There’s no escaping plastic. It’s in the oceans, in Arctic snow, and now, more alarmingly than ever, in the very air we breathe inside our homes and cars. Yes, you have microplastics inside you; about a spoonful per week, according to some estimates.
In a new peer-reviewed study published in PLOS ONE, researchers from the Université de Toulouse in France report that people may be inhaling up to 68,000 microplastic particles each day — and not just any particles, but the fine, lung-penetrating kind that are 1 to 10 micrometers in diameter. That’s about 100 times more particles than previously estimated.
Inhaling The Invisible
Nadiia Yakovenko and colleagues analyzed 16 air samples from their own apartments, as well as from their own cars in realistic driving conditions. These are samples from real-life environments, probably similar to what many of us are exposed to every day.
“People spend an average of 90% of their time indoors, including homes, workplaces, shops, transportation, etc., and all the while they are exposed to microplastic pollution through inhalation without even thinking about it,” says Yakovenko. “Thus, we investigated our homes and personal vehicles, environments that are often overlooked, yet play a major role in our daily exposure.”
This isn’t the first study to analyze air samples (and find microplastics). But prior research mostly focused on particles ranging from 20 to 200 micrometers in diameter. In this study, researchers used a technique called Raman spectroscopy to measure concentrations, including those ranging from 1 to 10 micrometers across.
Herein came the shock. Researchers found up to 100 times more microplastic particles than previous studies, and the vast majority of those were small ones. Yakovenko says that these small particles are the most dangerous, because they can sneak into the lungs.
“The key finding of this work is that more than 90% of the plastic particles we detected were smaller than 10 µm. These particles are smaller than a speck of dust and more than 7 times thinner than the width of a single strand of hair. Upon inhalation, they can penetrate deep into the lungs. The concentration we found is 100-fold higher than previous extrapolated estimates,” the researcher says. “Microplastics in the air, especially indoors, may be an invisible threat we are only beginning to understand.”
Your Car Is a Plastic Box on Wheels
The team measured a median of 528 microplastic particles per cubic meter of air inside homes and 2,238 particles per cubic meter in cars. Most of these particles are not the long fibers associated with clothing, but rather tiny plastic fragments, likely shed from common materials: carpets, curtains, upholstery, even paint.
“What surprised us the most was how much microplastics were present in the air of the environments we consider safe and familiar, like our homes and cars. We often associate plastic pollution with oceans or industrial areas, but our findings showed that the everyday indoor environment where we spend most of our time can be a major source of human exposure.”
The discovery that car cabins are microplastic hotspots is especially unsettling. Cars are packed with plastic — from dashboards to seat fabric — and are exposed to sun, heat, and friction. These conditions can accelerate the breakdown of polymers, releasing particles into the tightly enclosed airspace. The average American spends over 300 hours driving, which is a substantial exposure time.
Of course, the question is what happens when these particles reach the lungs? The study didn’t explore these effects. In fact, we’re only now starting to understand how microplastics affect our health.
“When microplastics are inhaled, these tiny particles can enter deep into our respiratory system and potentially cause inflammation or irritation. Microplastics carry toxic additives, such as bisphenol A, or phthalates, which can reach our bloodstream. While research is still ongoing, there is concern that long-term exposure to microplastics and their additives may contribute to respiratory problems, disrupt endocrine function and increase risk for neurodevelopmental disorders, reproductive birth defects, infertility, cardiovascular disease, and cancers.”
So, What Can We Do?
The truth is, everywhere we look, we see microplastics. There’s no official indoor air quality standard for microplastics. The study’s authors hope their work will push the issue onto the radar of public health agencies.
But it will take time until that happens.
Meanwhile, better ventilation, avoiding synthetic textiles, and reducing friction and wear on plastic surfaces may help limit exposure.
But even then, these efforts may only slow the tide. Microplastics have become a permanent feature of the Anthropocene, drifting into our bodies without our permission.
“I hope that our findings will raise awareness about indoor air as a significant source of microplastic exposure through inhalation. This knowledge could help guide future public health recommendations, indoor air quality standards, or even changes in products and materials we use. As for the next step, our team plans to study a wider variety of indoor environments and explore how different conditions or daily habits might affect the level of microplastic exposure. Ultimately, our goal is to better understand the sources and behavior of microplastic particles indoors in order to more accurately assess their potential health effects,” Yakovenko concludes.
Journal Reference: Yakovenko N, Pérez-Serrano L, Segur T, Hagelskjaer O, Margenat H, Le Roux G, et al. (2025) Human exposure to PM10 microplastics in indoor air. PLoS One 20(7): e0328011. https://doi.org/10.1371/journal.pone.0328011
