Wearing Polyester or Nylon hijabs? What new science finds in the Brains

Read this before you wrap your hijab tomorrow. If your scarf is polyester or nylon, you’re wearing, and likely breathing, tiny plastic fibers every day. Those “invisible” microfibers don’t just disappear. They shed into indoor air, the place we spend most of our lives, and become a steady exposure you inhale or accidentally ingest. Multiple scientific teams have actually measured this: in apartments in Denmark, Vianello et al. used a breathing thermal manikin and found airborne microplastics in every home they sampled (1.7–16.2 particles per m³, predominantly polyester). The take-home was blunt: indoor air is a direct exposure route, and synthetics are present and inhalable.

A national health institute review from the Netherlands (RIVM) pulled together the early literature and put numbers on it: typical indoor concentrations across studies ranged from ~1.6 to 9.3 microplastics per m³ (peaks to ~20), with textiles highlighted as the main indoor source due to fiber shedding during normal wear and care.

Now, does any of this plastic get inside the body? Yes. A Dutch team from Vrije Universiteit Amsterdam, led by Heather A. Leslie and Marja H., developed a validated pyrolysis-GC/MS method and reported the first detection and quantification of plastic particles in human blood. That’s direct evidence of systemic bioavailability from everyday exposure.

And what about the brain? In 2025, a peer-reviewed paper in Nature Medicine “Bioaccumulation of microplastics in decedent human brains” analyzed autopsy tissues. They found that micro- and nanoplastics were 7–30× higher in brain than in liver or kidney with ~50% higher brain concentrations in 2024 versus 2016 samples and notable deposition along cerebrovascular walls; dementia cases had even greater loads.

There’s also a nearer-to-home respiratory angle for nylon and polyester worn right by the mouth and nose. Human and murine airway organoid experiments show that nylon and polyester microfibers can impair the development of airway epithelium. That doesn’t prove day-to-day harm from a scarf, but it establishes biological plausibility that certain synthetic fibers and their additives are not inert to airway tissue.

So what should you do with this information? You don’t need to panic, you need a plan. First, reduce plastic where it’s easiest and most frequent: what you wear all day, right next to your breathing zone. Polyester and nylon are plastics; they shed plastic microfibers. Regenerated cellulosics like bamboo and viscose are not plastics; while any textile can shed fibers, cellulosic lint is not microplastic by definition. Combine smarter fabric choices with gentler care (lower-friction washes, skip the hot tumble when you can, use filters/bags if you must machine-wash synthetics) to cut shedding and exposure.