Measurement of natural ambient gamma radiation levels and estimation of population dose in tobacco-growing places of Karnataka state

Abstract

Abstract Karnataka state is the fourth largest tobacco-growing state in India and Mysore district has large tobacco cultivation. The fertilizers contain the primary nutrients NPK (Nitrogen, Phosphorus and Potassium). This is also responsible for enhancing the gamma radiation level in rural areas of cultivated land of tobacco growing places, in addition to the natural gamma radiation. The aim and objectives of the present study consist of the measurement of the natural ambient gamma radiation dose level, and dose to the public. The natural ambient gamma radiation levels in some tobacco growing places of the Karnataka state were measured by a scintillation survey meter. The ambient gamma absorbed dose rate in cultivated and non-cultivated land varies from 34.8±0.3 nGyh-1 to 226.2±5 nGyh-1, with a mean value of 84.77±1.9 nGyh-1, and 26.1±0.3 nGyh-1 to 182.7±4 nGyh-1, with a mean value 58.82±1.2 nGyh-1 respectively. The indoor and outdoor gamma absorbed dose rate of the villages of the study area varies from 52.2±0.4 nGyh-1 to 234.9±4.5 nGyh-1, with a mean value of 100.89±2.3 nGyh-1, and 30.45±0.5 nGyh-1 to 165.3±3.5 nGyh-1, with a mean value of 63.19±1.3 nGyh-1 respectively. The annual effective equivalent dose rate of the study area varies from 0.293mSvy-1 to 1.344mSvy-1, with a mean value of 0.572mSvy-1. The indoor, tobacco leaves stored houses and the cultivated land shows higher gamma radiation dose rates than the outdoor atmosphere of the villages and non-cultivated land. The present study was able to establish a baseline data of Annual Effective Dose (AED) and assess gamma radiation dose rate of the study area. The results were presented and analyzed systematically from the radiation protection point of view.