Urinary excretion of ethoxyacetic acid after experimental human exposure to ethylene glycol monoethyl ether

Ten healthy male subjects were exposed to ethylene glycol monoethyl ether (EGEE) under various conditions of exposure concentration and physical workload and their urinary excretion of ethoxyacetic acid was followed up for 42 hours. Maximal excretion of ethoxyacetic acid was reached three to four hours after the end of the four hour exposure period. Afterwards, ethoxyacetic acid excretion declined slowly with a biological half life of 21-24 hours. Ethoxyacetic acid excretion increased as the uptake of EGEE increased as a consequence of higher exposure concentration or pulmonary ventilation rate during physical exercise. On average, 23.1 +/- 6.3% of EGEE was recovered as ethoxyacetic acid within 42 hours and the recovery did not change as the uptake of EGEE increased. Quantitative relations between ethoxyacetic acid excretion and EGEE uptake were obtained and the relevance of ethoxyacetic acid excretion as a measure for exposure to EGEE is discussed.