Borax, also called sodium borate, is a common ingredient in cosmetics and skin-care products. It is considered safe to use on skin in concentrations of up to 5 percent, according to the Cosmetic Ingredient Review Expert Panel. But if you're using it for conditions involving injured or broken skin, the concentration of borax should be less than 5 percent.
Borax occurs naturally as a mineral called tincal. Its refined form is also known as sodium tetraborate decahydrate or disodium tetraborate decahydrate, which is why people prefer to call it borax. It is an odorless white powder, according to Borax.com. It is not well absorbed by intact skin, and is not classified as a skin irritant. However, it can cause serious eye irritation and should not be ingested.
Manufacturers put borax in skin-care products to keep germs from growing in them. Borax is also used to control the thickness of liquid products, as well as acidity. As an emulsifying agent, borax also prevents oils and liquids from separating. Otherwise a cream or lotion could separate, like an oil and vinegar dressing when you let it sit for a while. That would not be much fun to stick on your skin.
Borax is also a common ingredient in soap and bath salts because it's an effective skin-cleaning agent that dissolves readily in water. It makes sense that manufacturers also put it in laundry soap, laundry boosters and detergents so that it can clean your clothes as well as your skin. Borax is stable, nonflammable and nonreactive, according to SoapGoods.com. That's not all. Borax has many other uses in products besides cosmetics and soaps, and it can be prepared in different concentrations, depending on its use.
Borax can also be used as a multipurpose household cleaner and a buffer to protect chemical solutions against excessive changes in acidity. The list goes on. Borax is also an effective fire retardant, and stronger preparations can act as an antifungal, herbicide, or insecticide that can be used to kill different pests like roaches and ants. Of course, these are not the products you stick on your skin.