Occupational Asthma: Causes, Diagnosis, and Treatment

Occupational asthma, also called work-related asthma, is a lung disease that occurs when an individual is exposed to certain chemicals, irritants, or allergens in the workplace. The biggest difference between occupational asthma and other types of asthma is that it can usually be reversed when exposure to workplace irritants stops.

This article details the various types of occupational asthma irritants, some of the most at-risk jobs, treatment, and prevention.

Examples of Occupational Asthma

There are three common causes of occupational asthma: allergic reactions, irritant reactions or "irritant-induced occupational asthma" (II-OA), and buildup of chemicals or "sensitizer-induced occupational asthma" (SI-OA), which eventually cause asthma attacks.

Healthcare: Asthma Caused by Latex Allergy

Healthcare workers may develop occupational asthma from inhaling the dust particles of latex gloves or other latex objects.

Chemical Industry: Asthma Caused by Irritants

Irritant-induced occupational asthma is caused by a variety of chemical agents including:

• Gases: Chlorine, sulfur dioxide, nitrogen oxides
• Acids: Acetic, hydrochloric, hydrofluoric
• Alkali: Ammonia, calcium oxide, hydrazine
• Biocides: Ethylene oxide, fumigating agents, insecticides
• Halogenated derivatives: Uranium hexafluoride, hydrogen, and carbonyl fluoride
• Solvents: Perchloroethylene
• Fumes: Diesel exhaust, paint fumes, fire smoke
• Sprays: Paints, floor sealant
  

Textile Industry: Asthma Caused by Flax, Cotton, and Hemp Dust

Textile workers may develop occupational asthma by inhaling dust from flax, cotton, and hemp. The dust particles can cause irritation and inflammation in the lungs and induce an allergic reaction.

Agricultural Workers: Asthma Caused by Buildup of Insecticides

When inhaled over time, the particles that make up insecticides can damage the lining of the airways and trigger an allergic reaction.

Who Is At Risk

Individuals who are regularly exposed to common asthma triggers at work are at an increased risk for developing occupational asthma. Substances that can trigger occupational asthma include:

• Wood dust
• Grain dust
• Animal dander
• Fungi
• Chemicals
  

Workers At Increased Risk

Workers most likely to be exposed to one or more of these triggers include:

• Bakers
• Detergent manufacturers
• Drug manufacturers
• Farmers
• Grain elevator workers
• Laboratory workers (especially those working with laboratory animals)
• Metal workers
• Millers
• Plastics workers
• Woodworkers
  

Diagnosing and Treating Occupational Asthma

Occupational asthma is often under-diagnosed. One 2019 study looked at a population of 50,000 workers with asthma. They found that only 11.7% of people had ever told their healthcare provider that their asthma was related to work, and only 9.1% of people learned that their asthma was work-induced from their healthcare provider.

According to the Centers for Disease Control and Prevention (CDC), approximately 17% of adult asthma cases are related to occupational exposures.

Symptoms of Occupational Asthma

The symptoms of occupational asthma often look the same as other kinds of asthma. They can include:

• Coughing
• Wheezing
• Shortness of breath
• Tightness in chest

How Do I Know If My Asthma Is Work-Related?

You will not know for sure if your asthma is work-related until you meet with your healthcare provider or an allergist for an evaluation.

A healthcare provider or allergist will perform a physical exam to determine your lung function. Then they will ask you about your medical history as well as the symptoms you're currently experiencing.

You can expect them to ask detailed questions about your work environment and potential allergens. They'll want to know about the timing of your asthma symptoms, and they might even ask how you feel when you're not at work.

Occupational Asthma vs. Bronchitis

It can be tricky to tell the symptoms of occupational asthma and bronchitis apart. They both come with coughing, wheezing, and shortness of breath.

However, bronchitis may go away on its own after a few days or weeks, whereas occupational asthma does not go away until the allergen is removed. If you have a cough that lasts for months and comes back more than two years in a row, it could be chronic bronchitis.

When to See a Doctor

If you think you might have occupational asthma, make an appointment with your healthcare provider as soon as you can. For asthma symptoms that do not get better with the use of a rescue inhaler, or lead to difficulty breathing or blue or purple lips or fingernails, seek immediate medical attention.

What to Do About Occupational Asthma

Treatment

Most allergists will work with their asthma patients to develop an asthma treatment plan. This usually involves identifying and avoiding asthma triggers, and using a rescue inhaler for asthma attacks. Treatment for occupational asthma is the same.

Complications

Occupational asthma can be misdiagnosed or simply go untreated. This can mean years of exposure to an irritant, which can lead to permanent lung damage.

Prevention

Ideally, preventing occupational asthma starts at the employer level by avoiding common asthma-inducing substances. But this isn't always possible, depending on person's employment and financial needs.

Ongoing screening is another level of prevention that employers may use to help identify whether occupational asthma is prevalent among their employee population.

Discuss your diagnosis with your employer to determine options for removing or minimizing your exposure to your occupational asthma triggers. By law, your employer is required to make reasonable accommodations so that you may continue to work. This could be as simple as a healthcare worker swapping out latex gloves for a hypoallergenic alternative.

Summary

Occupational asthma is asthma induced by a person's workplace environment. It spans industries, from agriculture to healthcare and many others in between. The symptoms can be confused with other lung diseases such as bronchitis.

If you have asthma symptoms such as coughing, wheezing, and shortness of breath at work, but feel better on the weekends or vacations, talk to your healthcare provider about occupational asthma.

A Word From Verywell 

Fortunately, occupational asthma is usually reversible if the workplace irritant is removed. Most employers are willing and able to work with people who have occupational asthma to eliminate the exposure, or to make reasonable accommodations to ensure they are not putting their employees at unnecessary risk. There's no reason to brush off your asthma symptoms or fear speaking up about how they're affecting you at work.