Your Plastic Food Containers Are Releasing Nanoplastics

Your polypropylene food containers are releasing nanoplastics. Not in extreme conditions. Under normal use: rinsing with hot water, storing food, everyday washing. A 2025 study measured up to 3.7 micrograms per liter of nanoplastics leaching out, plus up to 10.8 micrograms per liter of larger microplastics.

What the study found

Researchers published in Journal of Agricultural and Food Chemistry tested polypropylene food containers under simulated everyday conditions. They found nanoplastics in both hot and cold water, but hot water released significantly more. The particles ranged from 122 to 397 nanometers, small enough to cross cell membranes.

These weren't theoretical particles. The researchers chemically confirmed they were polypropylene using multiple analytical methods. The particles are real, they're in the water that touches your food, and they're going into your body when you eat.

Which containers are affected

Polypropylene is labeled PP or recycling code 5 on the bottom of containers. It's one of the most common plastics in food storage: leftover containers, deli containers, meal prep boxes, microwave-safe containers. Hot liquids and dishwasher cycles make it worse.

Glass and stainless steel don't shed particles. No nanoplastics, no microplastics, nothing migrating into your food. Browse glass food storage containers and stainless steel alternatives to replace what you have now.

Source: Shi K et al. (2025). Journal of Agricultural and Food Chemistry.