Glossary of Terms

Absorbers - Ingredients in sunscreens which create a chemical reaction to absorb UVR.
Actinic keratosis - A pre-cancerous condition often found in older, fair skinned people who have been chronically exposed to the sun.
Basal cell skin cancer - A cancer that develops at the lowest layer of the epidermis. It seldom spreads to other parts of the body but can be disfiguring if not treated early.
Broad spectrum - The term given to sunscreens which block both UVA and UVB.
Carcinogen - Substances known to cause cancer.
Collagen - A fibrous protein that helps give skin its strength and elasticity. Damage to collagen can lead to aging such as wrinkles.
Dermis - Just below the epidermis is the dermis, or the second layer of skin, which contains the blood vessels, lymph vessels and nerves, but is mostly made up of bundles of protein called collagen.
DNA - Deoxyribonucleic acid - an essential part of skin cells that is altered by ultraviolet radiation.
Elastin - A protein that helps skin to return to its original shape after being stretched.
Epidermis - The outer layer or the top layer of skin made up of overlapping cells, which create a protective layer.
Fake tans – A safer alternative to suntans, these lotions are usually made with vegetable dyes.
Keratin - A fibrous protein that helps form the epidermis.
Melanoma - The deadliest skin cancer. It is associated with aging and sun exposure, although it can develop at any time on anyone. It forms in the epidermis and dermis, and if it is not removed in its early stages, it will spread throughout the body.
Ozone - A naturally occurring gas that absorbs UVR.
Ozone layer - A thin shield in the stratosphere that is essential to preventing the sun's harmful rays from reaching the earth.
Peak UV hours - The hours between 10am and 4pm have the highest amounts of UVR.
Premature aging - Accelerated aging due to environmental factors such as overexposure to the sun.
Reflectors - Ingredients in sunscreens which are physical barriers that block or reflect UV rays away from the skin.
Reflected UVR - Many surfaces, such as sand, water, snow or building sides, reflect UVR which can be as bad for your skin as direct UVR.
SPF - Sun Protection Factor. A rating given to sunscreens to measure the amount of protection against UVB.
Squamous cell skin cancer - A skin cancer that develops in the uppermost layers of the epidermis and, over time in the squamous cell layer. It is easy to treat in early stages, but if ignored can be fatal.
Subcutaneous layer - The deepest layer of the skin which contains mostly fat.
Sunblock - Sunscreens that contain a physical blocker - zinc oxide or titanium dioxide -against both UVA and UVB.
Sunburn - The skin’s acute response to ultraviolet radiation.
Ultraviolet radiation – UVR. A portion of the energy spectrum produced by the sun and composed of UVA, UVB, and UVC.
UV Index - A method for forecasting peak UVR levels.
UVA - Sunrays measuring 315 to 400 nanometers. The longest and least powerful sunray.
UVB - Sunrays measuring between 280 and 315 nanometers, which cause the most sunburn.
UVC - The shortest sunray measuring between 100 and 280 nanometers. These rays kill microorganisms and are absorbed by the earth's ozone layer.
UVR – Ultraviolet radiation. A portion of the energy spectrum produced by the sun and composed of UVA, UVB, and UVC.