Overview

Occupational asthma is asthma that's caused by breathing in chemical fumes, gases, dust or other substances on the job. Occupational asthma can result from exposure to a substance you're sensitive to — causing an allergic or immunological response — or to an irritating toxic substance.

Like other types of asthma, occupational asthma can cause chest tightness, wheezing and shortness of breath. People with allergies or with a family history of allergies are more likely to develop occupational asthma.

Avoidance of occupational triggers is an important part of management. Otherwise, treatment for occupational asthma is similar to treatment for other types of asthma and generally includes taking medications to reduce symptoms. If you already have asthma, sometimes treatment can help it from becoming worse in the workplace.

If it's not correctly diagnosed and you are not protected or able to avoid exposure, occupational asthma can cause permanent lung damage, disability or death.

Symptoms

Occupational asthma symptoms are similar to those caused by other types of asthma. Signs and symptoms may include:

  • Wheezing, sometimes just at night
  • Coughing
  • Shortness of breath
  • Chest tightness

Other possible accompanying signs and symptoms may include:

  • Runny nose
  • Nasal congestion
  • Eye irritation and tearing

Occupational asthma symptoms depend on the substance you're exposed to, how long and how often you're exposed, and other factors. Your symptoms may:

  • Get worse as the workweek progresses, go away during weekends and vacations, and recur when you return to work.
  • Occur both at work and away from work.
  • Start as soon as you're exposed to an asthma-inducing substance at work or only after a period of regular exposure to the substance.
  • Continue after exposure is stopped. The longer you're exposed to the asthma-causing substance, the more likely you'll have long-lasting or permanent asthma symptoms.

When to see a doctor

Seek immediate medical treatment if your symptoms worsen. Severe asthma attacks can be life-threatening. Signs and symptoms of an asthma attack that needs emergency treatment include:

  • Rapid worsening of shortness of breath or wheezing
  • No improvement even after using short-acting bronchodilators
  • Shortness of breath with minimal activity

Make an appointment to see a doctor if you have breathing problems, such as coughing, wheezing or shortness of breath. Breathing problems may be a sign of asthma, especially if symptoms seem to be getting worse over time or appear to be aggravated by specific triggers or irritants.

Causes

More than 250 workplace substances have been identified as possible causes of occupational asthma. These substances include:

  • Animal substances, such as proteins found in dander, hair, scales, fur, saliva and body wastes.
  • Chemicals used to make paints, varnishes, adhesives, laminates and soldering resin. Other examples include chemicals used to make insulation, packaging materials, and foam mattresses and upholstery.
  • Enzymes used in detergents and flour conditioners.
  • Metals, particularly platinum, chromium and nickel sulfate.
  • Plant substances, including proteins found in natural rubber latex, flour, cereals, cotton, flax, hemp, rye, wheat and papain — a digestive enzyme derived from papaya.
  • Respiratory irritants, such as chlorine gas, sulfur dioxide and smoke.

Asthma symptoms start when your lungs become irritated (inflamed). Inflammation causes several reactions that restrict the airways, making breathing difficult. With occupational asthma, lung inflammation may be triggered by an allergic response to a substance, which usually develops over time. Alternatively, inhaling fumes from a lung irritant, such as chlorine, can trigger immediate asthma symptoms in the absence of allergy.

Risk factors

The intensity of your exposure increases your risk of developing occupational asthma. In addition, you will have increased risk if:

  • You have existing allergies or asthma. Although this can increase your risk, many people who have allergies or asthma do jobs that expose them to lung irritants and never have symptoms.
  • Allergies or asthma runs in your family. Your parents may pass down a genetic predisposition to asthma.
  • You work around known asthma triggers. Some substances are known to be lung irritants and asthma triggers.
  • You smoke. Smoking increases your risk of developing asthma if you are exposed to certain types of irritants.

High-risk occupations

It's possible to develop occupational asthma in almost any workplace. But your risk is higher if you work in certain occupations. Some of the riskiest jobs and the asthma-producing substances associated with them include the following:

Jobs Asthma-producing substances
Adhesive handlers Chemicals
Animal handlers, veterinarians Animal proteins
Bakers, millers, farmers Cereal grains
Carpet makers Vegetable gums
Metal workers Cobalt, nickel
Food production workers Milk powder, egg powder
Forest workers, carpenters, cabinetmakers Wood dust
Hairdressers Dyes
Health care workers Latex and chemicals
Pharmaceutical workers, bakers Drugs, enzymes
Seafood processors Herring, snow crab
Spray painters, insulation installers, plastics and foam industry workers, welders, metalworkers, chemical manufacturers, shellac handlers Chemicals
Textile workers Dyes, plastics
Users of plastics or epoxy resins, chemical manufacturers Chemicals

Complications

The longer you're exposed to a substance that causes occupational asthma, the worse your symptoms may become — and the longer it will take for them to improve once you end your exposure to the irritant. In some cases, exposure to airborne asthma triggers can cause permanent lung changes, resulting in disability or death.

Prevention

The best way to prevent occupational asthma is for workplaces to control the workers' level of exposure to chemicals and other substances that may be sensitizers or irritants. Such measures can include implementing better control methods to prevent exposures, using less harmful substances and providing personal protective equipment (PPE) for workers.

Although you may rely on medications to relieve symptoms and control inflammation associated with occupational asthma, you can do several things on your own to maintain overall health and lessen the possibility of attacks:

  • If you smoke, quit. In addition to all its other health benefits, being smoke-free may help prevent or lessen symptoms of occupational asthma.
  • Get a flu vaccination. This can help prevent illness.
  • Avoid nonsteroidal anti-inflammatory drugs (NSAIDS) and other medications that may make symptoms worse.
  • Lose weight. For people who are obese, losing weight can help improve symptoms and lung function.

