Microplastics–tiny particles of plastic no longer than five millimeters–are best known for polluting water (and, by extension, fish, sea salt, and beer). But microplastic is also in the air: One study estimates that each meal we eat may contain an average of 100 plastic fibers that have wafted off products like polyester sweatshirts or carpet. As the plastic travels through indoor air, we’re probably also breathing it in.
One air purifier company is now marketing its products for their ability to filter out microplastic, along with more standard air pollutants, like pollen, mold, smoke, and dust mites. The tagline currently splashed across the company’s website reads “Breathe plastic-free air.” While other air purifiers can also filter tiny plastic fibers, the Sweden-based company, called Blueair, says that it can remove smaller particles than a standard HEPA filter, down to 0.1 micrometers in size; a standard filter typically removes particles as small as 0.3 micrometers.
When the devices pull air into the purifier, the particles are electrically charged, making it easier to efficiently catch them in a filter. (It’s worth noting that this type of ionizing purifier can cause sometimes cause another problem–increasing ozone pollution in the air–but Blueair’s devices are certified to be safe.) The company also sells a separate air monitor, which sends pollution readings to a smartphone app. The monitor detects the level of PM 2.5 pollution–ultrafine particles with a diameter less than 2.5 micrometers, or 3% of the width of a human hair–including both plastic and other pollution. The air purifier can be programmed to automatically turn on when the monitor senses a certain level of pollution.
Blueair seems to be the only air purifier company making a pitch about microplastic. “We’d like people to be aware of these pollutants from plastic particles,” says Kevin Luo, a senior air filtration specialist for the company.
Still, though Luo calls the pollution “dangerous,” there’s little scientific understanding yet of the potential impact on human health. A handful of studies have shown that microplastic is in the air, both inside and outside. A paper published earlier this year about plastic microfibers notes that if plastic fibers are tiny enough to enter the lungs–and aren’t coughed out, as they may usually be–they’re unlikely to degrade. As it irritates the body, the plastic could lead to inflammation; cancer could theoretically follow prolonged inflammation. Plastic could also contain dyes or other additives that could harm health. But none of the effects are proven yet. “There’s an urgent need for data on the human health impacts of fibrous microplastics,” the paper says.
It isn’t clear how much purifying the air in a room can help, given the ubiquity of plastic–the world now produces around 60 million metric tons of plastic textile fibers alone–and the fact that microplastic pollution is also outside. But in a bedroom, where you probably spend nearly 60 hours a week, it’s possible that it could be beneficial. Blueair plans to do some research itself. “We’re working on a project to collect filters from users and to study what the filter has collected from the air, and how many and which plastic particles are collected,” says Luo. The company also recommends trying to reduce the amount of plastic inside your home. Even a backpack or shirt or pair of shoes made from recycled plastic water bottles–while it might reduce waste in the outside world–could be slowly adding to your personal cloud of microplastic.