USGS-NWQL: I-4403: Lead, whole water recoverable, GFAA
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Official Method Name
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Lead, atomic absorption spectrophotometry, graphite furnace |
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Current Revision
| 1989 |
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Media
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WATER |
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Instrumentation
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Graphite Furnace-Atomic Absorption Spectrometer |
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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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Methods for the Determination of Inorganic Substances in Water and Fluvial Sediments, Techniques of Water-Resources Investigations of the United States Geological Survey, Book 5, Chapter A1 Edited by Marvin J. Fishman and Linda C. Friedman |
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Brief Method Summary
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Lead is determined by atomic absorption spectrophotometry in conjunction with a graphite furnace containing a graphite platform (Hinderberger and others, 1981). A sample is placed on the graphite platform, and a matrix modifier is added. The sample then is evaporated to dryness, charred, and atomized using high-temperature ramping. The absorption signal produced during atomization is recorded and compared with standards. |
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Scope and Application
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This method is used to determine lead in samples of water-suspended sediment with a specific conductance not greater than 10,000 uS/cm. With Zeeman background correction and a 20-uL sample, the method is applicable in the range from 1 to 25 ug/L. Sample solutions that contain lead concentrations greater than 25 ug/L must be diluted or be analyzed by an alternate method. Whole water recoverable lead in samples of water-suspended sediment must undergo preliminary digestion by method I-3485 before being determined. |
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Applicable Concentration Range
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1 - 25 ug/L |
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Interferences
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Interferences for samples with specific conductances less than 10,000 uS/cm normally are small. In addition, the use of the graphite platform reduces the effects of many interferences. Special precautionary measures to prevent contamination need to be used during sample collection and laboratory determination. |
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Quality Control Requirements
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Calibrate instrument using calibration standards (CAL). Quality control samples (QCS) and laboratory blanks (LB) analyzed at a minimum of I each after every 10 samples |
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Sample Handling
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Container Description: 250 mL Polyethylene bottle, acid-rinsed. Treatment and Preservation: Use unfiltered sample to rinse bottles, then acidify collected sample with HNO3 to pH < 2. |
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Maximum Holding Time
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180 days |
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Relative Cost
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$51 to $200 |
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Sample Preparation Methods
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I-3485 |
