Abstract
Available data on cancer mortality in the employee populations of the five units of the Department of Atomic Energy (DAE) were analysed. The population groups consisted of employees from research reactors, power reactors, nuclear fuel fabrication facility and thorium processing industry. The group includes all the employees of these facilities, i.e. both radiation workers and others not directly associated with radiation work. Data available only in the serving employees, i.e. subjects in the age group 20-59 yrs and not on the retired employees are analysed. A total of 81 cancer deaths recorded in a database of 315519 Person-Years were analysed. Among these, 28 deaths were recorded among monitored radiation workers having a database 112363 Person-Years. Using background age-specific cancer death rates of the urban Indian populations as a tentative national baseline, the estimated Standardised Mortality Ratio (SMR) for combined DAE employees works out to be 111 (95% CI: 80-138). The SMR for radiation worker alone is 108 ((95% CI:72-156) as compared with the SMR of 113 (95% CI:84-149) for non-radiation workers. The relative risk of Radiation workers as compared to Non-radiation workers is 0.96(95% 0.64-1.39). The study shows that the radiation workers are not at any extra risk of cancer as compared to non-radiation workers. Also, when considered as a whole, comparison with the national baseline data does not indicate any extra cancer risk for atomic energy employees of India.
