Here are excerpts from a June 16, 2006 AP article that describes how many sunscreen lotions don't protect against skin cancer. The average person doesn't know this because when the Bush Administration came into office in 2001, they halted the proposed testing and regulation of sun screens.
Therefore, people are getting a false sense of security thinking that their SPF30 sunscreens are preventing skin cancer, when many lotions really are not screening out the cause of skin cancer.
"Doctors: Some sunscreens don't protect against cancer
By Linda A. Johnson Of The Associated Press
Think slathering on the highest-number sunscreen at the beach or pool will spare you skin cancer...? Probably not ...Sun tan lotions generally do a good job filtering out the ultraviolet rays that cause sunburn — UVB rays. But with sunburn protection, many people get a false sense of security that keeps them under the sun much longer. That adds to the risk of eventual skin cancer — both deadly melanoma and the less-threatening basal and squamous cell cancers.
And most sunscreens don't defend as well against the UVA rays that are more likely to cause skin cancer... That's true even for some products labeled ''broad-spectrum UVA/UVB protection.'' Often, product labels are confusing or bear misleading claims. For example, the SPF, or sun protection factor, refers only to defense against the less harmful UVB rays.
In 1999, the FDA announced tougher rules for sunscreen testing and label and ad claims, to take effect in 2001. But the agency put them on hold...Skin cancer incidence is climbing. There will be about 62,000 melanoma cases and 7,900 deaths this year, the American Cancer Society estimates."
http://www.mcall.com/news/nationworld/all-a5_sunscreenjun16,0,6717290.story