Pharmacokinetics of ethylene in man by on-line laser photoacoustic detection

The pharmacokinetics of ethylene are determined using laser-based photoacoustic detection and a closed chamber setup. Concentration-time data are analyzed using a two-compartment and a physiologically based pharmacokinetic (PBPK) model. Endogenous production was 92 +/- 13 pmol/h/kg for the two-compartment model and 75 +/- 10 pmol/h/kg for the PBPK model. These values agree with previous work at our department but are significantly lower than published values based on gas chromatography. The blood:air partition coefficient in the PBPK model was determined by curve fitting, because simulations based on published values did not agree well with data. Curve fitting gave a value of 0.092 +/- 0.029. The real-time nature and high sensitivity of photoacoustic detection make it a useful addition to gas chromatography in closed chamber studies.