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Can You Microwave Styrofoam Takeout Boxes?

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Microwaves are a great tool to reheat leftover food in a matter of minutes, and they are mainly used for heating and preparing food. For health reasons, you should be cautious about the type of containers used while warming food with a microwave, especially styrofoam take out boxes. 

Can you microwave Styrofoam take out boxes? Styrofoam take out boxes generally have a low melting point that may start melting before the food is reheated when heated in the microwave. 

Styrofoam containers are designed to insulate hot food while transporting, but not such a great option when it comes to cooking or reheating. However, there are microwave-safe Styrofoam boxes that can be easily identified with a symbol on the bottom of the disposable container.

Always check for the microwave-safe label to ensure the styrofoam boxes are safe for microwave use. And even if it is safe to use in microwave, use a small amount of food, nuke on the reheating and do not overheat the styrofoam container. 

Styrofoam boxes are relatively cheap and good insulators that will help keep beverages and food warm throughout the travel period. Unfortunately, they contain Styrene, a plastic compound that is said to cause cancers in human and animals. 

In this article, we will investigate if Styrofoam is toxic and whether it is safe to microwave Styrofoam with food. Answered below are frequently asked questions about recommended timing and temperature for best result to microwave Styrofoam take out boxes so you can enjoy your leftovers next time you need a meal.

Even though there is minimal data to confirm this, melted plastic in food does seem like an apparent cause for concern and you don’t want to risk your health. Amongst the plastics that are unsafe for microwave use, the side effects of Styrofoam are way worse than the benefit of convenience.

Is Styrofoam Toxic to Humans?

Styrofoam contains Styrene, a polymer compound that is harmful to humans and the environment. When Styrofoam melts, it releases toxins that are absorbed into our tissues and bloodstream. 

Suppose low quantities of styrene are repeatedly taken into our bodies for an extended period. The toxins can buildup over time leading to side effects such as nervousness, fatigue, hematological and carcinogenic consequences. 

Further, the component affects the central nervous system leading to depression and headache. Also, Styrene can distort the functioning of the kidney and blood. 

Styrene’s toxicity to humans manifest in the neurotoxin that destroys the peripheral and nervous systems. Women who are exposed to styrene are likely to experience irregular menstrual cycles that may interfere with the reproductive system.

Is It Safe to Microwave Food in Styrofoam?

Styrofoam contains organic and inorganic components added to make it clear and flexible. These components negatively affect human hormones, hence the large push for bpa free plastic over 10 years ago..

When you place food in Styrofoam containers and heat it in a microwave, the container potentially melts and leaches toxins into the food. It is also very possible that the toxins leak chemicals by just putting hot food in a Styrofoam take outbox. 

Hot fatty and sugary foods are more likely to be contaminated than other foods because the heat point of both are significantly higher than the boiling point of water. Therefore, they can be hotter and take much longer to fully cool down.

Only use containers with a microwave-safe symbol to be sure of your safety. 

On the contrary, some Styrofoam containers have a safe label on the bottom. If this is the case, then follow the procedure you use to warm food in the microwave using other containers.

For best results, transfer the food to microwave safe containers that are preferably made of glass or ceramic. This will provide the safest option with less risk to you and the food.

Is It Safe to Reheat Food in Styrofoam?

Styrofoam has a wide range of products, and there is no clear information on which products are safe or not. One item might be safe, while another product of similar nature might not be, so the physical appearance of the packaging can’t help you decide its category. 

Avoid reheating your food repeatedly. The disposable styrofoam containers are not designed for reuse, so one pass through the microwave is risky enough, let alone multiple uses of the same receptacle.

Unfortunately, we can only tell the product’s safety by checking the safe label or trying it out. It is important to note that Styrofoam has a relatively low melting point, no matter whether it is considered safe or not. 

The microwave appliance heats food unevenly, causing some specific areas to exceed the melting point of the container. When the container is above the melting point, small quantities of styrene leach in your food; consuming such polymer compounds may lead to health concerns.

How Long Can You Microwave Styrofoam?

