There are artificial versions that are often used in the making of root beer. There is also a natural extract available which has the harmful oil removed as well, but the artificial versions are still used for root beer in most cases.
Safrole was found to be a weak cancer causing agent in rats, which led to the ban on the oil in the US. A study done in 1977, however, found that it may not have the same effect on humans. Despite this, the FDA, as well as The European Commission On Health And Consumer Protection still holds to the assumption that it is carcinogenic (cancer causing).
Safrole was used in many different products in the past, from drinks such as root beer and sassafras tea to soap and perfume. It can also be found naturally in various common spices and herbs such as cinnamon and basil. Commercially available culinary sassafras oil is usually sold with safrole taken out.
So how harmful is this oil? The Lawrence Berkeley National Laboratory estimates that it has effects on humans similar to risks posed by breathing indoor air or drinking municipally supplied water, so there seems to be no need to worry.
