Is it Safe to Put a Plastic in the Microwave? – Myths Debunked!

Last Updated on August 13, 2021


Annabelle Watson

Annabelle is an experienced food writer and editor. She focuses on common sense, easy to replicate recipes formulated to help keep things fresh and exciting while fitting into her day to day life as a wife and mother.

Microwave Lunch Explosion

Photo: Microwave Lunch Explosion by daryl_mitchell

We’ve taken the time to research this question, and we’ve come up with some helpful information to guide you through the best ways to use plastic in the microwave, or not.

1. Plastic and Your Microwave – What’s the Problem

Plastic in the Microwave

Photo Courtesy: Urban Company

So science is starting to tell us, more and more often that plastic isn’t great for foods and beverages. Many plastics contain chemical compounds that aren’t good for our bodies. Some plastics that contain these products are being removed from the market, but that doesn’t solve the problem of the plastic that you have in your cabinets today.

What is even more confusing is that now you can buy plastics that are supposed to be safe for the microwave. But are they really? And do you really want to expose your family to chemicals that aren’t good for their health?

2. Science and Regulations

Before we delve into the answer to the question of using plastic in the microwave, it is helpful to know why this is a problem and what we are doing to fix the problem.

Plastics contain two man-made chemicals that are the source of all this controversy. Phthalates and Bisphenol A (BPA) are chemicals that are added to plastics to help them maintain their shape and pliability. They are why lots of plastic containers can bend so easily without breaking. 

However, these two chemicals have become linked to some pretty strange stuff. Both Phthalates and BPA are called “endocrine disruptors”. This means that they mess with your hormones and make your body do stuff it shouldn’t. For adults, this isn’t a huge issue, but for growing children, endocrine disruptors can hinder normal growth and development. They are bad stuff.

The problem here is that while science is starting to understand the link between delayed development in children and plastics, there just isn’t enough evidence to link Phthalates and BPA to developmental issues. 

And because there isn’t a solid link, they are not regulated in plastic products. That is why you still find tons of plastic containers holding food, and designed for use in the microwave.

3. But Can You Use Plastic in the Microwave?

Plastic in the Microwave

Photo Courtesy: The Jakarta Post

Knowing what we now know, this is a tricky question. Can you use plastic in the microwave, yes. Should you use plastic in the microwave? Maybe not.

Phthalates and BPA tend to leach from plastics when exposed to heat, so it makes sense that if you are microwaving foods in plastic, you are probably adding these chemicals into your food.

If you are going to use plastic for storing and heating foods, you should avoid some particular types of plastic. Even plastic containers that claim to be safe for reheating foods, might not be, so look carefully at the recycling codes on plastic containers, before you use them for storing foods. Here are the recycle codes that you should always avoid:

  • Code 3 = Contains phthalates
  • Code 6 = Contains styrene
  • Code 7 = Contains Bisphenol

If you are going to use plastics to store food, pick those that have recycling codes 1, 2 and 4. Number 1 and # 2 plastics are BPA-free and #4 is a good alternative to containers with a #7 recycling code. Also, never reuse containers that foods are packaged in, in the microwave (butter, sour cream or yogurt tubs).

There are now microwave safe plastics, but make sure you are only using containers that are in good condition. Plastics that are scratched or damaged can leach chemicals into your foods.

4. Alternatives to Plastic

kitchen counter

Really, the best answer is to find containers that are better than plastic. There are a lot of microwave safe alternatives, you just need to be willing to use them.

Glass – Glass is really the best alternative to plastic. Its been around for so long, and there are really great glass containers that can go from the fridge to the microwave, and in some cases even to the oven. Look for Pyrex glass or something comparable as a good multi-purpose storage and heating container. 

This type of glass was originally made to be used at high heat in laboratories, so it’s a perfect solution for the kitchen. The cool thing is that you can buy complete food storage sets, with lids that are made from glass. The downfall with glass? It can chip, crack or break if it isn’t handled with care.
Ceramic –  Like glass ceramic has been used to store food for a long time. Longer even than glass. Ceramic is a little less durable than glass, but it works just fine. However, not all ceramic is microwave safe, so do make sure that the product you select has the words “microwave safe” on the bottom.

5. Other Things You Should Know

Here are a few other bits of information you should know about using plastics in the kitchen.

Heat is the enemy of plastic. Yes, your stove will melt plastic, but did you know that your dishwasher can also cause chemicals to leach from your plastic storage containers? Avoid washing your plastic containers in the dishwasher.
Plastic wrap isn’t a good alternative. If you need to cover food in the microwave, try parchment paper, wax paper or a paper towel.
Don’t reuse take out containers. They are intended to be single use. When you’re done with them, put them in your recycle bin.

In general, it is probably a good idea to not use plastic in the microwave, even if it says it is “microwave safe”. But, we’re also not saying you need to completely give up your plastic food containers. 

Use your plastic containers to store your food, but skip the microwaving. There are plenty of great alternatives for heating your foods that are safe and are a better, healthier choice for your family.

Further reading: What size of countertop microwave should you get