DETERMINATION OF VOLATILE ORGANIC

COMPOUNDS IN WATER BY AUTOMATED HEADSPACE

GAS CHROMATOGRAPHY/MASS SPECTROMETRY

(SATURN II ION TRAP DETECTOR)

Disclaimer: This Standard Operating Procedure has been prepared for the use of the Robert S. Kerr Environmental Research Laboratory of the U.S.E.P.A. and may not be specifically applicable to the activities of other organizations.

I. Purpose: (Scope and Application)

This method is applicable to the confirmed identification and quantitation of purgeable volatile organic compounds (VOC) in water using gas chromatography/mass spectrometry (CC/MS) without the use of cryogenic focusing. It is based on EPA Method 524.2 which is used to determine over sixty VOC in drinking water. In addition to the analysis of aromatics and haloalkenes, haloalkanes, and haloaromatics, this method can also be used for the determination of petroleum hydrocarbons in contaminated water. The method is automated in that sampling and CC/MS analysis occur automatically after minimum input from the operator.

Approximately eleven analytical runs can be performed per eight hour day. The sample tray can be loaded with 50 samples which can be analyzed within thirty-eight hours.

This method is restricted to use by or under the supervision of analysts experienced in the use of gas chromatography/mass spectrometry and in the interpretation of chromatograms and mass spectra.

II. Summary of Method

A sample is sealed in a headspace vial and heated in the sampler's aluminum platen. The headspace gas in the vial is then sampled with a needle, flushed via a transfer line into a capillary column at 35ºC with no cryogenic cooling in the GC oven which provides compound separation. The volatile organics are identified and quantified by the GC/MS software system. Based on a 10 ml sample size a sample concentration in the range of 0.5 - 1,000 ppb can be determined. A method detection limit for 21 aromatic, haloalkane, haloalkene and haloaromatic compounds was determined at a concentration of 0.5 ppb and ranged from 0.06 to 0.5 ppb (See Table III).

III. References:

1. Methods for Determination of Organic Compounds in Drinking Water - Method 524.2 Measurement of Purgeable Organic Compounds in Water by Capillary Column Cas Chromatography/Mass Spectrometry. EPA/600/4-98/039, Dec. 1988.

2. Tekmar 7000 Headspace Sampler Operating and Service Manual, Tekmar Co., Cincinnati, OH.

3. Varian 3300/3400 Gas Chromatograph Operators Manual, Varian Analytical Instruments, Sugar Land, TX.

4. Saturn II CC/MS Operatoring/Reference/Applications Software Manuals, Varian Analytical Instruments, Sugar Land, TX.

5. Eichelberger, J.W., Bellar, T.A., Donnelly, J.P. and Budde, W.L., Determination of Volatile Organics in Drinking Water with USEPA Method 524.2 and the Ion Trap Detector. Journal of Chromatographic Science, Vol. 28, pp.460-467, Sept. 1990.

6. Definition and Procedure for the Determination of the Method Detection Limit - Revision 1.11, Code of Federal Regulations, 4OCFR Ch.I (7-1-91 Edition), Pt. 136, App. B, Environmental Protection Agency, pp. 554 - 555.

7. Environmental Chromatography Seminar 1992, Varian Analytical Instruments, San Fernando, CA.

8. RSKSOP-71 Revision No. 4, Date: 11/14/91, Steve Vandegrift, RSKERL, Ada, OK.

9. RSKSOP-127 Revision No. 1, Date: 05/28/92, Dennis Fine, RSKERL, ADA, OK.