Honey containing tutin can be produced by honey bees feeding on honeydew produced by sap-sucking vine hopper insects ("Scolypopa australis") feeding on tutu. The toxin is in the sap of the Tutu bush. This sap is eaten by the hoppers, but not all is digested. The undigested sap which contains a lot of plant sugars as well as tutin is excreted as honeydew onto the leaves of the bush. Bees then gather the honeydew and toxic honey is the result.