Adeeb Omer Jafir, Hallo Mahmud Abdullah, Ahmed Ismeal Samad, Ali Hassan Ahmed
The results indicate relatively low radiological exposure from the investigated well water based on the measured radon concentrations and estimated effective doses.
The radon activity concentrations in 25 drinking well water samples and the physicochemical parameter of water quality have been assessed. Samples were collected from 25 different communities in Erbil region, Iraq in April 2026. Measurements were conducted using a RAD7-H2O detector. The measured radon concentrations ranged from 0.151 ± 0.030 Bq/L (W22) to 10.693 ± 1.772 Bq/L (W5), with an average concentration of 3.75 ± 0.594 Bq/L. All measured radon concentrations were below the USEPA critical value of 11.1 Bq/L for drinking water. The calculated annual effective doses due to ingestion for adults, children, and infants ranged from 0.264 to 18.713 μSv/y, 0.311 to 22.081 μSv/y, and 0.520 to 36.891 μSv/y, respectively. On the other hand, the inhalation doses for all ages range from 0.379 to 26.946 μSv/y. Infants exhibited the highest total doses (from both ingestion and inhalation) due to their greater radiation sensitivity and a higher intake-to-body-mass ratio. The measured physicochemical parameters show that all values fall within the acceptable range, except for seven villages where the levels of TDS and EC exceed the established limits. Several samples also show ELCRt values above the commonly used 1x10-4 set by the USEPA's upper-bound risk level in environmental risk assessment. Statistical analysis indicates that there is no significant correlation between radon concentrations and physicochemical parameters due to radon being an inert gas. The results indicate relatively low radiological exposure from the investigated well water based on the measured radon concentrations and estimated effective doses. However, the ELCR assessment identified some well water samples requiring continued monitoring and further assessment, particularly with regard to long-term consumption by infants and children. This study also provides baseline data for future investigations and ongoing monitoring programs in the Kurdistan region of Iraq.