What Regulations Apply to Colorants?
If a colorant is not listed on 21 C.F.R. Part 176.170 (paper and paper board for aqueous and fatty food), how can it be used for such applications in a polymer?
As you point out, colorants listed in Part 176.170 of the Code of Federal Regulations (C.F.R.), Title 21, are cleared for use with paper and paperboard, if they comply with the specified conditions. The colorants that are explicitly cleared by the U.S. Food and Drug Administration (FDA) for use in polymers are listed in 21 C.F.R. Part 178.3297. In addition, FDA, in general, permits the use of inks in food-contact materials that are comprised of: substances listed in 21 C.F.R. Part 73.1 (Color Additive Petitions), color additives cleared for direct use in food, GRAS substances, substances that are the subject of a prior sanction, and substances that are separated from food by a "functional barrier." For more information, see the PackagingLaw.com article, The Use of Colorants in Packaging Applications: An Overview.