The vast majority of tattoo inks sold in the United States are contaminated with unlisted ingredients that can cause serious health issues, including organ damages, according to a recent study.

The study, published in the Analytical Chemistry journal on Feb. 22, investigated nine different brands of tattoo ink common in the United States, from minor to major brands.

Out of the 54 inks of the nine brands analyzed by researchers, 45 (83 percent) were found to contain "unlisted additives and/or pigments," the study stated.

"Major, unlisted adulterants include polyethylene glycol, propylene glycol, and higher alkanes. Many of the adulterants pose possible allergic or other health risks."

Over half of the inks contained unlisted polyethylene glycol, which causes organ damages following repeated exposure. Fifteen inks contained propylene glycol, a potential allergen. Some contained a compound called 2-phenoxyethanol that posed health risks to nursing infants while other inks were contaminated with an antibiotic used to treat urinary tract infections.

"Taken together, the results from this study highlight the potential for a significant issue around inaccurate tattoo ink labeling in the United States," the study stated.

The research was unable to identify whether unlisted ingredients were added unintentionally or whether the manufacturer was provided with contaminated materials. It is also unknown whether the manufacturer incorrectly labeled the inks.

Risks associated with tattooing usually focus on skin cancer and reaction to the pigments. However, ink additives can be dangerous as well, including having negative impacts beyond the skin. If a person with a tattoo starts experiencing reactions, unlisted ingredients can make it challenging to ascertain what reaction is happening and why it is occurring.

"We're hoping the manufacturers take this as an opportunity to reevaluate their processes, and that artists and clients take this as an opportunity to push for better labeling and manufacturing," said John Swierk, an assistant professor of chemistry at Binghamton University who is also an author of the study.