OMG, David...

It makes sense, though. If you don't wait for an aerosol spray to dry fully, it's not surprising it would be flammable. The propellants usually are flammable. My DH loves aerosol sunscreen.
As for safety and efficacy, keep in mind, your skin may be a barrier that keeps you from dissolving, but it absorbs what you put on it, too. Sunscreens are chemicals.
