To limit opportunities for toxic outgassing that are characteristic of a sick home, some people build steel frame rather than wood frame houses.
PHOTO: JOHN BOWER
When Homo sapiens' predecessors paused to contemplate the threats around them, they looked outward. Whether they feared a lack of shelter from the weather, a simple shortage of food, or a large cat with a taste for human flesh, danger was "out there." Safety lay inward: toward the fire, behind the cave mouth, or inside the tent made of skins and mammoth bones. Arguably, our ongoing fascination with (and comfort in) home and hearth had such beginnings.
But for most of the earth's population, the rules of survival have changed dramatically in the last 10 or 20 millennia — changed much more rapidly than human social or genetic codes. Our ability to alter our environment has thoroughly outstripped our ability to adapt to it. As a result, we sometimes end up hobbled by our heritage. Our attitude toward our homes is a classic example. Despite the mounting evidence, we're slow to accept that under some circumstances home is not a sanctuary. Such is the case when a home becomes a sick home.
Between 5 million and 30 million Americans suffer from environmental illnesses brought on by barely discernible levels of a variety of toxins — chemical and biological — found in their own homes. Those numbers are startling, but even more alarming are estimates that only 5% of these so-called chemically sensitive people have recognized the source of their sickness and been treated for it. The numbers of the afflicted are burgeoning, yet neither the scientific/medical community nor the public has fully accepted just how much trouble can start at home.
Residential Toxins: Symptoms and Sources
Our Residential Toxins Chart is designed to help you pinpoint household toxins that might be causing the symptoms you or your family members are experiencing. The listings are far from exhaustive, but they do cover the most common symptoms and sources. Also bear in mind that some chemicals have been examined much more thoroughly than others, so many more symptoms and sources are known for them.
Start by writing down all the symptoms you've noticed. Then check through the ones on the chart to see if there's a toxin with a set of symptoms to match yours. You'll notice that many of the listed toxins can produce headaches, so you'll not be able to divine much from that symptom alone. Instead, look for a toxin that produces a pattern of symptoms similar to your own. Once you've found a candidate, move over to the far right, and see if you have a likely source for the pollutant in your home.
At this point, some recollection and analysis can be very helpful. Think about when symptoms started and whether there were any significant changes made to your home. Are all the occupants affected? Are people who spend the most time in the house most affected? Do occupants feel better when they leave the house? Are children or the elderly showing more pronounced symptoms? Are there times of the day or activities in certain rooms that make symptoms worse? "Yes" answers to any of these questions may help you further pinpoint the source of the problem.
If you find a solid match in both symptoms and sources, and your analysis of your home turns up some suggestive patterns, you should test for the substance to see if it is present in your home.
Chemical sensitivity has come largely as a surprise to medical science. When extensive testing of chemicals began back in the 1960s, toxicologists found little evidence of profound health effects from low doses of most substances they tested. Laboratory animals usually showed an admirable degree of tolerance. No matter that the animals' life spans were too short to demonstrate long-term effects — or that, of the 50,000 to 60,000 chemicals in common use, less than 2% had been thoroughly tested.
Ignorance being blindness (if not bliss), when a few people had unusually strong reactions to comparatively small concentrations of chemicals such as formaldehyde, chemical sensitivity was thought to be quite rare. Individuals so afflicted were viewed as unfortunate physiological misfits, people whose fallout from the human race was lamentable but probably unavoidable. Fortunately, since more and more people are now showing sensitivity, health experts' understanding of the problem is becoming considerably more sophisticated.
Perhaps the number one attitudinal breakthrough has been the realization that most chemically sensitive people aren't born that way. Though they may have enzymatic deficiencies that predispose them toward it, they develop their sensitivity after, sometimes long after, birth. This commonly occurs following extended exposure to low levels of one or more toxins, a single massive exposure to one toxin, or exposure in conjunction with a major injury or infectious illness.
