People often think that respiratory illnesses and allergies can be avoided by minimizing exposure to the outdoor environment. The reality is that the air we breathe in our homes, in schools, and in offices can put us at risk even greater for health problems. Some pollutants can be chemicals, gases, and living organisms like mold and pests.

Some pollutants cause health problems such as sore eyes, burning in the nose and throat, headaches, or fatigue. Other pollutants cause or worsen allergies, respiratory illnesses (such as asthma), heart disease, cancer, and other serious long-term conditions. Sometimes individual pollutants at high concentrations, such as carbon monoxide, cause death.1

Indoor pollution sources that release gases or particles into the air are the primary cause of indoor air quality problems in homes. Inadequate ventilation can increase indoor pollutant levels by not bringing in enough outdoor air to dilute emissions from indoor sources and by not carrying indoor air pollutants out of the home. High temperature and humidity levels can also increase concentrations of some pollutants.

Understanding and controlling some of the following common pollutants found in your home can help improve your indoor air and reduce your family’s risk of health consequences related to indoor air quality.

Secondhand cigarette smoke is one of the easiest offenders to eradicate. If someone in your home smokes, make them quit or smoke exclusively outdoors. Secondhand tobacco smoke can cause cancer and serious respiratory illnesses. Children are especially vulnerable to secondhand smoke. It causes or worsens asthma symptoms and is linked to increased risks of ear infections.

Radon is a radioactive gas that is formed in the soil. It can enter indoors through cracks and openings in floors and walls that are in contact with the ground. Radon is the second leading cause of lung cancer overall.

Combustion Pollutants are gases or particles that come from burning materials. In homes, the major source of combustion pollutants are improperly vented or unvented fuel-burning appliances such as space heaters, woodstoves, gas stoves, water heaters, dryers, and fireplaces. The types and amounts of pollutants produced depend on the type of appliance, how well the appliance is installed, maintained, and vented, and the kind of fuel it uses. Common combustion pollutants include:

  • Carbon monoxide (CO) which is a colorless, odorless gas that interferes with the delivery of oxygen throughout the body. Carbon monoxide causes headaches, dizziness, weakness, nausea, and even death.
  • Nitrogen dioxide (NO2) which is a colorless, odorless gas that causes eye, nose and throat irritation, shortness of breath, and an increased risk of respiratory infection.

Volatile organic compounds (VOCs) are chemicals found in paints and lacquers, paint strippers, cleaning supplies, varnishes and waxes, pesticides, building materials and furnishings, office equipment, moth repellents, air fresheners, and dry-cleaned clothing. VOCs evaporate into the air when these products are used or sometimes even when they are stored.

Volatile organic compounds irritate the eyes, nose and throat, and cause headaches, nausea, and damage to the liver, kidneys, and central nervous system. Some of them can cause cancer.

Airborne particles found in homes, schools, and offices that trigger asthma include mold, dust mites, secondhand smoke, and pet dander. A home may have mold growing on a shower curtain, dust mites in pillows, blankets or stuffed animals, secondhand smoke in the air, and cat and dog hairs on the carpet or floors. Other common asthma triggers include some foods and pollutants in the air.

Airborne particles cause symptoms including coughing, chest tightness, wheezing, and breathing problems. An asthma attack occurs when symptoms keep getting worse or are suddenly very severe. Asthma attacks can be life threatening. However, mild asthma is controllable by reducing asthma triggers.

Molds are living things that produce spores, which float in the air, land on damp surfaces, and grow.  Inhaling or touching molds can cause hay fever-type symptoms such as sneezing, runny nose, red eyes, and skin rashes. Molds can also trigger asthma attacks.

Formaldehyde, a colorless, pungent-smelling gas, can cause watery eyes, burning sensations in the eyes and throat, nausea, and difficulty in breathing in some humans exposed at elevated levels (above 0.1 parts per million). Formaldehyde is a chemical used widely by industry to manufacture building materials and numerous household products. The most significant sources of formaldehyde are likely to be pressed wood products made using adhesives that contain urea-formaldehyde (UF) resins. High concentrations may trigger attacks in people with asthma. There is evidence that some people can develop a sensitivity to formaldehyde. It has also been shown to cause cancer in animals and may cause cancer in humans.

If you experience adverse reactions to formaldehyde, you should avoid the use of pressed wood products and other formaldehyde-emitting goods. Even if you do not experience such reactions, you may wish to reduce your exposure as much as possible by purchasing exterior-grade products, which emit less formaldehyde. Some studies suggest that coating pressed wood products with polyurethane may reduce formaldehyde emissions.