Sun exposure can be very dangerous if proper protection is not taken. Sunscreen is a necessary component of sun safety.
Effects of the Sun
There are numerous effects from the sun, many of them very dangerous.
Sunburn includes tenderness, pain, swelling, and blistering and may include fever, chills, and nausea. While there is no cure for sunburn, wet compresses, cool tub baths, and soothing lotions may help. If you have a bad burn, see your dermatologist. Wear sunscreen to protect against sunburn. Make sure the SPF is at least 15.
People who work or lay in the sun without sufficient protection get sagging cheeks and deep wrinkles that may make them look much older. The sun can also cause unsightly red, yellow, gray, or brown spots and scaly growths that may develop into skin cancer. Wearing sunscreen consistently can help protect your skin from premature aging.
Skin cancer is caused by too much sun, long-term exposure, and bad sunburns. More than 90% of all skin cancers occur on parts of the body exposed to the sun. The face, neck, ears, forearms, and hands are the most common places for skin cancer to develop. Skin cancer can also develop in the corners of the eyes. It is therefore important to always wear sunscreen and sunglasses that block 100% of UV rays.
UV radiation can damage the eye in both the cornea and lens. Long-term exposure can lead to cataracts and other eye disorders. Short-term exposure can burn the front surface of the eye, similar to sunburn on the skin. Wear sunglasses that block 100% of UVA and UVB radiation to protect your eyes.Immune System Suppression and Disease
Short periods of sun exposure can damage the human immune system and make the body more susceptible to infections and cancers. Also, some diseases can become worse with sun exposure. These include herpes simplex (cold sores), chicken pox, lupus, and certain genetic problems. Certain medications, such as antibiotics and antihistamines, can cause extra sensitivity to sun exposure. Be sure to consult your doctor when starting a new medicine before spending prolonged time in the sun.
Ultraviolet (UV) radiation comes in two main varieties: UVA and UVB. Both have been linked to skin cancer and a weakened immune system. UV radiation is a known carcinogen. Exposure to these rays can cause skin agin, skin color changes, and damage to the eyes. Precaution must be taken when exposed to these types of energy to protect and defend against long-lasting effects. Exposure to UV rays, and even sunburn, is possible even on cloudy days. Up to 80% of solar UV radiation can penetrate cloud cover. UV exposure is also greater at lower latitudes (near the equator) and higher altitudes. Snow, sand, and water increase sun exposure by reflecting UV rays. It is important to use sunscreen every day to protect skin against UV exposure. Eye damage can also occur due to exposure, making eye protection equally important.
Ultaviolet A (UVA) rays release energy throughout daylight hours and have the power to penetrate deep into the skin where they can do permanent harm to DNA. Additionally, they can cause damage to the elastic and collagen fibers that make skin supple and firm. UVA rays are not absorbed by the ozone, and up to 90% of visible skin aging is caused by UVA energy through sun exposure.
Ultraviolet B (UVB) rays are responsible for sunburns and are one of the foremost contributors to skin cancer. They are partially absorbed by the ozone layer and affect the top layer of skin. UVBs peak in intensity from 10 a.m. to 4 p.m. in the summer. UVB rays can be blocked by glass. Using sunscreen can help protect against sunburns and skin damage caused by these rays.
Sun Protection Factor (SPF)
Sunscreens work by absorbing and/or reflecting both types of UV rays. The FDA recommends using “broad-spectrum” sunscreens as they contain ingredients that protect against UVB and UVA rays. Always use a sunscreen that has a Sun Protection Factor (SPF) of at least 15 as it provides protection for 93% of UV radiation. An SPF of 30 provides 97% protection. Consult the chart below for the effectiveness of SPF.
Sunscreens contain both chemical and physical ingredients. Many sunscreens contain UVA-absorbing avobenzone and benzophenone in addition to UVB-absorbing ingredients. The physical compounds titanium dioxide and zinc oxide reflect, scatter, and absorb both UVA and UVB rays. Consult the chart below for ingredients and the protection they offer.
Quick Tips to Block UV Rays
Cover Up. Wear tightly-woven clothing that blocks out light. Try this test: Place your hand between a single layer of the clothing and a light source. If you can see your hand through the fabric, the garment offers little protection.
Use Sunscreen. A Sun Protection Factor (SPF) of at least 15 blocks 93% of UV rays. You want to block both UVA and UVB rays to guard against skin cancer. Be sure to follow application directions on the bottle.
Wear a Hat. A wide brim hat (not a baseball cap) is ideal because it protects the neck, ears, eyes, forehead, nose, and scalp.
Wear UV-Absorbent Sunglasses. Sunglasses don’t have to be expensive, but they should block 100% of UVA and UVB radiation.
Limit Exposure. UV rays are most intense between 10 a.m. and 4 p.m. If you’re unsure about the sun’s intensity, take the shadow test: If your shadow is shorter than you, the sun’s rays are the day’s strongest.
Environmental Protection Agency. (2004 May). A guide to the UV index. Retrieved March 9, 2010 from http://www.epa.gov/sunwise/doc/uviguide.pdf.
Environmental Protection Agency. (2007 Oct.). Prevent eye damage. Retrieved March 9, 2010 from http://www.epa.gov/sunwise/doc/eyedamage.pdf.
Environmental Protection Agency. (2006 Sept.). Sun screen: The burning facts. Retrieved March 9, 2010 from http://www.epa.gov/sunwise/doc/sunscreen.pdf.