Method 6040e Water Testing and Analysis - Regional Water Authority Lab

Method 6040E Testing

Method 6040E is used to analyze taste and odor compounds inclusive of 2-methylisoborneol (MIB) and geosmin. The method consists of three primary steps: a microextraction procedure, followed by the separation and then mass identification of the compounds.

Microextraction Procedure

The compounds are volatilized and collected using solid-phase microextraction (SPME) fiber. The fiber is coated with divinylbenzene-carboxen-polydimethylsiloxane cross-link. It is then placed in the headspace above the sample in a closed vessel. This allows the fibers to equilibrate with the aqueous sample.

Sample Separation and Identification

The fiber is then removed from the headspace and inserted directly into the heated injection port on the gas chromatograph (GC). This allows the analytes to desorb into the GC column. The column provides the separation of the analytes of interest from background interferences. Once this is complete, the compounds will be identified. A mass spectrometer is used to identify the compounds.

This technique allows the RWA Lab to be extremely accurate in the determination of the analytes and highly precise in the concentration of each compound.