Benefits of Living Plants
On April 8th & 9th Exotic Plants took part in The Green California Summit & Exposition. It was an exhibition of how we can be more conservation aware in our lives and businesses. I was asked to prepare an article for our booth on the benefits of having living plants in our homes and offices. Although I knew a little about this, I was really surprised by what i did find out.
Many of the visitors to our booth asked that we make this article available here, on our web site, so here it is.
In the late 1960s, Bill Wolverton, Ph.D., an environmental scientist, was working with the U.S. military to clear up the environmental messes left by biological warfare centers. In a test center in Florida, where a de-foliation herbicide called Agent Orange had entered the local waters through a nearby government test site at Elgin Air Force Base, he and his people discovered that swamp plants were actually eliminating Agent Orange. Agent Orange was a powerful de-foliant which was used by the U.S.A. in Vietnam during the Vietnam War.
This success behind him, he wanted to pursue this line of research and moved to the Mississippi Test Center, now known as NASA’s Stennis Space Center. Nasa funded him to look into Nature’s ability to cleanse itself, and into a closed system environment’s eco support with a view to helping design sustainable living quarters for space. He was given the task of cleaning the center’s waste water using plants. To this day, instead of a septic tank, the center still uses his system that employs water hyacinth plants.
By 1973, NASA had identified 107 volatile organic compounds, VOCs, in the Skylab space station. All synthetic materials that form our modern furnishings, and were also used in Skylab, exude low-level gases, known as off-gassing. When those chemicals, like benzene, formaldehyde, trichloroethylene, all potential carcinogens and irritants, are trapped in a closed environment such as Skylab, the inhabitants become ill.
Around this time, America had an energy crisis and offices and homes were being built to be more energy efficient, and thus more airtight. This, of course, reduced air circulation and that, combined with the use of modern building materials, caused the same effects as the Skylab astronauts were suffering from. Now called Sick Building Syndrome, it is caused when the toxins in the modern materials became trapped in the buildings because of the lack of air circulation.
Unsurprisingly, there are many volatile compounds used in the manufacture of our modern furniture, furnishings, and the technology we use daily. The volatiles are in adhesives, in carpeting, and even in the white correction fluid we use in offices. We cannot avoid these chemicals that form part of our daily lives.
The most common ones are listed below:
Benzene, used in solvents, detergents, oils, paints, synthetic fibers, plastics, and inks.
Trichloroethylene, used in printing inks, varnishes, lacquers, dry cleaning, and adhesives.
Carbon monoxide, found in fuel-fired furnaces, gas water heaters, fireplaces and wood stoves, gas stoves, and gas dryers.
Formaldehyde, used in plywood, particle board, carpeting, furniture, clothes, paper goods, and household cleaners.
What Wolverton discovered in his tests was that the plants produced water vapor that created a pumping action to pull contaminated air down to their roots. There the contaminants were converted into food as the plant’s root systems, and the soil bacteria, converted the VOS into a food source for the plants. The more air that circulated around the roots of the plant, the cleaner the air became.
Wolverton found that certain plants had an affinity with specific toxins and could remove them from the air more easily than others. Most of the plants effective in removing indoor air pollutants are not exotic and are readily available. They include English ivy, aloe vera, ficus benjamina, areca palm, bamboo palm, sansevieria, philodendrons, all of the draceneas but especially the Janet Craig, chrysanthemums, bromeliads and orchids. Orchids and bromeliads were found to be the only plants in his list that photosynthesize at night.
To get the best results, Wolverton used activated charcoal in the plant pot, then a fan to ensure good air circulation round the plants. The VOS are drawn into the charcoal to be utilized by the roots of the plant, and the soil bacteria, into a food source.
By 1990, Bill Wolverton had left NASA and had set up his own firm called Wolverton Environmental Services which is a small environmental consulting firm that is continuing his work in the cutting-edge field of phytoremediation. The Company advocates the use of plants and their root-associated microorganisms to biodegrade and treat indoor air and water pollution and has developed many systems for businesses and potentially for space exploration and permanent bases on the Moon or Mars.
You don't need to turn your home into a jungle to help clean the air in your home. Wolverton figures two to three 8-10" plants (container size) for every 100 square feet of floor space can do the job.
Of course, it goes without saying that you must look after the plants properly. A lot of plants could mean excessive humidity, which can contribute to the growth of mold and bacteria and can encourage unwanted pests. To prevent that, don´t let your plants sit in stagnant water. Apart from anything else, it’s a good way to kill your plant, plus the sour water will smell. Self watering planters, which have built-in watering tubes, avoid the problem altogether by routing water directly to a reservoir in the soil.
Wolverton cautions that plants should never be thought of as a cure-all. "If you have a new building with serious indoor air pollution, even a large number of plants isn´t going to solve the problem," he says. But a plant in your "personal breathing zone"– which Wolverton defines as the six to eight cubic feet of air surrounding an individual– can be a comforting presence.
"If you spend a lot of time at a computer or in an easy chair watching TV, try to have a nice plant sitting near you," he suggests. "Because the closer you are to that plant, the more it´s going to benefit you."
Bibliography
http://www.zone10.com/tech/NASA/Fyh.htm
http://www.sti.nasa.gov/tto/Spinoff2007/ps_3.html
http://www.wolvertonenvironmental.com/
http://www.nationalwildlife.org/nationalwildlife/article.cfm?issueID=16&articleID=220
Wolverton: How to Grow Fresh Air
Wolverton: Eco Friendly House Plants
