Pigments "Generally Recognised as Safe"
The use of colourants in plastics for indirect food-contact applications in the USA is controlled by the FDA and its requirements are laid down in regulation 21 CFR § 178.3297. This document is generally known as the 'GRAS list.
The FDA document gives a list of materials which may be safely used as colourants in the manufacture of articles, or components of articles, intended for use in producing, manufacturing, packing, processing, preparing, treating, packaging, transporting or holding food. Certain restrictions are also laid down as follows:
> The colourant must be used in accordance with current good manufacturing practice, including use levels which are not in excess of those reasonably required to accomplish the intended colouring effect.
> Colourants must conform to the description and use specifications laid down in 21 CFR § 178.3297. Should the polymer itself be subject to regulation, then it too must conform to the relevant specifications and limitations which may be laid down.
> Colour additives and their lakes which are listed for directuse in foods in parts 73, 74, 81 and 82 of chapter 1 of 21 CFR 178 may also be used as colourants for food-contact polymers.
The current (1st April 2013) version of 21 CRF § 178.3297 can be downloaded here.
Chapter 21 of the Code of Federal Regulations is updated every year on 1st April. As the document mentioned above was located using the ''most recent' year search, it appears that this section was not updated in 2014.