BTMS is indeed an ingredient that has a general safety score of 4 out of 5 in our ingredients database as well. ​ There are two main reasons why we still use BTMS in our formulations despite its potential irritating properties: ​ 1. We included it in the conditioner formulation, which is a product meant for our strands and is not supposed to be applied to the scalp. While BTMS is potentially irritating when applied for long on our skin, it is safe for our strands and a fantastic softener as well. ​ 2. This is the softening ingredients that is the easiest to manage at home without crazy chemistry equipments. Our goal is to allow anyone to be able to make their own products at home without having to get a full laboratory. Which is why we have selected this ingredient as being a decent compromise between convenience, safety and hair results.