The Anatomy of a Sunburn

Last weekend, a dog licked me on the back and I nearly cried. That night, I slept in between two sheets of sandpaper, radiating red-hot heat, feeling the tight twisting pinch of a well burned back. The next morning, I think someone had sprinkled grains of sand on the bar of soap and somehow, the shower was raining down shards of molten glass, undoubtedly piercing through my skin and sheering it off in large strips. Or so it seemed.

But what exactly is a sunburn? I know it hurts. I know it involves the sun and I know it makes me look like an idiot, especially if I’m wearing sunglasses. But what is it? Here is the medical explanation—gloss over it, unless you’re a doctor or the details of medical jargon interest you:

Sunburn is a popular term applied to the marked erythema and pain that commonly follows injudicious sun exposure. A sunburn is really a delayed ultraviolet B-induced erythema caused by an increase in blood flow to the affected skin that begins about 4 hours and peaks between 8-24 hours following exposure [23, 30, 31]. The underlying cause of this vascular reaction is direct and indirect damage to specific cellular targets from photochemical reactions and the generation of reactive oxygen species [32]. Damage to DNA, and the activation of several inflammatory pathways, particularly involving prostaglandins [27, 33-38], are thought to trigger this reaction, ultimately leading to vasodilation and edema. Biologic response modifiers released by both keratinocytes and lymphocytes also play a role [39-55]. The development of erythema therefore implies that enough ultraviolet damage has occurred that inflammatory pathways have been activated. Erythema is probably best thought of as a total failure of sun protection, and is a marker for severe UV damage.

I had decided to spend the majority of the day doing yard work. I had let the grass grow to African savanna lengths, and I was certain I’d find a car underneath all of the overgrown bushes…not to mention the weeds, my God, the weeds. The two planters that encompass the patio had in them more weeds than plants, and I had had enough of it. The woodchips I put down specifically as a barrier to keep the weeds at bay had failed to do their job and instead allowed a multitude of weed varieties to break through the ground and choke out some of the existing plants. Curses.

I flipped on my fancy AM radio and got to work, eventually filling a very large trashcan with all kinds of plant trimmings, weeds, old wood bark and grass clippings. Since I knew that I would, the following day, be lounging around a pool, I wanted to layer on a nice protective pigment to hide the soft pale areas that I call the majority of my body. So, daftly I undoffed my shirt and let the sun shine down.

Unbeknownst to me, I had entered into the first stage of a sunburn…the first of many.

Ignorance: You spend all day not thinking about the fact that radiation from the sun has traveled 94 million miles through space to crash down on your skin, not surprisingly a not so tough envelope that holds together all of my insides. So there I am outside without sun block, innocently unaware that my skin is under attack. That, and you don’t feel it. What? Am I getting a little pink? Good, bronzy tan of a Grecian god here I come. But quietly, sunlight, specifically the waves from the ultraviolet part of the spectrum have been bombarding and killing skin cells all over my exposed body, especially my back, which was constantly bent over picking weeds, looking very much like a solar panel. But, I didn’t feel anything, just hot and thirsty from working.

Sensitivity: The sunburn never hurts until you are well away from whatever activity provided the burn. I had finished up in the yard. It was about six hours later as I hopped in the shower to wash up. I knew that I had a little too much sun and I began to think that maybe I should have used sun block. But, at that point, what can you do? The shower, at that point, wasn’t uncomfortable, but I did set the temperature a little lower than normal.

Denial: It wasn’t until a couple of hours later did I suggest to myself that I had a sunburn, but I didn’t think it was that bad. After all, I’m impervious to the maladies of mere mortal men, right? I wasn’t in the sun for that long. My shirt wasn’t off for that long. My patio kept me mostly covered. This pinky redness that is starting to resemble a lobster is going to fade nicely into a wonderful tan, to be the envy of everyone on the beach. Why no, I don’t spend my days inside in front of a computer, and yes, my darkened skin pigment suggests that I am healthy, that I exercise, that I’m the rugged outdoorsman I like to think I am.

Excruciating Agony: Then reality burst into flames. I’ve slaughtered billions of skin cells, wholesale murder, and my body wasn’t about to let me get away with it. The outer layer of skin on your body is called the epidermis. The outermost cells of the epidermis—the cells you see and feel on your arm, for example—are dead. But just below the dead cells is a layer of living cells, the malpighian layer (no, I had to look it up). These living cells continuously produce new dead cells to replenish your skin. The ultraviolet light is strong enough to penetrate through this layer of dead skin cells to begin killing off the layer of living cells underneath. You immune system comes to the rescue—as it normally does when there’s a plethora of dead skin cells to be dealt with—and allows white blood cells to flow into the affected area to remove the dead skin cells. As a result, your skin becomes tight from the swelling and red and warm because of the increased blood flow.

A couple of hours later, the nerve endings wake up to the fact that there’s a genocide of cells going on and it turns up the pain receptors. Specifically, the damaged and dying skin cells release a chemical that tells the pain receptors to punish me severely as some sort of lesson for the next time I think about going out in the sun without proper protection.

Then you get to realize exactly how many times the affected area comes into contact throughout a normal day. People hug you and drag sharpened nails across your back. A cotton shirt becomes a straightjacket of steel wool and something as simple as a car seat can inflict so much pain. So, it was silk shirts all around, which is why, for a couple of days, I looked like a Florida retiree combing the beach. And forget sleeping. I found that sleeping on my stomach was the only way to go, with the ceiling fan blowing directly down on me all night. The covers were kicked on the floor.

False Calm: Then the pain went away, about 24 hours later, and I was left with a strange calm, as if the worst was over and it would develop into a deep dark Columbian exile tan. But, alas, it was a false calm, as the storm was about to come.

Peeling: The next day, I noticed that the skin on my back had began to bubble in some places and stretch in weird ways in others. From behind, I looked like a leper. Then it happened. All of the skin on my back fell off, like a cascading ticker-tape parade of flakes of skin. All it took was one small area to give way and the rest followed with little trouble. It is equally gross and fascinating. I tried to peel away as large of pieces as I could, but it just wouldn’t hold in any respectable strips. The floor around the chair in my office and the bathroom sink looked like a moonscape.

Itching: Then came the itching. My skin was crawling with ants, on the underside, and I couldn’t itch it enough. The skin had almost all peeled away and what was left was a dried out layer of skin that only itched. Some parts were still burned and sensitive, but the rest crawled on my back like a wool sweater. It still does. Some would say that is my skin healing, rebuilding the damaged skin cells, but I say it is almost worse than the initial sunburn. It’s a toss up.

Discoloration: The final stage in the whole sunburn experience is discoloration, a two-tone back, one half the light pink of new skin and the rest of it a darker pink, what survived from the peeling. Also, I notice that I now have more freckles on my back, like the stars in the sky.

But the yard looks nice.

**While I was out working in the yard, I was frequently visited by the giant bumble bee in the lead picture. I don’t know anything about them, but I spent the afternoon wondering what a bumble bee hive looked like, and if it is any proportion to a regular honey bee’s hive, I suppose it is about the size of a small car.