the chemistry behind sunscreen

this page deals with the chemistry behind sunscreen lotions, explaining what makes them so necessary ...

Why wear sunscreen?

Your skin has an amazing ability to rapidly repair and heal most types of superficial damage, such as grazes and mild burns.

But, any injury occurring to your cells at a deeper layer - and that includes too much exposure to sunlight - can have a permanent effect on your skin tissue.

This is why repeated or prolonged exposure to the sun will produce a gradual - rather than immediate - deterioration in the quality of your skin.

Unless sunlight is deflected by the upper layers of the epidermis, the ultraviolet radiation strikes at the nucleus of your basal cells, altering the DNA within them.

Instead of renewing themselves perfectly, they will tend to divide defectively.

As the effect is cumulative, a small amount of sun exposure is okay, but repeated and intensive sunbathing over the years is not.

UVB waves tend to receive more criticism than the less energetic UVA waves.

But, in actual fact, both UVB and UVA can damage the skin

Unfortunately, many conventional sunscreens don't block UVA as effectively as they do UVB.

the chemistry behind sunscreen

What is the chemistry behind sunscreen lotions, and what should they contain?...

The chemistry behind sunscreen creams is fairly complicated, and ingredients vary from make to make. Find a list of permitted chemical compounds in sunscreen here.

Basically, what is in sunscreen are aromatic molecules conjugated with carbonyl groups.

These absorb high-energy ultraviolet rays, releasing them again as lower-energy rays and, in this way, stop UV rays from reaching your skin.

Because any part of the ultraviolet spectrum can damage your skin - in other words, both UVB and UVA waves - you should choose sunscreen lotion which protects against both.

Para-aminobenzoic acid (PABA) - one of the B vitamins - is a highly efficient UVB deflector.

And avobenzone, ecamsule and zinc oxide are all good at screening out UVA.