Sweet-flag

The rootstocks of this aromatic plant are used as a natural insecticide and an ingredient of perfumes. They were used by Amerindians for various medicinal purposes, and reportedly induce hallucinations if eaten in sufficiently large quantities. These properties are primarily the result of Alpha-asarone and Beta-asarone; the latter has been found to be carcinogenic. As a consequence, the Food & Drug Administration (FDA) has banned the use of the rootstocks as a food additive.