Six-year clinical and immunologic follow-up of workers exposed to trimellitic anhydride.

We report a 6-year study from 1979 through 1985 of workers exposed to trimellitic anhydride (TMA) in three groups of volunteers. Twenty-nine percent of workers (5/17) originally studied had immunologically induced respiratory disease. Subsequent to this evaluation, increased environmental control of TMA exposure was instituted. Since that time, there have been decreasing clinical symptoms and decreasing levels of antibody against TMA conjugated to human serum albumin. These long-term studies originally used radioimmunoassays, but enzyme-linked immunoassays against TMA-conjugated proteins are now demonstrated to be equally appropriate and are more cost-effective. With appropriate clinical and immunologic studies, immunologic airway reactions to TMA may be identified and then prevented by environmental control to decrease inhalation exposure to TMA. This is likely applicable to certain other chemical antigens that immunize by inhalation.