Indoor Air Quality

Indoor Air Pollutants and Health 

Indoor air quality can have a profound effect on a person's well being when we spend much time indoors as we do in modern society. The quality of indoor air is impacted by many sources of air pollutants as well as by building construction and ventilation.

There are many sources of indoor air pollutants. The presence of indoor air pollutants such as tobacco smoke and radon, or by conditions that promote poor indoor air quality such as inadequate ventilation or moisture intrusion that can lead to mold growth, are used as indicators of potential health effects. 

Levels of fine particles, carbon monoxide, nitrogen and sulfur oxides, volatile organic compounds (VOCs), radon, and biological contaminants such as certain molds and dust mites are often higher indoors than outdoors. 

Some sources of indoor air pollutants are regulated such as tobacco smoking in public buildings. However, there are no standards that regulate the levels of most indoor air pollutants allowed in buildings or homes. 

Health

Fine particles formed from the combustion of wood and gas impact the lungs and heart. 

Carbon monoxide affects the heart and reduces the ability of blood to carry oxygen to body tissues. 

Nitrogen dioxide is a respiratory irritant and decreases immune and respiratory protective responses. 

Sulfur dioxide is an upper airway irritant, but in combination with fine particles irritates the lung as well. 

Smoking tobacco indoors is a major source of combustion particles and irritant gases. 

Gas cooktops and ovens and room-vented gas or kerosene heaters are major sources of combustion gases, particularly carbon monoxide, nitrogen oxides, and sulfur oxides.

VOCs (which includes formaldehyde) can irritate eyes and the respiratory tract and can also impact the nervous system. Sources of VOCs indoors include paint, cleaning and polishing products, plastics, and composite wood products used in construction. 

The very young and the old as well as people with existing heart and lung diseases (including asthma) are especially sensitive to indoor air contaminants. A large number of known asthma triggers are found indoors. Some mold exposures can result in serious infections in immune-compromised people. 

Conditions that contribute to mold growth in buildings include moisture intrusion and inadequate ventilation to remove normal indoor moisture. 

Measures to reduce indoor air pollutants include adequate ventilation, reduction of indoor tobacco smoking, proper venting of combustion appliances, use of low VOC emitting cleaners, paints, and building materials, and moisture control in buildings. 

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