While building “green” has been gaining momentum over the last few years, indoor air quality has actually taken a back seat. The level of energy efficiency in new homes has increased, and will continue to increase when the updated Ontario building code requiring better energy efficiency takes effect next year. But, unless there is a stronger emphasis on ventilation and an avoidance of building products that release or off-gas toxic chemicals, indoor air quality will continue to erode. And it doesn’t matter if you buy a $300,000 home or a $2 million dollar home. Toxic building products are used in every new home built in Ontario.
In a recent report from Environmental Defence—Polluted Children, Toxic Nation: A Report on Pollution in Canadian Families—lab tests found that adults had an average of 32 toxins in their bodies while children had 23. Although the test group was small, 13 people from across Canada , it has spurred Health Canada to begin a larger, national program tracking toxic substances next year.
The report also revealed three significant findings that cannot be ignored. First, the toxins found are known carcinogens; second, every child tested had at least one toxin at a higher level than the adults; and third, many of the toxins found exist in all of our homes.
Probably the most ubiquitous building product in every new home is particle board, which can be found in sub-floors, cabinet boxes, shelves, closets, interior doors, window bases, moulding and kitchen cabinet doors. Particle board can take the form of plywood, MDF or oriented strand board.
Dan Morris, an engineer who is president of Healthy Building Inc. and teaches a sustainability building advisor certificate program at Seattle Community College in Washington State , says that particle board is a composite product made with sawdust and formaldehyde.
“It is used anywhere in a house that used to be wood,” he says, “and it is one of the worst things we have ever put into housing. Its half-life is between 10 and 40 years which means it will off-gas formaldehyde for a long time. MDF has a higher density than plywood so the formaldehyde comes out a bit slower than in plywood.”
Dr. Kapil Khatter, director of health and environment for Pollution Watch and president of Canadian Physicians for the Environment, says “formaldehyde is certainly a carcinogen and the best thing is not to buy particle board at all.”
Renee Bergeron, media relations officer for Health Canada, says formaldehyde is present at low levels in all Canadian buildings. In an e-mail, she stated that most homes tested in Canadian studies had formaldehyde levels below the Health Canada guideline. She does state that we can lower our exposure to formaldehyde by increasing the flow of outdoor air to the inside, which means increased ventilation. She also agrees that “wood-based products assembled with urea-formaldehyde resins (particle board, MDF) emit more formaldehyde than those assembled with phenol-formaldehyde resins (e.g. oriented strand board), and bare products emit more than coated products.”
Although Canadian-made particle boards are tested on a regular basis for entry into the Japanese market, and have the best rating going into this market, we import a lot of the particle board used in our own new homes. And this is not tested nor is there legislation mandating testing of these imported building products.
Dale Black, manager of quality management systems for the Canadian Plywood Association, says currently Canada does not test for formaldehyde for imported plywood and MDF.
“I am not aware of any legislation, provincial or federal, that mandates panel products must be tested,” he says. “And plywood is coming into Canada from other countries like China and Brazil . It has come to our attention that a person building a home in Toronto used plywood and it off-gassed terribly.”
Morris, who says the same problem exists in the U.S. , attributes it to free trade.
“In the late 80’s we had lowered formaldehyde by 70 per cent,” he says. “In the late 90’s, with free trade, formaldehyde was going up again. The reason is we can’t tell any other country what to do or how to make products. So we are importing lots of particle board from Mexico which has lots of formaldehyde.”
Complicating this increase in formaldehyde levels, is the tighter, more energy efficient homes being built. With nowhere for the chemicals to go, they remain in homes for people to breathe in.
In tighter houses with more energy efficiency, pollutants build up and are harder to get rid of,” says Morris, who believes the biggest problem in new homes today is inadequate ventilation. “In houses with poor ventilation, dust can get to be 500,000 particles per cubic foot of air that you breathe. I think there is a conflict between green building and indoor air quality.”
Morris’s advice to homebuilders is simple: “If in doubt, keep it out” and provide good ventilation in all new homes. Morris would like to see heat recovery ventilation systems in new, energy efficient homes. This would allow fresh air to enter the house through a single intake and then be distributed through ducts to other rooms. Stale, polluted air would be removed through a separate exhaust duct.
Sarah Winterton, executive director for Environmental Defence, and Dr. Khatter say the study proposed by Health Canada for next year, should start now and that we should be getting rid of known products with toxic chemicals as soon as possible.
“It’s a matter of mandating industry to implement pollution plans and implement products with safer materials,” says Winterton. “Should products with toxic chemicals be created in the first place?”