Occurrence and geochemistry of radium in water from principal drinking-water aquifer systems of the United States

Potential Health Risks from Uranium in Home Well Water: An Investigation by the Apsaalooke (Crow) Tribal Research Group

“…These results agree with an analysis of nationwide data, which found a correlation between uranium and oxic waters with a pH in the range of 6.5 to 8.5 as well as high carbonate levels. In these conditions, high uranium also corresponded with high TDS levels [68]. These correlations can be explained: in oxic conditions in shallow groundwater and surface water, uranium most commonly exists as U(VI) in the uranyl ion (UO2 2+ ); this ion typically complexes with the ligand carbonate (or phosphate), which greatly increases the solubility of uranium in water [69].…”

“…Elevated levels of uranium progeny such as radium and radon (along with uranium) have been found to occur in groundwater where there is uranium mineralization [76]. Higher concentrations of radium have been found to be associated with manganese or iron-rich anoxic groundwater [68]. Wells in both the Bighorn and Little Bighorn River valleys are relatively high in manganese, with average concentrations well exceeding EPA's secondary standard of 0.05 mg/L [67].…”

Factors controlling 226Ra, 228Ra and their activity ratio in groundwater – an application in Polish Carpathian mineral waters

“…Some researchers observed the important role of chloride ions in radium desorption from the aquifer rocks into the groundwater, where the 226 Ra content in waters increases with salinity (Martin & Akber 1999, Labidi et al 2010, Roba et al 2012, Vinson et al 2013). The radium concentrations in groundwater are also controlled by the presence of barium and sulfate ions (Sturchio et al 1993, Grundl & Cape 2006, Szabo et al 2012). Reynold and co-workers (2003) reported that in Ojo Alamo (northwest New Mexico) aquifer rocks the 238 U and 232 Th average concentrations amounted to around 40 Bq/kg and 31 Bq/kg respectively, and in the groundwater with a majority of SO 4 2− (from 130 mg/L to 883 mg/L) and a minority of Cl − (from 5.2 mg/L to 70.7 mg/L), the 226 Ra and 228 Ra activity concentrations ranged from tenths of milibekerels per liter to nearly 10 mBq/L respectively, and their activity ratio ( 226 Ra/ 228 Ra) ranged from 0.2 to 0.6.…”

Influence of natural radium contamination of barium chloride on the determination of radium isotopes in the water samples using α/β liquid scintillation spectrometry

“…The amounts 8, 10, 12, 14, 16, and 18 mL of the solution of 0.10 M BaCl 2 ·H 2 O were added to the samples 1, 2, 3, 4, 5, and 6, respectively. Next, the obtained precipitates were purifi ed by dissolving them in ethylenediaminetetraacetic acid (EDTA) 0.25 M, and then, radium was again precipitated following the procedures described by several analysts [14,17,18,21]. The time of the last precipitation for each sample was recorded.…”

“…The probability of bone cancer resulting from the daily consumption of two liters water containing only 18.5 mBq/L of 226 Ra through 70 years amounts to 4 × 10 −5 [11]. The contribution of radium isotopes to the annual committed effective dose resulting from drinking water consumption is around 50% [12][13][14][15][16][17][18]. According to Infl uence of natural radium contamination of barium chloride on the determination of radium isotopes in the water samples using α/β liquid scintillation spectrometry the WHO recommendations, the annual committed effective dose resulting from the intake of natural radionuclides in drinking water and food materials should be lower than 0.1 mSv [19].…”