SUN DANGERS
There are many misconceptions about the sun, which has contributed to the explosive increase in skin cancers and melanoma.First a little background…
The sun is a giant ball of radiation, and is constantly emitting radiation that travels through space, our atmosphere and reaches the very ground we walk on. The sun emits ultraviolet light. This is shorter wavelength than visible blue or violet light and is very damaging, yet totally silent and invisible. The sun produces three different wavelengths of radiation: short (UVC), medium (UVB), and long (UVA). Each of these has specific characteristics and different effects on your body.
UVC is mostly absorbed by the ozone and oxygen in the atmosphere. Very little reaches the earth.
UVB is the medium wavelength radiation that is partially absorbed by the atmosphere, but the portion that makes it to the earth’s surface is very damaging and can easily result in a burn. Sunscreens use Sun Protective Factors, or SPF, to quantify how much UVB protection they have.
UVA is the longer wavelength UV radiation that is not absorbed in the atmosphere. Most sunscreens do not offer protection from UVA. UVA does not cause a burn easily but is more penetrating. It causes your skin’s immune function to weaken, premature aging of your skin , skin cancer and cumulative damage to your skin.
The Atmosphere
The only parts you need to be concerned with are the troposphere and the stratosphere. The troposphere is the layer of atmosphere that is closest to the earth’s surface. It is where we live and where all weather takes place.
The stratosphere is the next upper layer of the atmosphere. It contains 90% of the earth's ozone.
The Ozone Layer
Ozone is a type of gas that forms a layer or shield within the stratosphere. Ozone is chemically speaking O3, whereas oxygen is O2. Ozone is made when sunlight breaks O2 apart to singlet oxygen. This is a very unstable molecule and it quickly combines with O2 to form O3. Ozone makes life possible on earth, for without it, we would all be fried. The ozone layer blocks most of UVC and a portion of UVB, thereby protecting us. This Ozone layer is concentrated between 6 and 30 miles above the earth’s surface. This type of ozone is called good ozone.
There is also a bad ozone. This is the gas that is made up of air pollution and lingers in the troposphere (the layer of atmosphere we live in). The ozone that makes up urban smog is a danger to our health.
Bad ozone is a health HAZARD. Good ozone is life-saving.
The good ozone layer has suffered damage from man. Pollution, pesticides, industrial and manmade chemicals have drifted up to the ozone layer and damaged it. Chlorofluorocarbons (CFC's) are extremely toxic to ozone and were widely used in industry and commercial use, but now are very limited. These CFC's are especially toxic to the ozone layer because they drift up to the stratosphere and break down the ozone present.. When CFC's break down ozone they release chorine, which is toxic to ozone. The chlorine free radical causes a chain reaction whereby a single atom of chorine can destroy more than 100,000 ozone molecules.
The Ozone Hole
British scientists measuring the ozone layer over Antarctica during the 1980s were shocked to learn of extremely low levels of ozone. They discovered that this resulted from manmade chemicals. Chemicals that contain Chlorine (CFC's), Bromine, Halogen and Nitrogen oxides are especially damaging to the ozone layer. CFC's were used in a variety of industrial and commercial purposes including air-conditioning, refrigeration, solvents and aerosols. The Nitrogen oxides are the result of combustion reactions that occur with various forms of transportation.
Scientists in the 1980’s became aware of the damage to the ozone layer and many countries adopted new measures in order to prevent further damage to this life-saving layer. The peak damage to the ozone layer will occur from the present through 2010. Scientists believe that by actively taking measures that limit ozone-depleting substances, the ozone layer can repair itself. Unfortunately, it is a long process and thought to take a half-century to complete. Currently, there are holes in the ozone layer that allow the sun’s most damaging rays to reach the earth. In 2000 NASA discovered a hole over Antarctica that shocked the scientists by its sheer size. The hole comprised more than 28 million square kilometers. This is more than 3x the landmass of the United States.
What Determines Your Exposure To UV Damage?
Several factors, including:
Time of day- Noon is the worst as the sun’s rays have the shortest distance to travel to the earth’s surface. UVB is at it’s highest at noon.Time of year- Due to the sun’s angle with the earth changing during seasons, the intensity of UV radiation changes. It is the worst during the summer months.
Latitude (Location)- the sun's rays are strongest at the equator as the sun is closest to the earth and has the shortest distance to travel. Unfortunately, the ozone layer is thinner in the tropics and this adds to the UV exposure.
Altitude- the higher the altitude the more UV radiation exists. This is because less atmosphere exists to absorb the UV radiation.
Stratospheric Ozone-The current state of the ozone layer determines how much UV radiation is absorbed. This is constantly changing.
Reflection- The sun's UV rays are easily reflected off snow, water, grass and sand. This means you can receive UV radiation by reflection even if you are in the shade.
Weather conditions- Cloud cover reduces UV levels but UV radiation still penetrates through the clouds. It can cause a burn and certainly adds to cumulative skin damage and skin cancer. The damage to your eyes is greater on a cloudy day because your pupils are larger, permitting more UV and reflected UV to enter your eye.
Safe sun is a serious matter. You should take measures to protect yourself at all times. Just as you should always wear a seat belt, you should always make sure you are protected from the sun. Even one sunburn can dramatically increase your risk of melanoma—the most deadly form of skin cancer.
Take These Measures
- Avoid the sun as much as possible-especially between the hours of 10am and 3 pm.
- Wear sun protective clothing with a tight weave that covers as much of your body as possible. Wear sunglasses that wrap your eye. Wear a broad rim hat, preferably with a 4-inch or wider rim.
- Use Dr. Levine’s Ultimate Sun Block™.
What Can You Do To Protect Yourself From The
Sun's Harmful Rays?
- Physical Barrier protection- Stay inside during peak periods. Wear protective clothing at all other times. Use Dr. Levine's Ultimate Sun Block™.
- Stay out of the sun during peak hours, which is 10am-3pm. Do not assume before 10 or after 3 is safe. UVA is strongest at these time and is more penetrating. You still need protective clothing and Dr. Levine's Ultimate Sun Block™.
- Do not leave the house without sun block. Even incidental exposures during the day i.e., driving, walking from the car into the store, and walking the dog all contribute to cumulative sun exposure and all the risks associated with it.
Begin protecting your body's largest organ today by ordering Dr. Levine's Ultimate Sun Block™
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