Can You Microwave Plastic? [Answered]

Most microwave owners are privy to the information that microwaves and plastics are a terrible match. However, things happen, and you find yourself heating your Tupperware-packed lunch you have brought to work in an office microwave.

Since most food containers are made of plastic, you are likely to find yourself warming yesternight’s leftovers in a plastic container. But, can you microwave plastic?

While it’s possible to microwave plastic, you need to be careful about the type of plastic you are using. Look out for a microwave-safe symbol on the plastic container before microwaving it.

The symbol includes three wavy lines that symbolize the container can be microwaved without melting or emitting harmful chemicals. 

Containers without the microwave-safe symbol may not necessarily be unsafe for the microwave. However, the lack of the sign means they haven’t gone through the relevant tests required to guarantee microwave safety. So, do you have to toss all your plastic storage containers without the microwave-safe symbol? Read on to learn more.

Types of Plastics

Can You Microwave Plastic?Plastics are materials made from long chains of polymers containing thousands of repeating monomers. Besides the polymers, there are other substances that are added to stabilize these plastic containers. The common stabilizers in plastic are: 

  • Bisphenol A (BPA) makes transparent plastics hard. These plastics include water bottles and CDs.
  • Phthalates make plastics stronger and more flexible such as rubber duckies.

Most plastics have a recycling triangle at the bottom with an identification code that ranges from 1 to 7. These numbers reveal the type of plastic the container is made from. Here are the seven types of plastics;

  1. Polyethylene terephthalate (PET or PETE): Plastics used for packing drinks like sodas, cooking oil containers, and mayonnaise jars. 
  2. High-density polyethylene (HDPE): They are ideal for making hand soap and detergents containers, milk jugs, protein powder tubs, and butter containers.
  3. Polyvinyl chloride (PVC): These are common for making synthetic leather products, electrical wiring insulators, plumbing materials, medical tubing, and shower curtains. 
  4. Low-density polyethylene (LDPE): They are ideal for making squeeze bottles, plastic bags, and food packaging.
  5. Polypropylene (PP): They make bottle caps, baby bottles, food storage containers, yogurt containers, single-serve coffee capsules, and shaker bottles.
  6. Polystyrene or Styrofoam (PS): These are for disposable food containers, plates, disposable cups, and packing peanuts.
  7. Others: They include polycarbonate, acrylic, acrylonitrile butadiene, polylactide, styrene, fiberglass, and nylon.

There are different plastics for diverse applications.

What’s the Risk of Microwaving Plastics?

Can You Microwave Plastic?As long as the plastics have approval from FDA to be used in the microwave, there is little to no risk to microwaving them. Microwave-safe plastics are designed to resist softening when heated in the microwave. Such plastic containers don’t contain BPA, phthalates, or other harmful chemicals. 

However, there are particular plastics like polycarbonates that are not FDA-approved for use in the microwave. And the main concern with microwaving such containers is:

  • Heating up food in a microwave using unsafe plastic containers can cause the leaching of BPA and other harmful chemicals like phthalates into the food at high temperatures. Research has shown that both contaminants have potentially dangerous effects on human health.
  • Some studies show that BPA can lead to obesity, diabetes, infertility, and a disruption of your body’s hormones. The U.S. Food and Drug Administration (FDA) recommends limiting exposure to BPA for infants and children as much as possible, given potential health risks.
  • Further reports suggest that people who consume foods with high levels of phthalates are at high risk of suffering cardiovascular diseases, leading to death.

Foods with high content of fats like cream and butter absorb high BPA and phthalates when heated.

How to Avoid BPA and Phthalates in Plastic

Can You Microwave Plastic?The best way to avoid BPA and phthalates in your food is to avoid microwaving plastic containers that contain the chemicals. Instead, use microwave food containers made from glass, metal, and other materials that don’t emit chemicals when exposed to high temperatures.

Plastic containers with the recycling symbol “3” and “7” have high levels of phthalates and BPA, respectively, thus avoiding them where possible. If you have to microwave your plastic container, ensure it has the microwave-safe symbol.

Other preventive measures are:

  • Avoid placing hot foods and drinks in plastic containers.
  • Avoid abrasive bruising of plastic food containers using scrabbing materials like steel wool. Thye can scratch the container and expose you to unwanted chemicals. 
  • Avoid using plastic containers for an extended period.
  • Do not expose your plastic containers to the dishwasher frequently. 
  • Quickly replace any plastic container that shows any signs of wearing off with containers made from glass or BPA-free plastic containers.

Alternatives to Microwaving Food in Plastic Wrap

There are many safe alternatives to microwaving food in plastic containers. Some of these alternatives include:

  • Glass: Glass is an excellent material for microwaving food. It doesn’t leach chemicals like BPA and phthalates into your food and is easy to clean.
  • Ceramic: Ceramic is another safe material for microwaving food. Like glass, it doesn’t leach chemicals into your food and is easy to clean.
  • Stainless steel: Stainless steel is also a safe material for microwaving food. It doesn’t leach chemicals into your food, is easy to clean, and doesn’t rust.
  • Paper: Microwaving food in the paper is a great way to avoid leaching chemicals into your food. Just make sure the paper is microwave-safe.
  • Food wrap: Food wrap made from silicone, plastic, or wax is a great way to wrap your food before microwaving it. Just make sure the wrap is microwave-safe.

