A material found quite widely in nature, especially in plants like comfrey. This material is also known as glyoxydiureide or 5-ureidohydantoin and its history is very interesting. During World War I it was observed that the wounds of soldiers in trenches appeared to heal more quickly than those kept under sanitary conditions. It was found that the trenches were infested with maggots which infested the wounds of many of the combatants and that the maggots secreted a material that improved healing. This material was found to be allantoin.It also occurs in tobacco seeds, sugar beet, wheat sprouts and comfrey (0,8%) as well as in rice polishings and in the bark of horse chestnut. Allantoin is a topical vulnerary and is a skin ulcer therapy. In skin care products it is used to help clear up skin blemishes and other skin irregularities.(CAS: 97-59-6/EINECS: 202-592-8)