Sources, symptoms, and signs of arsenic poisoning.

Arsenic poisoning continues to be a serious medical problem that may easily be overlooked or misdiagnosed. The broad constellation of symptoms and signs in arsenic poisoning, along with changing sources of this toxin, contributes to misdiagnosis. A re-examination of current potential sources was carried out. Sources were determined in 17 of 20 documented cases of arsenic poisoning. Fourteen cases resulted from ingestion of a single, commonly available, arsenic-containing ant killer. In contrast to earlier reports, this survey found that agricultural and industrial sources were relatively uncommon. A peculiar posturing of the hand is commonly seen in the early stages of arsenic poisoning prior to the development of Mee's lines or palmar hyperkeratosis. An illustrative case is reported that resulted from intermittent self-administration of an arsenic-containing ant killer in order to maintain a state of chronic invalidism.