Indoor Air Pollution & Plants

In our world of energy efficient houses and office buildings sealed against the elements, it is alarming to find the number of pollutants that are constant roommates. Copy machines and printers, rug pads, insulation and other synthetic materials, veneer furniture, products made of pressed wood and plywood, smoke, and detergents all give off pollutants, such as benzene, trichloroethylene, xylene, ammonia and formaldehyde. Studies by the EPA (Environmental Protection Agency) indicate that indoor air pollution is one of the fastest growing environmental problems.

How can we reduce these troubling substances in our lives? Plants reduce indoor pollution and therefore provide us with a healthier physical atmosphere. They absorb pollutants through their leaves, where naturally occurring microorganisms break down the chemicals. Some absorption and breakdown also occurs in potting soil.

The original research on plant filtering began with NASA, where the need to find ways to reduce the high amount of pollutants emitted by equipment on the space shuttle was discovered. Researchers as the National Space Technology Lab found that houseplants reduced pollutants, particularly nitrogen and formaldehyde. In fact, just a single spider plant in an enclosed chamber filled with formaldehyde removed 85 percent of the pollutant in a day. As few as 15 plants can significantly reduce pollutants in the average house. The study suggested that we use one potted plant for every 100 square feet of floor space for pollution control.

Besides controlling gaseous pollution in the home, plant leaves clean air by trapping particulate matter. And, in their natural process of respiration, plants absorb our waste product ~ carbon dioxide ~ and furnish us oxygen and moisture. The old myth about avoiding plants in the bedroom because they use up air couldn't be further from the truth.


Common Sources of Indoor Air Pollution & The Best Absorbers:

Formaldehyde:
Carpeting, pressed wood, fiberboard, foam insulation, paper products
Best Absorbers:
Bamboo Palm, Dracaena, Golden Pothos, Philodendron, Sansevieria, Spider plant

Hydrocarbons:
Vynl furniture, detergents, fabric softener
Best Absorber: Spider plant

Nitrogen Dioxide:
Malfunctioning furnaces, water heaters, leaking chimneys
Best Absorber: Spider plant

Benzene:
Glue, spot remover, paint, varnish, paint stripper
Best Absorbers: Dracaena, English Ivy, Spathiphyllum

Methylene Chloride:
Paint stripper, aerosols
Best Absorber: Spider plant

Trichloroethylene:
Ink, paint, lacquer, varnish, adhesive
Best Absorbers: Dracaena, Spathiphyllum



Resources:

Indoor Web Ring ~ a ring of web pages dedicated to indoor growing.
Indoor Web Ring


Informative Further Reading:

The Royal Horticultural Society
Encyclopedia of House Plants
London: Century Publishing. 1987.

The Indoor Garden
John Brookes
New York: Crown Publishers. 1986.