Asthma is a common lung condition which causes breathing difficulties.
The main symptoms are wheezing, breathlessness, tightness around the chest and coughing.
Many people first develop asthma when they are children, but it is possible to also develop it as an adult.
According to Asthma UK, one in 10 cases of asthma in adults is caused by work-related factors.
It is the most common cause of adult-onset asthma and makes up 9-15 per cent of cases of asthma in adults of working age.
In some industries, up to 10 per cent of employees develop occupational asthma.
There are two types of occupational asthma: allergic occupational asthma and irritant-induced occupational asthma.
Allergic occupational asthma is the most common type of occupational asthma, and can be triggered by allergens in the workplace, such as flour dust, animal fur, or car fumes.
Allergens that cause occupational asthma are called ‘respiratory sensitisers’ because they can cause changes in your airways, making them hypersensitive.
“It takes a while for your immune system to become sensitive to an allergen, so you may have been able to do your work for weeks, months or even years before you start having asthma symptoms,” said Asthma UK.
“But once you’ve become sensitive to an allergen, it can trigger asthma symptoms the next time you come in contact with it – even if it’s just a small amount of the substance.”
Chemicals commonly found in vehicle spray paint, known as isocyanates, followed by additives used in bakeries, called amylase, are the most common substances causing allergic occupational asthma in the UK.
Jobs with the highest rates of allergic occupational asthma are: vehicle spray painting; baking; woodworking; soldering; healthcare work; working with animals; working in agriculture; engineering; and hairdressing.
“The most important thing to remember is that the reason you developed an allergy to something at work is because you were exposed to large amounts of the allergen for a long time which made you become sensitive to it,” said Asthma UK.
On the other hand, irritant-induced occupational asthma is a non-allergic type of asthma.
It happens when you breathe in a chemical at your workplace, and irritates your airways, causing asthma symptoms.
Irritant-induced asthma isn’t very common and usually happens when there is an accidental chemical spillage in the workplace.
Examples of irritant chemicals include chlorine – used in swimming pools – and ammonia – which is a common cooling agent in refrigerators.
“If there is a chemical spillage at your workplace and you start to experience wheezing, coughing, breathlessness or chest tightness within 24 hours of the spillage, speak to your GP as soon as possible,” said Asthma UK.
“Having allergic occupational asthma doesn’t make you unfit to work. You should talk to your employer (and if you have one, your occupational health doctor or nurse) to see if changes can be made to your current job to make it safer for you, or if you can be given another role.”