USGS-NWQL: O-3104:  Organochlorine and organophosphorous compounds, total recoverable

  • Summary
  • Analytes
  • Revision
  • Data and Sites
Official Method Name
Organochlorine and organophosphorous compounds, total recoverable, gas chromatographic
Current Revision
1983
Media
WATER
Instrumentation
Gas Chromatography with Electron Capture Detection
Method Subcategory
Organic
Method Source
  USGS-NWQL
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
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
0.01 ug/L - 0.6 ug/L (undiluted)
Interferences
(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
Reagent water blank for each batch of samples. Calibrate daily with two point calibration.
Sample Handling
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
Seven days from collection to extraction.
Relative Cost
$201 to $400
Sample Preparation Methods