Thallium poisoning: an outbreak in Florida, 1988.

In October 1988, five of seven members of a Florida family were poisoned with thallium, constituting the largest outbreak of acute thallium poisoning in the United States since thallium was banned as a rodenticide in 1972. Three patients had an acute severe neuropathy with respiratory depression; one died. The other two had no symptoms. No cases were identified among nonhousehold relatives or friends, or in the community. Of the more than 100 environmental specimens collected at the family household and tested by atomic spectroscopy, three empty and four unopened glass soft drink bottles of the same lot number yielded thallium in a concentration fatal to humans. All family members who consumed the soft drink were poisoned (5/5) as compared with none of those who did not (0/2). Because poisoning was clustered to the family and police investigators provided evidence that the poisoning was deliberately targeted to the family, it was assumed that no other soft drink bottles contained thallium, and it was decided not to recall all soft drink bottles with the same lot number. A year later a neighbor of the family was arrested and convicted of the murder.