Researcher Birgit Geueke compiled an extensive dossier on silicone and conducted a review of silicone as a food contact material in the journal Food Packaging Forum. (For an interview with Dr. Gueke on silicone, see here.)
Substances that may migrate from silicone-based materials into food include oligomers, additives, catalysts, and breakdown and reaction products. In the last ten years, several scientific studies investigated chemical migration from silicones into food.
For repeated-use articles, the migration of siloxane oligomers sometimes exceeded the legal limits especially during the first cycles of use. A high fat content of the food was described to increase migration. Substances related to printing inks (e.g. benzophenone and diisopropyl naphathalene), phthalates and aldehydes were reported to migrate from silicone baby bottles into milk.
Some silicone compounds act as a weak estrogen and were found to cause impaired fertility in rats and an increase in uterine tumors
Many household utensils which are in direct food contact, e.g. baking molds, spoons, spatula, containers, gaskets and ice cube trays, are composed of silicone rubber. Baby soothers and feeding teats are also commonly made of silicone rubber. Silicone resins are commonly used as anti-stick coatings on kitchen utensils and in food processing factories.