Historically veterinarians have diagnosed accidental poisonings and identified possible terrorist events before they have come to the attention of public health authorities. There are many toxins that pose a threat to both humans and animals and the authors examine several of them here, namely, anthrax, tricothecenes, staphylococcal enterotoxin B, botulinum toxins, ricin, saxitoxin and dinoflagellate toxins. By discussing exposure routes, clinical signs and differential diagnoses the authors demonstrate how veterinarians are in a unique position to recognise zoonotic diseases, toxin exposure, and acts of bioterrorism. The work of veterinarians protects the food supply and contributes to human health and this article highlights the importance of coordination and communication between veterinarians and physicians. Sharing information is critical in confirming diagnoses and, in the case of intentional toxin attacks, could also be beneficial in identifying the perpetrators of the crime.