Faculty of Science – University of Kufa Official Site – Faculty of Science
Nabeel A. Kadhima
, Abdullah S.i Mdekilb
, Hawraa H. abbasc
and Ali A.
Abojassimd*
aMinistry of Education, Najaf Education Office, Najaf, Iraq
bMinistry of Education, General Directorate for Wasit Education, Wasit, Iraq
cPhysics Department, Collage of Science, Baghdad University, Baghdad, Iraq
dPhysics Department, Faculty of Science, University of Kufa, Najaf, Iraq
Abstract
Radon is occurring naturally, odourless, colourless, radioactive, tasteless, and a noble gas. It is the second most important
cause of lung cancer after smoking in many countries. The rate of lung cancers attributable to radon is estimated to range from
3 to 14%. The dose exposure relation is linear, i.e. the risk of lung cancer increases proportionally with increasing radon
exposure. So, it is necessary to measure radon concentrations in the drinking water that is of direct contact with human life
and health. The study included measurement of radon (222Rn) concentrations in some selected samples of drinking water
(bottled water) are available in the Iraqi market. 222Rn concentrations have been measured the usage of alpha spectroscopy
(RAD-7). The RAD-7 measuring process is based on detecting alpha particles produced from the disintegration of radon and
its products using a solid-state alpha detector (usually silicon), and then converting alpha radiation directly to an electrical
signal. The annual effective dose and lifetime cancer risk in six age groups (3 months, 1 year, 5 years, 10 years, 15 years and
adult) associated with the exposure due to an annual intake of 222Rn were calculated. Results show that the average value of
radon concentrations in drinking water samples was ranged from 28.4±2.7 mBq/L to 283±0.34 mBq/L. Also, it is found the
average value of annual effective dose in unit μSv/y for six age groups were 0.48±0.08, 0.62±0.11, 0.18±0.03, 0.22±0.04,
0.37±0.06, and 0.27±0.05,respectively. The average value of lifetime cancer risk in same age groups were (17.99±3.26,
31.13±5.65, 46±8.37, 107.33±19.41, 276.5±50, and 926.33±168)×10-9 respectively. The results of 222Rn concentrations in
present study were found lower than the data of the recommended reference WHO 2008 (500 mBq/L or Bq/m3). Also, the
results showed that the annual effective dose from drinking water exhaustion in six age groups were found lower than the
permitted limit of (1mSv) suggested by UNSCEAR 2000. As well as, values of lifetime cancer risk were within the accepted
level (10-3). Therefore, there are no indications of significant threat from radon concentrations in bottled water brands, and it
is safe as far as a health risk is concerned.
Keywords: Radon concentrations, annual effective dose, excess cancer risk, drinking water and Iraq.
