Use of 18F labelled fluorocarbon-11 to investigate the fate of inhaled fluorocarbons in man and in the rat.

, , 99-103. The distribution and elimination of F labelled fluorocarbon-11 has been followed in a group of rats killed after air breathing following six minutes' exposure to F fluorocarbon-11. Whole body and individual organ count rates were measured. In four volunteers the fate of F labelled fluorocarbon-11 was followed by both whole body counting and gamma camera measurement of the activity in the lung and mouth region after inhalation from a specially loaded aerosol dispenser. In the rat there was a high initial level in high blood flow organs and in the adrenals and fat: the level in blood and high blood flow organs fell rapidly. Elimination from fat was slow but the adrenal level had fallen within one hour. The fall in whole body count rate was similar to that in fat. In man, the fall in lung concentration was consistent with rapid uptake into tissues followed by slow elimination; the whole body count rate curve also indicated slow elimination. There was no evidence of deposition of droplets of fluorocarbon in the mouth region after use of the aerosol.