Kinetics of tetrachloroethylene in volunteers; influence of exposure concentration and work load

Summary Six male volunteers were exposed for 4 h to 72 ppm tetrachloroethylene (PERC) at rest, to 144 ppm PERC at rest, and to 142 ppm PERC at rest combined with work load (2 times 30 min, 100 W). Minute volume and concentrations in exhaled air were measured to estimate the uptake. Concentrations of PERC and trichloroacetic acid (TCA) were determined in blood. Exhaled air was analysed for PERC; urine for TCA.The uptake/min decreased in the course of the exposure to 60 % of the initial uptake. The total uptake was influenced more by (lean) body mass than by respiratory minute volume or adipose tissue. During work load the uptake and minute volume increased to 3 fold the value at rest. In the post exposure period the quotient of the bloodconcentrations and exhaled air concentrations of PERC remained nearly constant at 23. Following exposure about 80–100 % of the uptake was excreted unchanged by the lungs, whereas till 70 h after exposure the amount of TCA excreted in urine represented about 1 % of the uptake.