CHICAGO — The U.S. Occupational Safety and Health Administration, long criticized for downplaying the dangers of beryllium, has discovered several of its employees have been affected by exposure to the deadly metal.

According to the Chicago Tribune, testing has shown at least three OSHA workers developed blood abnormalities linked to beryllium exposure – the first such cases at the agency. The workers are believed to have been exposed while conducting safety inspections in industries using beryllium, a lightweight metal whose dust can cause an often-fatal lung disease.

Beryllium is used in a variety of industries to help make products ranging from missile components to laptop computers to golf clubs. The safety agency estimates that 1,000 inspectors, or three-fourths of its force, have conducted inspections in industries handling the metal.

People who have blood abnormalities do not necessarily have beryllium disease; the abnormalities mean the body’s immune system has reacted to beryllium exposure. Further tests, such as a lung biopsy, are needed to confirm illness. Experts estimate about half the people with blood abnormalities will develop the disease.

OSHA officials said until testing is complete, they would not comment on results nor confirm whether any employees have blood abnormalities. But sources said that at least three do.

Details of the cases, including who was affected and where they worked, were unavailable. But OSHA records obtained by the Tribune show agency employees have conducted inspections in numerous facilities nationwide with high levels of beryllium dust.