The principal forms of radiation dosage for humans from spontaneous radiation material are being recognized as radon and its progenitors in the interior environment. Radiation-related health risks are caused by radon in water supply, which can be inhaled or ingested. Materials and Methods: The solid-state CR-39 nuclear trace detectors method was using in this research for measuring accumulation of radioactivity in water supply in different locations of Iraq's southwest corner of Baghdad. In Baghdad district, 42 samples were selected from 14 regions (3 samples out of each region) and put in dosimeters for 50 days. Results: The mean radon concentration was 49.75 Bq/m3, that is lower than the internationally recognized limit of 1100 Bq /m3. The total absorbed dose in micro sieverts each year (mSv/y) and concentration about alpha energy has be estimated. Within the area under study, the linear relation between annual effective dose in (mSv/y) and radon concentration has been established. Conclusion: According on the, findings radon concentrations in drinking water supplies are below than EPA's and WHO's recommended levels.
