EPA-NERL: 218.3: Chromium by Chelation Extraction and Flame AA
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Official Method Name
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Chromium (Atomic Absorption, Chelation-Extraction) |
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Current Revision
| Issued 1978 |
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Media
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WATER |
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Instrumentation
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Flame Atomic Absorption |
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Method Subcategory
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Inorganic |
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Method Source
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Citation
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Brief Method Summary
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This method is based on the chelation extraction of hexavalent chromium with ammonium pyrrolidine dithiocarbamate (APDC) following oxidation of trivalent chromium. The chelate is extracted with methyl isobutyl ketone (MIBK) and is analyzed using a flame atomic absorption spectrometer. Specifications for instrument operation and preparation of standards are provided. An alternative extraction is also described in EPA Method 200.0, Section 9.2, which uses pyrrolidine dithiocarbamic acid in chloroform. |
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Scope and Application
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This method determines total chromium in drinking, surface and saline waters, and certain domestic and industrial wastes (provided that no interferences are present). |
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Applicable Concentration Range
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1-25 ug/L. |
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Interferences
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Reactive Metals: High concentrations of other reactive metals, as may be found in wastewaters, may interfere (but not at levels normally found in fresh water). For additional interferences see EPA Method 200.0. |
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Quality Control Requirements
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QC requirements for drinking water procedures are provided in method 200.0 |
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Sample Handling
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Sample handling and preservation procedures are provided in EPA Method 200.0. |
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Maximum Holding Time
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6 months (MCAWW, Table 1). |
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Relative Cost
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Less than $50 |
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Sample Preparation Methods
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200.0 |
