Indoor Air Can Cause Health Problems

By Beans, Bruce E. 
March 21, 2017

Indoor Air Can Cause Health Problems

Are you worried about the air you breathe? Don't think you're safe just because you're inside. The Environmental Protection Agency (EPA) says that the air in homes and other buildings can be more seriously polluted than the outdoor air.

Indoor air pollution can cause big health problems. People who may be exposed to indoor air pollutants for the longest periods are often those most at risk to the effects of indoor air pollution. This includes children, older adults, and people with chronic illnesses.

Most indoor air pollution comes from sources that release gases or particles into the air. Things like building materials and air fresheners give off pollution continuously. Other sources like tobacco smoke and wood-burning stoves also cause indoor pollution. Although some indoor air pollutants have been around for years, they often were weakened by outdoor air seeping into the home. Today's more energy-efficient homes don't allow as much outdoor air to enter.

Indoor air hazards

Ozone generators are sold as air cleaners and make ozone gas on purpose. But, high concentrations of ozone react with organic material inside and outside the body. When inhaled, ozone can damage the lungs. This can cause chest pain, coughing, shortness of breath, and throat irritation. It can make chronic lung diseases like asthma worse and increase the risk for lung infections.

The EPA says that research does not support claims that ozone from these devices removes dust, pollen, and chemicals from the air. No federal agency has approved these devices as air cleaners. The official number found on ozone generator packaging is only the identification of the facility that made the product. It is not an approval number.


Other common sources of indoor pollution include:

Live sources

These include mold, mildew, cockroaches, and dust mites.

Carbon monoxide (CO)

CO and other pollutants are released from fuel-burning stoves, heaters, and other appliances. CO is an odorless, colorless gas. It blocks the movement of oxygen in the body. Depending on how much is breathed in, CO can affect coordination, make heart conditions worse, and cause extreme tiredness, headache, confusion, nausea, and dizziness. Very high levels can cause death. Older adults, babies, and people with heart and lung diseases are even more  sensitive to elevated CO levels.

Nitrogen dioxide

This is a product of natural gas and kerosene combustion. Like CO, it is odorless and colorless. It irritates the mucous membranes of the eyes, nose, and throat and causes shortness of breath in high concentrations. Long-term exposure to nitrogen dioxide can damage the lungs and may lead to chronic bronchitis. Exposure to low levels may worsen symptoms in people who have asthma, chronic obstructive pulmonary disease, and increase other respiratory infections.

Sulfur dioxide

This gas is a product of burning kerosene in a space heater. It is very irritating to the eyes and upper respiratory tract.


Radon is a radioactive gas that seeps from the soil and rocks beneath your home. Radon can enter a home through cracks in the foundation, walls, drains, and other openings. Exposure to radon in the home is the second leading cause of lung cancer. Smoking is the first. Smokers and former smokers exposed to radon may have a much higher risk of death from lung cancer.

Secondhand smoke

Cigarette smoke contains trace amounts of about 4,000 chemicals, including 200 known poisons like formaldehyde and carbon monoxide, and 43 carcinogens.

These are other common household air pollutants:

  • Particulates like dust and pollen.

  • Formaldehyde, a common preservative and adhesive in furniture, carpets, drapes, particleboard, and plywood paneling. Breathing formaldehyde fumes can cause coughing, irritation of the eyes, nose and throat, rashes, headaches, and dizziness.

  • Household products like personal care products, pesticides, household cleaners, solvents, and chemicals used for hobbies. Exposure to these products can cause dizziness, nausea, allergic reactions, irritation of eyes, skin, and lungs, and cancer. Certain cleaning products can produce poisonous fumes. Never mix chlorine bleach and ammonia.

  • Remodeling hazards like new carpeting and paint. These can give off fumes that irritate the eyes, nose, and throat.

  • Asbestos, from insulation, floor tiles, spackling compounds, cement, and heating equipment. These products can be a problem indoors only if the material that contains the asbestos is disturbed and becomes airborne. This also happens when the product falls apart with age. Asbestos fibers are light, flexible, and small enough to stay airborne. Because of this, fibers can be breathed in, causing scarring of lung tissue and lung cancer.

  • Lead, which was common in paint made before 1978.

  • Pesticides. Exposure to these can occur through normal use of sprays, strips filled with pesticides, and foggers (also called "bombs"). Exposure can also occur from contaminated dusts after use, especially for children who may be in close contact with contaminated surfaces. Symptoms can include headache, dizziness, muscular weakness, and nausea. Some pesticides may cause cancer.

