Baker's Asthma: How Baking Can Impact Lung Health

For many, a bakery is a place of comfort and calm, where heavenly smells fill the air. But few realize that for those who work there, repeated exposure to flour and baking ingredients can pose a serious health risk. Though it may sound like something out of a sci-fi show, when workers are repeatedly exposed to airborne flour dust and other baking allergens, it may cause respiratory problems. This condition, which is considered one of the most common but least discussed occupational respiratory diseases, is called baker’s lung or baker’s asthma.

The first recorded reports of baker’s lung were as early as the 1700s, when shortness of breath, hoarseness, wheezing and eye, nose and throat irritation occurred commonly in bakers. Written off as a consequence of the trade, it wasn’t until the 1970s and 1980s that scientists were better able to measure irritants or allergens in the air and determine that certain common baking ingredients, like wheat flour, grain mites or molds, resulted in extreme irritation of the nose, throat and lung and may lead to a rhinitis, eczema or an asthma diagnosis. Since then, many workplace health and safety measures have been put in place, but baker’s asthma still affects between 7% and 15% of bakers.

What’s Leads to Baker’s Lung? 

Baker’s asthma develops after repeated inhalation of flour dust and other airborne substances commonly found in bakeries. Unlike irritants alone, baker’s asthma is often an irritant and allergic reaction together in which the immune system becomes sensitive to specific proteins. Once sensitization occurs, even small amounts of exposure can trigger symptoms.

The most common causes are:

• Flour and grain dust from wheat, rye, barley, soy or buckwheat
• Fungal alpha-amylase, an enzyme frequently added to flour to improve baking performance
• Other additives and enzymes including eggs, egg powder, sesame/sesame seeds, yeast and nuts
• Storage grain mites and molds

Unfortunately, since workers are often exposed to multiple ingredients at the same time, it can be difficult to pinpoint a single item as the trigger.

How Do I Know if I Have Baker’s Lung? 

In most cases, before workers develop baker’s asthma, they often experience occupational rhinitis or eczema (dermatitis). This may result in cold-like symptoms such as a runny nose, sneezing and congestion. If symptoms are addressed promptly, developing baker’s asthma may be prevented or controlled. If not, people may experience wheezing, persistent cough, chest tightness, shortness of breath and itchy, watery eyes.

Since these are common symptoms, “occupational history and exposure history is important when diagnosing a patient who comes in with wheezing, cough, sputum, production and chest tightness,” pulmonologist Dr. Glenn Singer explained. “It's also instructive to note if the symptoms are better on weekends, for example, if the patient is removed from the exposing agents.” 

Who’s at Risk of Developing Baker’s Lung?

“Usually, prolonged exposure is needed for baker's asthma. Casual home exposure could potentially cause a problem, but that would be less likely,” Dr. Singer continued.  

So, while anyone who regularly works around airborne flour dust can develop the condition, certain occupations are at significantly higher risk. They include:

• Commercial and artisan bakers
• Pastry chefs
• Bakery assistants
• Flour mill workers
• Pizza makers
• Food manufacturing (including pet products) employees
• Supermarket bakery staff

Workers involved in mixing, weighing, pouring or sifting flour have the highest exposure because these tasks generate large amounts of airborne particles. But other factors, like a history of allergic conditions or tobacco use, have also been associated with increased sensitivity.

How Do I Prevent or Control Baker’s Lung?

Luckily, baker’s lung is highly preventable with a few steps of prevention. “Unfortunately, once the condition is diagnosed, it's there,” Dr. Singer said. “While there are treatments, avoidance is the best strategy.” So, eliminating or reducing flour dust is the best way to reduce harm. For individuals working in at-risk industries, preventive measures may include:

• Switching to low-dust products, enclosing storage containers, pouring ingredients gently, mixing slowly and avoiding shaking flour bags can all reduce particles in the air. 
• Improving ventilation with local exhaust fans to vent flour particles to the outside. 
• Using vacuum systems with High Efficiency Particulate Air filters (HEPA) or damp cloths to capture particles safely without sending them back into the air
• Performing regular environmental health and safety checks to ensure machinery is clean and in working order
• Wearing personal protective equipment like masks to avoid inhaling dust

Despite these preventive measures, exposure cannot be completely eliminated, so if you have asthma, be sure to monitor and report any increase in symptoms. One great way to do this is by keeping a ‘symptom diary’ so you can see patterns and determine when symptoms are worse and when they improve. Lastly, always have your Asthma Action Plan and quick-relief (rescue) medicine on hand in case of an emergency. Be sure to follow your Asthma Action Plan, alert your employer and healthcare provider if you are experiencing a flare-up.

By understanding the driving factors of baker’s lung, recognizing early symptoms and taking proactive steps to limit exposure, bakers can continue working safely in the profession they love while also protecting their lung health. Learn more about occupational lung diseases on lung.org.