I am writing further to your post of May 31 "Cosmetics: Facing the (lack of) facts". I thought you may be interested in a recent report released by Friends of the Earth in Australia and the United States titled "Nanomaterials, sunscreens and cosmetics: Small ingredients, big risks".
Friends of the Earth wholeheartedly agree with the conclusion that you and Paula Begoun (to whom you refer in your post) have drawn, that the risks of nanoscale ingredients in cosmetics and personal care products remain poorly studied and poorly understood. However we believe the existing small body of toxicological evidence indicates the potential for harm.
Our report surveys the existing literature and calls for a moratorium on the release of cosmetics and personal care products that contain nanomaterials until we have regulatory oversight and comprehensive toxicological testing.
Friends of the Earth Australia Nanotechnology Project