8397fa35_ening_ingredients___WHITERskin__2
[0] Mequinol [1] Monomethyl ether of hydroquinone [3] Can be effective when used in conjunction with tretinoin [4] Yes, in lower concentrations. [2] 
Cytotoxic to melanocytes (like hydroquinone)
List of commercial skin lightening / skin whitening ingredients | WHITERskin
2