The FDA has approved nine synthetic color additives for use in food

See How Froot Loops Landed at the Center of U.S. Food Politics by Jesse Newman of The WSJ. Excerpt:

"The U.S. Food and Drug Administration has approved nine synthetic color additives for use in food, and said they are safe when used in accordance with FDA regulations. The FDA said the totality of scientific evidence shows that most children experience no adverse effects from eating foods with the added colors, though some evidence suggests certain children may be sensitive to them. 

Kellogg said its products and ingredients comply with all relevant laws and regulations. The company said more than 85% of its sales come from cereals that don’t contain colors from artificial sources."