Standard Methods: 7500-Cs B: Radioactive Cesium by Precipitation
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Official Method Name
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7500-Cs B. Precipitation Method |
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Current Revision
| Standard Methods 21st Edition (2005); Standard Methods Online |
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Media
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WATER |
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Instrumentation
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Not Applicable |
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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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If the activity of cesium is high, radioactive cesium can be determined directly by gamma counting a large liquid sample (4 L) or the sample can be evaporated to dryness and counted. For lower level environmental samples, add cesium carrier to an acidified sample and collect the cesium as phosphomolybdate. This is purified and precipitated as Cs2PtCl6 for counting. If total radiocesium determined by beta counting exceeds 30 pCi/L, determine 134-Cs and 137-Cs by gamma spectrometry. |
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Scope and Application
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Radioactive cesium has been considered one of the more hazardous radioactive nuclides produced in nuclear fission. Upon ingestion, like potassium, cesium distributes itself throughout the soft tissue and has a relatively short residence time in the body. Half lives of 134-Cs and 137-Cs are 2 and 30 years, respectively, both being beta and gamma emitters. |
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Applicable Concentration Range
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Interferences
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Quality Control Requirements
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See Section 7020 Quality Assurance/Quality Control. |
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Sample Handling
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Plastic or glass containers. Preserve samples with concentrated HCl or HNO3 to ph <2. |
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Maximum Holding Time
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1 year |
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Relative Cost
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$51 to $200 |
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Sample Preparation Methods
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