In simple terms, what happens is that the body's immune and detoxification systems begin to work incorrectly or inadequately. The immune system — consisting of a number of substances in the blood — may overreact to small doses of toxins, or the inner-cell enzymatic system that normally removes toxic substances may become ineffective, allowing accumulation of toxins.
It might be formaldehyde, phenol, or dust mite antigen that triggers the sensitivity, but once sensitized, an individual may have severe reactions to a number of toxins in concentrations almost too small to measure.
Testing for a few of the most hazardous chemicals — notably formaldehyde, lead, combustion products and a variety of toxins in water — is fairly easy, accurate and economical. And an allergist might be able to check for populations of fungi and dust mites or at least determine your sensitivity to these things. But more esoteric contaminants require sophisticated equipment and expertise to measure. Check your yellow pages for environmental consultants, or visit Environmental Health Watch (http://www.ehw.org/ ). The following are a few recognized sources for mail-order testing:
• Carbon monoxide: Quantum Group
• Formaldehyde: Applied Technical Services
• Water (for most contaminants): National Testing Labs
Helping people who have already developed sensitivity is beyond the scope of this article. Our goals are to tell you about some of the pollutants that may be in your home, to help you recognize symptoms they may be causing, and to explain some ways you can cut your exposure to such pollutants.
It's important to understand that the development of chemical sensitivity is often a result of a combination of physical and mental factors, not just exposure to one chemical. The overall stress level on the body — which includes pressure from toxins of many varieties, infectious health problems, environmental factors such as temperature and humidity, and even the psychological strain of work or home life — determines the likelihood of whether a person will react severely to a chemical. Lead, for example, isn't considered a sensitizing chemical, but its toxic effects might make one more likely to react to other chemicals. Therefore, the best way to prevent sensitivity from developing — and, in fact, the usual way to treat the problem — is to reduce overall exposure to substances and conditions that stress the body.
Of course, though we're convinced that many people suffer unawares from environmental illnesses, we don't mean to imply that all or even most sickness is environmentally caused. Always rule out more-conventional health problems first! Physicians are still the authorities when it comes to diagnosing and treating illness, and you would be foolish to look for environmental causes of your problems without first having a thorough medical exam.
There are five basic ways to reduce or eliminate an indoor contamination problem: source removal, source isolation, ventilation, climate control and filtration. Each has its applications for certain situations, so let's look at them in more detail.
Source removal is the best solution to most chemical-sensitivity problems. But as John Bower points out in "Minimizing Indoor Air Pollution," this isn't always easy or inexpensive.
However, less severe symptoms, particularly those caused by consumer products, can often be inexpensively reduced by removing the products from the home. Heavy metals, solvents, pesticides, and many other toxins are simple enough to avoid, once you know where they come from.
If you have a problem with formaldehyde, fungi or dust mites, you should seriously consider getting rid of all carpeting. Either the carpet or pad may be a source for formaldehyde, and both form humid microclimates (despite controlled indoor air humidity) that are ideal for the growth of mold and dust mites. Those who are formaldehyde-sensitive should also avoid products made from medium-density fiberboard, panicle board, or hardwood plywood — materials used in some furniture, most cabinets and the subfloors of about 10 million U.S. homes (lift a warm-air register to examine a subfloor). Likewise, mobile homes (even those without ureaformaldehyde insulation) are probably off-limits for the formaldehyde-sensitive.
Lead problems with soldered pipes can be solved by replacement with plastic or silver-soldered-copper piping, but lead paint (the predominate source) presents particular difficulties, since it is very difficult and hazardous to remove. Don't attempt this yourself; hire a competent lead-abatement contractor to either remove all woodwork coated with lead-based paint (check kitchens, bathrooms and window frames indoors) or carefully encapsulate it.
Finally, it's probably a good idea for everyone, even those who aren't sensitive, to remove all unvented combustion appliances from their homes.
