Plasma fluoride and bromide concentrations during occupational exposure to enflurane or halothane

The plasma fluoride and bromide concentrations were studied in operating theatre personnel. When enflurane was used, the increase in plasma fluoride concentration could not be distinguished from normal individual variations, but the plasma bromide concentration increased significantly when halothane was used. Seven patients were exposed to enflurane in a concentration of 200 parts per million for 4 h. A significant increase in the plasma concentration of fluoride was observed. The peak concentrations of fluoride occurred during exposure and the increase lasted less than 12 h. The increase in fluoride concentration was larger at this trace concentration than reported after anaesthetic concentrations. Cerebrospinal fluid (CSF) fluoride concentration was also studied; a smaller and delayed increase was found in CSF compared to plasma.