Occupational asthma

Overview

Asthma is a condition in which your airways narrow and swell and may produce extra mucus. Occupational asthma is a type of asthma. It occurs when you breathe in chemical fumes, gases, dust or other substances on the job. When that happens, it causes an allergic or immunological response.

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 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 changes to your lungs.

Symptoms

Occupational asthma signs and symptoms may include:

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

Other possible 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 medical treatment right away 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 a quick-relief inhaler
• Shortness of breath even with minimal activity

Make an appointment to see your health care provider 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 400 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 and make it difficult to breathe. With occupational asthma, lung inflammation may be triggered by an allergic response to a substance, which usually develops over time. 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 genes that make it more likely for you to develop 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 changes to your lungs.

Prevention

The best way to prevent occupational asthma is to control exposure to chemicals and other substances that that workers may be sensitive to or that are irritating. Workplaces can implement better control methods to prevent exposures, use less harmful substances and provide personal protective equipment (PPE) for workers.

Medications may help relieve symptoms and control inflammation associated with occupational asthma. But you can do several things on your own to maintain overall health and lessen the possibility of attacks:

• If you smoke, quit. 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 with obesity, 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 MSDS to your health care provider.

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.