Outdoor air pollution is dangerous, especially during the May-September smog season. But indoor air pollution poses a problem as well, and it’s one that has been around for a while.
In the 19th century, two of the most respected experts on the care and management of a household were daughters of famed clergyman Lyman Beecher: Harriet Beecher Stowe (author of Uncle Tom’s Cabin) and Catherine Beecher.
The sisters published a book on household management in 1869 entitled Principles of Domestic Science: as Applied to the Duties and Pleasures of Home. In one chapter, “Household Murder,” they talked about the need for ventilation to produce good indoor air quality. In another book, Miss Beecher’s Housekeeper and Healthkeeper, published in 1873, Catherine penned the following statement:
“The first and most indispensable requisite for health is pure air, both by day and night. If the parents of a family should daily withhold from their children a large portion of food needful to growth and health, and every night should administer to each a small dose of poison, it would be called murder of the most hideous character. But it is probable that more than one half of this nation are doing that very thing.”
The Beecher sisters didn’t mince words.
Today indoor air pollution may be 2-5 times (and occasionally more than 100 times) worse than outdoor air pollution, and the Environmental Protection Agency lists indoor air pollution as one of the top five public environmental health risks. This is troubling, since children spend approximately 90 percent of their time indoors.
While common indoor air pollutants cause many harmful effects, there is considerable uncertainty about what concentrations or periods of exposure are necessary to produce specific health problems. People also react very differently to indoor air pollutants. Some people have no known reactions. Others have asthma, allergies, respiratory ailments and chemical sensitivities. Further research is needed.
Various factors contribute to poor indoor air quality, including smoking, the use of synthetic building materials and furnishings, household cleaners and air fresheners, pesticides and reduced ventilation rates. Common toxins found in indoor air include: environmental tobacco smoke, nitrogen oxides, lead, carbon monoxide, radon, allergens, volatile organic compounds, or VOCs (e.g. formaldehyde), and soot.
The relative importance of any single source depends on how much of a given pollutant it emits and how hazardous those emissions are. In some cases, a source’s age or maintenance are significant. For example, an improperly adjusted gas stove can emit significantly more carbon monoxide than one that is properly adjusted.
Health effects from indoor air pollutants may be experienced soon after exposure or possibly years later.
Immediate health effects may show up after a single exposure or repeated exposures. These include irritation of the eyes, nose and throat, headaches, dizziness and fatigue. Such immediate effects are usually short-term and treatable. Sometimes the treatment is simply eliminating the person’s exposure to the source of the pollution, if it can be identified.
Certain immediate effects are similar to those from colds or other viral diseases, so it is often difficult to determine if the symptoms are a result of exposure to indoor air pollution. For this reason, it is important to pay attention to the time and place the symptoms occur. If the symptoms fade or go away when a person is away from the home and return when the person returns, an effort should be made to identify indoor air sources that may be possible causes.
The likelihood of immediate reactions to indoor air pollutants depends on several factors. Age and pre-existing medical conditions are two important influences. Children and the elderly are more vulnerable, as are people with asthma and other respiratory problems.
In other cases, whether a person reacts to a pollutant depends on individual sensitivity, which varies tremendously. Some people can become sensitized to biological pollutants after repeated exposures, and it appears that some people can become sensitized to chemical pollutants as well.
Long-term health effects may arise years after exposure or after long or repeated periods of exposure. These effects, which include some respiratory diseases, heart disease and cancer, can be severely debilitating or fatal.
It is prudent to try to improve your home’s indoor air quality even if symptoms are not noticeable.
For more information:
See the Indoor Air Pollution article on the Healthy Families, Healthy Environment Web site, http://www.healthyfamiliesnow.org/Article.asp?Record=1080.