Awareness: Occupational Asthma

Occupational Asthma

According to the United States Occupational Safety & Health Administration (OSHA), over 100 million workers across a wide range of industries “are exposed to at least one of the numerous agents known to be associated with occupational asthma” [1] and up to 15% of overall asthma cases may be work-related.

“Occupational Asthma” (or work-related asthma) is essentially the same as “Asthma”, except it develops as a result of workplace irritants. describes it as “asthma that’s caused or worsened by breathing in a workplace irritant, such as chemical fumes, gases or dust. Like other types of asthma, occupational asthma can cause symptoms, such as chest tightness, wheezing and shortness of breath.” [2] Occupational asthma can be triggered in more than one way:

Allergic Asthma

In this case, asthmatic symptoms occur because the body develops an allergy to a certain substance. Once the body deems the substance a threat, it begins producing antibodies to defend itself. This process also releases chemicals like histamine and leukotrienes, which causes contractions in the lungs and the narrowing of the air passage (asthmatic symptoms). [3] [4]

Irritant-Induced Asthma

This kind of Occupational Asthma is the result of repeated exposure to a substance, but instead of an allergic reaction, this kind of asthma is a result of direct irritation of the lungs by a substance or chemical. Research shows that antibodies don’t seem to be involved in this case. [4]

Reactive Airways Dysfunction Syndrome

Sometimes asthmatic symptoms can occur rather quickly (within 24 hours) after being exposed to a high concentration of an irritating substance. One of the characteristics of this syndrome is that the same symptoms can come back whenever the person is re-introduced to the irritant. This can continue for months or years. The Canadian Centre for Occupational Health and Safety (CCOHS) explains that this syndrome remains controversial because of lack of solid research. [3]

Characteristics that define Occupational Asthma might include symptoms that get better when you leave work (on the weekends or vacation) and return when you return to work or as the workweek progresses. However, symptoms vary from person to person and can appear after a few minutes of being exposed to a substance or after several years of being exposed to an irritant.

Potential Causes explains that over 300 workplace substances have been identified as potential causes of occupational asthma. They list several of these on their website:

Animal substances, such as proteins found in dander, hair, scales, fur, saliva and body wastes.
Chemicals, such as anhydrides, diisocyanates and acids 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, flour conditioners, some pharmaceuticals and meat tenderizers.
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, welding smoke, and solder smoke

For additional information on identified workplace irritants, Click Here (CCOHS). also provides a list of “high-risk occupations” on their website:

Adhesive handlers– Chemicals such as acrylate
Animal handlers, veterinarians– Animal proteins
Bakers, millers– Cereal grains
Carpet makers– Gums
Electronics workers– Soldering resin
Forest workers, carpenters, cabinetmakers– Wood dust
Hairdressers– Chemicals such as persulfate
Health care workers– Latex and chemicals such as glutaraldehyde
Janitors, cleaning staff– Chemicals such as chloramine-T
Pharmaceutical workers– Drugs, enzymes
Seafood processors– Seafood
Shellac handlers– Chemicals such as amines
Solderers, refiners– Metals
Spray painters, insulation installers, plastics and foam industry workers– Chemicals such as diisocyanates
Textile workers– Dyes
Users of plastics, epoxy resins– Chemicals such as anhydrides (


The United States Occupational Safety & Health Administration standard related to Occupational Asthma:

“Section 5(a)(1) of the OSH Act, often referred to as the General Duty Clause, requires employers to ‘furnish to each of his employees employment and a place of employment which are free from recognized hazards that are causing or are likely to cause death or serious physical harm to his employees’. Section 5(a)(2) requires employers to ‘comply with occupational safety and health standards promulgated under this Act’. “[5]

For more details regarding this OSH act, Click Here.

*Sentry Air Systems, Inc. provides this information as a customer service, but cannot be responsible for its accuracy or completeness. It is recommended that competent legal authorities as well as safety and hygiene professionals be consulted.

Air Quality Assistance

If you believe that your place of business needs air quality improvement to help prevent Occupational Asthma, please call one of our Applications Specialists at 800.799.4609 or email us at Sentry Air Systems specializes in fume extractors and source capture units designed to protect workers and their respiratory region.

Helpful Resources

[1] United States Occupational Safety & Health Administration (OSHA), “Occupational Asthma”:

[2], “Occupational Asthma”:

[3] Canadian Centre for Occupational Health and Safety, “Occupational Asthma”:

[4], “Occupational Asthma: Causes”:

[5] United States Occupational Safety & Health Administration, “Occupational Asthma: OSHA Standards”,, “Occupational Asthma”:

American Academy of Allergy Asthma & Immunology, “Occupational Asthma”: