That Formaldehyde Feeling, Part Ii

Formaldehyde is a useful chemical, and we use a lot of it. If the Formaldehyde Institute would return my calls I could tell you how much of it we use every year - a figure in the billions of pounds, anyway. Some fraction of those billions of pounds may have ended up in your home. If enough of it has, it may be making you sick, whether you know it or not.

Feeling groggy whenever you're home for long? Red eyes, stuffiness? Unexplained nose bleeds? Odd memory lapses? Chronic respiratory problems? According to allergist Dr. Gordon Baker, of Burien, these can all be symptoms of exposure to formaldehyde.

If you have these symptoms, you should have your home tested for formaldehyde. (Call the Environmental Protection Agency, at 553-4973, for a list of testing labs. The number for outside Seattle, listed incorrectly in this column last week, should be 1-800-424-4372.)

If you're not sick, especially concerned or sensitive, don't bother having your home tested. But there are steps you can take to help make sure your home isn't emitting a lot of formaldehyde, and you should probably take them in any case. Long-term exposure to fomaldehyde is a good thing to avoid.

Experts on indoor air quality recommend that you locate sources of formaldehyde in your home and either remove them or seal them, limiting their ability to "outgas" in your breathing space. Richard Knights, a Seattle chemist and formaldehyde sleuth extraordinaire, identifies the top three sources of formaldehyde as "particle board, particle board and particle board."

(Knights uses particle board as a generic term for a variety of pressed wood products, including particle board and medium-density fiberboard. For the purposes of this article, I will do the same.)

Particle board is composed basically of sawdust or wood chips and urea-formaldehyde glue. According to Knights, this inexpensive wood product will outgas formaldehyde virtually forever. If you have extensive amounts of unsealed particle board, you most likely have a lot of formaldehyde.

The first place to look for it is the floor. Do you have wall-to-wall carpeting? What's under it? If you don't know, take a look. If you have heat registers in the floor, simply lift one up. Otherwise, peel back the carpet and the pad in one corner of a room. Make sure that you peel back far enough to expose unpainted flooring.

Does the wood you expose have a one-directional grain? Can you gouge long splinters from it? If so, then it's plywood or oriented strand board, and you don't have a problem. If there is no grain, and the wood particles are, well, particles, then it's particle board and you may have a problem.

Next question: What lies between the carpet and the wood? A plastic or rubber barrier is what you want. A carpet pad that is slick and plasticky, or rubber waffle foam, might be an adequate barrier. Rebond pad, a multicolored chopped foam pad, and most other carpet pads are not a barrier to formaldehyde. If this is what you have, you'll need to seal the floor.

If you have symptoms of formaldehyde exposure, pull up that carpet and pad right away. Cover the underlying wood with a thick sheet of plastic and then recarpet the floors. Carpets made around 1980 may contain formaldehyde in their glues. If your carpet dates from around then, toss it or test it. If it is newer, Knights suggests you replace it if you wish or go ahead and reinstall it if you need to save money, because it will soon outgas any formaldehyde it has picked up from the floor.

If you have allergies, consider ditching carpeting altogether. Cover your floors with hardwood or vinyl flooring. These will shut out formaldehyde coming from the subfloor and won't harbor dust particles.

If the formaldehyde isn't causing problems for you or your housemates, you can wait until the carpet needs replacing anyway, then install the plastic barrier.

Particle board shelving is the another biggie. If you can, simply replace such shelves with solid wood, exterior-grade plywood or plastic-laminated particle board. If replacing them is out, seal them.

Knights has found that three coats of oil-based paint or polyurethane cuts outgasing by about 90 percent. These coatings aren't exactly wearing white hats themselves - they release toxic solvents into your air as they dry, and they contribute to smog.

But they do dry up and get it over with, unlike particle board, which will outgas merrily ever after.

Another option for shelf tops is heavy plastic shelf liner - the kind that sticks to the wood. Be sure to seal the undersides of shelves, too. Any exposed particle board will outgas formaldehyde.

Kitchen cabinets are another place Knights looks for extensive use of particle board. Again, three coats of oil-based paint will seal these. If your countertops are laminated particle board (peek underneath a counter), you may need to seal the underside of these, too.

Some unpainted wood cabinets are made of hardwood plywood, such as birch or ash. These are also made with urea-formaldehyde glues, and sensitive people may react to formaldehyde from them.

You can try sealing these with three coats of polyurethane. Particle board furniture is the last big category. Small fry, such as stereo speakers, aren't normally a problem. But large pieces, such as the big "entertainment centers" in which you store a stereo, a television and a VCR, can introduce acres of particle board. Paint these as described above, and do it outside, if possible.

Groan. This all sounds like an unbelievable pain in the neck, doesn't it? Why can't you just open a few windows? Install a fan? Blow away the formaldehyde?

No such luck. Appropriate ventilation IS the best approach to some indoor air problems, such as gas-burning stoves, but it won't help much with formaldehyde. Here's why: The formaldehyde that is in materials such as particle board outgases until an equilibrium is reached with the air around it. Blow away that old, formaldehyde-laden air, and the particle board will outgas a little faster. You could say that the formaldehyde in the board knows how much formaldehyde is in the air around it, and strives constantly to maintain it at a certain level.

However, since the air outside your house is considerably cleaner than the air inside it, opening windows is not a bad idea, weather permitting. Throw an extra blanket on the bed and fling open a bedroom window tonight.

Richard Knights, Ph.D., of Blue Sky Testing Labs provided technical information for this column. Dr. Gordon Baker, an allergist in Burien, contributed medical information.

Susan McGrath's column runs weekly in the Home/Real Estate section of The Times. Do you have a question about decisions you can make in your everyday life to help keep your household healthy? Have you found solutions? Send questions and comments to The Household Environmentalist, P.O. Box 70, Seattle, WA, 98111.