Sun Exposure and Its Effect on Us

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Sun Exposure and Its Effect on Us

• Presentation by Sandra Gajewski
• Date 05/03/06

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Normal Skin

• Has 20 cell layers that are organized similar to
  a brick wall.
• Contains healthy amounts of collagen, a protein
  based substance, that makes up the skin
• Very flexible, with a shiny texture
• Lacks wrinkles and age spots (younger skin)

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Skin Damaged By the Sun

• Strong visibility of wrinkles, and age spots
• Drastic loss of flexibility resulting in
  sagginess caused from the Elastin in the skin to
  be torn down
• Strong affinity for cancer
• Layers decrease in number from
• 20 to 2

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More to it...

• Darkening of the skin
• Pigmentation of the skin
• Increases dryness, scaly-texture
• Too much exposure to the sun can cause a person
  to look a lot older than they are!

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What exactly is Collagen?

• It provides structural support for the skin,
  muscles, and tendons.
• It is found in fibroblast cells where it creates
  a fibrous network in which new cells can grow
• Accounts for 75 of the weight of the dermis
• Responsible for skins resilience and elasticity

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What is Elastin?

• Like Collagen, Elastin is a protein in connective
  tissue
• Helps skin resume its original shape after
  movement
• Composed of the amino acids, glycine, valine,
  alanine, and proline
• Made by linking tropoelastin protein molecules to
  make an insoluble, strong linked-array

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Why is the sun such a problem?

• Everyone is affected by the sun because we all
  need to be outdoors
• We all enjoy activities outdoors
• Skin cancer caused from the sun is one of the
  leading causes of death in the U.S. along with
  breast cancer, prostate cancer, and lung cancer
• No one seems to realize the importance of
  protecting their own skin, but only worry about
  their outward appearance

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A problem for us

• Most people receive 80 their lifetime exposure
  before the age of 18!!
• You think you might be fine, but the sun burn you
  receive this summer might take 20 years to become
  skin cancer!
• We are more in danger of the getting skin cancer
  than our older generations because of the
  depletion of the ozone layer.

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What is the ozone layer?

• Discovered in 1913 by Henri Buisson and Charles
  Fabry, French Physicists
• Also known as ozonosphere layer
• Located in the Earths atmosphere and has high
  concentrations of O3.
• Dobson Unit device used to measure the total
  amount of ozone in a column overhead

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How was the Ozone created?

• Sidney Chapman figured out the photochemical
  mechanisms that give rise to the ozone.
• Brief Explanation
• The ozone is created in a process where
  ultraviolet light strikes O2 molecules and splits
  them up to create ozone O3. Both molecules are
  unstable, and therefore, create a cycle, the
  ozone-oxygen cycle whenever the ultraviolet light
  strikes it.

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How the ozone helps our skin

• The Ozone helps prevent biological harmful
  ultraviolet radiation emitted from reaching our
  skin by absorbing it in the atmosphere.

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Ozone Depletion

• Depleted by free radical catalysts
• Nitric oxide (NO)
• Hydroxyl (OH)
• Atomic Chlorine and Bromine

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The Rays of the Sun Reaching Us

• When the ultraviolet light hits our skin and
  penetrates through, our skin responds in a 3
  stage process
• 1.) Melanin granules are oxidized by UV light
  and become darker.
• 2.) Melanocytes deeper in the epidermis begin to
  create new melanin granules for further
  protection.
• 3.) Melanin granules divide and produce more
  cells, but the damage has already been done.

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Common Cancers Associated with Skin Damage

• Basal Cell Carcinoma
• Enlarge slowly and can invade into neighboring
  tissue
• Most common on the face
• Closely related to Squamous Cell Carcinoma
• Melanoma
• Found in melanocytes
• Can spread to other tissue through the lymph
  system or through the blood

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Sun Protection Factor

• -Misunderstanding
• SPF 15, for example does not mean you can stay
  in the sun 15 minutes longer than without
  sunscreen
• What it does mean
• SPF 15- covers 80 of the suns rays
• SPF 10- covers 90
• SPF 20-covers 95
• SPF 40-97.5

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UVA , UVB, and UVC

• UVA rays- less energy, but penetrate the most
  into skin. These rays are best known for aging.
• UVB rays- most potent rays that reach the
  earth.These rays cause burns and ultimately, skin
  cancer
• UVC rays- Have the shortest wavelength, the most
  energy, but do not penetrate the earths
  atmosphere

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How we can protect ourselves

• Wear skin protection everyday! SPF 15, at the
  least.
• Wear proper clothing
• Wear UVA and UVB shielding sunglasses
• Try to stay in the shade as much as possible

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Readings

• Websites
• http//en.wikipedia.org/wiki/Ozone_layer
• http//www.maui.net/southsky/introto.htmlis
• http//www.skin-care.cl/skin-discoloration.htm
• http//coolshade.tamu.edu/fx.html