A Living Air Filter

These filters use plants and fans to clear the air of toxic chemicals

By Lauren Aaronson Posted 05.13.2008 at 12:30 pm 9 Comments

OBJECT D’ART Mathieu LeHanneur at the Museum of Modern Art in New York, where his plant-based air filter is on display. John B. Carnett

Bel-Air
Cost to Develop: $236,000
Time: 1 year
Prototype | | | | | Product
Your home could be emitting toxic gases. Just ask the victims of Hurricane Katrina, whose emergency trailers, made with glue-laden particleboard, let off so much formaldehyde that the Centers for Disease Control and Prevention warned that residents should “spend time outdoors” and “make relocating to permanent housing a priority.” Even in more expensive new homes, the concentration of emissions from things like furniture, carpet and paint can be two to five times as high as it is outdoors. But most air filters only catch particulates such as dust and pollen rather than organic compounds like formaldehyde and benzene, and the filters that do trap those gases need frequent replacement. So Mathieu LeHanneur and David Edwards built an ultra-efficient filtration system that eliminates toxins using nature’s own hazmat squad: plants.

How the Bel-Air Works: To increase efficiency, fans in the Bel-Air circulate air in complex patterns around the plant’s leaves and force air through the roots and soil.

The duo, a French product designer and a Harvard University biomedical engineer, unearthed NASA research from the 1980s on plants that absorb chemicals through their leaves and roots. Philodendra, for instance, soak up formaldehyde much as they do carbon dioxide. But plants can clean only the air that touches them. To quickly and efficiently clean a whole room, LeHanneur constructed a container that moves as much air as possible around the entire plant. A fan blows breezes around the leaves, and a second fan sucks air through a hole in the soil. Microbes on the plant’s roots metabolize more toxins than the leaves do, and the soil works like a traditional charcoal filter to capture even more. Underneath the soil, a tray of water produces humidity that keeps the plant moist and traps additional toxic molecules. A vent on the side releases fresh air into the room. In early trials, the device reduced a test chamber’s formaldehyde concentration by 80 percent in one hour.

LeHanneur and Edwards built the Bel-Air for an exhibit at Le Laboratoire, a gallery in Paris that features collaborations between scientists and artists. The next step could be pairing with a company to adjust the design for manufacturing. Michael Braungart, an environmental chemist at the University of Lüneberg in Germany, says it’s a creative application of real science: “It uses the best of nature combined with the best that human beings can do.”

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9 Comments

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mcjagger

05/13/08 at 4:11 pm

I think this air filter is a good idea, because there are a lot of people out there who have breathing problems or just want cleaner air. And it's NATURAL

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redwarrior

05/14/08 at 7:40 pm

I love the idea, but i see problems with plant growth in a contained space. Im also not sure why a larger house plant in a pot with a household fan wouldnt have a similar effect?

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Alex R.

05/16/08 at 6:00 pm

Better yet, get rid of any unnecessary pollutants and open the windows when possible.

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mikeymoran

05/26/08 at 2:16 pm

re: "I'm also not sure why a larger house plant in a pot with a household fan wouldnt have a similar effect?"

it WOULD have a similar effect. but nobody is going to put a houseplant with a household fan in the Museum of Modern Art. people have to have something to make it worth "having" whether it's gimmicky or not, and it sure helps if it is good to look at, and a plant and a fan wouldn't really complete with a groovy looking object.

but when we get carpeting installed in our new upstairs, i'm gonna load it up with plants and fans to eat up all the fumes.

if i were a carpet installer, i'd have a collection of rhodendrons and fans to loan out to new customers for a week after installation. yes, you're admitting your carpets carry toxins, but maybe you'd get points for honesty. and those plants are hard to kill.

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harry ru

05/28/08 at 8:55 pm

i think the plants are not borned to absorb these toxic gases which will kill these plants when the absobed gases reaching to a certain concentration,and thera primary task is going on photosynthesis to produce carbonhydrates to support their life.and i think the pots also can not afford enough lmusted iving conditions to plant.i think it will be a complexed problem and will be not convenient.

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KPeters

05/29/08 at 9:21 am

I believe the filter brings the air through both the plant area, the roots and the liquid in the soil. Sort of like three filters instead of just having go by the leaves.

I see positives because, let's face it, opening the window to fresh air anywhere close to a city or plant is a misnomer.

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phpadmin

06/05/08 at 3:51 pm

good idea. thanks

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phpadmin

06/05/08 at 3:53 pm

good idea. thanks

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Timelord

07/25/08 at 10:02 am

I remember reading articles in Popular Science in the 80s about this concept. Bill Wolverton came up with the concept to clean air in spacecraft. He even had the idea to have a fan suck air through the soil, where microbes could help degrade the chemicals. Harry Ru, the plants don't just absorb toxins and die. They break down the chemicals. The only thing this product does is try to package everything in a neat container, which doesn't make it a new or ingenious invention, just decent product design.