Abstract:The difference in the concentration of dissolved radon ( 222 Rn) in drinking water from wells and streams around Lumwana area in Zambia remains of interest because of the radiation-induced public health hazards. A total of nine (09) communities around Lumwana mine were selected for this study because their sources of drinking water are wells and streams. The underlying geology of this area is predominantly high grade, metamorphosed, intensely mylonitised, recrystallised muscovite-phlogopite-quartz-kyanite schists with disseminated sulphides (typically < 5%), dominated by chalcopyrite and bornite with known elevated concentrations of uranium, which ultimately decays to radon gas. The main aim of this paper is to estimate the contribution of ( 222 Rn) to public exposure due to natural radioactivity in drinking water. The concentration of radon levels in the collected water samples was analyzed using an Alpha Spectrometer called RTM (radon thoron monitor 2200) and the average results were found to vary from 4.44 Bq/L to 32.13 Bq/L. The obtained values are lower than the WHO (world health organization) recommended guidelines for drinking-water quality value of 100 Bq/L. The annual effective dose for the adults in these communities were in the range of 16.21 to 117.28 µSv/a slightly above the WHO recommended guideline reference dose level of 100 µSv/a.