Can polypropylene in yogurt cups cause cancer?
No study proves that one polypropylene yogurt cup causes cancer. Studies do show that plastic food containers can release microplastics and nanoplastics, and polypropylene microplastics have been found in human blood and cancer tissues.
What's actually in it
Many yogurt cups are made from polypropylene, also called PP or plastic number 5.
Polypropylene is not the same thing as cancer. The real concern is that plastic food containers can shed tiny plastic particles, especially with heat.
What the research says
A 2023 Environmental Science & Technology study tested plastic containers and reusable food pouches with water and acidic food simulants. Microwave heating caused the highest release of microplastics and nanoplastics. Some containers released as many as 4.22 million microplastic particles and 2.11 billion nanoplastic particles from 1 square centimeter in 3 minutes.
A 2026 Naunyn-Schmiedeberg's Archives of Pharmacology study found PET and polypropylene microplastics in human blood and cancer tissue samples. The study did not prove that polypropylene causes cancer.
The useful rule is simple: do not microwave yogurt cups, and do not reuse scratched plastic cups for food. Move food into glass storage jars before heating or storing leftovers.
The research at a glance
| Study | Journal | Year |
|---|---|---|
| Assessing the Release of Microplastics and Nanoplastics from Plastic Containers and Reusable Food Pouches: Implications for Human Health. | Environ Sci Technol | 2023 |
| Polyethylene terephthalate and polypropylene microplastic bioaccumulation in human blood and cancerous tissues in Algerian cases. | Naunyn Schmiedebergs Arch Pharmacol | 2026 |