Eugenol is a flavour component, which is present in cloves and some other spices. Cloves contain up to 15% of eugenol. It also has the characteristic smell of cloves.
Eugenol is also added to cosmetics, pharmaceutical products and toothpaste as flavour.
structure of eugenol
Eugenol is insoluble in water, but readily soluble in alcohol or oils.
A side effect of eugenol is that it works as an analgesic (painkiller). Cloves thus were used for a long time as painkillers with toothache. A clove on a aching tooth will reduce the pain considerably.
Eugenol is not very toxic, the acute toxic dose is several grams/kg bodyweight, which is the equivalent of nearly 100 gram of cloves in a single dose.