The Truth About Houseplants: They Don't Make Indoor Air Clean
Some scientists at the United States National Air and Space Agency (NASA), looking for ways to cleanse the air in hermetically sealed space capsules, have touted houseplants as indoor air cleaners. However, environmental experts advise that more research is needed before you pin your hopes for fresher indoor air on your leafy friends. The air-cleansing theory tells us that during the photosynthesis process, plants remove carbon dioxide from the air and return all-important oxygen and water vapor to it. In recent years, environmental scientists have suggested that many plants may also remove harmful gases from indoor air. Some gases are absorbed through tiny pores in the leaves, called stomata, during the course of the plants' respiration cycle. Others are soaked up by the plants' roots and the moist soil in the pot. As a result, plants could be valuable in cleansing the air in newer houses and office complexes because modern construction techniques have created tightly sealed, superinsulated structures that can trap pollutants, such as formaldehyde, benzene, trichloroethylene, and ammonia, inside the home or office.
NASA scientists concluded that some plants work better than others. Areca palms, bamboo palms, lady palms, and dwarf date palms earned high marks. Rubber plants were good at ridding the air of formaldehyde. Spider plants did an excellent job of removing formaldehyde and carbon monoxide. Several dracaenas effectively filtered trichloroethylene from the air. English ivies, Boston ferns, philodendrons, gerbera daisies, pothos, spathiphyllum, Chinese evergreens, and chrysanthemums also stood out as top-notch air purifiers.
But despite NASA's promising results, the U.S. Environmental Protection Agency has called for more tests, ones that better simulate the home environment rather than the conditions inside a hermetically sealed space capsule. Test results so far indicate that a well-functioning ventilation system cleanses indoor air in a modern home or office building more effectively than even a roomful of plants.
Bringing plants indoors means bringing some health risks into your home. The damp soil plants grow in can harbor mold and other microorganisms that may be irritating, particularly to those with allergies. Plant leaves are magnets for dust, a major respiratory irritant. What's more, using a pesticide to control insects contributes to indoor air pollution. And some plants are toxic.
Instead of using pesticides indoors for infestations of aphids, mealybugs, mites, and whiteflies, spray plants with a soap solution (3 tablespoons liquid soap to 1 gallon/4 liters of water). To reduce dust buildup, wash or wipe off plant leaves once a week - more often if the leaves are major dust magnets.
Tags: NASA , Houseplant , Air , Plants