Pure styrene melts at 350 degrees Fahrenheit, 175 degrees Celsius, while polystyrene can go up to 435 degrees Fahrenheit, 224 degrees Celsius. Avoid cooking anything using Styrofoam at these temperatures as most plastics are likely to melt in these temperature ranges. 

If you microwave Styrofoam for too long, it will eventually melt any one of the polymers components like acetone. 

For instance, when boiling water using a styrofoam cup. The temperature of the water is below the recorded melting point of polystyrene, but you could be getting polystyrene into the liquid as your cup above the fill line begins to melt.

If the box does not have a safe label for microwave use, don’t put styrofoam in the microwave. Don’t even try it, even if it’s only 30 seconds; refrain from it all together. 

If you must microwave coffee in a styrofoam cup, then don’t heat it at all and instead use a cup that is microwave-safe to reheat the beverage.

Tips to Microwave Styrofoam Take Out Boxes

Apply the following tips, especially if you are cautious about using Styrofoam to microwave food.

  • Select a safe microwaveable container. In case you are using Styrofoam take out box, ensure it has a microwave secure icon on the bottom of the packaging. 
  • Take out trays are designed for single use. Please read the instructions on the package and don’t use it twice to heat food in the microwave.
  • Don’t allow plastic wrap to be in contact with your food as it might melt. Use other safe alternatives such as paper towels, kitchen paper, wax paper or another container that will cover your Styrofoam bowl or plate.
  • Ensure there are no cracks or scratches. Avoid using Styrofoam containers with cracks and scratches in the surface. Consider disposing of them immediately since they have a high possibility of leaching harmful toxins into your food and drinks when holding hot food.
  • Open the Styrofoam box before heating it. Venting will help prevent steam formation in the box, since steam has 7 times the heat transfer rate of direct heat causing more concern for melting risk.
  • Stir your food often. To avoid heating your food above the Styrofoam melting point, microwave for a short time, then stir. Stirring food often will make it heat up more evenly which is much safer in the end. Consider heating half of your food first, so you only have to turn it for two rounds.
  • Be careful while removing the box. Remove the container from the microwave carefully as it will be much hotter than you anticipate. Consider using gloves when removing the container after heating; this will save you from hand burns.
Can you microwave styrofoam take out boxes

Styrofoam Take Out Boxes in Microwave: Conclusion

The safety of containers without a microwave-safe label is not guaranteed. Even if it is properly labeled, it is still a type of plastic and there are many reasons to be hesitant about microwaving plastic.

The reason being, Styrofoam comprises a compound known as styrene, which is said to cause cancer. However, food boxes with the safe label are likely not to cause such risks since they are already tested with manufacturer recommendations for safe use.

Styrofoam is made out of plastic, so even though it is microwave-safe, be cautious when reheating food. 

Start with small amount of food with low power setting using short bursts of time. In addition, frequently stir to get even out the heat throughout the food.

The temperature plays important part when microwaving Styrofoam. Ensure that the temperature does not exceed 350°F or 175° C, this is where polystyrene starts melting. Avoid reheating or cooking in the Styrofoam over this temperature. 

Furthermore, when microwaved for too long even thought it hasn’t reached this temperature, it will eventually melt the acetone

Do no reuse or heat the Styrofoam take out box more than once. It is designed for single use only and it is not capable to adjust the temperature change. 

In case you end up microwaving Styrofoam, ensure that there is no scratches or cracks around the inside of the container. This leads to a high potential of leaked chemicals into your food.

After reaching desired temperature, cautiously remove the box with gloves and slowly open the lid to avoid any burst of steam that escapes to avoid burning your hands and face. 

If you are not comfortable using Styrofoam, consider transferring your food to a microwave-safe container or plate before heating. Additional options includes ceramic, glass and Pyrex plates. 

Alternatively, avoid the microwave and use the pan to heat your food. Your health should come first, not always the convenience.  

To consume safe food and remain in good health, don’t use every type of container to warm food in your microwave. If you feel uncomfortable microwaving plastics; the same should apply for Styrofoam. Avoid it to be on the safer side.

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