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Air pollution outside is easy to spot, hanging over the city, or sputtering¹ from a tailpipe. But there's lot of indoor air pollution, too, even if it's not as obvious. It's caused by volatile² organic compounds, or VOCs. 

"They can come from building materials like paints, carpet, adhesives³, vinyl floors, varnishes⁴, solvents⁵, etc." Vadoud Niri, an analytical⁶ chemist at the State University of New York, Oswego. "And also they can come from home and personal care products, cleaning chemicals, air freshener, cosmetics⁷." 

And that cosmetics part… is what caught Niri's attention. "One day when I went to a nail salon⁸ with my wife, I noticed the smell of, specifically, acetone in there. And since I was doing air analysis at that time, I thought maybe we can do something about this." Acetone can irritate your eyes, skin, nose and throat and at high concentrations can cause nausea⁹, headaches and other nervous system problems.

Niri figured one way to get rid of acetone might be with houseplants. So he reviewed decades of literature in the field of plants as environmental cleanup agents—which is called biofiltration or phytoremediation. He then ran his own experiment, using an airtight chamber¹⁰, eight VOCs, in concentrations similar to those found in nail salons¹¹, and five common houseplants: a jade¹² plant, a spider plant, a bromeliad, a Caribbean tree cactus¹³, and what’s known as a Dracaena plant. 

Turns out, after a twelve-hour test, it was the bromeliad that scrubbed the most chemicals from the air. But as for his original quest, removing acetone from nail salons? The Dracaena beat out the others, sucking up 94 percent of the offensive compound. He presented the results at a meeting of the American Chemical Society, in Philadelphia. [Vadoud Niri et al., Monitoring volatile organic compound removal by common indoor plants using solid phase microextraction and gas chromatography-mass spectrometry]

Niri hasn't worked out all the details on the nail salon solution yet—that's next. But for a house or apartment, he says, "use a variety of plants to make sure you take all types of VOCs from your indoor air." Plus, they're an energy-free alternative to other air cleaning devices. In other words, a truly green solution.

—Christopher Intagliata