Determination of radiological parameters of igneous rocks of Alvand zone of Hamadan, Iran

Humans are usually exposed to ionizing radiations. Quantity of this radiation depends on kind of rocks, soils and geographical zone. In this research investigated radioactivity and radiological parameters of igneous rocks of Alvand zone in Hamadan in 400 hectares area. Annual Gonadal Dose Equivalent (AGDE) for samples varied from 126. 11 ± 3. 45 to 1984. 25 ± 28. 43 with average 639. 90 in µSv/y that is more than world average (416. 35). Excess Lifetime Cancer Risk (ELCR) for samples calculated which are in range (1. 27-0. 07) ×10-3 with average of 0. 41× 10-3. For all samples except sample with PGG (W) code are less than maximum acceptable value. Mean of ELCR for samples is more than world average. The I7 value for studied samples in this research varied from 0. 27 to 4. 53 with mean 1. 45 which for most samples are more than unity. For safety the region, this quantity should be less than one. The results of this study show that the amount of gamma rays is not safe for population.