A study has found that people inhale approximately 68,000 ultrafine plastic particles daily. Ultrafine plastics are much smaller than microplastics, about one-seventh the thickness of a human hair. Scientists have warned that this size can penetrate deep into the lungs, posing a risk of various diseases, including lung cancer.
On the 28th (local time), The Guardian reported that researchers at the University of Toulouse in France revealed that the estimated daily inhalation of ultrafine plastics, sized 1 to 10 micrometers (1 micrometer is one-millionth of a meter), could be as high as 68,000 particles. The results of this study were published last month in the international journal PLOS One.
The researchers confirmed that particles of this size could accumulate in the lungs via the bloodstream. Dr. Nadiia Yakovenko, who led the study, noted that "the number confirmed this time is about 100 times higher than the previously estimated daily inhalation rate," adding that "if ultrafine plastics accumulate in the body, it could lead to chronic pneumonia and lung cancer."
Unlike previous methods that could only capture particles larger than 10 to 20 micrometers, the researchers used Raman spectroscopy to detect ultrafine particles as small as 1 micrometer. Raman spectroscopy is a method used to analyze materials using light. When light hits a material, it is reflected, and depending on the material's unique energy, the light may gain or lose energy.
The researchers collected air samples from the interiors of apartments and cars to measure the concentration of microplastics. The analysis using Raman spectroscopy revealed that in an average household, there were 528 microplastics per cubic meter (m³). This translates to about 4,300 particles per square meter (m²), indicating that approximately 80,000 microplastic particles might be floating in a 20-pyeong apartment.
The microplastics measured in homes were comprised of 76% polyethylene. The researchers cited that indoor air is enclosed with poor ventilation, daily products such as clothing, kitchenware, and carpets release plastic particles, and that particles rise back into the air due to human movement.
A bigger problem was found in cars. The concentration of microplastics inside vehicles was about four times higher than that in apartments. This was attributed to microplastics lingering in enclosed, poorly ventilated spaces due to materials like the dashboard, door handles, and steering wheel.
Microplastics typically refer to plastic pieces smaller than 5 millimeters, with those measuring 1 to 100 micrometers categorized as ultrafine plastics, and those smaller than 1 micrometer classified as nanoparticles. They are generated from additives in consumer goods or from the degradation of larger plastics. Ultrafine plastics in the 1 to 10 micrometer range are so small that they can pass through the placenta, lungs, organs, capillaries, and even the blood-brain barrier (BBB), potentially spreading throughout the body.
In particular, they may contain up to 16,000 harmful chemicals, including bisphenol A (BPA), phthalates, and per- and polyfluoroalkyl substances (PFAS), which can increase the risk of respiratory issues, neurodevelopmental disorders, reproductive deformities, infertility, and cancer. According to last year's study by the American Chemical Society (ACS), prolonged exposure to ultrafine plastic particles has been associated with severe health problems. Workers in the textile industry appear to have a lung cancer incidence rate three times higher than normal.
To reduce exposure to microplastics, the researchers recommended reducing plastic products at home and using materials made of wood, metal, and natural fibers. They also suggested utilizing air purifiers and vacuum cleaners equipped with high-performance HEPA filters and performing regular ventilation and cleaning. However, they noted that while opening windows in cars could allow for ventilation, there are limitations as microplastics generated from tire wear and other outside sources could enter the vehicle.
References
PLOS One (2025), DOI: https://doi.org/10.1371/journal.pone.0328011
Environmental Science & Technology (2024), DOI: https://doi.org/10.1021/acs.est.3c09524