The ABCs of VOCs
Volatile organic compounds (VOCs) and outgassing don't sound like terms in the average homeowner's vernacular, but they should be. These chemicals - VOCs - could be affecting the health of some or all of the people in your home. Because there is no government agency charged with regulating these substances in particular or indoor air quality in general, homeowners must educate themselves about the effects of these gases on their health. That is the first step in a personally beneficial education process. Start by noting that the U.S. Environmental Protection Agency has been mandated to study indoor air quality. The agency provides information, but it does not regulate indoor air.
The federal Department of Housing and Urban Development (HUD) provides information mainly about problems with lead paint in existing houses. The U.S. Consumer Product Safety Commission provides information about products that are not part of the structure of the house. But before people are overwhelmed by the thought of dealing with another threat, they should know that there is good news: There are sources of information from people who have studied how to build healthier houses and where to find materials that have fewer or none of those nasty VOCs. These sources say healthy building materials and practices are available in a variety of forms. Even unhealthy materials can be used for many people, if the material is separated from the interior parts of the house during its outgassing stage. "It only takes a little more time, planning and money - but not much - to build a healthy house instead of one that could put people at risk," says John Bower, co-founder of the Healthy House Institute (www.hhinst.com), along with his wife, and author of several books on dealing with unhealthy materials and unhealthy homes. But before they start on what can become an involved but helpful process, people need to understand both the short- and long-term effects of unhealthy materials that emit VOCs. Health effects from indoor air pollutants like VOCs may be experienced soon after exposure or possibly years later, according to the EPA (www.epa.gov/iaq). Immediate effects may show up after single or repeated exposures.
These include irritation of the eyes, nose and throat, headaches, dizziness, and fatigue. Such immediate effects are usually short-term and treatable, the EPA indicates. Sometimes the treatment is simply eliminating the person's exposure to the source of the pollution, if it can be identified. Symptoms of some diseases, such as asthma, may also show up soon after exposure to some indoor air pollutants, the federal agency says. The likelihood of immediate reactions to indoor air pollutants depends on several factors. Age and pre-existing medical conditions are two important influences. In other cases, whether a person reacts to a pollutant depends on individual sensitivity, which the EPA says varies tremendously from person to person. The agency says it appears that some people can become sensitive to chemical pollutants. But the immediate effects may be similar to those from colds or other viral diseases, so it is often difficult for a doctor, pharmacist or the individual sufferer to determine if the symptoms are the result of exposure to indoor air pollution. For this reason, it is important to pay attention to the time and place symptoms occur. If the symptoms fade or go away when a person is away from home or their normal routine, for example, an effort should be made to identify the sources in the home, auto or workplace that may be possible causes.
Other health effects may show up years after exposure or only after long or repeated periods of exposure. These effects, which include some respiratory diseases, heart disease and cancer, can be severely debilitating or fatal, according to the EPA. So the federal agency says it is prudent to try to improve the indoor air quality in a home, even if the symptoms are not yet noticeable. While pollutants commonly found in indoor air are responsible for many harmful effects, the EPA says there is considerable uncertainty about what concentrations or periods of exposure are necessary to produce specific health problems. The agency says further research is needed to better understand which health effects occur after exposure to the average pollutant concentrations found in homes and which occur from the higher concentrations that occur for short periods of time. Research by the Health House program (www.healthhouse.org) of the American Lung Association indicates that with an estimated 36 million Americans suffering from allergies or asthma, IAQ concerns have become more prevalent. Many possible triggers are found inside the home, including such volatile organic compounds as benzene, toluene, formaldehyde and ethanol. The ALA notes that the EPA's Total Exposure Assessment Methodology (TEAM) studies have found levels of common organic compounds to be two to five times higher inside than those found outside. Health House says growing evidence suggests that some homes may be detrimental to the health of their occupants, especially those with compromised lung function due to age, asthma, chemical sensitivities or other respiratory conditions. The Health House Rx program provides educational programs, materials and services to help consumers address this growing national problem. Due to energy-conscious construction practices, homes have become tighter in the past few decades, resulting in reduced ventilation and a possible increase in pollutants. To combat this growing trend, Health House Rx provides materials and services to help consumers evaluate the environment in their homes. Health House also provides training for homebuilders. The first step in the process is identifying home environment problems.
The Health House program suggests that people ask the following three questions about problem areas they identify to determine if they need to have their home evaluated by a professional. 1) Do I perceive the problem to be an immediate health concern for occupants of my home? 2) Are any occupants at high risk because of asthma, compromised immune systems, allergies, chemical sensitivities or respiratory problems? 3) Are there problems in several areas of the house that might indicate a need to check out underlying causes or a recurring problem? A builder who has studied the situation says at the top of the list of indoor air pollutants are the most common offenders in new homes - VOCs. Most building materials release into the air, (or outgas) the chemicals from which they are made, some in quite high concentrations after their manufacture, and often at lower levels for years later, according to Barbara Harwood, a homebuilder, a chemically sensitive person and author of The Healing House (email@example.com). Those materials that outgas the most should be avoided in building. "The one we watch for most closely as builders of healing homes is urea-formaldehyde, perhaps the most common and problematic VOC used in building materials and a potent mucous-membrane irritant." She says this is the chemical that burns your nose when you walk into a fabric store, because most new fabrics are treated with it for color and texture retention. It also outgasses from new furniture and automobiles. Formaldehyde is the acidic, slightly irritating smell of many newly installed carpets, glues and wall fabrics. Upwards of 5 billion pounds of the chemical are manufactured in this country alone every year.
