DOE: RP450: Radium-226 in Aqueous Samples
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Official Method Name
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Determination of Radium-226 in Aqueous Samples |
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Current Revision
| 1997 |
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Media
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WATER |
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Instrumentation
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Alpha Spectrometer/Counter |
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Method Subcategory
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Radiochemical |
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Method Source
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Citation
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Brief Method Summary
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A 1 to 50 mL sample is passed through a cation-exchange column to separate radium from other constituents. After preconcentration separation, the radium is electrodeposited on a stainless steel disc from an acidic plating solution in the presence of microgram amounts of platinum. The electrodeposition method is direct, highly sensitive, and highly specific. After electrodeposition, the disc containing the radium is placed in an alpha counter to determine Ra-226. |
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Scope and Application
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This method separates out and determines Ra-226 in groundwater, tap water, drinking water, biological samples, and dissolved soils. If Ra-224 is present in the sample, low levels of this isotope can also be measured. |
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Applicable Concentration Range
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0.0034Bq/mL - 0.34Bq/mL |
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Interferences
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(A) Barium: Barium can result in low yield during electrodeposition, but is removed with a 1.5 HCl wash. (B) Elemental Interferences: U-234 and Th-230 cannot be resolved from spectral peaks of Ra-226. |
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Quality Control Requirements
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Run one blank per sample batch. Run duplicate samples, one spiked with Ra-224, to determine if Ra-224 is present. |
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Sample Handling
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Samples should be acidified to pH < 2 with HCl or HNO3. |
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Maximum Holding Time
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Relative Cost
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$51 to $200 |
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Sample Preparation Methods
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