Measurement uncertainty estimation of health risk from exposure to natural radionuclides in soil

Cancer mortality risk were estimated due to external exposure to 40K in soil. Uncertainty estimation was performed for the risk considered as a measurand. It was presented uncertainty estimation using two methods. One method is based on the Guide to the Expression of Uncertainty in Measurement Framework (GUF) and other represents Monte Carlo method. For the Monte Carlo method, the mean of the obtained distribution that represents mortality cancer risk estimation, due to one year exposure to 40K with mean activity concentration of 708 Bq/kg in soil, is 12.9 × 10−6 with 90% confidential interval (k ≈ 1.64) of (4.7-25.5) × 10−6. According to GUF the mean value is estimated as 10.9 × 10−6, with 90% confidential interval of (0.9-20.8) × 10−6. Uncertainty of assessed risk obtained by numerical simulation is slightly different with asymmetrical boundaries related to the mean value, comparing to the uncertainty estimated using GUF.