USGS-NWQL: I-1472-85: Metals, dissolved, water, ICP-AES (Archive method)
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Official Method Name
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Dissolved Metals in Water by Atomic Emission Spectrometry Using Induction-Coupled Plasma (ICP) |
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Current Revision
| 1985 |
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Media
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WATER |
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Instrumentation
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Inductively Coupled Plasma - Atomic Emission Spectroscopy |
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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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All parameters are determined simultaneously on a single sample by a direct-reading emission spectrometric method utilizing an induction-coupled argon plasma as an excitation source. Samples are pumped into a pneumatic nebulizer, atomized, and introduced into the plasma via a spray chamber and torch assembly. Each analysis is determined on the basis of the average of two replicate exposures, each of which is background-corrected by a spectrum-shifting technique. Calibration is performed by standardizing with a series of four mixed-element standards and a blank. |
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Scope and Application
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This method may be used only for the determination of dissolved constituents in water that have a measured specific conductance of less than 2,000 S/cm at 25oC. Samples containing analyte concentrations greater than the upper concentration limit may be analyzed for calcium, magnesium, silica, and sodium if the sample is diluted and if, after dilution, the specific conductance is below 2,000 S/cm. Trace metals can also be determined in samples that have a measured specific conductance greater than 2,000 S/cm by dilution; however, detection levels and sensitivity will change proportionally. |
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Applicable Concentration Range
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0.0005 - 1000 mg/L. Ranges differ for each analyte. This range is taken from the lowest and highest limit of the analytes listed in the method. |
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Interferences
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I. SPECTRAL INTERFERENCES: (1) Background emission or stray light. (2) Spectral overlap of emissions. II. PHYSICAL INTERFERENCES: High viscosity or high particulate levels of sample can clog nebulizer. III. CHEMICAL INTERFERENCES: (1) Compound formation. (2) Ionization. (3) Solute-vaporization. IV. MEMORY INTERFERENCES: Carry-over from sample. |
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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. (Reference OFR 95-443). |
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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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Relative Cost
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$201 to $400 |
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Sample Preparation Methods
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