Microwaves have become very useful in our lives. We can say that they are the new wave of the moment.
Putting plastics in a microwave is dicey, but the longest you can leave them in a microwave should be 30 minutes.
Follow me in this article, as I go into detail about plastics and microwaves.
Is it safe to microwave plastic?
Plastic is a synthetic material that has proven to be a part of the very fabric of our lives. We almost can’t do it with plastic, as we have it serving a purpose in various sectors. Its functions range from the automobile industry to the medical field and even to common household goods. Plastic has become one of the vital items that we use for packaging our food and beverages.
Plastic is made up of very long chains of polymers. Plastic can be made from petroleum, as well as other materials like wood pulp. There are identification numbers used to differentiate the class from which each plastic product comes from. These numbers range from 1 to 7 and are usually indicated at the base of most plastic products.
The seven types of plastic are
- Polyethylene Terephthalate (PET or PETE): This material is lightweight, and commonly used in packaging food. e.g. mayonnaise jars, beverage bottles, etc.
- High density polyethylene: This kind of polyethylene is high density and quite resistant to moisture and chemicals. It is used in making detergent containers, milk jugs, butter containers, etc.
- PolyVinyl Chloride: This plastic product is quite hard and rigid and is also resistant to chemicals. It finds great use in construction as it is used for making plumbing and construction pipes. It is also used as an insulation material for wires and cables. However, it must be noted that PVC is one of the materials that leaches the most chemicals.
- Low density polyethylene: This is low density and is a clearer and more flexible form of HDPE. It finds application in carton liners and squeeze bottles.
- Polypropylene: This is one of the most durable forms of plastic, as it is quite heat resistant. It is used in the production of bottle caps, hot food containers, diapers, packaging tapes, etc.
- Polystyrene: It is also known as “styrofoam.” A very lightweight plastic that is low cost and insulated well. It is very common in the food and packaging industries. It is used to make takeout tea cups, the packaging for appliances, plates, etc.
- Other: This refers to all other types of plastic that don’t fall under the earlier mentioned six categories. And it includes polycarbonate, polylactide, acrylic, fiberglass, styrene, nylon, etc. Eyeglasses, clear plastic spoons, and sports bottles are just some of the many products that can be made from this kind of plastic.
Now having established the different kinds of plastic, the question really is whether microwaving is a safe thing to do. Some plastics have some stabilizers and additives in their makeup. These chemicals are added because of one desired property the producers want to see in the finished products.
However, the problem with some of these additives is that when microwaved, they can easily leach into your food and beverages.
Some chemicals of concern are Bisphenol A and phthalates. These chemicals are added to create more flexibility and durability in the plastic. The downside is that these chemicals can cause health issues. They are endocrine disruptors. A has been linked to causing hormonal cancer, obesity, genetic disorders, etc.
Due to this, the Food and Drug Administration (FDA) has banned the use of BPA in making baby food packaging like baby bottles and sippy cups.
Even at that, studies have shown that the supposed BPA-free plastics still release phthalates into food when microwaved.
This tells you that you should avoid microwaving food. The consequences are there to see.
At what temperature does plastic leach?
Plastic made from Polyethylene Terephthalate (PET) is one of the major culprits of leaching chemicals. The chemicals that leach from them include antimony and bisphenol A. These are both dangerous chemicals, as earlier discussed. PET is commonly used to produce water bottles. A study was carried out on these bottles, to test how much antimony and BPA were leached at various temperatures. Below are the results.
| 4°C | 25°C | 70°C | |
| Antimony | 1.88–8.32 ng/L | 2.10–18.4ng/L | 20.3–2604 ng/L |
| BPA | 0.26–18.7ng/L | 0.62–22.6ng/L | 2.89–38.9 ng/L |
From this table, it is clear that plastic begins to leach even at low temperatures of 4 °C, and as the temperatures increase, the amount of chemical leaching increases.
How do I know if plastic is microwave safe?
The easiest way to know if a plastic is microwave safe is to look for the tag on the bottom that reads “microwave safe”. You can also look out for the microwave safe symbol, which consists of three wavy lines. The meaning of microwave safe refers to the fact that your plastic will melt in the microwave. This has nothing to do with whether plastic leaches harmful chemicals into food.
Plastics labeled #5 are generally safe for microwave heating. However, plastics labeled # 7, which is polystyrene or styrofoam, should not be used in microwaves. They are not microwave safe.
Which plastic numbers are microwave safe?
Microwave safe is a term that is used to refer to plastics that are heat resistant and quite durable under high temperatures. There are some plastics that have a low melting point and do not do well under heat. Most of them are not BPA free, and microwaving them can cause issues for you, because they easily leach this toxic chemical into food.
I will be listing below some plastics you can refer to as microwave safe and the ones you can’t.
Plastic #2: This is high density polyethylene, or HDPE. They are microwave safe. It is very common to see them used in producing bottles for potable drinks and liquids. You can also see it being used to make milk jugs. HDPE is quite durable as it has a high melting point. It also doesn’t have an issue with wearing out, so you can be assured that it won’t contaminate your food. It is also very recyclable.
Plastic #5: This is polypropylene. It is also quite heat-resistant and durable. It is actually the best bet for microwave use. Its melting point is up to 250 degrees Fahrenheit. It is quite clear, and even after being microwaved, it feels cool to the touch.
Plastic #1: This plastic is called Polyethylene Terephthalate. As already established before, phthalates are not safe for your health. These chemicals can easily leach into your food and cause great health issues. In addition, this type of plastic has a low melting point of 120° F.
Plastic #6. This plastic is a class called styrofoam or polystyrene. It has a very low melting point, which means that it can easily melt. It leaches some toxic chemicals into your food.
Plastic #7. This category includes polycarbonates. They are not microwave safe due to the toxic chemicals they leach. In addition, some of them have low melting points.
What happens if plastic melts in your food?
Generally speaking, if plastic were to melt in your food, you might not suffer any noticeable toxic effects. This is because plastic is generally indigestible by your body. As a result, the plastic will pass out and be excreted by your excretory system. However, this should not be a regular occurrence, as those chemicals, Bisphenol A and phthalates, can leach from these plastics and cause several health issues.
How do you clean the oven after melting plastic?
The best way to remove melted plastic from a microwave is to use a bag of ice on the plastic residue. This will cause the plastic to harden and become brittle. This way, it is easily pliable and can be scraped away.
For ovens with a self-cleaning feature, you should turn the oven to a low heat setting and let it heat for a few minutes. This will make the plastic easy to remove.
However, it must be noted that when scraping, you should make use of a wooden spatula. Metal utensils can scrape the surface of the oven.
How long can you microwave something?
The time duration for microwaving shouldn’t pass 30 minutes. One of the reasons for this is that if your food is injected with heat for a long time, it can dry out, and this can cause issues for your food. Also, microwaving for a long time can put a strain on your microwave’s magnetron, and this can shorten the lifespan of the microwave.
Can you microwave plastic for 30 seconds?
Yes, you can. This is a relatively short time for anything serious to happen. Generally, plastics are transparent, and they don’t absorb the waves. So no harm will come to them.
Can I microwave Tupperware?
Yes, you can. Tupperware is generally BPA-free and microwave safe. They are majorly made from plastic #5 and hence microwave safe. However, you should still check the base of your Tupperware for the microwave symbol.