If you've got some leftover Dominos pizza that you want to warm up you might consider just throwing the pizza in the microwave still in the box.
But before you do you might find yourself wondering can you microwave a dominos pizza box or is that dangerous?
I love dominos every now and then and when I buy it for the kids there is always leftovers. I've been known from time to time to put the entire Dominos box in the microwave to warm up the pizza the next day.
But I wanted to see if this was actually safe or if it would catch on fire. So I did some experiments myself as well as some research into whether or not the cardboard might leach harmful chemicals into my pizza and here's what I found.
You can microwave a dominos pizza box with pizza in it for a short period of time without issue but you SHOULDN'T. Too long in the microwave and the box can actually set of fire plus they are made from recycled cardboard which studies have shown to contain harmful chemicals that leach into your food.
I was super surprised how quickly the box actually caught on fire and was even more surprised when I looked into the potential health issues with heating up food in a cardboard box.
Can You Warm Up Dominos Pizza In The Box?
First lets cover whether or not pizza will heat up in the microwave inside the box.
The answer is yes, Dominos pizza will heat up in the microwave still in the box. The microwaves will pass through the box and warm up the pizza inside just fine.
I personally tested this in the video you can see below (where I set the box on fire) and in 1 minute the pizza warmed up so much it was too hot to even eat.
Is It Safe To Microwave a Domino's Pizza Box? Will It Catch On Fire?
What about safety? Is it safe to microwave a Dominos pizza box or is it possible for the pizza box to catch on fire?
Well after 1 minute with pizza in it the pizza had warmed up but the box looked completely fine.
There were no darker areas of the box which would indicate extreme heat or smouldering. The box looked completely normal.
However, when I put the box back in the microwave without pizza in it within 2 minutes the Dominos box had caught on fire, and that fire quickly spread as the box burned quickly.
You can see what happened in the video below:
From the way the smoke formed and the way the fire started it appeared that the box actually caught on fire from the inside and then burned its way out.
This would make sense, because the box is closed and air can't get out the air inside the box could get super heated and ultimately become hot enough to set the cardboard on fire.
Dominos pizza boxes are also made of a cardboard a type of cardboard with an inner and outer layer and a wave like pieces of cardboard in between to give the sides some volume and also to help insulate them.
This type of cardboard allows for larger build up of heat compared to say a flat piece of paper. This makes them more likely to catch on fire.
Are Domino's Pizza Boxes Toxic?
Now I can't speak directly for Dominos as I don't know exactly where they source the cardboard for their boxes but recent studies have shown that recycled cardboard contains harmful mineral oils which can be toxic to humans and even cause cancer.
I would avoid reheating pizza in Dominos boxes in the microwave because the pizza boxes may contain toxic chemicals and mineral oils that may leach into your food under high heats.
The BBC put out an article highlighting that recycled cardboard contains toxic mineral oils that can cause all sorts of health problems. These toxic chemicals likely come from newspaper ink that is then recycled into cardboard.
Government scientists in Switzerland found quantities of mineral oils between 10 and 100 times above the agreed limit in foods like pasta, rice and cereals sold in cartons made from recycled cardboard.
An apparently half of cardboard in Europe is recycled cardboard.
This study also showed that paper based food containers (such as pizza boxes) can leach chemicals into your food, especially if it is hot (which pizza usually is).
Also, when I wrote my article on can you microwave paper towels I discovered that a lot of paper products contain harmful chemicals called dioxins which are also likely carcinogenic.
Given that recycled cardboard is cheaper than brand new cardboard chances are pretty high that Dominos would be using the cheaper stuff.
They are obviously focused heavily on low prices and saving costs would be important to them.
Their box also encourages people to recycle, which makes me think it's made of recycled cardboard.
So while there have been no specific tests done on Dominos pizza boxes specially I personally wouldn't want to heat up my pizza in the Dominos box.
I would now even go as far as to quickly remove the Dominos pizza from the box when I get it to minimize the leaching of chemicals onto my pizza.
When I looked into microwaving styrofoam I found that leaching occurred a lot more once the temperature of got over 90-100ºC and I would imagine it would be similar for cardboard.
Would I Personally Microwave a Domino's Pizza Box?
Given the experiments I have done and what I have learned about the potential toxic chemicals in recycled cardboard I personally would NOT microwave a dominos pizza box.
Firstly, the boxes are prone to catch on fire.
The box caught on fire quicker than paper towels and faster than scrunched up paper or scrunched up cardboard.
There was also way more material to catch on fire compared to a paper plate or something small which means the fire burns bigger and is more dangerous.
Add to that the fact that there may be harmful chemicals in the box that could leach onto my food and increase my chances of getting cancer. No way am I going to be microwaving Dominos pizza boxes ever again.
I still love Dominos though and I'll still order it from time to time.