Indoor Air Quality:
Know the Asthma Triggers in the Home

Asthma attacks can be triggered by things found in the home. Through specific management methods, the impact the triggers have on individuals can be lessened. Always consult medical professionals beforehand, and follow their recommendations.

Shirley M. Niemeyer, Extension Specialist, Housing and Environment

Asthma is a serious lung disease and is the leading cause of long-term illness in children. By 2020, asthma is expected to strike 1 in 14 Americans and 1 in 5 families, according to a National Health Interview Survey conducted by the National Center for Health Statistics in 2001.

In addition:

  • Asthma is the number one cause of school absences attributed to chronic illnesses, with 14 million school days lost per year1.
  • Asthma ranks third as the cause of hospitalization among children age 15 and under2.
  • The health consequences of asthma each year in the U.S. include over 5,000 deaths, 479,000 hospitalizations, and 100 million days of restricted activity.
  • The cost to the U.S. economy is about $14 billion each year3.


1Pew Environmental Health Commission, May 2000 2Centers for Disease Control and Prevention. Surveillance for Asthma – United States, 1980-1999 3National Heart, Lung and Blood Institute, 2002

Not all asthma triggers are listed is this publication. Consult with a health professional for more information about asthma, potential triggers, and how to manage specific problems. The information contained here is not a substitute for professional medical help or your doctor’s recommendations.

Common Asthma Triggers Found in the Home

The National Academy of Sciences (NAS) has found a causal relationship between the development of asthma and house dust mites. It also has found that asthma worsened for sensitized persons exposed to:

When allergens and irritants are found in homes, asthma attacks may be triggered. People may reduce their risk of an asthma attack, prevent asthma from getting worse, and perhaps avoid the onset of asthma entirely by controlling their physical environment. Some common household triggers and methods that can be used to manage them are discussed below.

Secondhand Smoke

Environmental tobacco smoke, or secondhand smoke, may aggravate symptoms in children with asthma, and may contribute to the development of asthma in children. Children exposed to secondhand smoke also are more likely to suffer from pneumonia, bronchitis, and other lung diseases, as well as ear infections. Children whose mothers smoked during pregnancy tend to be born with smaller airways, which increases their chances of developing asthma.

Management Methods

Combustion Products

Combustion products such as soot and smoke, and gases such as sulfur dioxide and nitrogen dioxide can cause breathing problems in children with asthma.

Management Methods


Dust contains more than 5,000 ingredients, including fibers, dander, soil, bacteria, molds, smoke residues, pesticides, dust mite allergens, skin flakes, and insect body parts.

Management Methods

Dust Mites

Dust mites are microscopic creatures and one of the principal irritants in house dust. They live in warm, humid places and in soft furnishings such as mattresses, pillows, carpets, fabric-covered furniture, bedcovers, clothes, and stuffed toys. They are difficult to control.

Management Methods


Animal skin flakes, urine, and saliva can be asthma triggers. Cats and rodents are more likely to be triggers than dogs.

Management Methods


Molds are microscopic fungi that live on plant or animal matter. Growth is encouraged by warm and humid conditions — above 60 percent relative humidity. Molds are naturally occurring and are found both indoors and outdoors. Certain molds may be toxic to some people. Mold should be handled with respect due to the potential health risk.

Management Methods

First control moisture. Reduce humidity to between 35 percent and 50 percent. Use dehumidifiers.

Household members, especially infants and sensitized persons, should not be present during cleanup. Wear gloves, protective clothing, and an air filter mask, or hire a professional to reduce the risk. Work in a well-ventilated area. Using a general purpose cleaner (such as borax) and water, clean the mold from hard surfaces, trying not to spread the spores. Thoroughly dry the area. Carefully discard small amounts of wet or moldy absorbent materials such as ceiling tiles, soft furnishings, and carpet. Before removal, wrap the items in plastic to seal and avoid spreading spores.

Insects and Rodents

Exposure to household pests such as cockroaches and rodents can trigger asthma in some individuals. Many people with asthma are allergic to the dried droppings and cast off skins of cockroaches.

Management Methods


Typical pollens to which people are allergic include grasses, ragweed, and pine, birch, and oak trees. Pollens enter through doors, windows, and other home openings.

Management Methods

Volatile Organic Compounds

Volatile organic compounds (VOCs) are emitted or given off as gases from certain solids or liquids. They are found in items such as building materials, paints, glues, pesticides, solvents, and cleaners. They also can be found in scented products, perfumes, and other personal care items. Formaldehyde found in building materials is an example of a VOC.

Management Methods

Other Potential Asthma Triggers

There are many other asthma triggers. Personal care products, air fresheners, other scented products, and perfumes may be triggers for some people.

Some mechanical air cleaners intentionally give off ozone. Ozone is a lung irritant and may aggravate asthma. It increases the risk of harmful respiratory effects, especially in children.

People with asthma should work with their physician and health care professionals to determine specific pollutants that trigger asthma, how to reduce the triggers, and how to manage their asthma.


Indoor air pollutants can trigger asthma attacks and may lead to its onset. Totally eliminating triggers may be unrealistic, but certain management methods may help control the trigger. The effectiveness of management methods depends on the pollutant source, how significant of an asthma trigger it is for a particular individual, medical recommendations, and feasibility of control.

The following are steps to manage pollutants. They are listed in order of effectiveness after medical recommendations.

  1. Identify and reduce the pollutant at the source. Control pests’ habitat, create barriers to entry, and do not bring pollutants into the home.
  2. Ventilate — mix or dilute pollutants with fresh outside air. Exhaust pollutants.
  3. Evaluate air cleaners by the type and percentage of air particles removed, and the volume of air filtered during a specific time period. Air cleaners are generally not designed to remove gases, although those with charcoal will remove some but will need careful maintenance.


American Academy of Allergy, Asthma, & Immunology — http://www.aaaai.org

American Academy of Pediatrics — http://www.aap.org

American Lung Association — http://www.lungusa.org

Centers for Disease Control and Prevention — http://www.cdc.gov/asthma/

National Academy of Sciences Asthma Report. Clearing the Air 2000.

National Asthma Education and Prevention Program — http://www.nhlbi.nih.gov

U.S. Environmental Protection Agency — http://www.epa.gov/iaq


The author thanks Sarah Morgan, Nebraska Department of Health and Human Services; Lorene Bartos, Susan Hansen, and Pat Jones, UNL extension educators for their contributions to this publication.

This publication is a part of the UNL Extension Healthy Homes program. It was originally developed by Shirley Niemeyer, Dave Keith, and David Morgan, UNL Extension Specialists; and Sharon Skipton, Susan Hansen, George Haws, Rebecca Versch, Mary K. Warner, and Carroll Welte, UNL Extension Educators.

This publication has been peer reviewed.

Visit the University of Nebraska–Lincoln Extension Publications Web site for more publications.
Index: Safety/Health
Indoor Air Quality
Issued May 2011

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