zeliciousz

I'm not a chemist. I'm not in natural sciences at all. But recently, on a backpacking trip, my buddy and I got into a discussion and wanted to get an answer from someone who knew what they were talking about. If I transfer sunscreen into a transparent container and put it in the sun, will the sun render the sunscreen impotent? Is it direct sunlight exposure that makes the sunscreen stop being effective? When I put it on my face, and it's exposed to the sun, it lasts an hour and then I have to reapply. If I store it in a transparent container, it is also exposed to the sun. Is that a bad idea? Second part: If it does in fact render the sunscreen impotent, is it just the layer that is exposed to the sun, or does the sun radiation permeate to the rest of the sunscreen in the bottle? Thanks for any input.