Are styrene foam takeout boxes putting styrene in your hot food?

What's actually in it

Styrofoam-style takeout boxes and cups are made from polystyrene. The plastic is held together by single units of styrene, a chemical that the U.S. National Toxicology Program calls "reasonably anticipated" to cause cancer. When hot food or oily food touches the foam, styrene moves out of the container into the food.

Microwaving or pouring boiling soup into the cup makes it worse.

What the research says

A 2026 study in Food Chem measured styrene moving from foam takeout containers and cups into food. The dose climbed with heat, fat, and contact time. Hot soup in a foam cup ended up with detectable styrene within minutes. Cold drinks were close to zero.

The team called foam takeout a meaningful daily source for people who eat lunch out of foam boxes.

When you order takeout, ask for paper or cardboard containers, or move the food to a real plate as soon as you get home. Bring a steel tin to a deli or food truck. Skip foam coffee cups for hot drinks: a ceramic or steel travel mug works for half the cost over a year.