Last summer, we wrote two back to back articles explaining why sunglasses are a summertime necessity. Aside from being iconic fashion statements, sunglasses are all about protecting your eyes from harmful UV rays. It might seem like we drone on about the topic, but we really cannot stress it enough: UV rays can be dangerous and we will ALWAYS recommend sunglasses, not just to help you look cool, but also to keep your eyes safe from UV rays and shaded from super bright sunshine. But as dangerous as it is, UV light is also unavoidable. The actions you take to protect your body are important, but no matter what, UV light will be there.
Contrary to what we like to talk about, there are some good things that come from UV light and that’s exactly what we’re going to talk about today! So slather on your SPF 50, grab your favorite sunnies, and enjoy this brief explanation poolside (as you practice social distancing)!
First: UV light, or ultraviolet light, is completely natural. UV is part of the bigger electromagnetic spectrum. All forms of energy give off radiation in waves, and these waves exist on a spectrum that measures how these waves change. Everything from radio waves to microwaves, WiFi and cellular technology, to the colors we see, to radioactive materials exist on this spectrum. UV is no different. The sun gives off three types of UV rays along with other rays from the spectrum and sends them all our way. But the Earth’s ozone layer does an efficient job of filtering out UV-C and most UV-B rays, allowing little UV-B and most UV-A rays past our atmosphere. Things only get dangerous for us if we’re exposed to too much UV-B and/or UV-A rays over an extended amount of time. Anyone who has spent a summer afternoon at Tahoe knows exactly what this results in. But the good news is that UV rays play an important role in our lives in three different ways.
On the body
This comes with the fair, if not obvious warning. Please don’t expose yourself to the sun for extended amounts of time. Getting a bad sunburn is just a mild reaction compared to more serious conditions like melanoma and retinal scarring and damage. But in reasonable doses (along with at least SPF 15 sunscreen), your body benefits from exposure to UV-A rays. UV-A rays allow your body to naturally produce Vitamin D.
Vitamin D is responsible for absorbing calcium to strengthen bones, help muscles and nerves work properly, and boost your immune system. It has even been researched for helping people overcome depression. And the best part is that it can be naturally produced through our skin. When you go out sun tanning, UV-A rays react to a Vitamin D precursor in your skin, creating a chemical that travels through the liver and kidneys to eventually become Vitamin D3. Having a healthy amount of Vitamin D in your body can help prevent diseases that affect your bones, like rickets in children and osteomalacia in adults. It can even protect your eyes from age-related degenerative conditions like cataracts, AMD, and glaucoma!
As a disinfectant
UV rays have picked up some positive media attention recently for the very same reason we recommend people avoid it! UV rays aren’t just a problem for us if we get overexposed. UV light has long been used as a disinfectant, making it an ideal candidate for study to disinfect hospitals and workplaces when they’ve been exposed to COVID-19. No, this isn’t the “sunlight will cure it” bologna. (Also, to reiterate: that’s bologna. Sunlight won’t kill it. But wearing a mask, social distancing, and washing your hands regularly will certainly help deter it.) Instead, it works because bacteria and viruses are highly sensitive to direct UV exposure.
UV light, at a basic level, can kill cells by dismantling DNA. On a microscopic level, this is what makes it so dangerous for us to be overexposed to it. UV-C rays specifically have such high energy they can do this very quickly. Thankfully the ozone layer of our atmosphere protects us from UV-C exposure. But UV-C lamps have been used for years as a way to sterilize equipment that would otherwise harbor bacteria and viruses.
Recently, hospitals and workplaces have employed the use of robots equipped with UV-C lamps to go through any empty room and neutralize bacteria and viruses. It can do so very quickly, leaving a hospital room clean within a couple of minutes. These robots are meant to pick up where humans leave off, keeping areas clean and stopping COVID-19 from spreading.
UV-C lamps are even making their way into personal gadgets, too! Companies like PhoneSoap and Larq are using UV-C lamps in their products to clean themselves or clean your personal belongings. PhoneSoap, for example, looks like a mini sun tanning booth for your phone. Pop your phone in, close the lid, and it goes to work, using the UV-C lamp to safely rid your phone of bacteria. Meanwhile, Larq water bottles use UV-C lamps in their lids to clean and disinfect the nooks and crannies that are hard to reach when people go to clean them.
For solving crimes
Every crime show in recent memory has this kind of scene: a dark room, illuminated only by a UV lamp that picks up evidence around the room. Granted, UV lights don’t magically light up evidence the same way tv shows may portray it, but there is some truth behind the dramatic scene. UV light is being utilized more and more every day to solve crimes! It’s thanks to UV light’s partner: fluorescence.
Without fluorescence, UV is nothing. Because UV rays are invisible, they literally can’t shine a light on anything. But when combined to any material that is fluorescent, the UV light reacts to it and leaves behind a very visible glow. In some cases, this is a method used to show authenticity of documents, like driver’s licenses and currency. But in a crime scene, chemicals designed to make certain traces fluorescent tell a story when they combine with UV light. These chemicals, known appropriately as fluorescent agents, react to proteins and oils that come from our bodies to make them fluorescent and visible to specialized lamps called forensic light sources. One of the best ways this is used is for fingerprints! The old-school dust and tape method doesn’t hold a light compared to UV! When UV and fluorescence partner up, fingerprints show up brighter and more complete than previous methods.
Look on the bright side
Again, we really can’t stress it enough: if you’re going outside, wear sunscreen or at the very least, your favorite pair of sunglasses. The dangers your eyes and your body faces when confronted with too much sun are all very serious. But the reality is that UV light can’t be totally avoided and can even provide some good if you’re being safe about it.