Particulates in Indoor Air

“Particulate” is a general name given to a tiny solid or liquid particle or piece of matter. It usually refers to particles in the air (airborne particulates). Natural sources include soil, plants, fires, and road dust. Human-made sources include:

  • Fumes from combustion processes and products—such as tobacco smoke, car exhaust, power plants, wood stoves, oil burners, or other heating systems. Burning candles or oil in lanterns can also be sources of particulates.
  • Dust from mechanical processes—such as grinding or sweeping—and common household dust that may include mold, pollen, and small insect parts. Fibrous building material such as fiberglass may also be a source of particulates.
  • Mist—such as that caused by spray painting.

In general, the smaller and lighter a particulate is, the longer it will stay in the air. A fairly dense particulates—such as lead dust—are likely to stay in the air for a shorter period of time than other particulates. Some particulates—such as certain types of fibers or pollen—may stay in the air for very long periods of time, especially if there is air movement caused by occupants, pets, open windows, fans, office equipment, vacuum cleaners, etc.

EXPOSURE TO PARTICULATES

In order for particulates to pose a health risk, a person must be exposed in such a way that the particulates are drawn into the body. Sometimes, as in childhood lead poisoning, this exposure is through hand-to-mouth behavior in which the lead dust is swallowed. In most instances, however, exposure comes from inhaling airborne particulates.

The size of the particulate often determines where in the body the particle may come to rest and possibly cause health effects. For example, if pollen enters into the breathing zone, it may be captured in the nose or upper airways. The mucous and tiny hairs that line those body airways can capture the pollen, preventing it from entry into the lungs. Smaller particles—such as silica, tobacco smoke, lead, some materials used in office equipment, and combustion byproducts—get past the nose and upper airways and are deposited in the lungs.

Health Effects of Exposure to Particulates

The health effects can range from none at all to very serious. For people with allergies, certain types and amounts of particulates—such as mold spores, pet dander, pollen, or dust mites, may cause allergic reactions. Some people can be allergic to material in tobacco smoke and other combustion byproducts. Examples of allergic symptoms and signs include nasal discharge, difficulty breathing, coughing, runny eyes, throat irritation, rashes, and headaches. In severe allergic reactions, death can occur. Asthmatic episodes may occur in some people with asthma.

Some particulates—such as silica, asbestos fibers, and coal dust—can cause permanent lung damage, with symptoms and signs like coughing, chronic shortness of breath, and fatigue. When inhaled in high enough doses, lead dust can be a major source of lead poisoning in adults who engage in certain activities such as painting and building renovation. It can cause high blood pressure, decreased hearing, reproductive problems, and even death. Tobacco smoke, which contains numerous toxic materials in particulate form, can cause chronic obstructive pulmonary disease (COPD)—such as emphysema and lung cancer.

More Information

  • Product information—contact the makers of filters and equipment such as vacuums, respirators, air cleaners, dehumidifiers, and HVAC (heating, ventilating, and air conditioning) systems
  • Indoor Air Quality