[Chronic thallium poisoning. Study of criminal poisoning].

In a 42-year-old man with abdominal symptoms, loss of hair and increasing distal polyneuropathy in both legs, the clinical suspicion of thallium poisoning was confirmed by urinary and blood analysis. Hair analysis provided a pointer to the time of poisoning. In addition to symptomatic measures, treatment consisted of administration of potassium-iron (III) hexacyanoferrate (II) (Berlin blue), combined with forced diuresis. Despite the overall favourable course, residual symptoms of distal polyneuropathy were still present 6 months after discharge from hospital.