A case report of an unresponsive chemist presenting to the emergency department is presented; in retrospect, the patient was discovered to have intentionally ingested cyanide. A literature review regarding ingestions in laboratory & health care personnel revealed 5 common points: barbiturates, carbon monoxide, cyanide, azides & methemoglobin-inducing chemicals. Key diagnostic findings, in the absence of history of exposure, are discussed for these 5 agents. (59 refs.)