It may surprise you to hear that the quality of the air inside your home is often worse than it is outdoors.  In the average home, dust, allergens, chemicals, smoke, and other pollutants can reach dangerous levels.  These unwelcome ingredients in our indoor air can contribute to drowsiness, headaches, memory loss, and lung disease among other problems.  Ironically, changes in home construction to improve energy efficiency have contributed to the problem.

If a home does not have an effective air exchange system in place to bring fresh air inside, stale, unhealthy air can become trapped indoors.  Since it is not economical to keep the windows open during cold weather, homeowners have two options: reduce the sources of pollution within your home and clean the air.

What are the sources of indoor air pollution and how can you reduce their presence in your home? 

Home Renovation:
If you've done some form of home renovation such as repainting a room, stripping and varnishing a table, or gluing together storage boxes, you've likely done a lot more than create an attractive home-you've inadvertently released unhealthy compounds into the air.  Oil paint, latex paint and thinner all contain solvents, which can lead to respiration problems particularly in children.  These products and most types of glue also contain toluene a chemical which can have adverse effects on the brain and respiratory system.  Chemicals continue to be released from these products for days or even months.

One of the best ways to reduce indoor air pollution is to work outdoors or in a separate workshop when you need to paint, varnish, or use any type of sealant or solvent.  Allow the item to dry completely outdoors.  When you paint a room, open the windows to bring in fresh air.  Close the doors and vents so that you do not allow fumes to get into your ventilation system.  Despite being in a well-ventilated space, you will still be exposed to chemicals through your lungs and skin.  Water-based paints are generally safer than oil-based paints and will dry faster.  Responding to consumer demands, many manufacturers of paints and solvents have developed low-fume, less toxic products.  You can now also find alternatives to traditional mineral spirit paint thinner such as those made with an extract of oranges.

Dry Cleaning
Perchloroethylene is the chemical most widely used in dry cleaning, according to the Environmental Protection Agency.  In laboratory studies, it has been shown to cause cancer in animals.  Recent studies indicate that people breathe in low levels of this chemical both in homes where dry-cleaned goods are stored and as they wear dry-cleaned clothing.  Although dry cleaners recapture much of the perchloroethylene in the cleaning process so that they can reuse it, varying amounts of this chemical remain in the clothing.  Dry cleaning also involves trichloroethylene, a chemical associated with liver cancer.  If you pick up your clothing and find that it has a strong odour, it is your prerogative to ask the cleaners to dry it properly.  To minimize your exposure (and save money in the process) check the labels on clothing before you purchase and opt for items that don't require dry cleaning.

Smoke
Nowadays most people know that smoking is unhealthy and smoking indoors is even worse.  The smell and the many chemicals released by cigarettes and cigars linger in the air.  Light up outdoors and ask your family and your guests to do the same.  This will help to reduce the fire hazard as well.

Another source of smoke is candles.  Not all candles are created equal and thus not all produce the same amount or types of smoke.  Most are made from petroleum, some from vegetable oil (e.g., soy oil), or animal fat, and others are made from beeswax.  Those made from vegetable oil or beeswax typically produce the least smoke and tend to drip less.

One of the greatest sources of indoor smoke is from burning wood indoors in a fireplace or a stove.  When wood burns, it releases dozens of chemicals and gases into the air including carbon monoxide and creosote.  People die every year from carbon monoxide poisoning when using wood-burning fireplaces and stoves in poorly ventilated rooms.  Because it's necessary to have proper ventilation, wood becomes a fairly ineffective source of heat.  If you love to huddle around a real fireplace on a chilly evening, make sure that you have your chimney ‘swept' regularly and that the flue at the roof opening is not clogged with leaves or other debris.  

Beauty Product
The common beauty routine of applying perfume, make-up and nail polish, and using an assortment of hair dyes, bleach and hair removers involves a long list of chemicals, many of which can enter the skin and/or become airborne.  Beauty is a dangerous and often smelly process!  Although government agencies regulate most products, the standards are not as stringent as they are for food items.  Studies have shown, for example, that hairdressers have a higher than average incidence non-Hodgkin's lymphoma and bladder cancer.  (Books such as The Safe Shopper's Bible provide details about the chemicals and known cancer-causing agents in many common brands.)  When using these products ensure that the room is well ventilated to the outdoors either by using a fan or opening a window.

The Great Outdoors?
Throughout this article you see suggestions to open a window for ventilation.  If you live near a busy road or in a large city it may not feel like the outdoor air is much cleaner.  Plants are one way you can help to clean the air where you live.  If you live on a busy street, consider planting a row of high evergreens to block some of the exhaust and noise.  Plants will also absorb some of the carbon dioxide released by vehicles.  Indoors, there are many plants that will help to remove airborne chemicals.  For example, Gerbera Daisies and Chrysanthemums were found to be effective in the removal of benzene while Philodendrons helped to reduce airborne formaldehyde.

Air Purifiers
As amazing as it sounds, some models of air purifiers actually add to indoor air pollution by emitting ozone, the most harmful component of smog.  Electronic filters, generally marketed as electronic air cleaners, electrostatic precipitators and "ionizers" can also produce ozone, either as a by-product of use or intentionally.  The American Lung Association and the California Department of Health have conducted studies of these appliances and have found that many of these appliances are not labeled properly to indicate that they produce ozone.  Moderate levels of this gas can irritate eyes, nose, throat and lungs.  Some asthmatic individuals are more susceptible to ozone toxicity and can experience constricted airways.

A safer choice is a HEPA (High Efficiency Particle Arrestor) air cleaner.  However, the American Lung Association recommends that the most effective way to get healthy air is to stop air pollution at its source.  By changing the air filters in your heating and cooling system on a regular basis and implementing some of the suggestions in this article, you will help keep you and your family breathing easy.