| MadSci Network: Botany |
I have pruned cherry laurel (Prunus laurocerasus) and never noticed any odor of cyanide. Cherry laurel would usually be toxic only if a person or pet ate parts of the plant. The plant contains a cyanogenetic glycoside, prulaurasin, that can be broken down by enzymes to release cyanide. When cherry laurel cells are damaged, enzymes are released. The first reference indicates that cherry laurel leaves have little odor unless crushed. The crushed leaves, especially young leaves, smell like benzaldehyde. The Roman emperor Nero supposedly poisoned people using cherry laurel water. Cherry laurel water is still recommended as an herbal medicine but can be fatal if ingested in a large enough dose. Possibly if you put a large amount of cherry laurel leaves and branches through a plant shredder and placed them in a closed car, you might be able to get cyanide poisoning. I doubt most people shred plants before they haul them to the dump so that seems unlikely. Cyanide poisoning by cherry laurel in a car might be a good test for the TV series Mythbusters. Cyanogenetic glycosides are secondary plant compounds that act to defend the plant against herbivores. References Cyanogenetic glycosides The Secondary Metabolism of Plants: Secondary Defence Compounds Cyanide Poisoning Cherry laurel in "A Modern Herbal"
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