Source isolation: In some cases, it may be possible to seal off an offending pollutant from the indoor environment. For example, problems with pesticides from the ground penetrating the floor of the house can be eased by sealing off the crawlspace from the house.
Also, according to Dr. Thad Godish, of Ball State University's Indoor Air Quality Research Laboratory, covering surfaces such as cabinets and paneling with two coats of nitrocellulose-based varnish will reduce formaldehyde emissions by about 70%. Unfortunately, most such products contain toluene and xylene, thereby introducing other potential problems. No other known coating is an effective sealant, and many (including popular Swedish floor coatings such as Glitsa and the product used on nearly all hardwood cabinets and much fine furniture) are potent formaldehyde emitters themselves.
Ventilation will reduce an indoor air-quality problem by diluting the source, but it's usually not more than a partial or temporary solution. An air-to-air heat exchanger helps, but it won't cure most problems. Opening windows works in summer, and, short of leaving, it may be the only way to catch your breath and recover your senses well enough to plan a real solution.
Climate control can be a big help in reducing a number of indoor air-quality problems. Humidity above 50% or below 30% encourages numerous undesirable fungi and the dust mites that work in cooperation with them. This may mean using a humidifier in the winter, but the belt-driven and ultrasonic types make great incubators for mold unless used correctly and cleaned frequently. High humidity also increases the release of formaldehyde — as much as 1% increase for each 1% of relative humidity, according to Thad Godish. In addition, temperature affects formaldehyde outgassing; concentrations in the air are twice as high at 80 °F as they are at 70°F. (For these reasons, Godish recommends testing for formaldehyde in the spring or fall, not in the winter.)
Filtration can be quite effective, but the filters that work are generally not featured in television commercials. Electrostatic filters, which are widely available, help reduce mold populations, which in turn may limit the dust mites that feed on them. Some of these devices, however, produce ozone, so you should have a guarantee from the manufacturer that the device doesn't, and won't in the future, make ozone.
High-efficiency particulate (HEPA) filters are the most effective. They will remove almost all particles — including dust, smoke, pollen, fumes, molds, viruses, and many gases — down to a very small size (about 0.3 microns). Likewise, charcoal filters are effective on some substances, especially particles and chlorinated hydrocarbons. Neither comes cheap, though, and they do require maintenance. (Contact Airguard Industries for information about their filters.) HEPA vacuum cleaners may also help people with mold and dust-mite problems. Most such vacuums are industrial in size and cost, but Nilfisk of America does offer one small model for around $300. Other types of vacuum cleaners, such as the new water vacuums, are not considered effective on most toxins and may, in fact, make matters worse by forcing them into the air.
The topics we've covered here really provide little more than an overview of a very complicated subject. It's taken us centuries of neglect to foul our nests so thoroughly, and we'll not set things right overnight. Nonetheless, correcting our complacent attitudes about the home environment — setting aside some of those cherished homilies — may be the best start we can make at the even more daunting task of healing our whole planet's environment.
The following books will help you learn more about the causes of and cures for environmental illness:
The 1988 Healthy House Catalog by Environmental Health Watch and Housing Resource Center, $17 postage paid. A spiral-bound directory of products, companies, and information sources.
The Nontoxic Home by Debra Lynn Dadd. J.P. Tarcher, Los Angeles, $9.95. Protecting oneself from everyday toxins in the environment.
The Secret House by David Bodanis. Simon & Schuster, 1986, $9.95. A microscopic view of what goes on inside our homes. Exceedingly entertaining and alarming.
Your Home, Your Health, and Well-Being by David Rousseau, W.J. Rea, M.D. and Jean Enwright. Hartley and Marks, Vancouver, B.C., 1988, $19.95. Comprehensive treatment of indoor pollution sources, chemical sensitivity and renovation and construction to lessen exposure.
The Healthy House by John Bower. Lyle Stuart Inc., 1989, $17.95. How to buy or build a healthy house; how to cure a sick one.