How to protect ourselves from UV radiation?

It is necessary to know how to protect ourselves from UV radiation, both indoors and out. Protection from sun exposure is therefore important all year round, not just during the summer or at the beach. Ultraviolet (UV) rays can reach you on cloudy and hazy days, as well as bright and sunny days. UV rays also reflect off of surfaces like water, cement, sand, and snow. Always seek the shade outdoors, especially during the hours between 10 a.m. and 4 p.m. daylight savings time.


There are some easy options for sun protection as recommended by Centers for Disease Control (CDC):
1) Seek shade, especially during midday hours

2) Wear clothing to protect exposed skin
3) Wear a hat with a wide brim to shade the upper body parts
4) Wear sunglasses that wrap around and block as close to 100% of both UVA and UVB rays as possible
5) Use sunscreen with protective factor (SPF) 15 or higher, and both UVA and UVB protection

Diagram: Tips on protection against sunlight. (Erwin. 2010)

Most sunscreens work by absorbing, reflecting, or scattering sunlight. Since the advent of modern sunscreens, a sunscreen’s effectiveness in blocking UV rays has been measured by its sun protection factor (SPF). It indicates how long it will take for UVB rays to redden skin when using a sunscreen, compared to how long skin would take to redden without the sunscreen. An SPF 15 sunscreen screens 93 percent of the sun’s UVB rays; SPF 30 protects against 97 percent; and SPF 50 screens against 98 percent. As maintained by the Skin Cancer Foundation, SPFs of 15 or higher are necessary for adequate protection from UVA and UVB since both of these rays are relatively harmful.

Treatment Options for Skin Cancer

There are several things to take into consideration when discussing treatment options for a patient with skin cancer: the type of skin cancer, the stage and location of it, and the individual’s age and overall health. For instance, people with small basal cell carcinomas may only require simple treatment. However, unlike basal cell carcinomas, squamous cell carcinomas have a greater tendency to spread, and eventually may require more treatment. The three kinds of treatment used for most skin cancers include: surgery, chemotherapy, and radiation therapy.

Surgery is the most common treatment to skin cancer. One of the several surgical methods is simple excision that involves cutting out the tumor with a margin of surrounding normal skin to ensure it is completely removed. Another surgical method that freezes and kills the cancer cells is known as cryosurgery. This method makes use of liquid nitrogen which has a temperature of 196 degrees below zero centigrade. The extreme cold immediately kills the tumor, which eventually falls off like a scab after the area thaws. Cryosurgery is typically used for small or superficial skin cancers. For cancers that have grown beyond the outer layer of the skin, laser surgery would be used. Laser surgery uses the highly focused beam of light from a laser to destroy cancer cells.

Diagram: Cryosurgery. (Cure Genital Warts, 2010)

Chemotherapy is referred to as treatment with anti-cancer drugs given to destroy or control cancer cells. The anti-cancer drugs in cream or lotion form are often applied to the skin of the patient with skin cancer. Such topical chemotherapy is for superficial tumors which have not advanced beyond the top layer of the skin. Although topical chemotherapy usually does not produce nausea or other body-wide side effects, it does cause redness and inflammation in affected area of the skin. Another form of chemotherapy, known as systemic or body-wide chemotherapy, may be given in a pill, injected into a muscle, or intravenous form through a needle in a vein. Side effects are common in this treatment, but they can generally be controlled. This treatment is normally used only for metastatic cancer.

Diagram: A patient doing radiotherapy. (National Nursing Review, 2009)

Radiation therapy, or radiotherapy, uses a special kind of energy carried by invisible rays or particles to kill cancer cells or inhibit their growth. This therapy is usually used for cancers that occur in areas difficult to treat with surgery. These include cancers on the ears, eyelids, and the tip of the nose.

How does UV radiation cause skin cancer?

By damaging the skin’s cellular DNA, excessive Ultraviolet (UV) radiation produces genetic mutations that can lead to skin cancer. UV rays react with a substance called melanin that is found within the skin. Melanin plays a role in the first defense system to protect against the sunlight by absorbing the dangerous UV rays which can cause serious damage to our skin. Sunburn occurs when the amount of UV exceeds the level of protection that the skin's melanin can provide. However, a small amount of exposure to sunlight is healthy and pleasurable. Predisposition to skin cancer can be hereditary, meaning that it is passed through the generations of a family through genes.

