persistentone
Established Member
- Reaction score
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If we want to experiment with adding ingredients to a shampoo, hoping for some topical absorption, does it make a difference whether we use "food grade" chemicals - about 95% pure - versus "cosmetic grade" chemicals that are about 98% to 99% pure?
Why would we want to avoid food grade, which is much cheaper.
Why would we want to avoid food grade, which is much cheaper.