UV RadiationProject UVRAYdiant

Raffles Girls’ School (Secondary)

How the SUN sees you…

http://www.youtube.com/watch?v=o9BqrSAHbTc

CLASSIFIED BY WORLD HEALTH ORGANISATION:Group 1 carcinogen (the highest-level designation for carcinogens), meaning that “there is enough evidence to prove that it can cause cancer in humans”.

Skin Cancer

3 MAIN TYPESOF UV RADIATION 3

1 UVA Rays • Accounts for 95% of the UV radiation reaching the Earth’s surface. • Penetrates the skin more deeply than UVB rays, causes

premature ageing. • 30 to 50 times more prevalent than UVB rays though less intense.

UVA UVB

epidermis

dermis

UVB Rays2• Chief cause in skin reddening and sunburn. • Plays a key role in the development of skin cancer by

causing direct DNA damage. • Plays a contributory role in skin ageing and wrinkling.

After UV overexposure

3 UVC RaysMost damaging type of UV radiation, but it is almost completely blocked by Earth’s ozone layer.

UV INDEX• Singapore has one of the world’s highest UV indexes, averaging at

12. • An average person is at extreme risk of harm from unprotected sun

exposure.

Source: http://app2.nea.gov.sg/weather-climate/weather-information/uvindex

EFFECTS OF OVEREXPOSURE TO UV RADIATION

• UV rays damages the eyes as more than 99% of UV radiation is absorbed by the front of the eyes.

• Lead to chronic effects such as cataracts and macular degeneration, and can ultimately lead to blindness.

• Melanoma can also develop in the eye.

Eyes

Eye disease

Suppression of the Immune System• UV Overexposure may suppress proper functioning of the

body’s immune system and the skin’s natural defences. • Reduces skin’s ability to protect against pathogens.

Immune Suppression

• Spending long times outdoors without using UV protection may cause sunburn.

• Reddening of the skin due to increased blood flow in the skin, which is a result of dilation of the superficial blood vessels in the dermis.

 

Skin—Sunburn

Sunburn

• Dryness, wrinkles, accentuated skin furrows, sagging, loss of elasticity, and mottled pigmentation.

• Largely irreversible. • Cumulative exposure to UV radiation over the course of a

lifetime greatly increase the risk of contracting skin cancer such as: Melanoma.

Skin—Premature Ageing

Premature Ageing

Various Types of Skin Cancer:

Cumulative exposure to UV radiation over the course of a lifetime greatly increase the risk of contracting skin cancer such as:

1) Actinic Keratosis 2) Basal Cell Carcinoma 3) Squamous Cell Carcinoma 4) Melanoma

Identifying Symptoms of skin cancer

Identifying Skin Cancer Symptoms

Most early melanomas are asymmetrical: a line through the middle would not create matching halves. Common moles are round and symmetrical.

The borders of early melanomas are often uneven and may have scalloped or notched edges. Common moles have smoother, more even borders.

Common moles are usually a single shade of brown. Varied shades of brown, tan or black are often the first sign of melanoma. As melanomas progress, the colours red, white, and blue, may appear.

Early melanomas tend to grow larger than common moles - generally to at least the size of a pencil eraser.

UV PROTECTION

• Use sunscreens of SPF 30 and above.

• Apply sunscreen sufficiently and reapply every 1 hour.

• Look out for the label “Broad-spectrum”.

Sunscreen

• Cover up with caps/hats, especially when UV index is high.

• Broad-brimmed hats provide more UV protection.

• Shield sensitive skin on head and neck.

Caps/hats

Umbrella• Use umbrellas to

reduce UV exposure, especially on a sunny day.

Sunglasses• Use sunglasses to

reduce the amount of UV radiation reaching the eyes, reducing the risk of contracting eye diseases.

Attire • Wear sun protective

clothing with Ultraviolet Protection Factor (UPF).

• Wear bright or dark-coloured lustrous clothes.

• Wear tightly-woven, loose-fitting clothes.

SHADE• Attempt to seek

the shade between 10am - 4pm, where UV radiation is the

strongest.

“Skin cancer can take 20 to 50 years to surface, so it’s

never too early to start prevention”

~Quoted from The Straits Times

Extra resources for your own reference:1. http://app2.nea.gov.sg/weather-climate/weather-

information/uvindex 2. http://app2.nea.gov.sg/training-knowledge-hub/weather-

climate/uvradiation-uvindex 3. http://www.who.int/uv/intersunprogramme/activities/

uv_index/en/index3.html 4. http://www.cancer.org/cancer/cancercauses/

sunanduvexposure/skincancerpreventionandearlydetection/skin-cancer-prevention-and-early-detection-what-is-u-v-radiation

5. http://www.hpb.gov.sg/HOPPortal/dandc-article/9244