Dr. Bronner's Tea Tree Castile Liquid Soap is made with pure organic tea tree oil. Completely biodegradable and vegetable-based, Castile Liquid Soaps have been called the "Swiss-army knife" of cleaning - usable for just about any cleaning task. These simple, ecologically formulated soaps are gentle enough for washing body, face or hair, but also powerful enough for tasks like dishwashing, mopping, laundry and even pest control.