Seven healthy volunteers were exposed to approximately 100 ppm (=520 mg/m3) trichloroethylene for six hours daily during a period of five consecutive days. A corresponding group was exposed a placebo in the same manner. -Biochemical and psychological examinations were accomplished in the beginning and the end of each day respectively the whole period. Thereby the intraindividual as well as the interindividual loads were taken to judge the health impairment. - For this purpose trichloroethylene, trichloroethanol and trichloracetic acid were determined in blood, as well as total trichloroethanol and trichloroacetic acid in urine. For the measurement of the biochemical parameters gaschromatography is considered the best method. The combination of the "intern standard" with the synchronous determination of the metabolites of trichloroethylene is described as a new treatment. These time-efficient and practicable procedures are the most important suppositions for "biological monitoring". Results are confirmed as far as known in literature as well as the course of trichloroethylene in blood is described for the first time. The modern methods of psychology applied to tests and standardized questionaires served to quantify the intellectual and psychological conditions of the solvent exposed volunteers and of their corresponding group. The group results were compared. Thereby no significative differences were visible. Altogother the results show that during the 5 days exposition to 100 ppm (=520 mg/m3) trichloroethylene no impairments of the examined persons' mental and psychological capacities could be determined in spite of the biochemically quantified incorporation of the solvent.