Tattoos: because beauty is skin deep

Ever wondered how vibrant tattoo designs end up permanently etched onto someone’s skin?

Your skin has two main layers: the epidermis, the outer layer, and the dermis, the deeper one.

Tattoos live in the dermis. This layer is rich in collagen, a strong, fibrous protein that helps to hold the ink in place. That’s why tattoos last – the cells here are more stable than those in the epidermis which are constantly renewing.

Think of the dermis as a canvas. The tattoo artist is carefully using their machine to paint with ink, creating a masterpiece layer by layer. A tattoo machine is essentially a tiny, high-speed needle. It rapidly punctures the skin hundreds of times per minute, depositing ink into the dermis.

The process is essentially a controlled injury, which might sound painful, and for many people it can be! Your body treats a tattoo like a wound, kicking off the healing process and sending in immune cells to clean up the damage to the epidermis.

Some of these cells, called macrophages, actually engulf the ink particles. Others, called fibroblasts, help build new tissue and because the ink particles are too large for the body to remove completely, they trap some of the ink as well, resulting in a permanent design.

Over time, the body adjusts to the foreign ink, and the tattoo becomes a stable part of the skin.

While modern tattoos are relatively safe when done by a professional artist in a clean environment, they are always permanent – research has shown that tattoo ink particles even remain detectable in body after death, so choose your design wisely!

Sources:

Schreiver, I., Hesse, B., Seim, C., Castillo-Michel, H., Villanova, J., Laux, P., Dreiack, N., Penning, R., Tucoulou, R., Cotte, M. and Luch, A. (2017). Synchrotron-based ν-XRF mapping and μ-FTIR microscopy enable to look into the fate and effects of tattoo pigments in human skin. Scientific Reports, 7(1). doi:https://doi.org/10.1038/s41598-017-11721-z.

Union, P.O. of the E. (2017). Safety of tattoos and permanent make-up : final report. op.europa.eu. Available at: https://op.europa.eu/en/publication-detail/-/publication/e08d57a8-4fd0-11e6-89bd-01aa75ed71a1/language-en.

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