[CPEO-MEF] Perchlorate detection

[CPEO Moderator <cpeo@cpeo.org>]

The study described below provides new information about efforts to
improve the detection of perchlorate at low concentrations. For a 4
megabyte PowerPoint presentation describing this work in more detail,
see http://www.cpeo.org/pubs/CLO4%20March%202003.ppt

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Title:  Analysis for Low Concentrations of Perchlorate in Groundwater by

Improved Ion Chromatography and LC/MS/MS

Lead Principal Investigators:  Lowell Coon, Mark Dymerski, & Larry
Penfold

Lead Principal’s Organization:  Severn Trent Laboratories
                                                     4955 Yarrow St.
                                                     Arvada, Colorado
80002
                                                     (303) 736-0142

Lpenfold@STL-INC.com

Abstract:

In November 1999, EPA published the ion chromatography (IC) Method 314.0
for the analysis of perchlorate in drinking water.  At the time, the
recommended maximum perchlorate concentration in drinking water was 18
ug/L.  More recent draft toxicity reports suggest that the recommended
maximum concentration should be lower, and some agencies are considering
concentrations as low as 1.0 ug/L.  In response to the interest in lower
quantitative levels the IC technology for Method 314.0 has been improved
significantly.  At the same time, techniques for analysis by liquid
chromatography tandem mass spectrometry (LC/MS/MS) have been developed.
Both methods offer improved sensitivity.  LC/MS/MS also provides
improved selectivity and the potential of direct analysis of direct
analysis in the presence of high levels of interferences.

The majority of samples that STL laboratories have been asked to test
for perchlorate are not true drinking waters, but are instead ground
waters from aquifers below Federal facilities and landfills.  Method
314.0 validation studies have not been published for these water types.
The purpose of this presentation is to present results of a method
performance study conducted on shallow groundwater collected at a
midwestern landfill.  The sensitivity, precision, accuracy, and
ruggedness of the two methods are compared.

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