Interesting risks here:
Risk to workers depends considerably on their work tasks. For example, machinists in both ceramics and nuclear weapons manufacture have been found to have an increased risk of developing sensitization. This is probably due to small respirable particles of beryllium (<10 microns) that may be better able to deposit deep in the lungs. Other studies have shown that laboratory workers and construction workers in beryllium-using facilities are also at increased risk. However, numerous individuals with apparently trivial exposure, such as security guards, secretaries, and bystanders, have also developed disease. This suggests that a linear dose response may be absent. Inhaling metallic beryllium, beryllium oxide, beryllium-copper and other alloys, or beryllium salts are the major exposure risks leading to disease (Martyny et al. 2000; Sawyer et al. 2002; Willis and Florig 2002)."
I will make sure my beryllium speaker drivers stay intact! (But my nagging cough gets me thinking......)