Posting this as sort of a warning.  My household has done some searches over time for homemade detergent recipes.  A number of them included a suggested ingredient of “Fels Naptha Soap.”  Looked into it because there are a lot of unhealthy ways to make soap, varying in degree.  This particular soap contains a Benzene derivative.  Definitely not on the list of things you want to absorb through the skin, or get into your clothes.