Food companies have been using artificial colors to make food more appealing for centuries. In the 1800s, an array of lethal compounds, including copper sulfate, lead chromate and arsenic were used. Colors made from coal tar (also used to dye clothing) became the norm by the 1900s.

But over the years, following reports of children being poisoned and rodents developing reproductive tumors, hundreds of artificial colors were banned,  including Violet #1 (once used in the U.S. Department of Agriculture’s own meat inspection stamp) and Red #2 (which is still allowed to be used in the coloring of orange peels).

Today, nine petroleum-based dyes have been tested and approved for use in food, and each batch must be pre-screened by the FDA—a fact that many see as a testament to their safety.

“There are a lot of things out there that people consume that the FDA doesn’t oversee at all,” notes Bonnie Jortberg, a registered dietitian with the University of Colorado School of Medicine. “I haven’t seen anything in the literature that would lead me to believe there should be great concern about food dyes.”