THE BEST HOUSEPLANTS FOR A HEALTHIER HOME
Whether it’s old or new, your home could be harboring unhealthy (and invisible) toxins. The world we live in is full of synthetic chemicals, most of which are toxic. These chemical compounds are found in emissions from paint, plastics, carpet, cleaning solutions, furniture, construction materials, and numerous building materials. Older homes might have toxic lead paint, asbestos insulation or tape, uffi, vermiculate insulation, in addition to other toxic chemicals from the building material and furnishings. Modern homes and buildings, designed for energy efficiency, are often tightly sealed to impede energy loss from heating and air conditioning systems. The ventilated air inside buildings recycles all kinds of solvents, including formaldehyde (an extremely toxic chemical). Synthetic building materials used in modern construction have been found to release potential pollutants that remain trapped in these unventilated buildings. Carpets aggravate the situation as they absorb many solvents which afterwards are released gradually over long periods of time. All this cause "Sick Building Syndrome". "Mild" effects of our daily exposure to these chemicals can be fatigue, disorientation, muscular pain, joint pain, eczemas, eruptions, dizziness, somnolence, nausea, body swelling, accelerated breathing, flue symptoms, asthma, palpitations, high pulse, sinusitis, anxiety, pneumonia, headache, memory loss, decreased focusing capacity, insomnia, irregular heart rhythm, gut issues and mood disorders (depression and mood swings). On long term, this exposure can seriously stress immune system and is believed that can cause cancers. How seriously we are affected by this is influenced by the severity of the overal toxins and chemicals absorbed, duration of exposure, our overall health, age, excercize habits, and mood (which also influence immunity), medical history and lifestyle choices (eating, drinking, smoking, medical/recreational drug consumption...).
Three major offenders found in the home include:
formaldehyde: in carpets, upholstery, glues, paint, and more
benzene: in plastics, synthetic fibers, lubricants, rubber, pesticides, and more)
trichloroethylene: in paint removers, rug cleaning solution, adhesives, and more
Nature has a way of keeping itself clean. 2-year NASA research points to an unexpected, cost-effective, environmentally friendly, low energy and completely natural method of detoxifying homes with common indoor household plants. NASA aimed to assess environmental issues, both on Earth and in space habitats, and this new study has been led by Dr. Bill Wolverton, formerly a senior research scientist at NASA's John C. Stennis Space Center, Bay St. Louis, Miss. There are many powerful air-cleaning plants that naturally remove pollutants from the air. Having good indoor air quality is very important, especially since many of us spend so much time inside. NASA did a study to find out which plants were best to filter the air of the space station, and their findings are available to all. Some house plants are better then others to filter the air (not only producing Oxygen from CO2, but also absorbing benzene, formaldehyde and/or trichloroethylene... and other toxins.) Plants (more specifically the leaves) have been known to function like air pumps.
19 species and varieties of ornamental plants have been tested for their effectiveness in removing the main toxins connected to indoor air contamination. 17 are true houseplants, and 2 species of daisies are used indoors as seasonal decorations. The houseplants are tropical or subtropical species growing beneath dense tropical canopies, thus they subsist in low light, and are more efficient in absorbing gases, including toxic ones. Plants do not absorb contaminants only trough leaves, but also through roots and their root-associated bacteria.
Some indoor plants proved to be so efficient in absorbing the air toxins that some could be launched into space integrated in biological life support systems aboard future orbiting space stations. "The study has shown that common indoor landscaping plants can remove certain pollutants from the indoor environment. We feel that future results will provide an even stronger argument that common indoor landscaping plants can be a very effective part of a system used to provide pollution free homes and work places, "said Wolverton, involved in this kind of research for over 30 years.
Each plant species was tested in sealed, Plexiglas chambers in which chemicals were injected. Tested chemicals included:
1. Trichloroethylene (TCE), largely employed in the metal degreasing and dry cleaning industries, printing inks, paints, lacquers, varnishes, and adhesives. It is a powerful liver cancer inducing factor. The best TCE removers were peace lily (for TCE from cleaning products), Dracaena (TCE from adhesives, ink, dyes, lacquers, paints and varnishes), gerbera daisy (TCE from adhesives), and bamboo palm.
2. Benzene is the most common solvent in many items like gasoline, inks, oils, paints, plastics, and rubber, but it also enters into the composition of detergents, explosives, pharmaceuticals, foams and dyes. It is a skin and eyes irritant (repeated contact causes drying, inflammation, blistering and dermatitis), embryotoxic and cancer causing factor. It has been connected to human leukemia. The aromatic benzene vapors cause dizziness, weakness, euphoria, headache, nausea, blurred vision, respiratory diseases, tremors, irregular heartbeat, liver and kidney damage, paralysis and unconsciousness. Animal tests resulted in cataract formation and diseases of the blood and lymph. Chronic exposure provokes headaches, loss of appetite, drowsiness, nervousness, psychological issues and blood diseases (like anemia) and bone marrow diseases. The champion plants in removing benzene appeared to be: ivy, gerbera daisies, pot mums, peace lily, bamboo palm, and Mother-in-law's Tongue. The source of benzene also counted: Chinese Evergreens and pot mums extract well benzene coming from detergents, while Dracaena that coming from ink, dyes, tobacco smoke and rubber. Ivy extracted easily the toxins coming from petroleum products, while benzene from plastics was rapidly sucked up by Gerbera daisy.
