True or False: The Air Quality Inside Your Home is Better Than the Air Quality Outside
It might be true, but only if you live next door to a medical waste incinerator. If your home is average, your levels of indoor air pollution are probably worse than you think.

EPA research has shown that the air inside the typical house contains levels of pollutants 2-5 times higher than the air outside. In extreme cases it can be 100 times more polluted.

Various studies have placed the total number of indoor air contaminants at approximately 900. In one Consumer Product Safety Commission study of volatile organic compounds (a.k.a. VOCs), outdoor air at sampled sites contained less than 10 of these airborne chemical toxins while indoor air at those same sites contained 150.

Given that the average American spends about 90 percent of his or her time indoors, the EPA has ranked indoor air pollution as one of the top five environmental risks to public health.

The Atmos-Fear Inside
Though every home is different, poor indoor air quality has five basic causes:

1. The chemical substances we use to clean our homes and ourselves. Many homeowners use a large number of petrochemical cleaners, synthetic personal care items, and other toxic products like pesticides, disinfectants, and air deodorizers. These products spread hazardous fumes and compounds all over the house.
2. The materials we use to build and furnish our homes. Modern residences contain a variety of synthetic materials from carpets and foam cushions to insulation and chemically-treated wood products. Many of these products outgas, which means that the chemical compounds they contain break down over time and are slowly released into the air. This process is also called off-gassing.
3. Modern construction techniques. Today’s homes are far better insulated and more tightly sealed than any in the past. This is good for energy conservation but bad for indoor air quality. Without a system to ensure adequate air exchanges (something most houses lack), levels of hazardous indoor air pollutants tend to rise over time in homes designed to keep drafts (i.e. fresh air) out and warmed or cooled air trapped within.
4. Household combustion equipment like furnaces, hot water heaters, and gas stoves. If improperly maintained or vented, these devices can emit everything from particulates like soot to deadly gases like carbon monoxide.
5. Polluted outdoor air. In older homes, leaky windows, loose doors, poorly insulated walls, and drafty construction all allow outdoor air to make its way inside. While this air is often less polluted than the air indoors, anything it contains will tend to concentrate indoors over time.

A Volatile Subject
Some of the most common and hazardous kinds of indoor air pollutants are called Volatile Organic Compounds (VOCs), carbon-based compounds that easily form vapors at room temperature. In the home, these chemicals come predominantly from two sources: the outgassing of synthetic materials like foams and plastics and the use of toxic cleaning products and other household chemicals.

There are hundreds of VOCs capable of causing all kinds of illnesses and ailments. The only way to tell for sure if they’re in your home’s air supply is to buy a meter like the one we used on Big Green Lies. Otherwise, we usually can’t smell VOCs when at typical levels, all we can do is guess.

The good news is that it’s pretty simple to clean up your indoor air and banish VOCs and anything else that might be hiding there.

• First, don’t bring home any conventional cleaning or personal care products, perfumes, air fresheners or deodorizers, pesticides or anything else made from petrochemicals. If you don’t use these things, they can’t pollute your air!
• Second, open your doors and windows wide once in awhile (even in winter!) to replace bad stale air with good fresh air.

Back to all Big Green Lies articles

photo: metrocentric