Does any1 know any valid science sites on the chemical reactions in cosmetics or the chemistry of it?

you can't put too much stock in any sites, but most college (.edu) or government (.gov) are fairly accurate. Unfortunately it usually pretty hard to find any detailed information for specific reactions on the internet. You would be better off looking for a book on the subject, or try e-mailing a cosmetics company. They may be able to help you with your questions or provide you with valuable contacts.

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