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Can you microwave Styrofoam?

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Microwaves are among the most quickest, easiest and most effective kitchen appliances in the tech-world. For decades now, people have been utilizing microwaves to heat food in styrofoam, thus easing their work around the kitchen.

When utilizing a microwave, there are several specific kinds of materials that you should not use. However, not everyone knows the best kinds of containers to use when microwaving their food and drinks. 

To give you a straightforward answer, Styrofoam is not completely microwave safe. Safe microwave usage with Styrofoam depends on factors such as microwave safe grade material, medium power level and heat for 30 seconds at a time.

This article leads you to the safety concern about Styrofoam usage, recommended types of Styrofoam, and tips to microwave Styrofoam safely,.

What does a Styrofoam mean?

Styrofoam is only a brand title for a polystyrene foam that was originally designed for construction insulation. The material is synonymous with plastic, and therefore found its way into the food service industry.

Because it is cheap, lightweight and effective, Styrofoam has several purposes including food packaging, transportation and storage. Most people utilize Styrofoam as plates, beverage cups, or takeout foods.

Styrofoam food service containers come in different forms and feature multiple usages:

The popularity and wide range usage of Styrofoam are due to its insulating capabilities, cheapness and lightweight design. Recently, most US cities have banned people from using Styrofoam because of the effects it poses on the environment and peoples’ health.

Styrofoam decomposes at a slower rate, and when carelessly disposed of, animals can consume which can be extremely hazardous. Also, Styrofoam has a toxic compound known as styrene, which has been directly correlated to causing cancer in human beings and animals.

Materials used to make Styrofoam (EPS) are not recyclable, which further contributes to its banning and unaccepting.

Is it safe to microwave Styrofoam?

With the above negative effects of Styrofoam, many individuals are still on the dilemma of using them. It is hard to do away with Styrofoam utilization as they remain the most reliable and cost-effective way of packaging takeout and serving food on the go.

The good news is you can use polystyrene containers to microwave food and drinks only if they labeled as microwave-safe. If you don’t see any symbol indicating that you can use it, just don’t use it. 

Identifying the symbol is easy, the logo is wavy lines looking like a microwave. If the logo is not present, then a label stating the words “microwave-safe” should be present in its place, however the symbols might vary depending on the manufacturer. 

It is crucial to ensure that they are not fake. There are numbers for types of polystyrenes that are safe to use. If you keen enough, most plastics have a recycling number inside a triangle in the recycling symbol. 

The triangle is usually located below the plastic, and it has arrows. The number inside that triangle indicates the plastic-type and if its microwave-safe or not.

The microwave-safe recycling code is number 5, and the unsafe are 3, 6, and 7. Sometimes numbers 1, 2, and 4 can be safe, but the best bet remains to be 5.

Therefore, it is crucial that you don’t utilize PVCs with numbers 3, 6, and 7 while microwaving food. Unless the number 6 styrofoam is labeled as microwave safe, then these forms of plastics are highly carcinogenic and have deadly toxins like Bisphenol. 

Be very cautious when utilizing the partially-safe plastics, that is numbers 1, 2, and 4.

In most cases, partially-safe PVCs are commonly used for storing yogurts, sour cream and margarine. However, some are chemically reinforced to withstand heat, making them microwave safe but not for long durations or high temperatures.

To be safe, you should go for type 5 polystyrene. It is strong and resilient to heat to a greater degree. Even after using this type of polystyrene on a microwave, it will remain cold, indicating how strong and effective it is to use when microwaving foodstuff.

Can you microwave styrofoam?

Will microwaving Styrofoam kill you?

Microwaving Styrofoam may not kill you, but it can impose a variety of health issues and concerns to be aware of. That’s because — Styrofoam is a synthetic material and it contains a variety of toxin compounds that may break down and mix into your food when exposed to high heat of the electromagnetic radiation process.

Please note that there are two types of Styrofoam found in the market, such as traditional Styrofoam and microwave-safe Styrofoam. 

Traditional Styrofoam is safe for normal usage i.e. you can use it as a storage container for food to transport from one place to another. However, the composition of the traditional Styrofoam containers will melt and break down when it is exposed to high temperatures.

Especially, inside a microwave, the electromagnetic radiation process happens that leads to the formation of extremely high temperatures. Under such high temperatures, traditional Styrofoam compounds may be melted and get leeched into your food. 

When these toxic materials get mixed in your food, it may cause a variety of health concerns that should be avoided. For example, it can affect your reproductive system since these toxic and synthetic materials are not good for your health. 

