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Danger of UV to Homo Sap?

  1. Dec 21, 2004 #1

    Nereid

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    In another thread there's a discussion of the wavelength limits of the human visual system.

    A question has arisen re the damage that UV can have on the eye; specifically by wavelength and intensity.

    Can anyone help? There's tons of material on the internet, but how to judge what's authoratitive?
     
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  3. Dec 21, 2004 #2

    Monique

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    What exactly do you want to know? Radiation is absorbed by the eye and UV radiation at short wavelengths of 290-320 nm (UV-B) is readily absorbed by DNA and induces thymine dimers: a particular DNA mutation. Also, since it's ionizing radiation, free radicals are produced, which are also damaging.
     
  4. Dec 21, 2004 #3

    Nereid

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    Thanks Monique.

    UV longer than 320nm - what sort of damage does it cause to eyes? E.g. cataracts?

    High intensity light - of just about any wavelength? - e.g. staring at the Sun will damage your eyesight (how? what specifically is damaged?). Since UV isn't 'visible' (except just 'blue' of 'violet') except maybe at high intensity (the blue receptors do apparently have some response at short wavelengths, but <1% of that at the peak sensitivity), what sort of damage would you be doing to your eyes if you looked at a very bright UV source, e.g. at 380nm, or 370nm? Would the UV do more damage than (say) the same intensity (and duration) of 'visible' light (e.g. 500nm)?
     
  5. Dec 21, 2004 #4

    Monique

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  6. Dec 21, 2004 #5
    I believe the primary effect of UV overexposure is an increased risk of developing cataracts. Keep in mind that cataract development is a slow process that occurs over several decades. Staring at a UV source isn't going to give you a cataract right away.
     
  7. Dec 21, 2004 #6

    Monique

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    For literature: http://www.pubmed.com search for 'cataract uv radiation'.

    Here's a recent abstract:
     
  8. Dec 21, 2004 #7

    Monique

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    A review on epidemiological studies on cataracts and uv radiation:
     
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