What to know
Summary
May is Asthma Awareness Month. It is a timely reminder of work-related asthma, which is triggered or caused by irritant and allergic exposures in the workplace. There are more than 300 workplace substances that can cause new asthma and many more that can worsen it. These workplace substances include common exposures like cleaning products, mold, and wood dust. Symptoms can appear soon after exposure or months or years after repeated exposure. Symptoms include wheezing, coughing, chest tightness, and shortness of breath that often improve when away from work. If not recognized and appropriately managed, work-related asthma can cause severe symptoms, greater medication use and disability, and even death.
Why work-related asthma matters
In a recent study, an estimated 12.7 million U.S. working adults had asthma in 2020–2021. Forty percent of those workers reported an asthma attack or episode and 8.6% reported an emergency room or urgent care visit for asthma within the last year. Roughly 1.2 to 1.5 million workers' asthma cases were estimated to be work-related.
Workplaces are affected differently
Because there are differences across industries and job types, focused prevention efforts are crucial in jobs where asthma impacts workers the most. Workers in the administrative support, waste management, remediation industry, and in community and social services jobs had the highest prevalence of asthma. Workers in the accommodations and food services industry, and in food preparation and serving jobs, had the most asthma-related emergency room and urgent care visits.
Emerging industries can bring new respiratory risks
A 2025 paper identified 30 work-related asthma cases from four states in the legalized cannabis industry through 2023. Most cases involved indoor cultivation or processing workers and plant materials were the most frequently reported exposure. Importantly, the case series included two fatalities. Study results concluded that cannabis workers are at risk for work-related asthma and that interventions could address hazardous respiratory exposures in the workplace. Early recognition and appropriate disease management are crucial to improving outcomes.
Recognizing asthma might be work-related
Asthma symptoms are the same whether they are work-related or not. They include wheezing, coughing, chest tightness, and shortness of breath. Workers with work-related asthma often find that their symptoms improve when they are away from work, such as during weekends or vacations. However, some workers don't notice improvement until they are away from work for an extended period of time, such as multiple weeks. If a worker notices that their asthma symptoms are getting worse or if they are experiencing newly developed asthma, they can consult with their healthcare provider. If work-related asthma is a consideration, the employer can potentially help in documenting and reducing or eliminating potentially causative workplace exposures. However, it is important to respect workers' wishes about reaching out to employers. Healthcare providers may consider referring workers to experts in occupational medicine or suggesting consultation with experts in employment law when appropriate.
Common workplace triggers
Work-related asthma is associated with workplace irritants, allergens, and physical conditions. Examples include animal dander, insects and dust mites, cleaning products, wood dust, and vapors from chemicals such as ammonia, bleach, or isocyanates.
Diagnosis and management
Workers can tell a healthcare provider if they suspect their asthma may be related to work. Information about job tasks, materials used, and when symptoms occur are important for fact-finding. Healthcare providers may perform breathing tests such as peak flow readings, spirometry, and methacholine challenge, as well as allergy testing to help diagnose asthma. The most important step in managing work-related asthma is stopping or reducing exposure to the triggers that cause symptoms, along with appropriate medical treatment.
Author information
Katelynn Dodd, MPH, is an epidemiologist in the NIOSH Respiratory Health Division.
Michelle Martin, MS, is a health communication specialist in the NIOSH Respiratory Health Division.
David Weissman, MD, is the director of the NIOSH Respiratory Health Division.
Jennifer Flattery, MPH, is an epidemiologist in the California Department of Public Health Occupational Health Branch.
Justine Lew Weinberg, MSEHS, CIH, is an industrial hygienist in the California Department of Public Health Occupational Health Branch and Public Health Institute.
Videos
The Faces of Work-related Asthma video series includes testimonials from an occupational pulmonologist and workers with work-related asthma.