Abstract
Among the lofty mountains of Karakoram ranges in Northern Pakistan, lies the Hunza Valley, home of a community of disease and cancer free people said to survive longer with life expectancy of around 100 years, whereas the average life expectancy in Pakistan is 67 years. Indoor radon measurements were carried out in the five villages of Hunza-Valley. The average Radon concentration levels were found to be 52.97 +/- 25.25, 43.49 +/- 16.04, 34.15 +/- 17.93, 30.38 +/- 10.82 and 30.80 +/- 19.48 Bqm(-3)respectively in Hassianabad, Altit, Murtazabad, Karimabad and Aliabad. The annual effective dose was calculated as 0.68 +/- 0.32, 0.5 +/- 0.20, 0.44 +/- 0.23, 0.4 +/- 0.14 and 0.25 +/- 0.06 mSvy(-1)in the above mentioned five villages. The radon concentration levels, are much below the action level recommended by the ICRP (300 Bqm(-3)), USEPA (150 Bqm(-3)), and WHO (300 Bqm(-3)). Radiation hormesis that the low doses of ionizing radiation are beneficial, stimulating the activation of repair mechanisms that protect against diseases, is the possible reason for their long life and absence of diseases and cancer from the region.