Some beryllium processes, especially machining, are associated with an increased risk of beryllium sensitization and disease. Little is known about exposure characteristics contributing to risk, such as particle size. This study examined the characteristics of beryllium machining exposures under actual working conditions. Stationary samples, using eight-stage Lovelace Multijet Cascade Impactors, were taken at the process point of operation and at the closest point that the worker would routinely approach. Paired samples were collected at the operator’s breathing zone by using a Marple Personal Cascade Impactor and a 35-mm closed-faced cassette. More than 50% of the beryllium machining particles in the breathing zone were less than 10 μm in aerodynamic diameter. This small particle size may result in beryllium deposition into the deepest portion of the lung and may explain elevated rates of sensitization among beryllium machinists.
From the Division of Environmental and Occupational Health Sciences, National Jewish Medical and Research Center, Denver, Colo. (Dr Martyny, Ms Mroz, Dr Maier, Ms Sheff, Dr Newman); the Lovelace Respiratory Research Institute, Albuquerque, N.M. (Dr Hoover); Colorado State University, Fort Collins, Colo. (Ms Ellis); and the Department of Medicine and Preventive Medicine and Biometrics, University of Colorado Health Sciences Center, Denver, Colo. (Dr Maier, Dr Newman).
Address correspondence to: John W. Martyny, PhD, Division of Environmental and Occupational Health Sciences, National Jewish Medical and Research Center, 1400 Jackson Street, Denver, CO 80206.