I had a strange experience last spring. I started wearing sunscreen on the way to work. As soon as I hit the sun my eyes would start watering like crazy. I couldn't see and my nose joined in on the action. I thought it was pollen. One day I forgot to put the sunscreen on. My eyes did not water. I started doing web searches. The sunscreen I was using was supposed to be hypo-allergenic. Apparently the active ingrediate reacts with the sun. It was that reaction that was causing me so much grief. I try to wear uv protective clothing and use sunscreen that has only zinc oxide as the active ingrediant - like Lisa said. I'm rather fanatical about blocking out the uv effects, my favorite aunt died from skin cancer. Living in Tucson, during the summer you can actually feel the sun burning your skin. Its crazy.