Standard Methods: 3120 B (total): Metals (total recoverable) in Water by ICP
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Official Method Name
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Metals in Water by Plasma Emission Spectroscopy |
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Current Revision
| Standard Methods Online |
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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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Brief Method Summary
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For sample preparation, see Standard Method 3030 F. Follow manufacturer's instructions for instrument operation. For each analytical line establish detection limit, precision, optimum background positions, linear dynamic range, and interferences. Verify the reproducibility of the instrument configuration and operating conditions by using an atom-to-ion emission intensity ratio. Warm up the instrument for 30 minutes. Perform an optical alignment for polychromators. Check spectrometer entrance slit and alignment of plasma torch. Follow manufacturer's procedure to calibrate instrument. Aspirate for at least 15 seconds after reaching the plasma before beginning signal integration. To eliminate carryover from the previous standard, rinse for 60 seconds with calibration blank. Analyze instrument check standard before analyzing samples. Analyze samples, alternating with the analysis of a calibration blank. Rinse for 60 seconds with dilute acid between samples and blanks. Let system equilibrate before starting signal integration. Repeat rinsing if carry over is observed. A sample or standard aerosol is generated in an appropriate nebulizer and spray chamber, and is injected into the plasma. The ICP subjects the sample to temperatures of 6000 to 8000 K. The resulting ionization of a high percentage of atoms produces ionic emission spectra. Emission spectra can be analyzed using a monochromator to examine emission wavelengths sequentially, or by using a polychromator, which simultaneously monitors all configured wavelengths using a computer controlled readout system. The sequential approach provides greater wavelength selection while the simultaneous approach can provide greater sample throughput. |
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Scope and Application
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This method allows for determination of metals in water by ICP-AES. |
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Applicable Concentration Range
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DL - 100mg/L. Ranges differ for each analyte. This range is taken from the lowest and highest limit of the analytes listed in the method. [Note: (DL) = Detection Limit] |
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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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QCS, CB (see Standard Methods Section 3020) |
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Sample Handling
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Collect samples in plastic or glass containers that have been rinsed with 1+1 HNO3. Acidify samples to a pH < 2 with HNO3. For dissolved metals, filter samples immediately. Analyze within 6 months. |
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Maximum Holding Time
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6 months |
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Relative Cost
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$201 to $400 |
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Sample Preparation Methods
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