EPA-OW/OST: 1698: Steroids and hormones in water, soil, sediment, and biosolids by HRGC/HRMS
Official Method Name
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Steroids and hormones in water, soil, sediment, and biosolids by HRGC/HRMS |
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Current Revision
| December 2007 |
Media
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VARIOUS |
Instrumentation
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Gas Chromatography with Mass Spectrometry Detection |
Method Subcategory
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Organic |
Method Source
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Citation
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U.S. Environmental Protection Agency, 2007, Method 1698: Steroids and hormones in water, soil, sediment, and biosolids by HRGC/HRMS: USEPA, Washington, DC, EPA-821-R-08-003, 69 p. |
Brief Method Summary
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This method involves solvent extraction of the sample, followed by cleanup with a layered alumina/Florisil column, and an option to remove sulfur using copper. Following cleanup, the target analytes are derivatized to make them sufficiently volatile for analysis by GC/HRMS. Quantitation is performed by isotope dilution and internal standard techniques, depending on the analyte and the availability of labeled analogs. |
Scope and Application
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This method is for determination of steroids and hormones in multi-media environmental samples by high resolution gas chromatography combined with high resolution mass spectrometry (HRGC/HRMS). |
Applicable Concentration Range
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Variable based on analyte and media |
Interferences
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Solvents, reagents, glassware, and other sample processing hardware may yield artifacts, elevated baselines, and/or lock-mass suppression causing misinterpretation of chromatograms. Specific selection of reagents and purification of solvents by distillation in all-glass systems may be required. Where possible, reagents are cleaned by extraction or solvent rinse. Proper cleaning of glassware is extremely important, because glassware may not only contaminate the samples but may also remove the analytes of interest by adsorption on the glass surface. All materials used in the analysis must be demonstrated to be free from interferences by running reference matrix method blanks initially and with each sample batch (samples started through the extraction process on a given 12-hour shift, to a maximum of 20 samples). Interferences co-extracted from samples will vary considerably from source to source, depending on the diversity of the site being sampled. Interfering compounds may be present at concentrations several orders of magnitude higher than the analytes in this method. The most frequently encountered interferences are humic and other acids, particularly in biosolids. Because very low levels of steroids and hormones are measured by this method, elimination of interferences is essential. The cleanup steps given in the method report can be used to reduce or eliminate these interferences and thereby permit reliable determination of the steroids and hormones. Each piece of reusable glassware should be numbered to associate that glassware with the processing of a particular sample. This will assist the laboratory in tracking possible sources of contamination for individual samples, identifying glassware associated with highly contaminated samples that may require extra cleaning, and determining when glassware should be discarded. |
Quality Control Requirements
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Each laboratory that uses this method is required to operate a formal quality assurance program. The minimum requirements of this program consist of an initial demonstration of laboratory capability, analysis of samples spiked with labeled compounds to evaluate and document data quality, and analysis of standards and blanks as tests of continued performance. Laboratory performance is compared to established performance criteria to determine if the results of analyses meet the performance characteristics of the method. |
Sample Handling
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Collect samples in plastic or amber glass containers following conventional sampling practices designed to obtain a sample that is representative of the material of interest. |
Maximum Holding Time
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Extract within 48 hours of collection and analyze extract within 40 days. Freeze sample to minimize degradation and increase holding time to 7 days; if frozen, extract within 48 hours of removal from freezer. Store sample extracts in the dark at less than |
Relative Cost
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$201 to $400 |
Sample Preparation Methods
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