U.S. Radium Corporation hired approximately 70 women to perform various tasks including handling radium, while the owners and the scientists familiar with the effects of radium carefully avoided any exposure to it themselves; chemists at the plant used lead screens, aprons, masks and tongs. U.S. Radium had distributed literature to the medical community describing the "injurious effects" of radium. In spite of this knowledge, a number of similar deaths had occurred by 1925, including the company's chief chemist, Dr. Edwin E. Leman, and several female workers. The similar circumstances of their deaths prompted investigations to be undertaken by Dr. Harrison Martland, County Physician of Newark.