3. Formaldehyde is even more common than benzene, and more toxic. It abounds in urea-formaldehyde foams, particle board or pressed wood products of which most of the office furniture is made today. It appears in paper treated with UF resins, even grocery bags, waxed papers, facial tissues and paper towels. Most common household cleaning agents have formaldehyde. UF resins are used as stiffeners, wrinkle resisters, water repellents, fire retardants and adhesive binders in floor coverings, carpets and permanent-press clothes, while simple formaldehyde abounds in natural gas, kerosene, and cigarette smoke. Research shows the chemical is an irritant of the mucosae of the eyes, nose and throat, and causes dermatitis and headaches. Formaldehyde is a common cause of asthma and has been connected to throat cancer. The best plants for removing formaldehyde proved to be the bamboo palm (from carpeting), Mother-in-law's tongue (from paper), dracaena warneckei, peace lily, dracaena marginata, golden pothos, philodendron (from carpeting and furniture), ficus (from UF foams), ivy (from cleaners) and green spider plant (from plywoods and particle boards).
This is how much of the contaminants were removed by plants from a sealed room in 24 hours:
Formaldehyde % Benzene % Trichloroethylene %
Dracaena massangeana 70 21.4 12.5
Dracaena deremensis 50 70 20
Ficus Benjamina 47.4 30 10.5
Spathiphyllum 50 80 23
Epipremnum aureus 67 67 9.2
Chrysanthemum morifolium 61 53 41
The plants recommended by the NASA research are:
1. Philodendron scandens subsp oxycardium heartleaf philodendron (philodendrons come from tropical Americas and are related to arrowheads).
2. Philodendron domesticum, elephant ear philodendron.
3. Dracaena fragrans, varieties `Massangeana', `Janet Craig' and `Warneckii', cornstalk Dracaena, happy plant or Corn Plant, a relative of dragon trees from Africa.
4. Hedera helix, common ivy, which is also an outdoor plant originated from southern Europe.
5. Chlorophytum comosum, spider plant, a South African species.
6. Ficus benjamina, weeping fig tree, from southeastern Asia and Australia.
7. Epipremnum aureum, golden pothos, silver vine, devil's ivy, is a species coming from southeastern Asia and New Guinea, related to philodendrons.
8. Spathiphyllum x `Mauna Loa', a peace lily hydrid obtained from tropical American and Asian species.
9. Philodendron bipinnatifidum cut-leaf philodendron, tree philodendron, selloum, self-header from the rain forests of Paraguay and southeastern Brazil.
10. Aglaonema modestum, Chinese evergreen from southern China, related to philodendrons.
11. Chamaedorea sefritzii, bamboo or reed palm, a palm tree species originated from tropical Americas.
12. Sansevieria trifasciata, snake plant or mother-in-law's tongue, an African plant related to Butcher's broom.
13. Dracaena marginata , red-edged dracaena or Madagascar dragon tree.
14. Gerbera jamesonii, Gerbera daisy, from South Africa.
15. Chrysanthemum x morifolium, pot mums, a hybrid daisy from Asia.
As plants have various ecologies, their efficiency varied depending on the light amount. The best plants in intense light were the Ficus and some Dieffenbachia species. In medium light, were Bamboo Palm and Dracaena. In low light, Spathiphyllum worked best.
"Research in our laboratories has determined that plant leaves, roots and soil bacteria are all important in removing trace levels of toxic vapors. Combining nature with technology can increase the effectiveness of plants in removing air pollutants. A living air cleaner is created by combining activated carbon and a fan with a potted plant. The roots of the plant grow right in the carbon and slowly degrade the chemicals absorbed there," said Wolverton.
The results recommend for an average home of under 2,000 square ft (200 square meters) 15 to 18 houseplants, grown in 6 in (15 cm) containers or larger. The more vigorous the plants, the better. "Two plants per 100 square feet or two plants per a small office keep the air pure [and] healthy," recommended Wolverton. These plants can not only make your office or house a more pleasant place, but also they can increase air quality, helping you feel better. Further research is aimed to see the efficacy of indoor plants in removing other common indoor air pollutants, like asbestos; or coming from pesticides, detergents, solvents, and cleaning fluids; fibers released from clothing, furnishings, draperies, glass, carpets, and insulation; fungi and bacteria; and tobacco smoke.
Books by Dr. B.C. Bill Wolverton: