Assessment of concentration of radon 222 and effective dose; Bandar Abbas city (Iran) citizens exposed through drinking tap water

Radon 222 is a natural radioactive element with 3.825 days half-life. 222Rnis colorless and odorless with highsolubility in water. The presence of 222Rnin drinking water can lead to lung or stomach cancers through chronicexposure per inhalation or ingestion. Different age groups have different sensitivity to the health effects of 222Radon.In this cross-sectional study, the concentration of 222Rnin the 8 regions of Bandar Abbas city in 48 samples of tapwater was measured by portable Radon meter RTM1688-2 model on June 2015. The effective dose by tap water wasalso calculated in different age groups through UNSCEAR equation. The range and mean concentration of 222Rnis0.87-0.384 Bq/l and 0.232±0.7 Bq/l, respectively. The mean of the effective dose of exposure for the age groups was0.0024±0.0007, 0.0018±0.0005, 0.0007±0.0002 and 0.001±0.0003 m Sv/y, respectively for adult males, adultfemales, children and infants. The magnitude’s order of measured doses of studied age groups was: adult males>adultfemales>infants>children. The effective doses, ingested by all groups, are less than the standard limits particularly for children (p value<0.001).The results of this research shows that222Rn concentration in the tap water of Bandar Abbascity is lower than WHO, EU and EPA standard limits (p value<0.001). Also the effective 222Rn doses in the all agegroups are much lower than standard limits. Given the daily high consumption of water, adult males between the Bandar Abbas citizens showed the highest sensitivity to the 222Rn health hazard.