Many Prunus species, and allies contain sufficient cyanogenic glycosides to pose a risk of cyanide poisoning if actually consumed, in the case of peace pits, they have even been used as a historic means of capital punishment, although I forget in what country. That bitter almond scent is pleasant though, I love marzipan, and working in the lab if ever I need to use benzaldehyde for anything (same smell, although without the toxicity of xyzC=-N (meant to look like a triple bond, there being nothing to represent it on the keyboard, and buggered if I can be bothered looking up to see if there is in ASCII) its always pleasant, first encountered it whilst making some TNT as a kid, having tried to run the nitration with a nitrate salt and conc. H2SO4, the entire room ponged to high heaven of marzipan, I could even smell it from the landing or down the stairs for a while it was that all-pervading. Much nicer than some things capable of doing the same though, far rather benzaldehyde than for instance, methanethiol (sort of fecal, rotting meaty, gas-leak like stink that CARRIES like nobodys fucking business, even a fungus species endemic to the british isles amongst other places, that releases trace quantities of it can sometimes be located by nose alone from as far as half a mile or so)