Association between Local External Gamma Rays and Frequency of Cancer in Babol-Iran

Abstract

Introduction The effect of natural background radiation on Cancer is still challenging. The investigation of association between external gamma rays and Cancer was the main goal of study. Materials & Methods External Gamma rays were measured using a radiation survey meter in 184 urban and rural health centers to estimate the exposure to the population in residential areas of Babol. The dose distribution map was compared to the 5 years radiation induced cancer incidence data from cancer registry center in north part of Iran. Results Results showed that although the external gamma ray level in Babol is nearly equal to the average natural background radiation in the world, there is a relatively weak inverse association between local external gamma ray and incidence of Cancer [Correlation coefficient = −0.43, (p<0.01)]. Conclusion This finding might be due to the inhibition of cancer induction following exposure to the low doses of ionizing radiation and probably can be a confirmation of radiation hormesis. However, due to some uncertainties, the conclusion should be interpreted with caution. Further national and international studies are suggested.