Field of Science

To Tattoo or Not To Tattoo

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Is it something you should do or is it taboo? What about a tattoo of a kazoo?

Okay, I'll stop now.

Recently I’ve been considering getting another tattoo or more work done to complement my existing tattoo. Its not terribly scientific like the Carl Zimmer’s Science Tattoo Emporium but it does mean something to me. I think I’ll probably wait until I finish my PhD, which means I’m looking at getting it in about a year.

Ignore my camera in the top left, the tattoo is too close to my shoulder making it very difficult to get it of of shot. Anyway, it's a raven.

One of the things I didn’t realise about getting a tattoo the first time was just how much mess it makes and how much blood there is. It doesn’t make any sense really given that I was completely aware a bunch of needle were going to repeatedly puncture my skin but, honestly, I’d never really thought about the blood. I can assure you if I had known I probably would have wussed out.

So I started looking at what exactly a tattoo is.

The dermis is the pink bit. Credit
For a tattoo to stick indelible ink must be inserted into the dermal layer of the skin. This gets it between the epidermis, which is the part that is constantly shed, and the blood supply. The introduction of a needle and ink into this area understandably activates your immune system and the damaged tissue becomes inflamed. Among the cells recruited to the damaged tissue are phagocytes and fibroblasts and both of these cell types begin the repair process. During repair the majority of the ink is incorporated into fibroblasts and scar tissue and remains a permanent fixture. Over time tattoos are degraded and so will eventually lose detail and also tend to fade if exposed to direct sunlight regularly.

Traditionally, tattoo colours and designs were limited by the skill of the tattooer, the tattooing equipment available and the pigments recoverable from nature. For this reason traditional designs are swirling or repetitive shapes done in only black ink. Black inks were made using ash but now a full range of colours are available through the generation of inorganic materials specifically designed for inks.

As tattoos become more and more popular, especially through shows like Miami Ink and tattooers become celebrities like Kat Von D it becomes easier to overlook the serious complications possible due to receiving a tattoo.

This isn’t to say you shouldn’t get one, only that you should be informed beforehand.

The establishment that did my tattoo smelt like a hospital, always a good sign. There are serious risks if the equipment is not sterilised properly and prison tattooing (where it would be unusual to find an autoclave available to inmates) carries with it an increased risk of HIV, hepatitis, herpes, tetnus and staph infections. It’s for this reason that if you get a tattoo you can’t give blood for the next 6 months in Australia. By that time I guess you would know if you have picked anything up.

Although rare, some people can have an allergic response to the tattoo itself. It’s believed to be rare because of the way the ink is sequestered into fibroblasts and fibrous tissue but if allergic to mercury and or nickel it can result in a tattoo that remains inflamed and continually weeps fluid. Typically, its red colour in tattoo designs that is more likely to give a reaction but at this stage the reporting of the issue is very low so for many it’s not a concern at all.

As well as allergic type reactions the body can straight up reject the tattoo and form a granulomas around the ink molecules. A granuloma is the body’s way of giving up and making a last ditch effort to attack a foreign invader. Lots and lots of immune cells throw themselves at the ink and fuse together to make a single giant cell and then it stays there with the ink trapped inside. Sometimes these can be felt as little lumps within the tattoo. Inflammation of the dermis and epidermis can also cause problems and tattoos, again rarely, have been linked to the development of eczema and other chronic skin conditions.

Its also worth asking where the ink came from as the cheaper inks have been found to contain known carcinogens and in a report from Europe they found that 40% had not been approved for cosmetic use and 20% of inks contained a known carcinogen!

And after all this there is one other possible complication. Again it’s rare but links have been made between burns and tattoos following magnetic resonance imaging or MRI.

Its been observed that thick black tattooed areas can result it burns following MRI due to the concentrated iron oxide used in the black pigments. The electrons in the iron oxide, which is magnetic, move in response to the moving magnetic field of the MRI, which generates an electric current. This current is resisted by your tissues causing them to absorb this energy and heat up. Due to the intensity of the MRI and therefore the generated current the heat can reach boiling point causing the water in the dermal layer of your skin to boil which can result in second degree burns!

Don't worry guys its not creepy at all when you do that. Also, is the Dr. Turk on the left?
I must stress that all these possible complications are rare and I’ve never met a person who has experienced any problems. I’m fully aware there are risks and they still aren’t going to put me off getting another :)

Now what should I add to it…
Any suggestions?

Wagle WA, & Smith M (2000). Tattoo-induced skin burn during MR imaging. AJR. American journal of roentgenology, 174 (6) PMID: 10845532
Tope, W., & Shellock, F. (2002). Magnetic resonance imaging and permanent cosmetics (tattoos): Survey of complications and adverse events Journal of Magnetic Resonance Imaging, 15 (2), 180-184 DOI: 10.1002/jmri.10049
Hartwig, V., Giovannetti, G., Vanello, N., Lombardi, M., Landini, L., & Simi, S. (2009). Biological Effects and Safety in Magnetic Resonance Imaging: A Review International Journal of Environmental Research and Public Health, 6 (6), 1778-1798 DOI: 10.3390/ijerph6061778


  1. I think you just killed off the remains of my faint and lingering desire to join the ranks of the tattoo'd. Given that I fainted while giving blood, this is probably a good thing. :p

    I think the main thing about it is just getting a good design. If you have a design you love, and that fits, and that you know you'll always move then go for it.

    Also, where are you going to get it? Back, or other shoulder?

  2. Oh no Rat I didn't mean to put you off! You can get gels and stuff to numb the pain if you so wish. That's what my wife did :)

    My current one is on my left shoulder blade and I think I'd like to place some context for the bird. Either more birds or a tree etc.


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