Alternative Paints Won't Seal Particle Board Adequately

DEAR MS. H.E.: In your article on formaldehyde, Richard Knights of Blue Sky Testing Labs suggested sealing particle board with three coats of oil-based paint or polyurethane. Later, I read an article on healthy houses. The writer discussed using nontoxic materials. What is a nontoxic or low-toxic sealant? Do three coats of the nontoxic or low-toxic sealant work the same as, or is it as good as, oil-based paint or polyurethane for sealing particle board? Also, what is vapor-barrier paint?

DEAR READER: The kinds of alternative paints you'll read about in an article or book on "healthy homes" won't do an adequate job of sealing particle board. Nor will "vapor barrier" paints, which lay down a thin plastic film to stop moisture, but will not stop formaldehyde gas. According to Knights, the two best particle-board sealants that are also fairly nontoxic are water-based polyurethane and something called nitrocellulose lacquer. Both of these finishes are clear. If your particle board will show, and you need a paint, you will have to use oil-based paint.

The toxicity of paint has to do with the solvents that are used. Water-based paints are fairly nontoxic. Oil-based paints and finishes contain petroleum-based solvents that can be very nasty until the paint is completely cured.

You don't say in your letter whether you are sensitive to chemicals. If so, the polyurethane may not bother you. The nitrocellulose may, but it will evaporate much more quickly than will oil-based paint, the solvents from which can irritate sensitive individuals for weeks. Once these materials have cured, they are not toxic.

DEAR MS. H.E.: Would a car ionizer be effective for me? I drive around on my job and have an allergy problem. I've often wondered about air pollution as I wend my way through heavy traffic. I'm enclosing a photo copy of an ionizer I saw advertised in the Real Goods fall catalog.

DEAR READER: An ionizer negatively charges particles in the air and causes them to plate out on surfaces. This can get really messy, really fast. Though it might alleviate your allergies, you'd have to wipe down the inside of your car regularly. If you think air pollution is aggravating your health, you would do better with an air cleaner, especially one that has a carbon or charcoal filter in addition to a particulate filter. The filter can remove particles from the air, as an ionizer does, and the charcoal or carbon can remove gases such as carbon monoxide from the air.

Look in the Yellow Pages under Air Cleaning and Purifying Equipment to find a local source of air filters.

One out-of-state source whom Knights recommends is Jim Nigra of Nigra Enterprises in Agoura, Calif., 1-818-889-6877. Nigra is a broker for home environmental systems and equipment including air, water, heat, lighting, paints and sealants.

If you're not sure that you need an air cleaner (it may cost as much as $150-$200), try this: Whenever you're away from heavy traffic, open your windows or turn the air intake to "fresh." When you're in traffic, or idling behind a stopped car at a light, keep your windows closed and your vent on recirculated air.

DEAR MS. H.E.: We recently purchased a 50-year-old home from the original owner. The furnace is forced-air oil with a newer flame-retention burner. The house had been smoked in very heavily for 50 years and the windows were almost never opened. It took us months to rid the home of all tobacco and nicotine damage and smell. My question is: Does the furnace and/or the duct work recycle any of this back into our new "clean-air home"? We had the ducts vacuumed and furnace chimney cleaned.

DEAR READER: This is a question your nose can answer best. Heavy smoking probably did leave a residue of tar on the inside surfaces of your ducts. But if those deposits are acting as a reservoir of air pollution, you would know it. Does the house begin to smell bad when you turn the heat on, or after the heat has been on for a while? If the answer is no - sniff at the register if you're unsure - don't worry. If you do smell tobacco in the air, and you think it's coming from the heat registers, you can have your duct work scrubbed. Look under Furnace Cleaners in the Yellow Pages and choose one that can do more than just vacuum the ducts.

Susan McGrath's column runs every two weeks in the Home/Real Estate section of The Times. Send questions and comments to: The Household Environmentalist, P.O. Box 70, Seattle, WA, 98111.