Benzoyl Peroxide is one of the 4 approved ingredients for treatment of Acne under the Acne Topicals OTC monograph. The others are salicylic acid, sulfur and resourcinol.
The regulations are very specific. If you are using BPO in a product and any of your labeling references your product as a acne treatment, in any way, you are required to register your product as an OTC drug with the FDA, your labeling must be in compliance with that required under the Acne OTC Monograph, your product must be manufactured in an FDA OTC-registered facility and there are very specific protocols for testing your product.
You can use these ingredients in a cosmetic product … for instance, salicylic acid can be incorporated as an exfoliant, as a pH adjuster, as part of a preservation system, but if your product is marketed as a cosmetic, you cannot reference acne or acne treatment in any way in your labeling or advertising. You also face the possibility that your product may be considered as both a cosmetic and a drug from a regulatory perspective.
Good luck marketing Benzoyl Peroxide as an ingredient in a skin lightening product!
The only “loophole” so to speak that I can think of is if you only sell your product to professionals (ie: those skilled in its use … estheticians and dermatologists) then there are exemptions regarding some of the regulations, but manufacturing in a facility that is not OTC-registered is not an option, it just affects your compliance with labeling requirements.