Foods that contain petroleum-based dyes are usually ultra-processed and, as a result, they have food labels. These dyes are usually listed on the ingredient label, typically near the end, with names like “Red 40,” “Yellow 5,” or “Blue 1.”

The U.S. Department of Health and Human Services and the U.S. Food and Drug Administration have released further details of their plans to remove all petroleum-based synthetic dyes from the nation's food supply.