Anything that makes you shed old skin will make your face more sensitive to the sun, but you can put sunscreen over the AHA as well and that will keep your face protected. Other than that, I do not see how it would cause/promote cancer any moreso than anything else that you might use, eat, drink, breathe, etc. You live in a world where numerous things if not all things cause cancer, supposedly anyhow. It is not something that I would be overly concerned about.
[This message has been edited by Frogjive (edited 09-06-2003).]