The Environmental Working Group's dogged campaign for safer, more effective sunscreen seems to be having an impact on the industry. The 2009 investigation of 1,571 products shows that 70 percent of sunscreens now contain strong UVA filters, compared to 29 percent last year. (Most sunscreens protect from the sun's UVB rays. An ideal sunscreen blocks both UVA and UVB rays and doesn't break down in the sun). The bad news? Much UVA protection is still too weak to save your skin. Here are the best and worst beach and sport sunscreens, according to the advocacy group.