This practice was passed on to the radium painting industry that also needed fine work. The majority of dialpainting was for wristwatches. The watch at the right was made in the late 1920's by Illinois Watch, Springfield, Illinois. The painting is done exceptionally well. By the 1920's and 1930's some dialpainters and former dialpainters began to suffer from a variety of illnesses, often crippling and frequently fatal as a result of ingesting the radium paint.
Ingested radium is known to deposit permanently in bone structures.
Radiation can then damage bone marrow, causing anemia. It can also weaken the bones so they might crush or snap under normal pressure. It can weaken bone tissue making it easy to get infection such as the jawbones that have dental work or gum disease. It can cause other forms of cancer in the sinus and mastoids. The dialpainters were some of the first victims of radioactive poisoning.