Melanoma and the Environment
Melanoma is a type of cancer in skin cells that produce the pigment called melanin. It is the most dangerous but least common type of skin cancer. If this type of skin cancer is found early, it can be cured. However, melanoma can spread through the body much more quickly than other types of skin cancers and can cause death.
Between 65 and 90% of melanomas are caused by exposure to ultraviolet (UV) radiation from sunlight. Small amounts of UV radiation are good for people and needed for the body to produce vitamin D. But, too much exposure to the sun's rays can cause skin damage such as sunburn, wrinkles, and skin cancers. Peoples' behavior in the sun is believed to be a major reason for the rise in skin cancer rates, including melanoma, over the last few decades.
Exposure and Risk
Most melanomas are caused by exposure to ultraviolet (UV) radiation from the sun. Everyone is exposed to UV radiation from the sun. However, a growing number of people are being overexposed to sun rays and other sources of artificial UV radiation used in industry and other settings such as indoor tanning (using a tanning bed, booth, or sunlamp). When UV rays reach the skin's inner layer, the skin makes more melanin, the pigment that colors the skin. It moves toward the outer layers of the skin which causes a tan. A tan does not indicate good health. A tan is a response to injury, because skin cells are signaling that they have been hurt by UV rays by producing more pigment. People burn or tan depending on:
- their skin type,
- the time of year, and
- how long they are exposed to UV rays.
People with the following risk factors may be more likely than others to develop melanoma:
- a lighter natural skin color,
- family history of skin cancer,
- a personal history of skin cancer,
- exposure to the sun through work and play,
- a history of sunburns early in life,
- a history of indoor tanning,
- skin that burns, freckles, reddens easily, or becomes painful in the sun,
- blue or green eyes,
- blond or red hair, and
- certain types and a large number of moles.
For more information, visit CDC's Division of Cancer Prevention and Control.
Protecting yourself from ultraviolet (UV) radiation is important all year round, not just during the summer or at the beach. UV rays from the sun can reach you on cloudy and hazy days, as well as bright and sunny days. UV rays also reflect off of surfaces like water, cement, sand, and snow. Indoor tanning also exposes people to UV radiation.
You may be able to reduce your risk of melanoma by following these steps:
- seek shade, especially during midday hours,
- wear clothing to protect exposed skin,
- wear a hat with a wide brim to shade the face, head, ears, and neck,
- wear sunglasses that wrap around and block as close to 100% of both UVA and UVB rays as possible,
- use sunscreen with sun protective factor (SPF) of 15 or higher, and both UVA and UVB protection, and
- avoid indoor tanning.
For more information on melanoma: