Word: ultraviolet
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...world now knows that danger is shining through the sky. The evidence is overwhelming that the earth's stratospheric ozone layer -- our shield against the sun's hazardous ultraviolet rays -- is being eaten away by man-made chemicals far faster than any scientist had predicted. No longer is the threat just to our future; the threat is here and now. Ground zero is not just the South Pole anymore; ozone holes could soon open over heavily populated regions in the northern hemisphere as well as the southern. This unprecedented assault on the planet's life-support system could have horrendous...
...vital gas being destroyed is a form of oxygen in which the molecules have three atoms instead of the normal two. That simple structure enables ozone to absorb ultraviolet radiation -- a process that is crucial to human health. UV rays can make the lens of the eye cloud up with cataracts, which bring on blindness if untreated. The radiation can cause mutations in DNA, leading to skin cancers, including the often deadly melanoma. Estimates released last week by the United Nations Environment Program predict a 26% rise in the incidence of nonmelanoma skin cancers worldwide if overall ozone levels drop...
Excess UV radiation may also affect the body's general ability to fight off disease. Says immunologist Margaret Kripke of the M.D. Anderson Cancer Center in Houston: "We already know that ultraviolet light can impair immunity to infectious diseases in animals. We know that there are immunological effects in humans, though we don't yet know their significance...
...almost certainly originated nearly 3.5 billion years ago as a mechanism for repairing the DNA of bacteria. Because ancient earth was such a violent place, the genes of these unicellular organisms would have been frequently damaged by intense heat and ultraviolet radiation. "Conjugation" -- the intricate process in which one bacterium infuses genetic material into another -- provided an ingenious, if cumbersome, solution to this problem, although bacteria continued to rely on asexual reproduction to increase their numbers...
...strangest products I encountered there was this lotion that came in a tube and is supposed to make you look tan without having to expose yourself to nasty ultraviolet rays. Is smearing chemicals on your skin any healthier...