The Best Air Purifiers May Be Made From 2 Unusual Houseplants

Houseplants make for beautiful backdrops on Instagram, but they have their downsides. You need to water them. Your cat eats them. Your orchids cost $20 a pot and last as many days. You can’t go on vacation without sacrificing at least one at the altar of rest and relaxation. But one major perk of owning a houseplant is that they are a natural air filtration system.

It’s biology 101: plant pulls in carbon dioxide and other harmful gases, plant breathes out oxygen. But despite at least one viral (unreplicated) NASA study showing the power of houseplants to clean the air and beautify your space, relying on houseplants to purify the air in your apartment is less of a good idea than just cracking a window.

We hate to break it to you, but most houseplants don’t remove that much C02 or profoundly improve your home’s air quality.

“It takes a decade or more for an air-purifying plant to filter 0.2 percent of the surrounding air,” says Jamie Mitri, founder and CEO of Moss Pure, a lifestyle brand that bridges home décor with personal health. Mitri worked as an environmental engineer for several years and has degrees in chemical engineering and biology. Her business is one of a few trying to lower indoor carbon dioxide levels using photoautotrophs — organisms like moss and algae that lack roots but pull nutrients from their environment.

Dan Fucich of AlgenAir also has a scientific background. He and co-founder Kelsey Abernathy were each wrapping up their Ph.D. in marine biotechnology when they created Aerium, the first consumer product on the market using algae to decrease indoor C02 levels.

The idea is founded on a concept already being tested outdoors in response to the jaw-dropping amount of carbon dioxide the U.S. emits every year. The country’s greenhouse gas emissions totaled 13.2 trillion pounds of carbon dioxide equivalents in 2020 alone. While planting trees is the fashionable solution to this problem, the average mature tree can only absorb around 48 pounds of carbon dioxide per year. Meanwhile, moss is so good at converting carbon dioxide into oxygen that, were it to blanket an average-sized American lawn, moss could absorb as much C02 as about 275 mature trees, according to The Oxygen Project. It’s not as aesthetically pleasing, perhaps. But combined with the fact that algae make 60 percent of the world’s oxygen, according to Fucich, you have a compelling argument for refocusing the attention given to trees on algae and moss. Already, companies like Brilliant Planet are farming algae for carbon capture, and Green City Solutions aims to construct living moss walls for cleaner city air.

But could moss and algae grow (pun intended) on individual consumers, too? “Given recent global events, people are finally starting to wake up to the problems of poor recirculating indoor air quality,” says Fucich. And people want a natural solution — it speaks volumes that the U.K. brand Briiv recently joined Goop’s ranks of natural homewares. It makes its air purifier primarily from preserved moss and other natural air filters, like coconut fiber.

Plants, but not as you know them

Moss and algae are plants, but they don’t have roots to suck up nutrients from the environment. Instead of roots, moss uses rhizoids, small hairlike structures that also anchor the plant to terrain or tree bark. Some species of moss draw nutrients through the rhizoids, while others pull in moisture and minerals from rain through the plant’s highly absorbent surfaces. Moss then expels oxygen back into the air. Algae uses sunlight and C02 to make energy and feed itself by creating complex molecules like fats, carbohydrates, and proteins. Like trees and moss, it uses photosynthesis to absorb carbon and releases oxygen back into the air. What’s more, algae absorbs the carbon and uses it to form more algae. One of the earliest life forms on Earth, algae may have had a hand in creating the oxygen-rich atmosphere we enjoy.

Whereas a tree must expend energy, material, and resources to fight gravity, collect water, work to reproduce, fend off herbivores, and more, the only part of the tree that is actually photosynthesizing is the leaves. These make up only around 5 percent of its total biomass, says Fucich. Hence, trees are less efficient than algae and moss at producing oxygen.

Moss and algae grow best in their natural habitats. Outdoors, moss can grow well in the shade, but in a home, they require more light to keep the moss from drowning and the right temperatures to ward off rot from settling in. Mitri explains how she started to think about how moss could fit inside a home.

“I realized that live moss has the potential for many health benefits, such as air purification,” says Mitri. “But companies weren’t using live moss… no other company was able to keep live moss alive indoors or outdoors for more than a few days.” So far, no one has created an effective air filter out of moss, she says, and many live moss products are bulky and need a lot of watering and electricity.

The best air purifiers ever?

Most of the time, when you see moss in a home, it is dried or preserved. It looks great: #Mosswalls has been viewed on TikTok 15.7 million times. But nearly all of these are moss walls treated with chemicals and dyed different colors — decorative and pretty, but ultimately also dead and thus unable to absorb as much C02 (although, surprisingly, preserved moss can still filter the air). After some time, the moss will flake, fade in color, and need maintenance or replacement.

Right now, Briiv is perhaps the most popular biophilic air purifier, using 100 percent biodegradable and compostable preserved moss. It also uses 90 percent natural and renewable materials and provides the oxygen-making power of 3,043 medium-size houseplants. “As [moss] is a completely natural material, ethically sourced, picked, and preserved, it adds to Briiv’s status of the world’s most sustainable air purifier,” says James Whitfield, Briiv’s managing director.

“While we’re proud of Briiv, it still contains things like electronics that aren’t recyclable, so the aim would be to find alternatives for these components to make it 100 percent plastic-free,” he says. The brand is also working on refurbishing older units and giving them a second life.

Mitri claims that her Moss Pure product, by contrast, is made of living moss and requires no watering, sunlight, or extra maintenance. Moss Pure has been installed in living rooms, bathrooms, hotel lobbies, outdoor walls of restaurants, and even hair salons, she says.

According to the company, Moss Pure’s products were tested for air purification by a U.S.-certified laboratory, and the results found that, in two minutes, Moss Pure cleared the air of 30 percent of carbon dioxide and pollutants like dust, allergens, and viruses. The patent for the brand’s proprietary technology is pending.

On the other hand, Fucich and Abernathy’s Aerium works by pumping air into its glass container filled with billions of tiny microalgae. The device’s LED light provides for continuous photosynthesis. A pump circulates the water, keeping the algae alive and moving. Once the algae have finished their life cycle, the Aerium’s contents can be poured as is into houseplant pots and used as a fertilizer. But Fucich anticipates other applications of the dead algae down the line, surmising that algae might in the future grow inside our homes and be regularly cultivated as a sort of homemade biofuel or garden fertilizer. It might even be possible to use the algae to help solve problems to do with “human and animal nutrition,” Fucich says.

Currently, AlgenAir’s Aerium is the only indoor air purifier made from algae. It offers the same photosynthetic capacity as 25 houseplants. “And we have begun to scale the patent-pending technology used in the device to clean larger volumes of air,” Fucich says. “The first commercial proof of concept of our Aerium Living Technology on display at the Pittsburgh International Airport.” This Aerium installation has the power of over 5,000 plants.

For Fucich, “the future involves further incorporating microalgae into architecture.” This means that for green design to be truly green, we’ll need to incorporate living technology into our built environment. If ecology teaches us anything, it is that the tiniest of single-cell organisms can influence the health of the most complex life, including us.