are commonly known as triggers. At least 240 substances are
known to cause OA when inhaled. They are classified in 5
smoke, sulfur dioxide, chlorine gas, ammonia.
Grain flour and
Like Grain dust and flours (like wheat & rye), proteins of
cereal grains, sea food, egg processing, green coffee beans,
castor beans, ispaghula.
allergens & proteins:
These are found in hairs, furs,
dander, scales, saliva and other body wastes like excreta.
are used in pharmaceuticals, detergents, flour conditioners,
1.Acid anhydrides, isocyanides, complex platinum salts, poly
2.Reactive dyes, units manufacturing paints, varnishes,
3.Laminates, soldering fluxes, resins used in soldering.
risk for occupational asthma:
Most of the
triggers are found widely in almost all industries and work
places. But not every one will develop asthma after exposure to
them. Some people are more susceptible to asthma than others. OA
is more common in susceptible individual working in following
Baking and food processing
Working with animals
The development of
occupational asthma depends on:
1. Family history of asthma & allergy
2. Amount of allergen exposure
3. Frequency of exposure to the trigger
4. Cigarette smoking (smoking doubles the chances of having
smoking doubles the risk of
occupational asthma, possibly by recruiting the inflammatory
cells into the lungs where they are available to react with the
irritants and sensitizers.
over several months causes steady deteoration of lung functions.
Clinical features then become indistinguishable from chronic
obstructive lung disease. Common irritants like cold air,
smoking can precipitate asthma attack.
Last edited 22-08-2010
Substances causing Occupational asthma