Thallium poisoning in group assassination attempt.

The use of thallium in an attempted assassination of four members of a political organization is described. The intended victims first complained of abdominal pain within two days of eating a snack prepared by their host; painful peripheral neuropathy occurred within one week and loss of hair within three weeks. Swelling of the optic disk was observed in one patient. The diagnosis was made on clinical grounds and confirmed by the detection of high levels of thallium in serum, urine, and hair and/or nail samples. All patients recovered completely. The possibility of thallium poisoning should be considered in patients who present with acute onset of gastrointestinal symptoms, pain and paresthesias in the legs, and hair loss, so that appropriate treatment can be initiated at an early stage.