Transcript Sun Exposure

Sun
Exposure
The learning goal:
Describe the effects from the
most prominent object in our
solar system – the Sun
Ultraviolet Radiation
 Primary Source =
natural: the Sun!!!
 Secondary Source =
artificial: tanning beds
Types of Ultraviolet Radiation
(UVR)
 UVA rays
 Weakest rays
 Impairs skin’s immune defense
 Causes melanoma, wrinkling, premature
aging
 Prevalent in tanning salons (which emit 5X
more UVA than natural sunlight!)
Types of Ultraviolet Radiation
(UVR)
 UVB Rays
 Stronger than UVA rays
 Affects skin’s outer layers
– Causes sunburn, skin aging, basal and squamous cell
cancers
 More intense during summer, closer to equator,
and at higher altitudes
 Prolonged exposure can also alter the immune
system!
Types of Ultraviolet Radiation
(UVR)
 UVC Rays
 Strongest, most dangerous rays
 Receive little attention from scientists and
doctors
 Are usually filtered by the ozone layer and
don’t reach Earth.
Youth are at risk because….
 They have high levels of sun exposure,
 They have low levels of sun protection,
 They have many outdoor jobs
– Lifeguards, tree planters, student painters,
camp counselors, etc.
 They work many spring/summer jobs when
they are out of school and the sun is
strongest!
How Skin Cancer is Caused
 UVR lowers the body’s immune system & makes
it hard to destroy defective cells
 Skin is tanned and/or burned via exposure
 Damage is done to cells and DNA
 Some cells die; some repair themselves by
getting rid of the damaged DNA
– Cells that cannot repair themselves, become defective
– Defective cells that are not destroyed slowly grow and
produce a tumor.
Three kinds of Skin Cancer
Exist!




Melanoma
Basal Cell cancer
Squamous cell cancer
Actinic/solar
keratoses (“premalignant”)
Did you know….
 1 in 5 Americans will
develop skin cancer?
 a person’s risk of
developing skin
cancer doubles if they
have > 5 sunburns?
 Women with basal
cell cancer TRIPLED
from 1976 – 2003?
 Women with
squamous cell cancer
QUADRUPLED from
1976-2003?
Melanoma
 Least common; most
serious
 Starts as flat brown
spot (~ freckle)
 Asymmetrical shape
 Common on upper
back in men; calf &
back in women
Basal Cell Cancer
 On sun-exposed areas
 Starts as blister-like
bump
 Can grow and
eventually becomes
crusted
 Usually spot is
clear/flesh colored;
can be pigmented
Squamous Cell Carcinoma
 Develops on
background of severe
sun damage
 Has scaling with pink
or brown coloring
 On sun-exposed areas
 Scaling can be picked
off but reforms
Actinic/Solar Keratoses
 Are “pre-malignant”
 Some will develop
into squamous cell
carcinoma
– The scaly lesions will
become harder,
elevated, and more
crusted
Negative Aspects
 Wrinkles
 Brown sunspots on your skin
 Aging
 Possible death
 Need for surgery or chemotherapy to
remove cancer
Why is it important to be
informed?
 Melanoma, the most dangerous skin
cancer, is almost always curable when it is
detected early.
 It can be prevented by being sun wise
 Early detection is key!
 The sun is fun, but can become dangerous
 Children need help protecting themselves
Barriers of Communication
 “It won’t happen to me” attitude
 Tans are seen as attractive
 Can be a result of childhood burns
 People are in the sun often enjoying sports,
beaches, parks, etc.
 Being protective is a nuisance to some
 Not being informed of the proper
prevention techniques
PROTECT YOURSELF!
 Reduce sun exposure
between 10am – 4pm
 Seek (or create your own)
shade
 Wear clothing that covers
your body
 Use sunglasses and wide
brimmed hats
 Apply sunscreen with
SPF15 or higher
 Use these precautions on
cloudy or overcast days
as well.
Did you know???
 Year-round sun protection is important
 The sun's harmful ultraviolet (UV) radiation can
penetrate many types of clothes?
 It can also go through automobile and
residential windows?
 It can damage your eyes, contributing to
cataracts, macular degeneration, and eyelid
cancers?
 When you're on snow or ice, your face and eyes
are at almost twice the risk of UV damage
because of reflected glare?
 The American Cancer Society estimates 8,790
deaths from skin cancer in 2011
Risk factors that increase the
chances of skin cancer…
 Unprotected exposure to UV radiation
 Fair complexion
 Family history
 Multiple or atypical moles
 Severe sunburns as a child
What are the signs of skin
cancer?
 Any change on the skin, especially in the size or
color of a mole or other darkly pigmented growth
or spot, or a new growth
 Scaly-ness, oozing, bleeding, or change in the
appearance of a bump or nodule
 The spread of pigmentation beyond its border
such as dark coloring that spreads past the edge
of a mole or mark
 A change in sensation, itchiness, tenderness, or
pain
Sun Exposure Quiz
1. Wear protective clothing that serves as a barrier between
the skin and the sun.
2. Use a sunscreen with sun protection factor of 15 or more if
outdoor s during the midday.
3. Melanoma incidence has been steadily rising, affecting
people of all ages.
4. Farm workers are continually at risk of developing skin
cancer of the head, face, ears, or neck.
5. Skin cancer cannot be associated with a single event,
such as a painful sunburn, but rather with the progressive
changes in the skin's makeup over years of sun exposure.
T F
T F
T F
T F
T F
Answer Key
1. T
2. T
3. T
4. T
5. T