Can silicone bakeware release siloxanes into air or food?
Use caution. Silicone bakeware can release volatile methylsiloxanes during baking, especially when new or heated. Wash it first, follow the maker's temperature limit, and choose porcelain or glass for hot, oily foods when you can.
What's actually in it
Silicone bakeware is made from silicone polymers. Some pieces also contain small leftover siloxanes. These include cyclic volatile methylsiloxanes, such as D4, D5, D6, D7, D8, and larger related siloxanes.
Heat matters. New silicone molds can release more siloxanes during baking. The amount drops after the first uses, but it is still smart to wash new silicone well and stay below the maker's temperature limit.
What the research says
A 2019 study in Environ Int tested 14 new silicone baking molds and 3 metal molds during oven baking. The researchers found volatile methylsiloxanes in indoor air after baking and measured siloxanes in cake, with higher levels at the cake edge than the center.
The study also found that using silicone molds more than once reduced airborne siloxane levels. The authors said silicone molds should be precleaned and used within the maker's temperature directions.
What to do at home
You do not need to throw out every silicone tool. For baking, start with easy swaps. Use porcelain ramekins or glass dishes for small baked foods. If you use silicone, wash it first, avoid damaged pieces, do not heat it empty, and follow the temperature limit on the label.
The research at a glance
| Study | Journal | Year |
|---|---|---|
| Siloxane in baking moulds, emission to indoor air and migration to food during baking with an electric oven. | Environ Int | 2019 |