Sodium Laureth Sulphate, or some variation of it. Go check your bathroom and see how many products has this bad boy, typically anything that lathers will contain a version of this (SLES). During the manufacturing process of this chemical, its common for there to be traces of 1,4-dioxane, which is a known carcinogen, as well can cause developmental problems. Lastly, this chemical does not easily degrade, meaning that once its in our water, it will stay there for quite awhile.
How often do you wash your hands? Face? Hair? Dishes? Our exposure to the products that contain this chemical is quite high. Health Canada has not put it on the toxin list, but it is a priority for further assessment. Bet the punch and get it out of your homes.
This soap is, of course, basic. Many choose to only use one part castile soap, one part water, with added essential oils if you want to make it even simpler. Using a carrier oil in this helps keep your skin moisturized, and the honey is an added antibacterial for your hands and body.
Use any dispenser you like, adding all the ingredients. Adjust to your preference: I find that I typically will dilute the soap in the dispenser with water. It lathers very easily, and you only need the smallest amount to do the job. Adding water makes one soap pump go a long way.