According to cosmetic chemist Ginger King, the common thread in most formulas is surfactants, which are also found in shampoos. What makes a brush cleaner truly effective specifically on brushes and makeup tools starts with the ingredient list. To get those tools squeaky-clean, you first need to find the right brush cleaner. Furthermore, legendary makeup artist Bobbi Brown says that the cleaner the brushes, the better they will work on your face - especially bigger, base-makeup tools like sponges and foundation brushes. Dermatologists recommend that scrubbing down our tools regularly in order to prevent bacteria buildup, which can lead to breakouts. Did you know that you should be cleaning your makeup brushes and sponges at least once a week? Yep, that's right.