22 Microbes Found in One-Third of Common Tattoo Inks in the US

American biologists have discovered 22 different types of anaerobic and aerobic microbes in a third of popular American brands of tattoo inks and permanent makeup.

Some of them can cause serious infections if they enter the skin, according to a report published by the press service of the American Society for Microbiology.

"Our measurements show that sealed, unopened tattoo ink bottles sometimes contain anaerobic bacteria that can thrive in oxygen-poor skin layers, as well as various aerobic microbes, suggesting that ink could be a source of infection caused by both species," said Kim Sungjae, a researcher at the National Center for Toxicology Research.

The scientists came to this conclusion by studying the properties of 75 popular brands of tattoo and permanent makeup inks sold in the United States by 14 different manufacturers of these pigments. While studying their properties, the scientists dissolved small amounts of ink, 1-2 grams in a medium for anaerobic or aerobic microbes, to see if this led to the emergence of bacterial environments.

The scientists' analysis showed that both microbes, including various forms of pathogenic bacteria, were present in 35 percent of the ink samples, including containers containing tattoo and makeup pigments that had been sealed by the manufacturer and never used for their intended purpose.

In these ink samples, the experts discovered 22 types of microbes belonging to 14 different genera of bacteria. The samples included several types of staphylococci, which can grow in an anaerobic environment and cause skin infections, as well as Cutibacterium acnes, which is linked to the development of acne and other forms of inflammatory skin diseases, and some infectious diseases.

“The rise in popularity of tattoos in recent years has been accompanied by an increase in the number of complications and reactions associated with the application of these designs to the skin,” concluded Kim Sungjae. “It is important to understand that not all of these complications are related to microbes, as some were caused by inflammation and allergies, as well as the toxic effects of the inks. However, the results of our measurements highlight the need for continuous monitoring of inks to ensure their safety.”