- Aflatoxins are mycotoxins. - They are produced by specific species of the fungus Aspergillus. - Aspergillus flavus and Aspergillus parasiticus are the most common producers of aflatoxins. - Aflatoxins are potent carcinogens and can cause liver damage. Sleeping sickness is caused by parasites of the genus Trypanosoma and is transmitted by the tsetse fly.