If you are in the United States and you have a job in a high-risk profession, your company has legal responsibilities to help protect you from hazardous chemicals. Under guidelines established by the Occupational Safety and Health Administration (OSHA), your employer is required to do the following:

  • Inform you if you'll be working with any hazardous chemicals.
  • Train you how to safely handle these chemicals.
  • Train you how to respond to an emergency, such as a chemical spill.
  • Provide protective gear, such as masks and respirators.
  • Offer additional training if a new chemical is introduced to your workplace.

Under OSHA guidelines, your employer is required to keep a material safety data sheet (MSDS) for each hazardous chemical used in your workplace. This is a document that must be submitted by the chemical's manufacturer to your employer. You have a legal right to see and copy such documents. If you suspect you're allergic to a certain substance, show the material safety data sheet to your doctor.

While at work, be alert for unsafe and unhealthy working conditions and report them to your supervisor. If necessary, call OSHA at 800-321-OSHA (800-321-6742) and ask for an on-site inspection. You can do this so that your name won't be revealed to your employer.

May 22, 2018
References
  1. Occupational asthma. Tips to remember. American Academy of Allergy, Asthma & Immunology. http://www.aaaai.org/conditions-and-treatments/library/at-a-glance/occupational-asthma.aspx. Accessed Dec. 29, 2017.
  2. Occupational asthma. American Academy of Allergy, Asthma & Immunology. http://www.aaaai.org/conditions-and-treatments/conditions-a-to-z-search/occupational-asthma. Accessed Jan. 4, 2018.
  3. Anderson SE, et al. Occupational asthma. European Medical Journal. 2017;2:65.
  4. Cartier A, et al. Occupational asthma: Definitions, epidemiology, causes, and risk factors. https://www.uptodate.com/contents/search. Accessed Jan. 1, 2018.
  5. Wong EHC, et al. Asthma: Diagnosis and management in adults. Medicine. 2016:44:287.
  6. Lemière C, et al. Occupational asthma: Clinical features and diagnosis. https://www.uptodate.com/contents/search. Accessed Jan. 1, 2018.
  7. Lemière C, et al. Occupational asthma: Management, prognosis and prevention. https://www.uptodate.com/contents/search. Accessed Jan. 1, 2018.
  8. Bepko J, et al. Common occupational disorders: Asthma, COPD, dermatitis, and musculoskeletal disorders. American Family Physician. 2016;93:1000.
  9. Cullinan P, et al. Occupational lung diseases: From old and novel exposures to effective preventive strategies. The Lancet. 2017:5:445.
  10. Adkinson NF, et al. Occupational allergy and asthma. In: Middleton's Allergy: Principles and Practice. 8th ed. Philadelphia, Pa.: Saunders Elsevier; 2014. https://www.clinicalkey.com. Accessed Jan. 1, 2018.
  11. Fact sheet. Do you have work-related asthma? Occupational Safety and Health Administration. https://www.osha.gov/pls/publications/publication.athruz?pType=Types&pID=2. Accessed Jan. 1, 2018.
  12. Jolly AT, et al. Work-related asthma. Journal of Occupational and Environmental Medicine. 2015:57:e121.
  13. Expert panel report 3: Guidelines for the diagnosis and management of asthma. National Heart, Lung, and Blood Institute. National Asthma Education and Prevention Program. Full Report 2007.
  14. 2017 GINA Report, Global Strategy for Asthma Management and Prevention. Global Initiative for Asthma (GINA). www.ginasthma.org. Accessed Jan. 11, 2018.
  15. AAAAI Allergy and asthma drug guide. American Academy of Allergy, Asthma & Immunology. http://www.aaaai.org/conditions-and-treatments/treatments/drug-guide. Accessed Jan. 14, 2018.
  16. What are asthma symptoms? Asthma and Allergy Foundation of America. http://www.aafa.org/page/asthma-symptoms.aspx. Accessed Jan. 14, 2018.
  17. Tarlo SM, et al. Occupational asthma. New England Journal of Medicine. 2014;370:640.
  18. Asthma in depth. National Center for Complementary and Integrative Health. https://nccih.nih.gov/health/asthma/facts. Accessed Jan. 23, 2018.
  19. Rakel D, ed. Asthma. In: Integrative Medicine. 4th ed. Philadelphia, Pa.: Elsevier; 2018. https://www.clinicalkey.com. Accessed Jan. 23, 2018.
  20. Training requirements in OSHA standards (OSHA 2254-09R-2015). Occupational Safety and Health Administration. https://www.osha.gov/pls/publications/publication.AthruZ?pType=AthruZ#T. Accessed Jan. 11, 2018.
  21. Hazard communication standards: Toxic and hazardous substances (1910.1200). Occupational Safety and Health Administration. https://www.osha.gov/pls/oshaweb/owadisp.show_document?p_id=10099&p_table=STANDARDS. Accessed Jan. 11, 2018.
  22. General requirements: Personal protective equipment (1910.132, subpart I). Occupational Safety and Health Administration. https://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=STANDARDS&p_id=9777. Accessed Jan. 11, 2018.
  23. Hazardous waste operations and emergency response: Hazardous materials (1910.120, subpart H). Occupational Safety and Health Administration. https://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=STANDARDS&p_id=9765. Accessed Jan. 11, 2018.
  24. Hazard communication: Steps to an effective hazard communication program for employers that use hazardous chemicals fact sheet. Occupational Safety and Health Administration. https://www.osha.gov/pls/publications/publication.AthruZ?pType=AthruZ#S. Accessed Jan. 11, 2018.
  25. Li JT (expert opinion). Mayo Clinic, Rochester, Minn. Feb. 2, 2018.