Sassafras is a deciduous tree from Eastern North America that grows wild in deciduous woodlands and thickets on rich sandy well-drained soils. It can grow up to 25 metres tall with a spread of 16 metres but is very unlikely to reach this size in Britain where it commonly becomes no more than a small tree or large shrub. It will usually fit very well into a garden where it can be grown as a specimen plant in the lawn. It will also eventually make a good canopy tree for the sunnier edges of a woodland garden. Sassafras is still a commonly used herbal preparation with a wide range of actions. A tea made from the root bark is particularly renowned as a spring tonic and blood purifier as well as a household cure for a wide range of ailments such as gastrointestinal complaints, colds, kidney ailments, rheumatism and skin eruptions. The mucilaginous pith from the twigs has been used as a poultice or wash for eye ailments and is also taken internally as a tea for chest, liver and kidney complaints.
An essential oil obtained from the root bark is used as an antiseptic in dentistry and also as pain killer. The oil contains safrole, which is said to have carcinogenic activity and has been banned from use in American foods - though there is plenty of modern research which shows that it is less likely to cause cancer than alcohol. In large doses, however, the oil is poisonous, causing dilated pupils, vomiting, stupor, collapse and kidney and liver damage. The oil has been applied externally to control lice and treat insect bites, though it can cause skin irritation in some people. The essential oil is also used in soaps, the coarser kinds of perfumery, toothpastes, soft drinks etc. The volatile oil of sassafras is believed to be the major active constituent of the plant. This oil contains up to 85% of the terpenoid known as safrole. Safrole causes liver cancer when given to laboratory animals in high doses for long periods of time.5 Sassafras bark, sassafras oil, and safrole are currently prohibited by the U.S. Food and Drug Administration from use as flavorings or food additives. Human studies are lacking to verify the efficacy of sassafras for any condition. However, one case study has been published showing that sassafras acted as a diaphoretic in an otherwise healthy woman. While the amount of sassafras that could potentially cause cancer in humans remains unknown, one cup of strong sassafras tea is reported to contain as much as 200 mg of safrole, an amount that is four times higher than the amount considered potentially hazardous to humans if consumed regularly. The volatile oil of sassafras contains 80% or more of a chemical known as safrole. In the 1960s and 1970s, animal studies showed that safrole caused permanent damage to liver tissue, which resulted in liver cancer for a high percentage of the tested animals. Safrole has also been implicated in producing nerve damage. Cases of accelerated heart rate, hallucinations, paralysis, and other severe adverse effects have also been reported in humans who ingested sassafras.