Indoor Air Quality Controversy: Do Plants Clean the Air?

Indoor Air Quality Controversy: Do Plants Clean the Air?

Stephanie Kinnear
Dec 21, 2007

This one is almost as good as the old dishwasher debate.

We had always been told (and believed) that some plants have the ability to protect us from indoor air pollutants. We've never tested the theory out on our own -- we have cats who would turn their noses at a can of tuna for the opportunity to nibble on gerber daisies and potted plants -- but we believed it anyway.

Treehugger lists the top 5 plants for improving indoor air as: peace lily, bamboo palm, English ivy, mums, and gerbera daisies. OK. Sounds good to us -- but do they really clean the air?

The EPA doesn't think so. In an Indoor Air Quality FAQ, they answer the question, "Can plants control indoor air pollution?", like this: The only available study of the use of plants to control indoor air pollutants in an actual building could not determine any benefit from the use of plants. As a practical means of pollution control, the plant removal mechanisms appear to be inconsequential compared to common ventilation and air exchange rates. In other words, the ability of plants to actually improve indoor air quality is limited in comparison with provision of adequate ventilation.

They even go on to hint at the fact that damp planter soil could worsen indoor air quality.

Believers of plants' ability to improve indoor air quality point to a joint NASA / Associated Landscape Contracotrs of America (ALCA) study that calls low-light requiring houseplants (along with activated carbon plant filters) one of the most "promising means of alleviating the 'sick building syndrome' associated with many new, energy-efficient buildings."

Skeptics, however, claim these studies don't appropriately replicate real indoor environments.

We're partial to indoor plants, and would lean toward having them in our home (out of the cats' reach) on the off chance that they're even remotely capable of reducing our indoor pollution by the smallest fraction.

What do you think?

Image: Via wockerjabby;

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