Tattoos are inflammations
If you’re thinking about getting a tattoo, you might want to learn about the science behind the art before you make your final decision. While on the outside, a tattoo is a beautiful and symbolic creation, on the inside, it is actually the result of a perpetual inflammatory process.
Maybe all you care about is whether or not it will hurt, but there is a lot more that can be learned about the tattooing process. Although humans shed 40,000 skin cells per hour, the TED-Ed video explains that tattoos remain permanent because they are not on the epidermis, but rather inside a second layer of skin: the dermis.
A tattoo machine punctures the skin continuously with a needle, depositing ink into the dermis, which is made up of collagen fibers, nerves, glands, blood vessels, and more.
Whenever the needle penetrates the skin — which could be up to 3,000 times per minute — it causes a wound which alerts the body to begin an inflammatory war to fight the intruding tattoo ink. White blood cells known as lymphocytes form the first line of defense; however, most of the pigmentation particles are too large for them to fight. Next, a different type of white blood cell — macrophages — come in and eat up the pigmentation particles. Some of these macrophages will carry the dye back to the lymph nodes, but many will simply remain in the dermis — dye and all — forever suspending your angel wings, Chinese character, or lover’s name in the second layer of skin.
In addition to existing inside macrophages, some ink particles simply float eternally in the gel-like matrix of the dermis. Still, others are eaten by dermal cells called fibroblasts, which remain in the dermis for their entire life cycles. Even when fibroblasts die, they get taken up by new dermal cells which hold both the old cell and the dye within it.
How, then, can tattoos be removed? According to Anne Laumann, professor of dermatology at Northwestern University, the best method of tattoo removal is laser treatment. In laser treatment, light targets a specific color and breaks up the ink particles of that color. By breaking up the ink particles, laser treatment creates particles that are small enough to be carried away by white blood cells. Unfortunately, this method does not always remove the entire tattoo.
Besides the tattooing process and tattoo removal, there is also a science to the ink used for tattoos. Traditional pigments were made from ground up minerals and carbon black, but today’s pigments can sometimes also include industrial organic pigments, vegetable-based pigments, or plastic-based pigments.
While the composition of your tattoo ink will inherently vary based on where you get your tattoo done, there are common compositions for various colors of ink. For example, black ink often includes carbon, logwood, or iron oxide; brown contains ochre; red has cinnabar (HgS) or cadmium red (CdSe), which are both known for toxicity. Consequently, it would be in your best interest to ask your tattoo artist about the chemicals they use in their inks to avoid allergic reactions or phototoxic reactions.
It has often been said that science is an art, but the biological and chemical intricacies behind tattoos suggests that art is a science, too.
Laser Tattoo Removal Breaks Up Ink Droplets For White Blood Cells To Carry Away
As soon as you get a tattoo, your white blood cells consistently fight to remove the pigments injected in this skin layer. This explains why tattoos begin to get less sharp and fade overtime, but not to the extent of being permanently removed. Laser tattoo removal zaps away the heavy metal in particles of ink since the white blood cells are much smaller than the ink particles to try and get rid of it on its own.
The laser helps the white cells carry the ink particles off to the liver so they can be disposed of. Tattoo removal does come with side effects. Color pigments like yellow #7, are known to break down into toxic and poisonous chemicals in the body on exposure to light either via UV light or laser removal. This can lead to these toxic substances traveling your kidneys and liver.
The Secret to a Tattoo's Permanence: The Immune System
The dye gets lodged deep in the skin thanks to hungry anti-inflammatory cells called macrophages.
tattoos are actually a complicated inflammatory process—a delicate balancing act between your body and the dye that's invading it.
It turns out your ethereal watercolored bird is kind of like an infection—and the reason it's permanent is because your body keeps on fighting it forever.
"Every time the needle penetrates, it causes a wound that alerts the body to begin the inflammatory process," the video explains. That signal sends immune system cells racing to the site of the wound (or multiple wounds, in the case of the five-inch dragon breathing fire across your chest).
Special cells called macrophages come to the rescue, eating up the dye in an attempt to "clean up" the inflammation it's causing. The rest of the dye gets soaked up by skin cells called fibroblasts. The fibroblasts, along with many of the macrophages, stay suspended in the dermis in perpetuity.
FYI: WHAT MAKES TATTOOS PERMANENT?
AND HOW DOES TATTOO REMOVAL WORK?
Tattoo application uses a mechanized needle to puncture the skin and inject ink into the dermis or second layer of skin just below the epidermis. Since the process involves damaging the skin, the body responds with white blood cells which attempt to absorb the foreign particles and dispose of them in the blood stream.
"The reason pigment stays there is because the pigment particles are too big to be eaten by the white cells, so they just sit there," Laumann says.
The problem with tattoos is exactly what makes them so appealing--their permanency. "If you have the name of your boyfriend on there and then you marry somebody else, that's a problem," Laumann says.
Tattoos also tend to become problematic with age. Ink can become blurred if injected too deeply into the skin, causing the pigment to migrate beyond the intended area. Fading and distortion due to changes in body shape are also common problems with tattoos. Permanent makeup--or tattoos that resemble eyeliner or other makeup--is a prime example of how these problems can lead to dissatisfaction years after the ink is applied because skin sags and changes shape with age.
"The problem with that is as you get older the shape of the fold of the skin changes," Laumann says. "So not only does it bleed a bit because the pigment moves gradually over time and so those will tend to become sort of smoky edges, but also the whole line might become a little distorted over the years."
"The big problem with tattoo removal is that it's really hard to get the whole tattoo out," Laumann says. "Using a laser often leaves a coloration afterward, I mean it's really hard. People get frustrated because it takes them so long and laser treatments are expensive."