Notes on the Toxicology of Cobalt Metal

This investigation originated in a report by Dr. Joan Cotterill, one of H.M. medical inspectors of factories, that workers in a Midlands factory making hard cutting tools complained of shortness of breath and that in radiographs of their lungs, some of them showed abnormal shadows. Many of the processes in the factory are trade secrets, but it is known that powdered cobalt metal is used as a bonding material in the manufacture of hard cutting tools containing tungsten carbide and other substances.