Radon
concentration values obtained in the water samples in
this investigation generally lay above the range
reported by other investigators except the radon concentration
values reported in outer Himalayas(18) and
in Garhwal Himalayas(19) as given in Table 2.
The estimated total annual effective dose of
adults ranged from 1.34 to 229.68 mSv y–1. The
values of the mean annual effective dose per person
for adults caused by different water samples in this
study are reported in Table 1. The World Health
Organization(11) and EU Council(12) recommended the
safe limit of the annual effective dose received from
drinking water consumption to be 0.1 mSv y–1 from
these three radioisotopes: 222Rn, 3H 40K. So the total
annual effective dose from the three locations of the
studied area is found to be greater than the safe limit.