Martha meets NASA

This is an excerpt from Yes! Magazine that I thought was so nifty I'd circulate widely. To subscribe or support their work, visit their website http://www.yesmagazine.org.

So, you’ve made the “green” energy-efficiency improvements to your home. Windows and doors are tightly sealed, and extra insulation keeps you in a comfy cocoon. But less drafty airflow can mean stale air at best, and toxic air at worst.

Here’s a “green” solution: houseplants.

Years ago, NASA scientists demonstrated that certain plants break apart the chemicals most commonly released by plastics, paints, synthetic carpets, and cleaning supplies.

Why are they such efficient air purifiers?

Most houseplants evolved in subtropical forests, where they received light filtered through the branches of taller trees. Because of this, their leaf composition allows them to photosynthesize under relatively low light conditions, which allows them to process gases efficiently. Soil and roots also play a role. Microorganisms in the soil become more adept at using these materials as a food source as they are exposed to them for longer periods of time. Their effectiveness is increased if lower leaves that cover the soil surface are removed so there is as much soil contact with the air as possible.

It takes about 16 houseplants in 6- to 8-inch diameter containers to improve air quality in a 1,800 square foot house. Some non-poisonous standouts from the NASA study: spider plant, golden pothos, peace lily, chinese evergreen, ficus, gerbera daisy, and rubber plant.

Various species were tested with trichloroethylene, used in dry cleaning, paints, lacquers, and adhesives; benzene, solvent in gasoline, paints, dyes, plastics, and foams; and formaldehyde, more common and more toxic, used in particle board, office furniture, household cleaners, fire retardants, and carpets.

This is how much of the contaminants were removed by plants from a sealed room in 24 hours:

Trichloroethylene Benzene Formaldehyde

Dracaena Massangeana
70% 21.4% 12.5%

Dracaena Deremensis
50 70 20
Ficus Benjamina
47.4 30 10.5
Peace Lily spacer
50 80 23
Golden Pothos
67 67 9.2
Chrysanthemum
61 53 41