Another study has shown that traditional Styrofoam contains a chemical named as styrene. This chemical can cause two critical diseases, such as leukemia and lymphomas.

In the previous sections, you have already revealed the hazards of microwaving traditional Styrofoam containers. Rest assured that this type of material is not suitable for high temperatures,especially inside a microwave.

But, do not worry anymore as there is a safer and better option for you, for example, microwave-safe Styrofoam. Compared to the traditional variant, microwave-safe Styrofoam is made with safer, better, and less hazardous chemical compounds.

Microwave safe Styrofoam is designed in such a way that it will not melt or break down at high temperatures. Even if you expose a microwave-safe Styrofoam containers to extremely high temperatures inside a microwave, there won’t be any problem as such! 

The composition of microwave-safe Styrofoam containers will stay intact and stable at higher temperatures. Plus, they also come with the microwave-safe labeling that is approved by the FDA guidelines.

Tips to Safely Microwave Styrofoam

Just because some kinds of plastics are unsafe to use in the microwave doesn’t imply that you’ll never use your microwave again, you will still need it for many cooking conveniences. But how can you utilize it without causing any health threats to your life? 

Below are several microwave tips you can employ to safely heat foods and drinks:

  • Use containers with safe symbols. For any heating process, it is important to always check if the container you are using is microwave-safe or not. Check the recycling number and microwave safe symbols on the bottom to see if it is recommendable and certified for use. Be wary of fraudulent and deceitful manufacturers. Some low quality producers don’t ensure that they are using the required materials and procedures to make safe containers.
  • Have options. If you can’t access a microwave safe Styrofoam that is properly vetted to use, you can opt for other options like glass, Pyrex, or ceramic containers. Transfer your food or drink into the containers mentioned above before microwaving food for a much safer heating option.
  • Check to see if the microwave Styrofoam is scratched or cracked, While microwaving food, it is important to use containers that are in good shape. Ensure that they don’t have any cracks, pits or abrasions that can facilitate any form of leaking during the heating process. Cracked microwave Styrofoam can leach hazardous chemicals into your food, which may be harmful to you. Dispose of old and cracked containers to avoid any health inconveniences. Also, don’t accept damaged or scratched containers when purchasing Styrofoam to use in your microwave, storage or transportation.
  • Before you start the heating process, vent the container. It’s advisable to open the heating container to avoid pressure building on the inside. Pressure accumulating inside the Styrofoam can cause the food inside it to explode. Furthermore, steam trapped inside the container can form condensation of the top of the lid, that could drip potentially hazardous chemicals into your food.
  • Use safe methods to remove the heating container inside your microwave. It’s unsafe to use bare hands to take out the container. Mittens or kitchen gloves make it easier to remove a hot container after you are done heating the food. Utilizing bare hands exposes you to the risk of burning.
  • Utilize a cooker or oven. When you have a microwave, it’s compulsory to use it every time you want to heat food. Sometimes, you can decide to utilize your stovetop or oven for better results. Put the food you want to warm in a pan and heat it using your stove.
  • Be aware of containers and foods you are not supposed to utilize. Packages for takeaway foods are meant for onetime usage and are not to be recycled, styrofoam containers fall into this category. Also, don’t heat food in your microwave using yogurt, cheese, or margarine packages as they aren’t certified to be microwave safe. Other packages you shouldn’t microwave are grocery plastic bags and certain kinds of foods like hot pepper, eggs that are still in their shells, whole fruits, and frozen meat.
  • Use 30 second increments. When heating food in Styrofoam containers, it is recommended to nuke for 30 seconds at a time on a medium power level to minimize the potential risks.

Microwaving Styrofoam: Final Thoughts

Utilizing polystyrene containers when microwaving food is not as safe as many people believe. However, the dangerous thing is using those that aren’t certified as microwave-safe.

Always ensure to utilize microwave-safe polystyrene products when heating food. Look on the bottom of the container to quickly verify whether or not the styrofoam is safe to use in the microwave.

Look for a microwave safe symbol or label that guarantees the product is microwave safe. That being said, there are certain precautions that should be followed when heating food in the microwave.

When heating food in microwave safe styrofoam, use medium power level and heat for 30 seconds at a time. Short durations and lower level of heat will reduce the risk of exposure to harmful chemicals present in the polystyrene foam.

In case of any doubt, transfer food to one of the best microwave-safe containers, for example ceramics and glass, before starting to heat.