Sundicator.net

An explanation of what sunscreens are and how to use them.

Sunscreens are important skin-care products used to prevent photoaging and skin cancer. Until recently it was believed that blocking UVB radiation and sunburn were the only measures needed to prevent sun damage. The SPF rating was developed to measure the ability of a sunscreen to block UVB radiation. Now we know that UVA radiation also contributes significantly to damaging the skin. These chemicals are used in sunscreens to absorb UVA radiation.

Benzophenones

The benzophenones, oxybenzone and dioxybenzone, are the second most commonly used components of sunscreens. They provide effective protection in the 320-340 nm portion of the UVA range (not the complete UVA spectrum). Oxybenzone is actually a more efficient UVB absorber and boosts the SPF when added to other UVB absorbers.
• Advantages – Does not stain clothing and does not cause skin irritation
• Disadvantages – Not water resistant

Avobenzone

Avobenzone (Parsol 1789) is the only chemical that absorbs the whole UVA spectrum at 310-400 nm. It does not provide any UVB absorption. There has been controversy about whether avobenzone actually breaks down in the presence of sunlight, but it appears that these claims have not been backed up with further studies.
• Advantages – Does not stain clothing and does not cause skin irritation
• Disadvantages – Controversy of stability in sunlight

Read all the tips here:
33 Sunscreen Tips