The reported investigations on the uptake of carbon disulphide (C 5 2 ) and the excretion of its metabolite 2-thiothiazolidine-4-carboxylic acid (TTCA) were based on results from 403 personal air samples ( 352 passive and 51 active samples) and 362 TTCA determinations in biological material measured during a field study on the adverse effects due to C 5 2 exposure. The external exposure ranged from below the detection limit ( 0 2 ppm) to 66 ppm and the urinary TTCA excretion from below the detection limit ( 0 16 mg /l) to 33.4 mg/1 The excretion of TTCA in postshift urine related to creatinine and volume showed a linear correlation to the C 5 2 air concentration On the basis of these results the influence on the internal exposure of physical work load, dermal exposure and individual parameters (age, Brocaindex, disturbed skin barrier) was evaluated Correlations between the TTCA values in the postshift urine and the individually measured C 5 2 concentrations were carried out separately for individual departments and persons with and without indications of a disturbed skin barrier In order to be able to judge the individual internal exposure related to external exposure, a personal quotient was formed from the TTCA level in the urine and the C 5 2 air concentration measured on the same day (relative interal exposure RIE index = TTCA mg/g creatinine/C 52 in ppm) On investigating interindividual differences, higher relative internal exposures were found in persons with a heavy physical work load and more intensive skin contact It could be shown for a large group of persons exposed to C 5 2 that a pathological skin Dedicated to Professor G Zehnert on the occassion of his 65th birthday