What Is Occupational Asthma ?

Occupational asthma is an illness created in the workplace by a particular material. It is distinguished from preexisting asthma that worsens at work from adverse conditions. Some types of occupational asthma appear to occur more often in allergic individuals, but it is clear that this disease may also occur in nonallergic workers.

The offending agents that produce occupational asthma may occur in many forms, including animal and vegetable proteins, dyes, chemicals, particulates, propellants, and enzymes. These agents can produce reactions in forms such as dusts, vapors, powders, or by direct contact.

Examples of Occupational Asthma

Workers exposed to animals, such as farmers or veterinarians, may develop asthma as a result of sensitization to proteins in animal hair, dander, and urine. Bakers may develop asthma as a result of reactions to flour. Wood-workers may become sensitized to dusts from various woods and develop asthmatic reactions. Workers such as butchers who handle plastic wraps may become sensitized to the material. In the plastics and paint industries a substance known as toluene diisocyanate (TDI) has been shown to be particularly sensitizing. Beauticians may develop asthma as a reaction to chemicals and sprays used in their work. Even these few examples of occupational asthma demonstrate how significant this problem may be for workers

and industry.

Latex Allergy: On the Rise

A striking and often severe example of occupational asthma occurs from exposure to latex. Allergy to latex has increased dramatically in the last two decades. This increase is directly related to the AIDS epidemic of the 1980s which prompted a tremendous increase in the use oflatex gloves. It is estimated that since 1980, the number of people in the general population with latex allergy has increased to 8 percent from 1 percent. Among dental workers, the number with latex sensitivity has increased to 40 percent from 7 percent, while other health care workers have experienced an increase to 20 percent from 3 percent.

In order to produce allergy, latex proteins must enter the body. The most common source is the powdered cornstarch used in latex gloves. The latex protein combines with this powder during manufacturing. Patients breathe in this dust when the gloves are slipped on. Latex protein may also enter the body through direct contact so that allergic reactions may occur during or after surgery or procedures.

Latex-induced asthma is often severe, requiring health care workers to leave their occupations. Many health care centers have taken steps to reduce latex exposure through the use of nonlatex, powderless gloves. Latex gloves, however, are still used in most surgeries since they provide the best protection against infection. Allergy testing for latex is widely available so anyone who suspects the presence of this allergy should be tested.

When Should I Suspect Way Have Occupational Asthma?

The basis for such a diagnosis comes from a thorough occupational history linked to physical and laboratory findings under the direction of a physician. But the patient is the one who calls medical symptoms to the attention of the physician. A high degree of awareness helps identify what may be occupational sources of asthma.