USGS-NWQL: O-3104: Organochlorine and organophosphorous compounds, total recoverable
Official Method Name
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Organochlorine and organophosphorous compounds, total recoverable, gas chromatographic |
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Current Revision
| 1983 |
Media
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WATER |
Instrumentation
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Gas Chromatography with Electron Capture Detection |
Method Subcategory
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Organic |
Method Source
|
|
Citation
|
Methods for the Determination of Organic Substances in Water and Fluvial Sediments, Techniques of Water-Resources Investigations of the United States Geological Survey, Book 5, Chapter A3 Edited by R.L. Wershaw, M.J. Fishman, R.R Grabbe, and L.E. Lowe |
Brief Method Summary
|
Organochlorine and organophosphorous compounds are extracted from approximately one liter of water or water suspended-sediment mixtures with hexane. Organophosphorous compounds are determined on a gas chromatograph with flame photometric detectors. The extracts are then purified using adsorption chromatography on an alumina column. If PCB's, PCN's, and toxaphene are present, the extracts are further purified using a silica gel column. The organochlorine compounds are then determined by gas chromatography using electron capture detectors. |
Scope and Application
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This method is suitable for the determination of organochlorine insecticides, polychlorinated biphenyls (PCB's), polychlorinated naphthalenes (PCN's), and organophosphorous insecticides in water and water-suspended-sediment mixtures containing at least 0.01 ug/L of the analyte. |
Applicable Concentration Range
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0.01 ug/L - 0.6 ug/L (undiluted) |
Interferences
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(1) Contamination of samples, solvent, and carrier gases with target analytes (especially compounds common to environmental laboratories, like methylene chloride). (2) Contamination of samples with sulfur (primarily present in base-neutral fractions). (3) Septum bleed (compounds from the injection septum are analyzed with the sample). (4) Column bleed (compounds from column coating break down, decreasing column efficiency). (5) Ghost peaks (compounds adsorb strongly to the column and carry over to later runs). (6) Coelution of species. (7) Coextracted contaminants. (8) Phthalate esters interfere with detection of pesticides via electron capture detector. |
Quality Control Requirements
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Reagent water blank for each batch of samples. Calibrate daily with two point calibration. |
Sample Handling
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Description: 1 L Glass bottle, amber Treatment and Preservation: Bottle baked at 4oC by laboratory. DO NOT RINSE BOTTLE. Do not fill bottle beyond shoulder, as reagents must be added to the sample at the laboratory before analyses. Chill sample and maintain at 4oC; ship immediately. |
Maximum Holding Time
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Seven days from collection to extraction. |
Relative Cost
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$201 to $400 |
Sample Preparation Methods
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