In the year following Röntgen`s discovery of X-rays in 1895, approximately 60 cases of hand dermatitis and hair loss induced by radiation were reported. People using X-rays in their occupation, including X-ray tube manufacturers, physicians, and engineers, experienced chronic radiation dermatitis and were the first to be diagnosed with occupational radiation exposure. Reports of later appearing disorders, including skin cancer, suffered by doctors and engineers, were regarded as serious occupational diseases. In the 1910's, blood disorders, including leukemia, in people with occupational exposure to radiation came into focus. Dial painters applying radium to watches with a luminous dial clock face suffered osteomyelitis from about 1914. Other radiation damage reports include radiation death and carcinogenesis in the Chernobyl nuclear power plant accident in 1986, and radiation death in the Tokai-mura JCO accident in 1999. The details of radiation damage in the Fukushima Daiichi Nuclear Power Plant in 2011 have not yet been reported, but must be followed in the future.