About half of that quantity is used for materials that go into buildings, such as particleboard, plywood, cabinets and fiberglass insulations. "The problem with the chemical comes primarily when it is trapped inside a space where living things need to breathe, particularly any living being who is sensitive to it," Harwood explains. She became hypersensitive to it during her college days in a poorly vented zoology lab with high exposures. "I actually became physically debilitated by the intensity of the headaches, which made me dizzy and nauseous and eventually created visual problems. I switched my major, and the next day, the headaches went away. However, those years of exposure did make me hypersensitive to formaldehyde. So needless to say, when someone tells me they get headaches from the smell in new homes, I'm completely sympathetic." After doing some research on building materials a few years ago when a customer came to her with multiple chemical sensitivities (MCS), Harwood says she began to realize that nobody, MCS or not, needed to be breathing this stuff. "At that point, my company started consciously eliminating as many VOCs from our homes as possible." Harwood notes that MCS is still a subject of debate among medical experts and people who aren't troubled by this problem. People who have it and experience the symptoms when they are in the presence of offensive chemicals, but not at other times, have no doubt that it is the chemicals causing the problem. "So first, please understand that you could be at risk even if you are not aware that you have chemical sensitivities," Harwood says. "There is a group of people in between those who are chemically sensitive and those who have no problem with any chemicals for whom the distinction is more subtle." She says chemical sensitivity has been recognized by occupational physicians for decades.
The physical mechanism causing it may be similar to the one that causes hay fever. "Just as some people with allergies sneeze while others suffer life-threatening anaphylactic shock, so people's reactions to chemicals vary widely." The first VOC that builders can avoid, in addition to urea-formaldehyde, is probably also one of the most annoying to people moving in immediately after a home is completed: paint fumes. Harwood says its smell gives many people headaches. She notes that now it is possible to buy paints that are virtually VOC free. "We had an exhibit at a home show of two kinds of paint - one regular paint and one low-VOC paint. People could tell a significant difference in our informal smell test, and a comment was made that the low-VOC paint smelled like a milkshake." But the list of VOCs goes far beyond paint and formaldehyde. Many people are under the impression that the two substances are the cause of the majority of IAQ complaints. They are often surprised to learn that there are hundreds of different volatile organic chemicals polluting indoor air. Most of the modern materials created in the last 50 years outgas to some degree. Most synthetic carpeting, adhesives, kitchen cabinets and wall paneling have been implicated, according to Bower of the Healthy House Institute. The outgassing is a universal component of indoor air pollution, and it can result in sinus and lung irritation. He says that some of the chemicals released can damage the immune system. "The interior products are almost always the most significant outgassing sources, rather than the things that aren't directly exposed to the living space - insulation, framing, roofing. That doesn't mean roofing, siding and insulation can't be a problem. It's just that they aren't the most likely culprits."
Many interior materials can absorb then re-emit various VOCs, Bower explains. This is called the sink effect, and because of it, you can remove a material that has been outgassing VOCs into the indoor air, and still have VOCs present because they were stored and released by other materials. Re-emissions from sink materials can result in longer exposure than would occur in the absence of sinks. Carpet, draperies, furnishings, wood and gypsum wallboard all act as sinks. Bower says one study found that carpet and drywall acted as sinks for specific VOCs found in latex paint and that the VOCs were released very slowly, at very low rates. The best method for controlling formaldehyde, paints and most other pollutants involves actually removing the source from the house. This can be quite expensive if the source is insulation, kitchen cabinets or particleboard subflooring. (Editor's note: Particleboard is rarely used as a subflooring material anymore, but it is often confused with oriented strand board (OSB), which is the material of choice today. The Engineered Wood Association recommends OSB for many structural uses and certifies that it is not a significant source of harmful outgassing.) To avoid those products in a newly constructed house would also be quite expensive. An extremely healthy house certainly involves a host of inert materials, such as steel framing instead of wood, walls of porcelain panels, custom-made cabinetry and special insulation. Bower adds that a complicated air-filtration system would be necessary to keep the indoor air pristine. While such a house may be necessary for some remarkably sensitive people, most average, healthy people do not require a house built to such extreme standards, according to Bower. "So, a person in reasonably good health may opt for some compromises. After all, a healthy immune system should be able to deal with minor levels of pollution.
By making a few compromises, a reasonably healthy house, a generically healthy house, can be built at a modest increase in cost - sometimes at no increase." The range of cost increase would be from 0 to 25 percent more than a conventional house, depending on such factors as the particular materials chosen, the geographic part of the country and the size of the project, according to Bower. Another factor is that specialized healthy construction products may not be available locally. Furthermore, builders and architects may not want to work with unfamiliar materials, so the cost may be too high. To help people gain access to healthy materials and suppliers, there are now websites listed for most of the over 600 companies found in the resource section of Bower's book, The Healthy House: How to Buy One, How to Build One, How to Cure a Sick One. Plus, there are over 1,300 reference notes to help people track down more in-depth information or technical research papers.
Dan McLeister is a freelance writer based in Carol Stream, Ill.