Do microfibers from synthetic underwear pose health risks?

What's actually in it

Synthetic underwear is typically made from materials like polyester, which is a form of PET (polyethylene terephthalate). These fabrics are not just static pieces of clothing. They constantly shed tiny fibers known as microplastics and nanoplastics during wear and washing.

These particles are small enough to be inhaled or ingested. Once they enter the body, they don't just pass through without a trace. They can interact with your cells and tissues, potentially leading to harmful health outcomes.

What the research says

The science on these materials is clear: they are not inert. A 2026 study in Part Fibre Toxicol highlights that PET microplastics and nanoplastics carry significant toxicity concerns. The research explains that because these particles are so small, they can move throughout the body and trigger negative health responses.

Furthermore, synthetic materials are often associated with the release of airborne particles. According to a 2026 study in Environ Geochem Health, the emission of airborne microplastics from synthetic surfaces poses clear health risks, particularly to children. While this study focused on sports surfaces, it confirms that synthetic materials shed particles that enter the air we breathe.

When you wear synthetic underwear, you are in constant contact with a material that is actively breaking down into these microscopic plastic particles. Given the findings in this peer-reviewed research, it is safer to choose natural fibers that do not shed synthetic plastic debris.