Evaluation of Toyserkan City's Water Contamination, due to The Existence of Radon, and Estimation of The Annual Effective Dose

Abstract

The gas of ²²²Rn is one of the natural radioactivesources which is the decay product of ²²⁶Ra from ²³⁸U decay chain. Based on the latest information presented bythe United Nations Scientific committee in the field of the effects of atomic radiations, the respiration of Radon and its daughters (Plutonium, Bismuth and Lead), are one of the most important factors in human radiation inhalation, since Radon and its daughters account for approximately 1.2 msv of the total of 2.4 msv (mili Sievert) annual effective dose of natural radioactive sources produced. The fluctuation in the levels of Radon resolved in water, due to the hazards caused by the emitted radiations, is considerable; because studies show that long-term exposure to Radon increases the chances of lung cancer. The amount of radon in underground waters is more than that of surface waters. If water is exposed to free air, especially when it’s mixed as well, a considerable amount of its radon content is released. In this paper, Radon concentration (Bq/L) in waters of the wells and springs located in Toyserkan, is measured using Lucas chamber technique by means of a light weighted and transportable machine namely PRASSI (SFLENAmod5s). The results showed that the radon density in four measured samples in the waters of this region exceed 10 Bq/L, the allowable amount determined by the US Environmental Protection Agency (USEPA). For the cases where the concentration is high, is it proposed that drinkable water be preserved in open pools or at least waterfalls be used in order to agitate the water to release itsradon content. It is better to install a system for settling and exposing the water to air so that Radon and its decay products are dispersed and the contamination problem is solved.