What happens when you store food in plastic containers

Plastic is inescapable in modern day. When it comes to stashing leftovers or picking up takeout, plastic containers seem to be a quick fix. 

Still, a growing number of studies pointing to the harmful effects of plastic on food have some people rethinking this decision. How valid are these concerns, and can you keep using plastic containers?

Concerns about plastic usually revolve around fears the substances and chemicals inside the plastic can leach into food. Bisphenol A, polyethylene and polypropylene are among the most common chemicals used in plastic containers. These chemicals have been linked to potential health effects like increased blood pressure, Type 2 diabetes and cardiovascular disease, especially for vulnerable individuals like children or pregnant women. 

But experts say you don't need to throw away your plastic containers just yet.

According to the U.S. Food and Drug Administration, there isn’t sufficient scientific evidence showing the microplastics and nanoplastics from plastic food packaging can migrate into foods and beverages.

The real danger comes when the plastic container is heated, said Dr. Joseph S. Alpert, a professor of medicine at the University of Arizona. Microwaving excites plastic molecules and causes them to, indeed, sneak into food.

As for storing food in plastic in the fridge for a few days, it is “probably reasonably safe,” said Alpert. He added the safest bet is still to store food in glass containers that do not contain lead.

What is the healthiest container to store food in?

There are many commercial plastics on the market, and the answer depends on determining what type you’re using. The first place to check is the identification number, officially known as Resin Identification Codes, embedded on every plastic container. Located within a small triangle, they range from 1 through 7 and offer clues as to what the container is made of and whether it is recyclable. 

It is generally considered OK to store food in plastic containers labeled with a 1, 2, 4 or 5, though containers labeled 1 should ideally be stored in cool environments and not be reused. Plastic marked with a 3, 6 and 7 should be used minimally around food to limit potential health impacts.