The average American spends 93% of their life indoors, according to the Environmental Protection Agency (EPA). Whether at home, work, or in an automobile, most of us spend the majority of our time in an enclosed environment. This is problematic for many reasons. The EPA’s Internal Air Study found that indoor concentrations of some pollutants are often two to five times higher than typical outdoor concentrations. People often attribute colds and flus to weather conditions, but in fact, we get colds and flus because we are indoors and are exposed to higher concentrations of airborne pollutants including cold and flu viruses. Alternatively, being outside is highly linked to a better mood and a better outlook on life.
Even if we wanted to spend all of our time outdoors, the reality is that most of us have indoor jobs with little flexibility to spend much time outside of our cubicle. While it is still important to get some daily outdoor exposure (the EPA recommends at least 5 minutes a day), adding plants to your indoor space can help purify your indoor environment.
During the late 1970s, when the energy crunch was being felt at both the gas pump and in heating and cooling costs, buildings were being designed to maximize energy efficiency to help alleviate spiraling energy costs. Two of the design changes that improved energy efficiency included superinsulation and reduced fresh air exchange. However, upon occupation of these buildings, the workers began to complain of various health problems such as itchy eyes, skin rashes, drowsiness, respiratory and sinus congestion, headaches, and other allergy-related symptoms. It was determined that the airtight sealing of buildings contributed significantly to the worker’s health problems. Similarly, synthetic building materials have been linked to numerous health complaints. The office equipment and furnishings placed in these buildings are also a contributing factor because of the types of materials used in their manufacture and design.
Humans are another source of indoor air pollution, especially when living in a closed, poorly ventilated area. This becomes apparent when a large number of people are present in a confined place such as an airplane for an extended period of time.
All of these factors collectively contribute to a phenomenon called, “sick building syndrome.” The EPA estimated that approximately 30% of all new or remodeled buildings have varying degrees of indoor air pollution. Energy-efficient buildings that are filled with modern furnishings and high-tech equipment off-gas hundreds of volatile organics which possibly interact with each other. Even at concentrations below present detection limits, some of these chemicals and reactive byproducts may adversely affect inhabitants of these buildings.
Symptoms of “sick building syndrome” are minimal in naturally ventilated buildings, which contain the highest level of microorganisms. On the other hand, the highest levels of symptoms are found in mechanically ventilated buildings containing low levels of microorganisms.
The brilliant minds at NASA have been studying indoor air pollution problems associated with sealed space habitats for over four decades. They found that a simple houseplant can combat indoor air pollution. Man’s existence on Earth depends upon a life support system involving an intricate relationship with plants and their associated microorganisms. The leaves, roots, soil, and associated microorganisms of plants aid in the removal of high concentrations of indoor air pollutants such as cigarette smoke, organic solvents/chemicals, pathogenic organisms/viruses/bacteria, and radon. The plant absorbs these air pollutants and converts them into new plant tissue.
Common Indoor Air Pollutants
Benzene is a very commonly used solvent and is also present in many basic items including gasoline, inks, oils, paints, plastics, rubber, detergents, pharmaceuticals and dyes. Benzene has long been known to irritate the skin and eyes and has been shown to be mutagenic to bacterial cells. Evidence also exists that benzene may be a contributing factor to chromosomal aberrations and leukemia in humans. Repeated skin contact with benzene causes drying, inflammation, blistering, and dermatitis. Acute inhalation of high levels of benzene has been reported to cause dizziness, weakness, euphoria, headache, nausea, blurred vision, respiratory diseases, tremors, irregular heartbeat, liver and kidney damage, paralysis, and unconsciousness. In animal tests, inhalation of benzene led to cataract formation and diseases of the blood and lymphatic systems. Chronic exposure to even relatively low levels causes headaches, loss of appetite, drowsiness, nervousness, psychological disturbances, and diseases of the blood system, including anemia and bone marrow disease.
Trichloroethylene (TCE) is a commercial product used in the metal degreasing and dry-cleaning industries, but it is also used in printing inks, paints, lacquers, varnishes, and adhesives. The National Cancer Institute considers this chemical a potent liver carcinogen.
Formaldehyde is a ubiquitous chemical found in virtually all indoor environments. The major sources, which have been reported and publicized, include urea-formaldehyde foam insulation (UFFI) and particleboard or pressed-wood products. Consumer paper products, including grocery bags, waxed papers, facial tissues, and paper towels, are treated with urea- formaldehyde (UF) resins. Many common household cleaning agents contain formaldehyde. UF resins are used as stiffeners, wrinkle resisters, water repellants, fire retardants, and adhesive binders in floor covering, carpet backing, and permanent-press clothes. Other sources of formaldehyde include cigarette smoke and heating and cooking fuels such as natural gas and kerosene.
Formaldehyde irritates the mucous membranes of the eyes, nose, and throat. It is a highly reactive chemical that combines with protein and can cause allergic contact dermatitis. The most widely reported symptoms from exposure to high levels of this chemical include irritation of the upper respiratory tract and eyes and headaches. The EPA’s research indicates that formaldehyde is strongly suspected of causing a rare type of throat cancer in long-term occupants of mobile homes.
Ammonia is a chemical found in window cleaners, floor waxes, smelling salts, and fertilizers. Symptoms associated with short-term exposure include eye irritation, coughing, and sore throat.
Best Air-Filtering Plants
Here are 18 air-filtering houseplants recommended by NASA to help keep your indoor environment clean and healthy!
PLEASE NOTE: SEVERAL OF THESE PLANTS ARE KNOWN TO BE TOXIC TO CATS, DOGS, AND OTHER PETS. IF YOU ARE A PET OWNER, PLEASE CHECK THE TOXICITY OF PLANTS BEFORE INTRODUCING THEM TO YOUR HOME.