The nonpartisan, nonprofit group known for watchdogging consumer products studied 952 sunscreens with a sun protection factor (SPF) of 15 or higher and discovered that 80 percent contain harmful chemicals and didn’t really protect skin from the most damaging rays of the sun . … A sunscreen ’s SPF indicates protection from the short-wave UVB rays that cause sunburn , but it’s the long-wave ultraviolet radiation (UVA) that is more directly linked to cancer. …
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Sun protection failures