What Are the Causes of Indoor Air Pollution?

Lung diseases such as respiratory tract infections, asthma and lung cancer commonly are caused by air pollution. The American Lung Association (ALA) claims that lung disease is the third leading cause of death in the United States. There are many sources of indoor air pollution that release gases or particles into the air. These sources are the main cause of indoor air quality problems, especially in homes.

• Fireplace

Combustion Sources

• Heating systems and other home appliances such as fireplaces, wood stoves, chimneys, water heaters, dryers and kerosene heaters contribute to indoor air pollution. These may use gas, oil, kerosene, coal or wood and can produce several products such as carbon monoxide and nitrogen dioxide. Additionally, tobacco smoke--which contains about 4,000 chemicals, 43 carcinogens, formaldehyde and carbon monoxide--also contributes to indoor pollution.

Building Materials

• Asbestos is a mineral fiber commonly used to produce fireproof articles and can be found in building construction materials such as pipe and furnace insulation materials, asbestos shingles, millboard, textured paints and floor tiles. When attempting to remove materials containing asbestos, toxic asbestos fibers may be released into the air, thereby increasing indoor asbestos levels. Commonly present in older homes, the use of asbestos has been limited today.

Furniture

• Furniture made of certain pressed wood products contributes to indoor pollution because of the presence of formaldehyde. Formaldehyde is a chemical often used to manufacture building materials and household products. The major sources of formaldehyde indoors are pressed wood products, typically made using adhesives that contain formaldehyde resins. They are found in particleboard, hardwood plywood paneling, softwood plywood, oriented strand board and medium-density fiberboard.

Household Cleaning Products

• Volatile organic compounds (VOCs) are toxic gases released from products such as paint, lacquer, paint stripper, cleansers and disinfectants, pesticides, building materials, furniture, wood preservatives, aerosol spray, moth repellent, air freshener, stored fuel, automotive products and dry-cleaned clothing. Office supplies such as copy machines and printers, correction fluid, carbonless copy paper, glue and markers also contain VOCs. These compounds are released by thousands of products and can stay in the air while they are being used, long after they are used and sometimes even when products are stored.

Outdoor Sources

• According to the World Health Organization (WHO), radon, which is a cancer-causing, naturally occurring, radioactive gas, is a worldwide health risk in homes. It cannot be seen, smelled or tasted and enters homes through cracks in the floor, walls, drains and other openings. The ALA states that indoor radon exposure is estimated to be the second leading cause of lung cancer. Additionally, according to the U.S. Environmental Protection Agency (EPA), it is the leading cause of lung cancer among non-smokers.

  Pesticides include products such as insecticides and disinfectants in spray, liquid, stick or powder form and often are used inside the home. Pesticides also can enter the home from soil or dust that drifts or is tracked indoors by people who step on contaminated soil.