Occupational Asthma

Occupational Asthma

What is Occupational Asthma?

Occupational asthma (OA) is a type of asthma that occurs due to inhalation of various types of irritants, chemical fumes, dust, and other toxic substances at the workplace. The type of toxic insult varies with the occupation. People susceptible to allergies are more prone to suffer from OA. Management essentially involves avoiding the incriminating agent. Medical treatment is the same as for general asthma.

Types of Occupational Asthma

OA can be categorized into two types – immunological and non-immunological:

  • Immunological OA: This type of OA occurs due to an immunological reaction and is mediated by a type of antibody called immunoglobulin E (IgE). Immunological OA exhibits a latency period. It can be caused by both high molecular weight (HMW) and low molecular weight (LMW) agents.
  • Non-immunological OA: This occurs due to acute toxic injury by single or multiple agents. It is characterized by a sudden onset, without any latency period and can give rise to a condition called Reactive Airways Dysfunction Syndrome (RADS). It is caused by toxic chemicals and other irritants.

Prevalence of Occupational Asthma

Asthma affects 5-10 percent of people worldwide, of which approximately 2-15 percent is occupational in origin. The prevalence of OA varies with the type of profession, but the data is scanty, which is currently available for only three categories of occupations:

  • Animal lab personnel: 8-12 percent
  • Bakers: 7-9 percent
  • Healthcare personnel: 1.4 percent

High Risk Occupations

The workers having the riskiest occupations and the corresponding agent(s) that they are exposed to are tabulated below:

Occupation Agent
Bakers, millers Wheat flour
Animal handlers, animal lab personnel, veterinarians Dander, fur, hair
Healthcare personnel Natural rubber latex, drugs
Metal workers, welders Chromium, nickel, platinum
Carpenters Wood dust
Hairdressers, barbers Hair dyes
Cooks Milk / egg powder, fish (herring, crab)
Farmers Insecticides, pesticides
Plastic / adhesive / foam / textile industry workers, spray painters Chemicals
Laundry workers Detergents
Window cleaners, road / chimney sweepers Dust, dirt, smoke

Latest Publications and Research on Occupational Asthma