Urinary platinum levels of 21 nurses and hospital pharmacy personnel occupationally exposed to platinum containing antineoplastic drugs were determined in 24-h urine by voltammetric analysis after UV photolysis. All study participants applied standard safety measures, including a vertical laminar air-flow cabinet and latex gloves. The amount of platinum-containing drugs prepared for intravenous application ranged from 40-3260 mg/day. Urinary platinum was detected in 9 of 52 urine samples collected on days when platinum-containing drugs were mixed (limit of determination 4 ng/l). In comparison with a non-exposed control group, elevated urinary platinum levels were found in one pharmacist (35 ng/g creatinine) and one pharmacy technician (28 ng/g creatinine). The pharmacist's urinary platinum remained elevated after 2 days without occupational exposure to antineoplastic drugs. The urinary platinum level of the pharmacy technician dropped considerably after several weeks without handling cytostatic drugs. Voltammetric detection of urinary platinum is a highly sensitive method suitable for biological and environmental monitoring.