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UV Light Causes Skin Cancer
Don’t laugh if you hear about kids hiding in their basement this summer. They might have been frightened by a recent report from Europe that liquid sunscreens don’t protect people from the sun’s harmful rays.
Researchers kept track of 631 children, some of whom used sunscreen and (46) . The researchers found that the kids who used sunscreen got more sun-caused moles than did the kids who didn’t use sunscreen. Kids with sun-caused moles are more likely to develop skin cancer later in life.
Did sunscreen harm the children Probably not, the researchers concluded. They believe that the children relied too much on their sunscreen and stayed in the sun too long. Sunscreen is still safe to use, say skin experts, as long as it is used sensibly.
Solar Cares
Using sunscreen sensibly is more important than ever. Why Skin experts like Martin Weinstock believe that (47) . Earth’s ozone layer appears to be getting thinner. Ozone is a gas. In the upper atmosphere, ozone blocks much of the sun’s harmful ultraviolet (UV) radiation. Polluting chemicals are thought to be destroying the ozone in some places.
Even though the world’s wealthy countries agreed to stop making polluting chemicals a few years ago, ozone is still disappearing. And that’s bad news, skin experts say, because UV light causes skin cancer, and skin cancer is the most common kind of cancer in the United States. More than a million new cases of skin cancer are showing up in the United States every year.
Scientists are looking at kids to reverse that trend. Why Because getting too much sun when you’re a kid seems to set the stage for getting skin cancer when (48) . According to Weinstock, three-quarters of all skin cancers might never develop if people under the age of 18 avoided overexposure to the sun.
Glaring Facts
What happens when skin meets sun Light rays, which come in varying wavelengths, strike the skin. Visible light consists of wavelengths (49) . Ultraviolet light consists of waves too short to be seen. UV light comes in several varieties, among them UVB and UV

• A. UVB wavelengths are slightly shorter than UVA wavelengths.
  Scientists once thought that UVB light was harmful and that UVA light produced a healthful tan. But opinions have changed. Scientists still agree that UVB light causes sunburns. But now they suspect that both kinds of UV light damage the DNA of cells.
  Moreover, scientists believe that either UVA light or UVB light or both weaken the body’s disease-fighting immune system. The body becomes less capable of repairing damaged cells, and such cells may go on to divide uncontrollably. In other words, (50)
  Three Little Words
  To help people avoid getting harmed by the sun, the American Cancer Society has summed up its advice in three words: Slip, Slop and Slap. The words are short for "Slip on a shirt! Slop on the sunscreen! Slap on a hat!"A. they may become cancerous
• B. people can see
• C. you’re older
• D. UVA is different from UVB
• E. sunlight is growing more hazardous
• F. some of whom didn’t