Chemicals.
Getting sun burnt increases your chances of melanoma or other skin cancer
Moderately burned skin should heal within a week. While the skin will heal after a sunburn, the risk of skin cancer increases with exposure and subsequent burns. Even one bad burn in childhood carries an increased risk of skin cancer.
The ultimate risk of sun exposure with bare skin is skin cancer. Also, developing blisters and getting sunburned increases one's likelihood of developing skin cancer later in life.
Slightly oversimplified:UVA, helps skin make vitamin D, suntansUVB, sunburnsUVC, increases cancer risk
The purpose of a tanning bed is to give you a tan. Tanned skin is damaged skin - any dermatologist (or doctor of any kind) will verify that. The more often and deeply you tan, the greater your risk form skin cancer later in life. Tanning - in a tanning bead or elsewhere - cannot be said to "give you cancer", but it unquestionably increases your risk of developing skin cancer.
Anal sex greatly increases your risk of colon cancer
As the ozone layer dissipates due to pollution of the air, it allows harmful UV rays to pass onto the Earth, which greatly increases your risk for skin cancer.
If you get burned a lot, you are at greater risk for skin cancer later in life. To avoid risking cancer: Put on sunscreen, and if you get burned, wash it gently and place a cool damp compress on it, and use Aloe Vera or another treatment.
It is generally safe, but does put you at increased risk for skin cancer.
Being albino is not fatal. It is a skin disorder where the skin does not produce pigmentation. In extreme cases, albinos cannot go into the sun, as it drastically increases the risk of skin cancer.
If the ozone layer is destroyed it increases the risk of skin cancer, cataracts, and suppressed immune system.
increases in skin cancer, even in animals.