When a cluster of skin infections in upstate New York last fall led back to one tattoo artist, local public health officials took the usual step of investigating the artist's hygiene practices. They found that all of his equipment and methods were sanitary, but the nationally distributed ink he had been using, even in unopened bottles, wasn't.
Soon, similar investigations in Colorado, Washington and Iowa turned up harmful strains of bacteria in three other brands of ink. At least 22 skin infections across the four states were linked to contaminated ink, according to research reported Wednesday (Aug. 22) in the New England Journal of Medicine.
The offending pathogen in the New York outbreak was identified as Mycobacterium chelonae, a relative of the bacteria behind tuberculosis and leprosy that is commonly found in tap water. Though M. chelonae is usually harmless to people with normal immune systems, when it's escorted beneath the skin by a tattoo needle, it can cause a painful rash that can last for months, requiring strong antibiotic regimens and sometimes surgery to eradicate.
According to the Centers for Disease Control and Prevention (CDC), past tattoo-related Mycobacterium infections likely arose from the use of unsterile water as a diluting agent in ink. And because the ink that caused the New York outbreak was "gray wash," pre-diluted black ink used for shading, the CDC has speculated that its manufacturer may not have been using sterile water.
So should American adults, one of five of whom now reportedly sport indelible ink, be afraid to get a new tat? Is there any way to be sure that a given manufacturer's tattoo ink is sterile?
The answer to the second question is a definite no. Currently, there is no FDA regulation requiring that tattoo inks be sterile, so a consumer only has a company's or an artist's assurance to go on. It is also worth noting that although a number of the color pigments used in tattoo ink have been approved by the FDA for use in cosmetics, not a single one has ever been approved for injection into the skin. [Are Tattoos Risky?]
Because reporting is voluntary, there is not good data on how often tattoo-related skin infections occur, but if one decides to play the odds and join the millions of Americans who are already inked, there are a few precautionary steps that he or she can take to decrease the chances of an infection.
Along with watch-dogging artists during tattooings to ensure that they use sterile water for dilution and cleaning, the CDC recommends that a consumer only use tattoo parlors registered by local jurisdictions and request inks that are manufactured specifically for tattoos. If an infection does occur, the CDC advises seeking medical advice and notifying the tattoo artist as well as the FDA's Medwatch program.
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