USGS-NWQL: I-6062: Arsenic, total in bottom material, various, hydride _AA
Official Method Name
|
Arsenic, atomic absorption spectrometric, hydride, automated |
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Current Revision
| Revised 1985 |
Media
|
VARIOUS |
Instrumentation
|
Gaseous Hydride Method with Atomic Absorption Detection |
Method Subcategory
|
Inorganic |
Method Source
|
|
Citation
|
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 |
Brief Method Summary
|
Organic arsenic-containing compounds are decomposed either by sulfuric acid-potassium persulfate digestion or by ultraviolet radiation. The arsenic so liberated, together with inorganic arsenic originally present, is subsequently reduced to arsine with sodium borohydride. The arsine is stripped from the solution with the aid of nitrogen and is then decomposed in a tube furnace placed in the optical path of an atomic absorption spectrometer. For additional information on the determination of arsenic in water, see Pierce and others (1976), and Fishman and Spencer (1977). |
Scope and Application
|
This method may be used to analyze water and water-suspended sediment containing at least 1 ug/L of arsenic. Samples containing more than 20 ug/L need to be diluted. This method may be used to analyze bottom material containing at least 1 ug/g of arsenic (NOTE 1). For samples containing more than 20 ug/g, use less sediment. NOTE 1. Do not use more than 100 mg sediment, because erratic results and large blanks will occur. Bottom material may be analyzed by this procedure after it has been prepared as directed in method P-0520. Both inorganic and organic forms of arsenic are determined. To determine only inorganic arsenic, omit the acid-persulfate digestion or the ultraviolet radiation. |
Applicable Concentration Range
|
1-20 ug/g |
Interferences
|
Since the arsine is freed from the original sample matrix, interferences are minimized. A detailed inorganic-interferences study showed that most trace elements at concentration levels of less than 300 ug/L do not interfere (Pierce and Brown, 1976). |
Quality Control Requirements
|
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). |
Sample Handling
|
Container Description: 500 mL Polypropylene bottle, wide-mouth. Treatment and Preservation: No treatment, preservation or special shipping requirements. |
Maximum Holding Time
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180 days |
Relative Cost
|
Less than $50 |
Sample Preparation Methods
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P-0520 |