Home sick home
It’s hard to imagine a comfy home becoming a house of horrors, but research shows that the air inside your house is probably more dangerous than the air in a factory-filled city. Cabinets ooze toxic emissions, carpets can become poison pits and woodstoves choke the life right out of you if you don’t treat them right.Scary? It’s enough to make you want to pitch your tent in the wilderness. Before you do, though, remember that knowledge is power, particularly in the case of indoor air pollution.
Most people spend about 90 per cent of their time indoors, which is why environmental agencies place indoor air pollution at the top of their list of environmental hazards.
Canadian studies show that levels of certain pollutants, such as formaldehyde, can be four to seven times higher inside the home than outside. But there a no rules regulating the quality of indoor air, like there are for outdoor pollution. “If truckloads of dust with the same concentration of toxic chemicals found in most carpets were deposited outside, these locations would be considered hazardous-waste dumps,” says environmental resecher John W. Roberts.
Indoor pollution was exacerbated in the 1970s by a well-intentioned effort to conserve energy. In the flurry of weatherstripping that followed the Middle East oil crisis, people removed all the sources of fresh air infiltration, effectively trapping the toxic substances emitted by household materials and furnishings.
Sick building syndrome
People who live or work in hermetically-sealed buildings often suffer from headaches, aching joints and breathing problems. Prolonged exposure can lead to depression, forgetfulness and a spaced-out feeling. Sick building syndrome, as it is called, disappears when the sufferers leave the offending building, or replace synthetic furnishings with natural products.
Although the human body is able to rid itself of the contaminants in stagnant air, previous exposure to chemicals increases the total load, making it harder to detoxify the system. The risks are greater for the very young and very old. Small body weight is the contributing factor in the young, while chronic diseases or weakened immune systems make the elderly less able to cope with contaminants.
Canadians lead way
The good news is that the indoor pollution problem has been identified and studied. Since the late 1970s, home builders have been designing homes that are energy-efficient and environmentally safe. Canada, in fact, leads the way in developing an internationally-recognized model of residential housing called R2000 homes.
“Canadians should not be afraid of their homes,” says Gary Sharp, of the Canadian Home Builders Association. While R2000 homes may cost consumers about three per cent more than the conventional, they’re built with superior ventilation systems and products that have less potential to “outgas” — natural wood floors, low-emitting carpets, water-based paints and ceramic tiles to name a few.
What you can do
And there are other steps to take. Those who are extremely sensitive to chemicals in the environment should ask their home builders to adopt additional steps, Sharp says. He notes a housing project in Ottawa where homes were built with chemically inert concrete floors and walls. And nails used to build the homes were first boiled to remove offending oils. Builders were not even allowed to smoke on the job site in case the materials they were using soaked up the toxic cigarette smoke.
“You can build a hazard-free home,” Sharp says, “but it is an extreme measure.”
For most people, a bit of research and common sense will ensure a healthy indoor environment. Here are some of the ways to rid your home of the worse sources of pollution.
Tobacco smoke is the largest contributor to indoor air pollution. If you don’t smoke but live with someone who does, you still have a higher risk of lung cancer than someone who lives in a smoke-free home.
Air-filtering devices are not totally effective at eliminating toxins, as they mainly remove the solid particles of the smoke, not the gases. The best solution is to stop smoking. If you must, smoke outside.
Radon is radioactive gas found throughout the earth’s crust. The amount of radon in a home is linked to the uranium content of the surrounding soil. It seeps through cracks in concrete walls, basement drains and joints.
While the Environmental Protection Agency (EPA) in the United States ranks radon high in the risk factors for indoor air quality, Health Canada does not consider radon a serious threat in Canadian homes.
Since radon is a carcinogen, however, Health Canada recommends remedial action if radon levels exceed 800 Becquerels per cubic metre (Bq/m3). The EPA in the United States takes a tougher stance and recommends action if radon levels reach 148 Bq/m3.
You can hire an air specialist to check radon levels in your house or use a sampling kit. The latter is a gas-absorbing charcoal canister that you expose to the air over a two-day period, then send to a laboratory for analysis.
Carbon monoxide is a colourless, odourless and tasteless gas produced when fuels such as wood, gas, oil and kerosene are burned. Once absorbed, carbon monoxide inhibits the blood’s capacity to carry oxygen, eventually suffocating the victim.
Poorly vented or improperly-operated woodstoves, gas stoves and kerosene heaters are the main source of carbon monoxide poisoning in Canada. Health Canada sets the maximum allowable level for exposure to carbon monoxide (in a one-hour period) at 25 parts per million. Amazingly, studies have found that the levels of carbon monoxide in some Canadian kitchens rise to 100 parts per million immediately after gas stoves were used for cooking.
