Sun Protection Facts
How to Protect Your Skin From The Harmful Effects Of The Sun
Sunscreen or sunblock
is a lotion that is applied to reduce skin damage by blocking ultraviolet
radiation from the sun. The best sunscreens block both UV-A and UV-B
rays, both of which can cause sunburn.
Most sunscreens work by containing either an organic
chemical compounds that absorbs ultraviolet light (such as oxybenzone)
or an opaque materials that reflects light (such as zinc oxide), or
both.
Most people apply sunscreen when participating in
outdoor activities during the summer. However, some experts suggest
wearing sunscreen on a daily basis to prevent cumulative damage, and
to lower the risk of skin cancer. It is recommended that sunscreen
be applied 30 minutes before exposure to the sun.
The ancient Greeks used olive oil as a type of sunscreen.
However, this was not very effective. Throughout the early twentieth
century, H.A. Milton Blake, a South Australian chemist, as well as
several other inventors attempted to create an effective sunscreen
but failed.
It was not until 1944 that the first effective sunscreen
was invented. At that time World War II was in full swing and many
soldiers were getting serious sunburn. A pharmacist called Benjamin
Greene decided to create something that would save the soldiers from
the sun’s harmful rays.
In his wife’s oven he created a sticky, red
substance which he called "red vet pet". Greene tested it
on his own bald head. It didn’t work nearly as well as modern
sunscreens, but it was a start.
Greene then created a more user friendly sunscreen
which he began selling to customers in and around Miami. He founded
the Coppertone company and his sales boomed. The little protection
his product offered had customers enthusiatic. People were no longer
afraid of getting sunburn. In their eyes, the sun's harmful rays were
conquered.
Sunscreen has come a long way since its initial conception.
Modern products have much higher protection factors than Greene's
sunscreen, and modern products can also be water- and sweat proof.
But there are also negative effects. The plastic bottles that are
sometimes left behind on beaches are not biodegradable.
Also, a lot of people rely too much on the product
not understanding the limitations of the sun protection factor, assuming
buying anything over 30 will automatically prevent them getting burnt
no matter how long they can stay in the sun without protection. Too
much sunbathing is one of the major causes of skin cancer across the
world.
Sun protection factor
The SPF (sun protection factor) of a sunscreen is
a laboratory measure of its effectiveness. The higher the SPF, the
more protection a sunscreen offers against the Ultraviolet type B
radiation that causes sunburn, the formula
used to calculate an SPF is available here.
For example SPF 15 means that a user can nominally
remain in the sun 15 times longer than would otherwise cause them
to have sunburn. In real life the protection from a particular sunscreen
depends on factors such as the:
Skin type of the user
- Amount applied and if it is reapplied every 2 hours, while in
the sun
- Time of day and season
- Percentage of UV reflected or scattered by the environment e.g.
snow or sand.
- Amount of sunscreen the skin has absorbed.
- The SPF is not a linear measure of the amount of Ultraviolet blocked.
A sunscreen rated 15 blocks 93.3% of UV, and an
SPF 30 sunscreen blocks 96.7%, according to the Australian
Radiation Protection and Nuclear Safety Agency. A 30+ SPF rated
sunscreen will protect against sunburn but that does not mean it
can be applied 30 times less often, or that users can stay out in
the sun for 30 times longer without skin damage.
The SPF is an imperfect measure of skin damage, because
invisible damage and skin aging is also caused by the very common
Ultraviolet type A, which does not cause reddening, or pain.
Normal sunscreen does not block UVA as effectively
as UVB, and an
SPF rating of 30+ may translate to significantly lower level of UVA
protection according to a study from 2003 by researchers funded
by the RAFT trust.
Some broad spectrum sunscreens do provide significant
UVA protection. UVA
also causes DNA damage to cells deep within the skin, according to
a 2004 study increasing the risk of malignant melanomas.
Due to consumer confusion over the real degree and
duration of protection offered labeling restrictions are in force
in several countries. In the United States in 1999 the FDA decided
to institute the labelling of SPF 30+ for sunscreens offering more
protection, and a similar restriction applies in Australia.
This was done to discourage companies making unrealistic
claims about the level of protection offered e.g "all day protection",
and because an SPF over 30 does not provide significantly better protection.
The following are the FDA allowable active ingredients
in sunblocks:
- p-Aminobenzoic acid (PABA) - up to 15 percent.
- Avobenzone - up to 3 percent.
- Cinoxate - up to 3 percent.
- Dioxybenzone - up to 3 percent.
- Homosalate - up to 15 percent.
- Menthyl anthranilate - up to 5 percent.
- Octocrylene - up to 10 percent.
- Octyl methoxycinnamate - up to 7.5 percent.
- Octyl salicylate - up to 5 percent.
- Oxybenzone - up to 6 percent.
- Padimate O - up to 8 percent.
- Phenylbenzimidazole sulfonic acid - up to 4 percent.
- Sulisobenzone - up to 10 percent.
- Titanium dioxide - up to 25 percent.
- Trolamine salicylate - up to 12 percent.
- Zinc oxide - up to 25 percent.
From Wikipedia, the free encyclopedia.
Sun Protection Resources
Sunscreens, Sunblocks
Sun Protection Tips
Sun Protection
Protecting your
Skin from the Sun
The Best
AntiAging Treatment is a Sunscreen
Taking Photos While
You're Protecting Your Skin
The Myths
and Facts of Vitamin D and Sun Exposure
