Sunscreen May Not Be Enough Protection
< May. 14, 2008 > --
Sunscreens are one of the most popular protections people use as the summer sun
sizzles and threatens to burn their skin with harmful ultraviolet rays.
Sunburns are not only painful, but they also can lead to
skin cancer, the most prevalent form of cancer in the United States.
Yet, new research has led some to question the
effectiveness of many sunscreens.
A recent study by the Environmental
Working Group found that one in every eight name-brand sunscreens did not
protect against ultraviolet A (UVA) rays. These UVA rays have traditionally been
linked to tanning, but doctors now know they can cause long-term damage and skin
cancer. The SPF - or sun protection factor - rating currently placed on all
sunscreens only reflects the lotion's effectiveness in blocking ultraviolet B
(UVB) rays.
As a result of such research, the US
Food and Drug Administration (FDA) is in
the process of approving a new regulation that would set standards for testing
and labeling sunscreens for UVA protection as well as for UVB. These regulations
are sure to highlight many discussions during May, which has been designated
Melanoma/Skin Cancer Detection and Prevention Month.
The incidence of sunburns has increased in the United
States, a sign that many people are not using proper sun protection. A recent
study by the US Centers for Disease Control and
Prevention found that sunburn rates increased from 31.8 percent to 33.7
percent from 1999 to 2004.
Sunburn damage to the skin is a direct cause of skin
cancer, says Dr. Martin Weinstock, a professor of dermatology at Brown
University Medical School. "Most cancers in the United States are skin cancer,
and incidences are rising while the incidences of most other types of cancer are
remaining stable or going down," Dr. Weinstock says.
"The most important avoidable cause we know about is
exposure to ultraviolet radiation," he adds.
Sunlight is composed of the visible light that we can see,
and ultraviolet (UV) light that we cannot. There are two types of UV light - UVA
and UVB. While UVA rays are responsible for tanning and UVB for sunburn, both
can damage the skin and increase the risk of skin cancer.
Most skin cancers form in older people, on parts of their
bodies that have experienced more exposure to the sun, or in people who have
weakened immune systems.
The most deadly form of skin cancer is melanoma, which
forms in the skin cells that make the pigment melanin - often as a mole. The
US National Cancer Institute estimates there will
be 62,480 new cases of melanoma in the United States in 2008, and about 8,420
deaths caused by the disease. By comparison, there will be more than 1 million
new cases of non-melanoma skin cancers in 2008, with fewer than 1,000 deaths.
Experts recommend a multiple approach to protecting
yourself against harmful rays. "The American Cancer
Society has a slogan - 'Slip, Slop, Slap,' " Dr. Weinstock says."Slip on
a shirt, slop on some sunscreen, and slap on a hat."
But Kristan Markey, a research analyst with the
Environmental Working Group, a non-profit organization that works to
protect public health and the environment, says the effectiveness of sunscreens
is not as strong as one might think.
"We found that most sunscreens are not effective in
filtering out ultraviolet radiation or have problems with toxic hazards," Mr.
Markey says.
Not only do many sunscreens fail to protect against UV
radiation, but they also break down over normal usage and develop toxic
components, the group's study found.
Mr. Markey notes that sunscreen makers also make claims
that cannot stand up to the light of day. For example, even sunscreens that
boast "all-day protection" must be regularly reapplied to avoid skin damage, he
says.
Given the mandatory approval process, any new labeling
featuring the UVA ratings alongside the current SPF rating won't appear on store
shelves until 2009 at the earliest.
Until then, Dr. Weinstock says people need to continue to check themselves often
for changes in skin blemishes or moles, as a precaution.
"We do recommend that people do a thorough examination of their own skin once a
month, top and bottom, front and back," he says. "If they see spots that are
changing, ask for some advice from a medical professional.
Always consult your physician for more information.
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The US Centers for Disease
Control and Prevention offers suggestions to keep ultraviolet rays
from damaging your skin. Protection from sun exposure is important all
year round, not just during the summer or at the beach.
Any time the sun's ultraviolet (UV) rays are able to reach the earth, you
need to protect yourself from excessive sun exposure. UV rays can cause skin
damage during any season or temperature.
Relatively speaking, the hours between 10 a.m. and 4 p.m. during daylight
savings time (9 a.m. - 3 p.m. during standard time) are the most hazardous
for UV exposure in the continental United States. UV radiation is the
greatest during the late spring and early summer in North America.
Remember: UV rays reach you on cloudy and hazy days, as well as bright and
sunny days. UV rays will also reflect off any surface like water, cement,
sand, and snow.
Q: What exactly are "ultraviolet rays"?
A: Ultraviolet (UV) rays are a part of sunlight that is an invisible
form of radiation. UV rays can penetrate and change the structure of skin
cells.
There are three types of UV rays: ultraviolet A (UVA),
ultraviolet B (UVB), and ultraviolet C (UVC). UVA is the most abundant
source of solar radiation at the earth's surface and penetrates beyond the
top layer of human skin. Scientists believe that UVA radiation can cause
damage to connective tissue and increase a person's risk for developing skin
cancer.
UVB rays are less abundant at the earth's surface than UVA because a
significant portion of UVB rays is absorbed by the ozone layer. UVB rays
penetrate less deeply into the skin than do UVA rays, but also can be
damaging.
UVC radiation is extremely hazardous to skin, but it is
completely absorbed by the stratospheric ozone layer and does not reach the
surface of the earth.
Q: How can I protect myself from the sun's UV rays?
A: When possible, avoid
outdoor activities during midday, when the sun's rays are strongest. This
usually means the hours between 10 a.m. and 4 p.m. You can also wear
protective clothing, such as a wide-brimmed hat, long-sleeved shirt, and
long pants.
For eye protection, wear wraparound sunglasses that provide 100 percent UV
ray protection. And always wear a broad-spectrum (protection against both
UVA and UVB rays) sunscreen and lip screen with at least SPF (sun protection
factor) of 15.
Remember to reapply as indicated by the manufacturer's directions.
Also, check the sunscreen's expiration date. Sunscreen without an expiration
date has a shelf life of no more than three years. Exposure to extreme
temperatures can shorten the expiration date or shelf life of sunscreen.
Always consult your physician for more information.
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