Isolating asthma

Asthma most often arises during childhood, but adults exposed regularly to certain industrial chemicals are also at risk for developing the disease. Figuring out why children get asthma can be enormously complex, but the cause of the disease when it develops in the workplace can sometimes be identified. Yale researchers hope that studying work-related asthma may lead to new ways of preventing it from developing in exposed workers, as well as to a better understanding of the mechanisms underlying other types of asthma.

Certain adults develop asthma due to workplace exposure to specific chemicals. These can include doctors, dentists and nurses, who are exposed to latex in gloves, and beauty salon workers, who are exposed to hair sprays and nail polishes. One of the most common causes of workplace asthma is exposure to isocyanates. These chemicals are found in the hard, shiny spray paints and lacquers used in auto-body shops and in numerous polyurethane foam and plastic products such as mattresses and boat hulls. Somewhere between 5 and 20 percent of workers who are exposed to isocyanates develop asthma. “It’s a problem in industry,” says Carrie Redlich, M.D., who is directing studies of work-related asthma. “Once you get asthma you need to get away from the chemicals. You can lose your livelihood.”

Working with small auto-body shops around New Haven, Dr. Redlich, an associate professor of medicine, has been investigating the allergy process, as well as who is in danger of getting the disease and, when they do get asthma, what actually happens in the lungs. Dr. Redlich gives asthmatic workers controlled doses of isocyanates in an exposure chamber—the only one of its kind in the U.S.—and then studies the physiologic and immunologic responses. She can also expose human lung cells to isocyanates to better understand how the chemicals cause asthma.

Eventually she hopes to develop a test to see who among industrial workers have begun to develop the disease. “If we can identify them early enough,” Dr. Redlich says, “and get them away from exposure, we may be able to prevent the development of asthma. But if you miss them, they may go on to develop chronic asthma that could be with them—and possibly disable them—for the rest of their lives.”