Can You Put Styrofoam in the Oven? (Important Facts!)

After a tiring day or if you’re feeling lazy, tossing leftovers from the restaurant in the oven may seem the best thing to do.

An oven can be a godsend on days when you don’t feel like putting much effort into heating your food. However, not all takeaway containers are oven safe and should be used in the oven.

Many times, grocery store food or restaurant takeout arrives in Styrofoam containers, which raises the question, can you put Styrofoam in the oven?

Let’s discuss in detail if it is safe to put Styrofoam in the oven.


What is Styrofoam?

Before discussing if you can put Styrofoam in the oven, it is essential to understand what Styrofoam is since many people confuse it with other materials. Styrofoam is mainly composed of white or light blue polystyrene foam, a form of plastic (1).

It is a lightweight material that is commonly used in the production of packaging or takeaway containers, disposable plates, or egg cartons.


Is it okay to Put Styrofoam in the Oven?

Many individuals may believe putting styrofoam products in the oven is okay because most are microwave-safe. But, it is crucial to understand that you should never put Styrofoam in the oven.

Expanded polystyrene, the primary component of most Styrofoam products, is a substance that dissolves under heat.

At 100°C, Styrofoam will start to soften; once it reaches 240°, it will completely melt. Therefore, while storing leftovers in Styrofoam in the refrigerator is safe, it is never a good idea to heat up leftovers in the oven.

Here are a few additional dangers associated with heating Styrofoam in the oven and the risk of the container melting. Read about some of the dangers below.


Melted Styrofoam Could Contaminate Your Food

Did you know that according to studies, Styrofoam includes harmful compounds, including styrene, which is dangerous to humans since it is considered carcinogenic (2)?

The polystyrene substance that makes up Styrofoam, when heated in the oven, has the potential to produce toxic compounds that might contaminate your food.

According to NIST, polystyrene starts to break down when the temperature reaches 200 °C (3,4).

Once it reaches this temperature, it emits microscopic amounts of chemicals. However, if the temperature reaches 224 °C., the polystyrene begins to dissolve and produce an overwhelming amount of toxic substances, which can seriously harm your health.


Styrofoam Can Release Hazardous Fumes When Heated

When Styrofoam reaches a high temperature in the oven and begins to burn, it can emit hazardous fumes that can damage one’s health if inhaled.

The smoke may contaminate the air in your home, making it dangerous for you and your children.

Important note! Do not be alarmed if you heated Styrofoam in the oven before reading this. Heating Styrofoam in the oven once or twice may not be enough to affect health significantly.


Styrofoam Can Become a Fire Hazard

Styrofoam is a flammable substance. This implies that it may catch on fire if exposed to high temperatures. Many manufacturers add compounds to Styrofoam to reduce fire hazards and ensure the safety of their clients.

However, it is advisable to be cautious to ensure your home does not catch fire.

With all of these considerations in mind, it is preferable to plate your dish before placing it in the oven. The dangers of heating Styrofoam containers make it preferable to go through minimal effort than to put your life in danger.


Why Is Styrofoam Used To Package Food?

Now that you know Styrofoam is not oven safe, you may wonder why stores and restaurants favor Styrofoam wrapping for their food.

Here are some of the reasons:

  • Insulation: Keeping food at warm temperatures for restaurants is essential to ensure customers are satisfied and do not receive cold food. The insulating properties of Styrofoam help maintain the temperature of the food inside
  • Inexpensive: The main reason restaurants and supermarkets prefer packaging food items in Styrofoam is that it is a cheap alternative compared to other packaging materials, which helps them cut costs
  • Lightweight: Since Styrofoam is a lightweight material, it makes it easier for delivery personnel to carry around bulk orders


Styrofoam Alternatives

Now that you know not to put Styrofoam in the oven, here are some alternative materials you can use to heat your food safely:

  • Flat pans/cookie sheets: Cookie sheets are large and allow you to efficiently distribute your food while safely heating it in the oven. Yet, it depends on the food you are heating, as not all foods heat well on cookie sheets
  • Oven-safe containers: Oven-safe containers are an excellent substitute for Styrofoam containers. We put glass oven-safe containers on the top out of ceramics and steels/metals since when you cook or store food, you can quickly put a lid on them and put them in the fridge, and when you need to heat the food, take them out of the refrigerator and put them in the oven. This simplifies heating because you don’t have to bother placing food in a safe container and getting numerous dishes dirty only to warm food. If you don’t have glass oven-safe containers, metals and ceramics work just as well; make sure they’re oven safe before purchasing them
  • Aluminum foil: Besides helping the food heat quickly, aluminum foil helps easy cleaning and prevents your pans or dishes from getting dirty. All you have to do is evenly layer aluminum foil on your pans, and once the food heats up, carefully remove the aluminum foil and dispose of it


What Is The Safest Way To Heat Up Your Food In The Oven?

If you want to ensure you are following the safest and best possible method of heating food in the oven, here is how you can do that:

  • If you have ordered takeout, do not heat food in the packaging that it arrives in
  • Always take food out on an oven-safe plate
  • Double-check to ensure you do not leave any metal utensils in your container before turning on the oven
  • Make sure to put an oven or microwave-safe lid on your food before turning on the oven
  • Since cold areas of your food containers may have bacteria, rotate the food container or stir the food once or twice to eliminate the bacteria and ensure all parts of the container get heated equally


Can You Microwave Food in Styrofoam Containers?

Many people automatically assume that if you should not put Styrofoam in the oven, you shouldn’t put it in the microwave either. However, you should be aware that if the Styrofoam is microwave safe, you can place it in the microwave.

Most Styrofoam materials in the market that carry food items are microwave safe.

If you are doubtful, you can always call the manufacturer or ask the restaurant where you received the food. Moreover, knowing how to heat food in a Styrofoam container in a microwave is also essential.

It is recommended to heat Styrofoam containers in the microwave with a glass of water inside. The glass of water maintains moisture in the microwave and helps keep the Styrofoam from becoming brittle or dry.

Important tip! Always wear microwave or oven mitts when taking Styrofoam containers out of the microwave or oven to ensure you don’t burn your hands.


What Other Purposes Can I Use Styrofoam Containers?

Let’s say you have a bulk of Styrofoam containers you bought to reheat food in the oven.

Now that you know they are not safe to put in the oven, what do you use them for? There are many ways you can use Styrofoam containers.

Here are a few ways you can use Styrofoam containers:

  • Package food to take it to the office
  • Store food in the fridge
  • Serve food if you are too lazy to wash the dishes afterward
  • Carry hot or cold beverages


In Conclusion

We hope that the following information helped clear any queries and doubts about can you put Styrofoam in the oven.

Always use oven-safe materials to heat your food since heating food in materials like Styrofoam can become a health hazard and a fire risk.

Instead of Styrofoam, you can use other microwave-safe containers such as cookie pans or glass/ ceramic containers to heat your food safely.

Check also:



1. What Degree Of Heat Is Safe To Use On Styrofoam?

Styrofoam is not capable of surviving extreme heat. At 100 degrees Celsius, this substance will begin to liquefy. Styrofoam containers shouldn’t be used in the oven since they are composed of polystyrene foam, which quickly decomposes when exposed to high temperatures.


2. Can I Eat Food After Heating It In A Microwave?

Polystyrene packaging and food containers have been approved by the (FDA) for use with both cold and hot food products (5).

Also, before putting Styrofoam in the microwave, always check for a little microwave sign featuring wavy lines to tell if the polystyrene container is safe to put in the microwave.