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Building-Related Illnesses


Carrie A. Redlich

, MD, MPH, Yale Occupational and Environmental Medicine Program Yale School of Medicine;

Efia S. James

, MD, MPH, Yale School of Medicine;

Brian Linde

, MD, MPH, Yale Occ and Env Medicine Program

Reviewed/Revised Oct 2023

In industrialized countries, people spend > 90% of their life (about 22 hours per day) indoors. Symptoms and illnesses related to indoor environments are common and can substantially impact health. It is important that clinicians recognize when symptoms are related to the indoor environment so that, where possible, exposures can be decreased or eliminated.

Building-related illnesses are a heterogeneous group of disorders associated with a particular building or indoor environment. In some cases, a discrete causative agent can be identified, but often identification is not possible because symptoms and illness are rarely caused by a single exposure. Most building-related illnesses are related to more than one type of exposure combined with inadequate ventilation.

Ventilation is exchanging indoor air with outdoor air to create a comfortable environment. Poor ventilation can lead to the accumulation of indoor pollutants, such as dust, mold, allergens, secondhand smoke, cleaning products, perfumes, volatile organic compounds, and other chemicals. Outdoor air pollution, infectious agents, and bioaerosols can also contribute to indoor exposures.

In addition to ventilation-related problems, temperature and humidity are important factors. Damp indoor environments and excessive moisture, such as from leaks and floods, favor the growth of molds and other microbial agents, which are among the most common sources of building-related symptoms and illness.

Specific building-related illnesses

Specific building-related illnesses are associated with a particular building or indoor environment and meet condition-related diagnostic criteria. These illnesses can vary in severity and acuity. Examples include

Nonspecific building-related symptoms

Building-related symptoms are symptoms that occur in association with a specific indoor environment but are not easily categorized as a single definable illness. The term sick building syndrome has been used to refer to illnesses that occur in clusters within a building, but this term is being replaced by the term building-related symptoms.

Commonly reported building-related symptoms include

  • Itchy, irritated, dry, or watery eyes

  • Rhinorrhea or nasal congestion

  • Throat soreness or tightness

  • Cough and chest congestion

  • Dry, itchy skin or unexplained rashes

  • Headache, lethargy, or difficulty concentrating

The above symptoms should prompt consideration of the possibility of an indoor environmental exposure.

Diagnosis of Building-Related Illness

  • Evaluation of patient factors

  • Workplace evaluation

Patient evaluation

The diagnosis of building-related illness is based on the exposure history and clinical findings (including symptom onset, timing, and progression). Increased use of medications, medical visits, and sick days used should be documented.

Symptoms that are temporally associated with a specific building or environment and that improve when the patient is away from the environment is an important clue that should be noted. As in any other clinical encounter, specific illnesses, such as asthma Asthma Asthma is a disease of diffuse airway inflammation caused by a variety of triggering stimuli resulting in partially or completely reversible bronchoconstriction. Symptoms and signs include dyspnea... read more or hypersensitivity pneumonitis Hypersensitivity Pneumonitis Hypersensitivity pneumonitis is a syndrome of cough, dyspnea, and fatigue caused by sensitization and subsequent hypersensitivity to environmental (frequently occupational or domestic) antigens... read more Hypersensitivity Pneumonitis , should be ruled out. Further evaluation should be based on symptoms. For example, pulmonary function tests may be informative in exposed patients when they are symptomatic.

The exposure assessment includes a description of the work and other environments the patient frequents, including the size of the space, number of workers, ventilation, job tasks, and potential sources of exposure such as dust, chemicals, gases, cleaning products, mold, and other microbial agents. The patient should be asked about any changes in the workplace or work processes that may coincide with onset or exacerbation of symptoms. Similar symptoms in other occupants of the building, though not always present, can be a clue to building-related illness.

Commonly encountered building settings include offices, schools, restaurants, entertainment venues, and healthcare facilities. Recent renovations, refurnishing, or construction should be documented and evaluated as a potential source of exposure.

Workplace evaluation

A workplace evaluation can be helpful in identifying contributing factors to building-related illness or symptoms. A workplace evaluation helps to identify potential exposures, such as water incursion, mold, dust, odors, and temperature extremes, as well as to get a sense of the overall indoor environmental quality, including ventilation and fresh air intake. Sources of information about the indoor environment include the employer, previous workplace evaluations, safety data sheets, previous environmental monitoring reports, and union representatives.

Extensive air and surface sampling, such as for mold, is generally not necessary and is often costly. Most building-related illnesses are related to more than one exposure combined with inadequate ventilation.

Treatment of Building-Related Illnesses

  • Treatment of diagnosed condition

  • Building remediation

Treatment of diagnosed conditions is similar whether the illness is building-related or not.

Remediation of culprit exposures and optimizing the building ventilation are central to managing building-related symptoms and illness.

In the United States, reliable guidance on indoor environmental quality can be obtained through the U. S. Environmental Protection Agency (EPA), the Centers for Disease Control and Prevention National Institute for Health and Safety (CDC-NIOSH), and Department of Public Health websites for individual states.

More Information

The following English-language resources may be useful. Please note that THE MANUAL is not responsible for the content of these resources.

NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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