Signs of air trouble

These symptoms may be a sign of indoor air hazards. They include: 

  • Unusual and noticeable odors, stale or stuffy air.

  • Clear lack of air movement.

  • Dirty or faulty central heating or air conditioning.

  • Damaged flue pipes or chimneys.

  • Excessive humidity. A relative humidity of 30% to 50% is generally recommended for homes. Remove standing water, water-damaged materials, and wet surfaces. These can serve as a breeding ground for molds, mildews, bacteria, and insects.

  • Molds and mildew.

  • Health reaction after remodeling, moving, weatherizing, buying new furniture, or using household or hobby products.

  • Feeling healthier outside the home.

How safe is your air?

In general:

  • Never buy more than you need of products that might add to indoor pollution like cleaning solvents or pesticides.

  • Follow makers' directions for use, storage, and disposal.

  • Provide ample ventilation before and after putting in products like pressed-wood furniture, and carpets or draperies that might give off chemicals.

  • Don't allow smoking in your house.


  • Keep moisture under control. Moisture leads to growth of living pollutants and condensation. Exhaust fans can help.

  • Personal care products and air fresheners can give off gases. Find items with little or no aerosol, open windows, and use fans.

  • Have a professional repair or remove damaged asbestos floor tiles.


  • A cold mist humidifier or vaporizer can promote the growth of living pollutants. Use and clean the appliance properly and change water daily.

  • Bedding should use pillows and mattress covers that block allergens. Wash regularly in water above 130° F (54° C). Vacuum under beds regularly to control dust mites.

  • Dry cleaning can leave gases on clothes. Air them out before taking them indoors. Consider washing by hand instead.

  • Air conditioners harbor living allergens. Clean water trays often and change filters.

Living areas

  • Paneling or pressed-wood furniture may release formaldehyde gas. Seek brands like those with phenol resin that give off less formaldehyde, or seal with polyurethane.

  • Carpets can give off gases when new and host living pollutants when wet. Air out new carpets before installing. Ask for adhesives that give off low amounts of gases. Clean and dry water-damaged carpets or remove them. Vacuum to curb dust mites. Dust mites are an asthma trigger.

  • New draperies may have a formaldehyde-based finish. Air out before hanging.

  • Fireplaces create CO and other combustion pollutants. Open the flue during use. Have the flue and chimney inspected each year.

  • Gas or kerosene space heaters create CO and combustion pollutants. Never use them unless they are properly vented. Open doors to the rest of the house, use an exhaust fan, and open windows slightly.


  • Household cleaners may give off unsafe or irritating vapors. Use nonaerosol, nontoxic products.

  • Moisture from cooking and washing leads to living pollutants. Use exhaust fans.

  • Unvented gas stoves and ranges raise the risks of CO and combustion byproducts. Clean and adjust burners, use exhaust fans, and never use a stove or range to heat a home.


  • Engine exhaust carries CO and combustion byproducts. Never run engines in a garage.

  • Paint and solvents. Air out when using. Reseal containers well. Clean brushes outside.

  • Pesticides and fertilizers. Consider nonchemical methods. Air out if using indoors.

  • Fuels. Store labeled, sealed containers made for fuels outside in a well-ventilated area.

Laundry or utility areas

  • Unvented clothes dryers promote moisture, living pollutants, and dust. Vent dryers to the outside. A gas-fired dryer creates CO and combustion byproducts. Clean lint filters often and provide air for gas combustion.

  • Ground moisture promotes living allergens. Look for condensation on walls, water on floors, or sewage leaks. To keep water out, install gutters and downspouts, don't water near foundations, grade soil away from the house, and waterproof basement walls.

  • Asbestos pipe wrap and furnace insulation should be checked routinely for damage or wear. Have a professional make any repairs.

  • Fossil-fuel furnaces and water heaters pose risks of CO and combustion pollutants. Have them inspected yearly, clean around them often, and change filters regularly. Call your fuel supplier or fire department at once if you suspect a CO or fuel leak.

  • Test for radon. Have an experienced certified contractor from your state or the EPA correct radon levels of 4 picocuries per liter or higher.

For more information on indoor air safety, contact the EPA or your state’s environmental protection agency. 


March 21, 2017


Health & You

Reviewed By:  

Adler, Liora, C., MD,Fetterman, Anne, RN, BSN