Toxins are non-living biological agents produced by living plants, animals, or bacteria. an example of a toxin is:

Botulinum toxin

Toxins are non-living biological and chemical agents produced by living microorganisms from animals and plants that can cause harm to humans, plants and animals. An example of toxin is botulinum toxin produced by the bacterium Clostridium, which is a neurotoxic protein that prevents the release of the neurotransmitter acetylcholine from axon endings at the neuromuscular junction and causes flaccid paralysis.

Moreover, toxin are more closely related to chemical warfare agents that can only affect those who are exposed to the agent and that they are not considered as transmissible disease.