ASTM: D5673: Elements in Water by ICP-MS
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Official Method Name
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Standard Test Method for Elements in Water by Inductively Coupled Plasma-Mass Spectrometry |
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Current Revision
| 1996 |
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Media
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WATER |
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Instrumentation
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Inductively Coupled Plasma - Mass Spectrometry |
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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 test method describes the multi-element determination of trace elements by inductively coupled plasma - mass spectrometry (ICP-MS). Sample material in solution is introduced by pneumatic nebulization into a radiofrequency plasma where energy transfer processes cause desolvation, atomization, and ionization. The ions are extracted from the plasma through a differentially pumped vacuum interface and separated on the basis of their mass-to-charge ratio by a quadrupole mass spectrometer. The ions transmitted through the quadrupole are detected by a continuous dynode electron multiplier assembly and the ion information processed by a data handling system. |
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Scope and Application
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This test method covers the determination of dissolved elements in ground water, surface water, and drinking water. It may also be used for the determination of total-recoverable elements in these waters as well as wastewater. This method should be used by analysts experienced in the use of ICP-MS, the interpretation of spectral and matrix interferences and procedures for their correction. . |
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Applicable Concentration Range
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Varies by analyte (ug/L). |
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Interferences
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Several types of interference effects may contribute to inaccuracies in the determination of trace elements. 1)Isobaric elemental interferences are caused by isotopes of different elements which form singly or doubly charged ions of the same nominal mass-to-charge ratio and which cannot be resolved by the mass spectrometer in use. 2)Abundance sensitivity is a property defining the degree to which the wings of a mass peak contribute to adjacent masses. 3)Isobaric polyatomic ion interferences are caused by ions consisting of more than one atom that have the same nominal mass-to-charge ratio as the isotope of interest, and which cannot be resolved by the mass spectrometer in use. 4)Physical interferences are associated with the physical processes that govern the transport of the sample into the plasma, sample conversion processes in the plasma, and the transmission of ions through the plasma-mass spectrometer interface. 5)Memory interferences result when isotopes of elements in a previous sample contribute to the signals measured in a new sample. |
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Quality Control Requirements
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Sample Handling
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Collect the samples in accordance with the applicable standards, Practice D 1066, Specification D 1192, or Practices D 3370. Preserve the samples at the time of collection by immediately adding nitric acid (sp gr 1.42) to adjust the pH to 2. If only dissolved elements are to be determined, filter the sample through a 0.45-um membrane filter before acidification. |
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Maximum Holding Time
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Relative Cost
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$201 to $400 |
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Sample Preparation Methods
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