Aminomethyl propanol and aminomethyl propanediol are substituted aliphatic alcohols that function as pH adjusters in cosmetic products at concentrations less than 10%; additionally, aminomethyl propanediol is a fragrance. Extensive oral toxicity data are reviewed, with fewer inhalation toxicity data. Dermal toxicity data are presented that demonstrate, for example, that a mascara with 1.92% aminomethyl propanediol does not cause dermal irritation or allergic contact sensitization, suggesting that the maximum reported use concentration of 2% in mascara would be safe. Although these ingredients are primary amines that are not substrates for N-nitrosation, they may contain secondary amines as impurities in finished products that may undergo N-nitrosation. These ingredients should not be included in cosmetic formulations containing N-nitrosating agents. The Cosmetic Ingredient Review Expert Panel concludes that aminomethyl propanol and aminomethyl propanediol are safe as cosmetic ingredients in the practices of use and concentrations as described in this safety assessment.