Basically, there are two different ways by which UV radiations could cause skin cancer:
• By damaging the DNA in skin cells, causing the skin to grow abnormally and develop benign or malignant growths.
• By weakening the immune system and compromising the body’s natural defenses against aggressive cancer cells.

UVA rays have longer wavelengths. They penetrate deeper into the dermis and suppress the immune system to interfere with the ability of immune system to protect against the development and spread of skin cancer. Signs of UVA exposure include premature aging of the skin such as wrinkling and age spots. Long-term exposure can cause damages to the skin's connective tissues, leading to premature aging.

UVA may also aid in the development of skin cancer. According to the research studies done by scientist, UVA does not cause significant damage in areas of the epidermis which is the outermost skin layer where most skin cancers occur, UVA damages the skin cells called keratinocytes in the basal layer of epidermis where most skin cancers occur.

Diagram: A tanning booth. (Amber Desire, 2009)

UVA is used by tanning salon in the tanning booths. UVA is the dominant tanning ray, and we now know that tanning, whether outdoors or in a salon, can cause cumulative damage over time. The doses of UVA emitted from the high-pressure sunlamps in the tanning booth are as much as 12 times that of the sun. Based on the statistics, people who often visit tanning salons are 2.5 times more likely to develop squamous cell carcinoma, and 1.5 times more likely to develop basal cell carcinoma. According to recent researches, risk of melanoma is 75 percent higher for individuals who had first exposure to tanning beds in youth.

The UVB rays are the sun's burning rays and are the primary cause of sunburn. UVB rays have shorter wavelengths than UVA and are primarily responsible for sunburn and skin cancer. UVB rays can be blocked by window glass. UVB tends to damage the skin’s more superficial epidermal layers. It plays a key role in the development of skin cancer and a contributory role in tanning and photoaging. Its intensity varies by season, location, and time of day. Melanoma, the most dangerous form of skin cancer, is thought to be associated with severe UVB sunburns that occur before the age of 20.

Skin Cancer & Ultraviolet Radiation

Diagram: A healthy skin is undeniably an important element of healthy life. (My Healthy Soul, 2010)

Skin cancer is a type of cancer that forms in the skin tissues. Skin cancer has been the most common type of cancer in United States. Skin cancer that forms in the lower part of the epidermis is called basal cell carcinoma whereas squamous cell carcinoma is the skin cancer that forms in squamous cells. These two most common types of cancer are more highly curable as compared to the third type of skin cancer – melanoma, which is more dangerous.

Diagram: An example of melanoma skin cancer. (Health Line, 2011)

Most skin cancers form in older people on parts of the body exposed to the sun or in people who have weakened immune system. The UV light contained in the sunlight causes the cells to mutate and begin to grow and divide more quickly than normal cells do. These abnormal cells will clump together to form tumors in other parts of body and thus causing cancer to occur.

UV radiation is part of the electromagnetic (light) spectrum that reaches the earth from the sun. Apart from the sun, UV rays can also come from the tanning beds and sunlamps. UV rays are an invisible kind of radiation due to their shorter wavelengths than visible light which make them invisible to the naked eyes. The three types of UV rays include Ultraviolet A (UVA), Ultraviolet B (UVB), and Ultraviolet C (UVC).

Diagram: How ultraviolet rays travel to the Earth. (Nathan, 2009)

UVA has the wavelength of 320-400 nm which is the longest among them. UVA is the most common type of sunlight present at the earth’s surface, and reaches beyond the top layer of human skin. It is believed that UVA rays can damage connective tissues and eventually increase a person’s risk of skin cancer. On the other hand, UVB rays are less common at the earth’s surface since most UVB rays are absorbed by the ozone layer. Although UVB rays do not reach as far into the skin as UVA rays, they can still be damaging. With even shorter wavelengths which are extremely dangerous, most UVC rays are absorbed by the ozone layer and do not reach the earth’s surface.