Lifetime Cancer Risk Due to Alpha Emitters in Water Samples for Some Marshes in Dhi-Qar Governorate, Iraq

Abstract Background: Radon (222Rn), radium (226Ra), and uranium (238U) concentrations in the samples of marshes’ water have been measured. The samples were collected from various places at the marshes, in Dhi-Qar governorate. Also, the annual effective dose (AED), with lifetime cancer risk due to ingestion of 222Rn and 226Ra in drinking water were calculated. Materials and Methods: Solid State Nuclear Tracks Detectors (SSNTD ) type CR-39 in present study was used. Results: The average values of 222Rn, 226Ra and uranium 238U concentration in water samples were found to be 0.282±0.03 Bq/l, 0.46±0.05 Bq/l, and 0.59±0.08 mg/kg respectively. The average values of AED caused by ingestion of 222Rn and 226Ra in the samples of the study were found to be 0.018±0.002 mSv/y and, 0.091±0.012 mSv/y, respectively. The average values of total AED and lifetime cancer risk values were calculated to be 0.11±0.01 mSv/y and (4.26±0.60)×10-4, respectively. Conclusions: The average concentration values of 222Rn and 226Ra were found to be within the global average limitations (0.4 Bq/l), and (1 Bq/l) that are recommended by World Health Organization (WHO) 1993 and 2011, while the average of 238U concentrations were within the global average limitation (0.566 mg/kg) that was recommended by Environmental Protection Agency "EPA". When some results of AED due to 222Rn and 226Ra concentrations, in the samples under study, were compared with the worldwide median value, that is recommended by WHO 2011; it was found that the lifetime cancer risk in all samples of the present study were higher than the safety limit for the healthy drinking water. Therefore, the water of Marshes that consume in the Dhi-Qar governorate- Iraq, for drinking no healthy.