Sun Sun ExposureExposure

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 (“pre-malignant”)

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.

T F

2. Use a sunscreen with sun protection factor of 15 or more if outdoor s during the midday.

T F

3. Melanoma incidence has been steadily rising, affecting people of all ages.

T F

4. Farm workers are continually at risk of developing skin cancer of the head, face, ears, or neck.

T F

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

Answer Key1. T2. T3. T4. T5. T