Chemistry behind lip balm coloring based on skin pH I stumbled across an ad for a clear, colorless lip balm that purportedly tints your lips a shade of pink determined by your skin's pH.


  This balm stain applies on clear then reacts with your skin's pH levels, uniquely creating the perfect shade of pink lips just for you.


Out of curiosity (and the fact that I'm an easy target for marketing), I read further. The product contains the following ingredients:


Hydrogenated Polyisobutene
C12-15 Alkyl Benzoate
Diisostearyl Malate
Octyldodecanol
Dibutyl Iauroylflutamide
Dibutyl Ethylhexanoyl
Thylhexanoyl Glutamide
Isononyl Isononanoate
CI 45410
Chrysanthemum (a whole flower added to the bottom of the tube, presumably just to make it look nice.)


Other than CI 45410, I can't find anything on the above list that mentions anything about color -- and there's nothing listed that I think could change color based on pH.

Note: Some of the ingredients are very hard to find data for, but most seem to be thickening agents.

Does this clear lip gloss actually have the ability to change color based on pH or does the color come from the CI 45410? If it's from the CI 45410, what causes it to go from clear to pink?
CI 45410 (A.K.A. Phloxine B or acid red 92) is a pH dependent dye which is clear below about pH=4.1 and pink at pH>4. The formulation is mildly acidic and is neutralised by saliva upon application to become pink.  

(Thereby "uniquely creating the perfect shade of pink lips just for you.")