

Abstract

Urinary fluoride levels were investigated as an index of polytetrafluoroethylene (PTFE) exposure, since carbonyl fluoride, a pyrolysis product of PTFE, is metabolized and excreted as inorganic fluoride ion. Spot urine samples and occupational histories relating to polymer fume fever were obtained from 77 workers at a small PTFE fabricating plant. Environmental air sampling for PTFE was also performed. Air levels of PTFE ranging from 0 to 5.48 mg/m3 were found. All urine values fell below the level at which systemic effects are reported to occur. Analyses of the results by the method of analysis of variance demonstrated that the mean urinary fluoride level among workers who had one or more years of exposure to PFTE who also had experienced one or more reported episodes of polymer fume fever was significantly higher (P < 0.01) than that among employees with less than one year or more of exposure and no history of polymer fume fever. Additional exposure beyond one year and additional polymer fume fever episodes did not result in the further elevation of urine fluoride levels.