A consumer is suing candy maker Mars, alleging Skittles contain a "known toxin" that makes the rainbow candies "unfit for human consumption."

In a lawsuit seeking class-action status filed in U.S. District Court for the Northern District of California on Thursday, attorneys for San Leandro resident Jenile Thames said that Skittles were unsafe for consumers because they contain "heightened levels" of titanium dioxide.

Mars Inc. uses titanium dioxide to produce Skittles' well-known array of artificial colors. In 2016, the candy maker publicly shared its intention to remove titanium dioxide from its products in the coming years, the Thursday complaint noted – but titanium dioxide is still used in products like Skittles today.

In a statement sent by Mars to TODAY and several other news outlets, the company said: “While we do not comment on pending litigation, our use of titanium dioxide complies with FDA regulations.”

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USA TODAY reached out to Mars for additional comment Saturday.

According to the FDA's Code of Federal Regulations, "The color additive titanium dioxide may be safely used for coloring foods generally," but there are several restrictions – such as the quantity of titanium dioxide not exceeding 1% of the food's weight.

While the regulated use of titanium dioxide in food products is still legal in the U.S., it has been banned in some other countries, including throughout Europe. In May 2021, the European Food Safety Authority announced that titanium dioxide "can no longer be considered safe as a food additive" – noting the importance of genotoxicity concerns, for example.

Genotoxicity is the ability of chemicals to damage genetic information such as DNA. "After oral ingestion, the absorption of titanium dioxide particles is low, however they can accumulate in the body," said Maged Younes, chair of EFSA’s expert Panel on Food Additives and Flavourings, in a statement at the time.