Thursday, March 7, 2013

Aging Tattoos



For older adults, tattoos were exclusively for sailors, convicts, bikers and indigenous groups. However, now, more than a third of 18-25 year olds in the USA have a tattoo adorning their body. Despite the recent tattoo boom there has been a dramatic decline in reports of infections that were associated with tattoos. But there are other concerns with tattoos, least of which is the aging of tattoos.

Aging skin changes shape, composition and elasticity and tattoos, because they are embedded in the skin, reflect these changes. Ian Eames at the University College London studied this change by developing a mathematical model of how tattoos ‘move’ with age.  There is physics, chemistry and biology.

Tattoos are ink suspended in a solution made up of ethyl alcohol, purified water, witch hazel, listerine, propylene glycol or glycerin (typically obtained from animal fats.) Tattoo inks can be made up of various particles. Although there are non-metallic colors (black which is made by burning animal bones down to charcoal), most colors can only be achieved using metals—heavy metals—including mercury, lead, cadmium, nickel, zinc, antimony, beryllium, chromium, cobalt, nickel, arsenic and iron.

In California after 1986--when Proposition 65 was passed--most tattoo parlors had to warn their patrons that tattoo inks contain heavy metals and are known to cause cancer, birth defects, and other reproductive harm. However some colors can only be achieved by using metallic ink. The metals are suspended in the skin by puncturing the top layer—some at 3000 punctures a minute—and leaving ink embedded within these punctures.

To protect itself the body's immune system reacts to this trauma by sending white blood cells to the area—causing visible redness. White blood cells attack the area and attach themselves to some of the heavy metals and clear them out of the body. The rest of the heavy metals are encased in protective cells and sealed within the skin.

With time, as these protective cells divide, or die, they exit the body taking with them the heavy metal that they have encased.  Laser treatment to remove tattoos speed up this process by killing these cells—and increasing the exposure to toxicity from newly released heavy metals. Like a fading colored cloth, the tattoo simply looses its detail both in terms of colors—some colors being more prone to fading than others—and definition. Intricate details in a tattoo are lost first. Also with older tattoos  the ink particles move deeper into the skin over time making the tattoo less distinct and harder to remove using laser treatment. Metallic tattoos also distort magnetic resonance imaging.

A study conducted in 2008 reported that up to 20% of the tattooed individuals regret their decision and many of them sought advice for tattoo removal. But the aging of tattoos is not related to physics, chemistry or biology, but is related to mindset. What you think is cool at 18-25 might not be so cool once you have grandkids. The aging of tattoos is related to leaving a permanent testament of a bygone era.

Mario Garrett, Ph.D., is a professor of gerontology at San Diego State University and can be reached at mariusgarrett@yahoo.com