Recycling Tips for Plastics

When recycling plastics, here are some things you should keep in mind:

  • Look out for the recycling sign on the bottom of the container. This will tell you what type of plastic the container is made from. 
  • You can recycle different types of plastics. Check with your local recycling center to find out how to recycle every kind of plastic container in your possession.
  • Not all plastics can be recycled. The most common types of plastics that you can recycle are polyethylene terephthalate (PET), high-density polyethylene (HDPE), and polypropylene (PP). In contrast, polycarbonates plastics will not be accepted by recycling centers.
  • If a recycling center doesn’t accept a specific type of plastic, it may end up in a landfill. 


How to Properly Dispose of Plastic

If a recycling center doesn’t accept a particular type of plastic, plan to dispose it. When disposing of plastics, there are some things you should keep in mind:

  1. Clean the plastic before disposing of it. This will help reduce the number of bacteria that can grow on it and reduce contaminations at the disposal center.
  2. If possible, crush the plastic before disposing of it. This will take up less space in the landfill and make it easier for the disposal center to manage.
  3. Ensure the plastic is properly disposed of in a designated area at the landfill. Improperly disposing of plastics leads to environmental pollution and can be harmful to animals.
  4. Recycle any recyclable plastic. Doing so will help reduce the amount of plastic in landfills.
  5. When in doubt, consult your local recycling center or municipality about the proper disposal of plastics.

How to Properly Store Plastic

If you have plastic containers that you are not using and want to store them, there are some things you should keep in mind:

  1. Store plastics in a cool, dry place. This move will help prevent the growth of bacteria and fungi on the plastic.
  2. Do not expose plastics to direct sunlight. Direct sunlight can cause the plastic to degrade and leach chemicals into your open food or water.
  3. Store plastics away from heat sources. This action will prevent the plastic from melting or warping.
  4. Store the plastic containers in a safe place where they will not be damaged or eaten by animals.
  5. Store the plastic in a clean place. This will help reduce the number of contaminants on the plastic.

The Benefits of Microwaving Food in Plastic Containers

Even though not all plastic containers are microwavable, some are perfect for microwaving. And here are some benefits of microwaving food in plastic containers:

  • It is a safe way to heat food. Microwavable plastics don’t leach chemicals into your food. So, you can be sure that the food you are eating is not contaminated.
  • It is a convenient way to reheat leftovers. Primarily, leftovers are stored in the fridge using plastic containers. Provided the containers are BPA and phthalates free, reheating them in the microwave is a quick and easy way to eat them.
  • The plastic container will keep the food warm. When you microwave food in a microwavable container, the heat is trapped in and keeps the food warm. This is especially helpful when you are reheating large quantities of food.

Faqs About Microwaving Plastics

Here are  some FAQs about microwaving food in plastic containers:

Are all plastics safe to microwave?

No, not all plastics are safe to microwave. You can only microwave plastics that bear the microwavable label.

How long can you microwave plastic?

There is no definite answer to this question as it depends on the type of plastic the container is made from. However, most plastics are safe to microwave for a few minutes. Always consult the manufacturer’s instructions before microwaving any plastic container.

Can you put plastic in the dishwasher?

It depends on the type of plastic the container is made from. However, most plastics are safe to put in the dishwasher. Always consult the manufacturer’s instructions before putting any plastic container in the dishwasher.

What happens when you microwave non-microwavable plastic?

If you microwave a non-microwavable plastic container, it may cause the container to melt or warp. It is not safe to microwave any non-microwavable plastic container. Additionally, non-microwavable plastic containers may emit harmful chemicals when you expose them to high temperatures. So, it is best not to microwave them at all.

Is microwaving food in plastic bad for you?

No, microwaving food in plastic is not bad for you. However, not all plastic containers are microwavable; some may leach chemicals into your food when microwaved. So, it is always best to use microwavable plastics for microwaving food. Check out the microwave-safe symbol before microwaving any food on a plastic container.

Which plastic can you microwave?

Not all plastics can be microwaved. The plastics that are safe to microwave have a “microwave-safe” symbol. It is denoted by three wavy lines or a small red triangle with a microwave inside it. So, before microwaving any food on a plastic container, make sure the container has either of the symbols. If it doesn’t, then do not microwave the food.

Are KFC containers microwave safe?

KFC containers are not microwavable. The containers are made from plastic that can leach harmful chemicals into your food when microwaved. So, it is best not to microwave food in KFC containers.

Can plastic in the microwave cause fire?

Some plastic containers made from styrofoam and regular plastic wrap can heat up and melt when exposed to high temperatures. This can cause the plastic to catch on fire. So, it is crucial to be aware of which plastics are microwavable and which ones are not. If in doubt, don’t microwave the food.

How can we know food packaging is safe?

The best way to know if food packaging is safe is to look for the recycle symbol and check the bottom of the package. The recycle sign will have a number in the middle of three arrows. This number corresponds to the type of plastic the package is made from. So, if you are unsure whether or not a plastic container is microwavable, you can check the number on the recycle symbol to see if it is safe. 

Additionally, most plastic containers have “microwave-safe” printed on them. So, if you are in doubt, you can always check the container itself for any microwave-safe symbols or words.


So, can you microwave plastic? Yes, you can microwave most types of plastic as long as it has the microwave-safe symbol or words printed on it. Non-microwavable plastic containers will release harmful chemicals when microwaved, so it is best not to microwave them at all. Be aware of which plastics can melt or catch on fire when microwaved. If in doubt, don’t microwave the food.

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