To protect yourself install carbon monoxide detectors throughout your home. Have your central heating system inspected annually. Make sure gas appliances work properly and are vented to the outdoors. Check that your fireplace or woodstove is in good working condition and never leave a car running in an attached garage.
Formaldehyde is used in a wide range of products including particleboard, plywood, shelving, furniture, carpets, draperies, fabric, permanent press clothes, paints, shellacs, waxes, polishes, glues, molded plastic, insecticides, fumigants, disinfectants, deodorants, shampoos and household cleaning products. Through a process called outgassing, formaldehyde evaporates and contaminates the air, causing chronic headaches and periodic memory lapses.
The most notorious source of formaldehyde was a insulating material called urea-formaldehyde foam insulation (UFFI), which was pumped into the walls as an energy conservation measure. (The product is rarely used today.)
To avoid the problems associated with formaldehyde, select products that do not contain it. Choose natural wood and natural fibres in your home. Paint over hardwood panelling or particleboard cabinets with a water-based sealant or polyurethane varnish to reduce emissions.
Getting rid of UFFI is a more difficult task. You must rip open the walls of your home and scrape the foam from the studs, then put up new wallboard and trim. Unless you are extremely sensitive to formaldehyde, a better solution is to keep humidity levels low if UFFI is present, because the resins outgas more rapidly in humid conditions.
Volatile organic compounds
Volatile organic compounds (VOCs) are emitted from a host of common household products — waxes, paints, shellacs, plastic, disinfectants, cleaners, pesticides, aerosol sprays, shoe polish, hobby materials, glue, inks, ceramic glazes and recently dry-cleaned clothes.
The glue used to install wall-to-wall carpeting is particularly offensive. People can actually become nauseated from the smell. If possible, have your carpet installer air out your carpet before he puts it in your home. Open windows during and after installation for at least 48 to 72 hours. Better yet, leave home during the installation.
Another VOC, benzene, which is found in solvents, putty and filler, is known to cause cancer. Other suspected carcinogens include: trichloroethylene (TCE) and methylene chloride (both found in some shoe polishes); perchloroethylene (used in dry-cleaning fluid); and polychlorinated biphenyls (PCBs) — found in electrical components, waste oil products and some plastics.
To eliminate the problems caused by VOCs, choose natural furnishings and clothing and toxic-free cleaning products.
As a preventative measure, turn on your exhaust fan or open the windows when using VOC-rich products. Whenever possible take hobby projects outside. Store paint, fuel and pesticides in a well-ventilated part of your house, or in a separate building.
Asbestos is a fibrous substance valued for its insulating and fire-retarding capabilities. It can be found in acoustic ceiling tiles, duct insulation and ventilation shafts. It was also found in gypsum wallboard, textured paint, joint and spackling compounds in homes built before the 1970s.
When released in the air, asbestos fibres lodge in the lungs. Prolonged exposure has been linked to asbestosis, lung cancer and mesothelioma.
If left intact, asbestos fibre should not present a danger to the public, according to Health Canada. The problem comes when the material starts to crumble or is ripped out during a renovation project. At such times, precautions should be taken to minimize inhalation of, and contact with, asbestos. Materials containing asbestos should be examined periodically for signs of deterioration.
Lead and pesticides in carpets
Breathing or ingesting lead can damage the brain, kidneys and reproductive system. Banning lead in gasoline has helped reduce lead exposure in Canada, but lead particles still find their way into homes as dust, often in the dirt on people’s shoes.
The most common source of air-borne contamination is lead-based paint in older homes. (Lead pipes and lead solder in the residential plumbing is other source). While the United States has banned the sale of all lead-containing paints, Canada still allows lead in exterior paint.
Pesticides that break down within days outdoors may last for years in carpets. Even though DDT was banned decades ago, it still showed up in carpet dust samples taken from a quarter of the homes in a 1992 study in the Midwestern States.
Installing a good quality doormat or removing your shoes before entering a house helps keep lead and pesticide residue outside. When in doubt, vacuum! It may take a year of normal cleaning to remove the large amount of lead collected in the carpet of an older home.
Microscopic organisms, including mould, mildew, fungi and bacteria, thrive in moist environments. Reducing humidity levels through ventilation helps reduce microbial growth. Stagnant water sources, such as humidifier tanks, should be cleaned and disinfected regularly. Rigorous cleaning also helps.
Canada Mortgage and Housing Corporation has a number of publications on healthy housing, including a Healthy Housing Renovation Planner. You can order these publications by calling 1-800-668-2642.