A new lawsuit claims that a chemical used in Skittles makes the multi-colored candy “unfit for human consumption.”

The suit was filed by consumer Jenile Thomas over the use of titanium dioxide, which produces Skittles’ vibrant colors. Mars, which makes Skittles, said in a statement, “While we do not comment on pending litigation, our use of titanium dioxide complies with FDA regulations.”

The use of titanium dioxide is allowed for coloring under federal regulations as long as it doesn’t exceed one percent of the food’s weight.

Thomas is seeking class-action status for all U.S. consumers of Skittles, saying they are, quote, “at heightened risk of a host of health effects for which they were unaware stemming from genotoxicity — the ability of a chemical substance to change DNA.”