Can styrofoam go in the oven? (+3 alternatives)

In this article, we will answer the question “Can styrofoam go in the oven?”, and what is styrofoam?

Can styrofoam go in the oven?

No, you cannot put styrofoam in the oven. The polystyrene beads require only a temperature of 100℃ to soften. This is the boiling temperature of the water. The average heating temperature for food in the oven is 320 to 350 °F. 

If you are trying to heat your food below 212°F in the oven, you might as well not use the oven anyway. Moreover, eating hot food from styrofoam containers is unsafe. 

What happens when you put styrofoam in the oven?

When styrofoam is subjected to the high temperatures of the oven, It starts to melt or decompose. The result is an oily, sticky, and melted liquid. The oil comes from the styrene in the styrofoam. 

Safe materials for reheating food in the oven

Metals: metals like stainless steel and cast iron is considered safe for reheating food in the oven. It is because metals have a high-temperature threshold.

Glass: tempered glass that is safe for use in the oven is a good alternative to styrofoam. The plus point is that glass containers are multipurpose. 

You can serve the food in the same glass container that you used for reheating. Make sure the glass containers do not have a wooden handle or plastic details.

Ceramics: as long as the ceramic dishes or plates are labeled ‘oven-safe, you can safely use them to reheat food in the oven.

What is styrofoam?

Originally, styrofoam is an extruded polystyrene foam that is commonly employed in the building industry. In the US and Canada, styrofoam refers to a type of expanded polystyrene which is used shaped through molds, into disposable plates, cups, containers, etc. Let’s get into what is extruded and expanded polystyrene.

In the making of extruded polystyrene, polystyrene is melted along with a variety of ingredients. For expanded polystyrene insulation, the first step involves filling the molds with the polystyrene beads. 

These beads are melted and expanded by bombarding them with steam or heat. Polystrene, with monomer styrene, is a common plastic material. 

When polystyrene is converted into foam-like stuff, It becomes light due to the incorporation of about 95% air in its composition. The air also provides excellent cushioning properties. 

What is styrofoam used for?

Styrofoam is used to make food containers. It is a very convenient and light packaging to contain food. Due to the insulation properties, It keeps the food warm or cold.

What temperature can styrofoam withstand?

The polystyrene beads that expand into styrofoam melt at 464 °F (240 °C). However, the beads are already softened when the temperature is at 212°F (100°C).

What If you accidentally burn styrofoam?

Burning the styrofoam container and/or eating food off a burnt styrofoam container would neither hurt the environment nor your health. 

But this is not how It works. When burnt, styrofoam releases dangerous gas and chemicals that are toxic to the environment and your health. Prolonged exposure causes lung damage.

Banning of polystyrene 

Polystyrene contains hydrofluorocarbons (HFCs) which have been linked to adverse impacts on the ozone layer. 

Due to the unpleasant effects of polystyrene on the air quality and the negatively progressing climate change, styrofoam has been banned in the US. 

Studies have shown an association of styrene (monomer of styrofoam) with cancers in animals and humans.

What happens when you microwave food in styrofoam?

Regular styrofoam containers are not supposed to be used in the microwave. The temperature threshold of styrofoam is very low. 

When placed in the microwave It will release toxic gas and chemicals. However, microwave-safe styrofoam has also been developed. As long as you have microwave-safe styrofoam, you can go ahead with reheating food in the microwave.

Microwaving food safely

Follow the steps below before putting styrofoam in the microwave to ensure safety.

  • Transfer your food to a microwave-safe plate or container.
  • Make sure the food is leveled in the container so that It is heated evenly in the microwave.
  • When microwaving very cold or frozen food in the microwave, you need to stir the food or change the position of the container after regular intervals. This ensures even heating and eliminates the possibility of cold spots. These cold spots can harbor harmful bacteria.
  • Instead of the microwave, you can also reheat your food in the oven or on the stovetop. For this, transfer the food into a pot or pan.
  • Do not use any polystyrene or plastic container in the microwave that has cracks or scratches. These can release harmful chemicals into your food.
  • Wear mittens before removing the hot container from the microwave. 


In this article, we answered the question “Can styrofoam go in the oven?”, and what is styrofoam?