Hi we're Megan and Marshall and we make Further Soap. The glycerin in this soap is derived from making biofuel. Marshall picks up used vegetable oil from some of the finest restaurants in LA, then processes it in our garage. The biofuel goes into our cars and the glycerin goes into our soap. Then we take the soap back to the restaurants that provided the oil and voila?. A perfect, sustainable circle. And now were bringing Further to you. We hope you enjoy using our fresh smelling soap as much as we like making it. Thank you for choosing to wash responsibly! Megan & Marshall Dostal FURTHER is biodegradable. FURTHER has a signature fragrance made from essential oils of bergamot, olive, and exotic grasses. FURTHER is made from the glycerin derived from the distillation of biofuel. FURTHER is never tested on animals.