Inks are used on many packaging materials including plastics and paper to convey consumer information and for brand marketing purposes. Materials including glass and plastic may also be dyed. Inks and dyes are typically comprised of colorants, binders, solvents, and additives such as phthalate and non-phthalate plasticizers [1].

Inks and dyes can migrate (through direct and/or offset migration) onto food. The addition of printing inks to recyclable paperboard results in the presence of chemicals such as high-concern phthalate plasticizers in recycled materials [2].

Thousands of different compounds are used in printing inks, and many have little to no regulations concerning their use in food contact applications [3]. Switzerland has led in the effort to regulate inks and dyes, and issued a positive list for inks and adhesives in 2010 that lists more than 5000 substances [4]; however, only a few have gone through robust toxicology evaluations [3, 5].

Preferred printing inks will have some or all of the following characteristics:

• They avoid low molecular weight compounds (<1000 Da) in inks, as those migrate more easily
• They do not contain phthalates, or solvents of concern such as toluene
• Additives are evaluated for food contact safety