Biological agents can be introduced into food either inadvertently -- through poor food handling or food-processing techniques -- or deliberately. Deliberate food contamination with a biological agent can be identified during an investigation of an outbreak of a foodborne illness or by a warning or threat of contamination. It is often difficult to associate an outbreak of foodborne illness with a specific incident of contamination. Food contamination can result in illnesses that range from temporary maladies, which may not require medical treatment; to acute and chronic illnesses, such as kidney failure in infants; to death. To date, deliberate contamination of food with a biological agent has rarely occurred, with two acts identified in 1984 that produced short-term illnesses but no deaths. The Food and Drug Administration (FDA) has written procedures for contacting key FDA and other Federal officials and experts to quickly develop an approach to respond to threats or acts of contamination. The approach may involve assessing the credibility of a threat or requesting a recall of the contaminated food. The Food Safety and Inspection Service (FSIS) also has written procedures for responding to acts of contamination, which include conducting a preliminary investigation to assess the health hazards and, if necessary, requesting a recall. For threats of contamination, FSIS is developing a plan that will include coordination steps with other affected Federal agencies. It is recommended that the effectiveness of Federal food safety procedures be tested using a variety of scenarios involving food deliberately contaminated with biological agents and including various players, such as State and local agencies. 6 footnotes