Sunscreen products such as sun tan lotion contain chemical components that reduce the amount of the sun’s ultraviolet (or UV) radiation that reaches the skin.
The active ingredients in sunscreen work by blocking the UV rays from the skin by reflecting them away or chemically absorbing them and converting the light energy into heat energy. The physical ultraviolet-reflecting sunblock components tend to be inorganic compounds such as zinc oxide or titanium dioxide, and those that absorb UV rays are commonly organic compounds such as aminobenzoic acid, avobenzone, oxybenzone, octisalate, and octocrylene.
Ultraviolet radiation in sunlight is known to cause sunburn, skin cancers and premature ageing of the skin, and good sunscreen products are an effective way to reduce exposure.