United States Environmental Protection Agency Office of Research and Development
National Exposure Research Laboratory
FY02 Research Abstract
Government Performance Results Act (GPRA) Goal 2.1.7
APM78
Significant Research Findings:
Improved Method for CCL Related Chemicals in Drinking Water
for use in the Unregulated Contaminant Monitoring Rule
Hexahydro-l,3,5-trinitro-l,3,5-triazine (RDX) is a military explosive which
is known to have contaminated groundwater on and near military installations
where it has been used and stored. Historical disposal practices such as
open burning and detonation have contributed to environmental
contamination. The U.S. Environmental Protection Agency (EPA) has
classified RDX as a possible human carcinogen, and the Office of Water has
established a Lifetime Health Advisory for drinking water of 2 |ig/L. The
project focus was to develop a sensitive and specific analytical method for
the analysis of RDX in drinking water. Existing analytical methods for
measuring RDX are sensitive but not very specific. The need for this project
arose from the 1998 Contaminant Candidate List (CCL) which was
developed in response to the 1996 amendments to the Safe Drinking Water
Act. The CCL, published by EPA'S Office of Ground Water and Drinking
Water, identifies potential drinking water contaminants that might be
regulated by EPA at some future date. RDX was identified as a CCL
chemical on the 1998 list. The analytical method developed will be
proposed for the collection of nationwide occurrence data for RDX, and
possibly other explosives and related chemicals, in the next Unregulated
Contaminant Monitoring Rule (UCMR) scheduled for 2004. In the event that
a decision is made to regulate RDX in drinking water, the method could also
be used for compliance monitoring.
Research The research goal was to develop a method for measuring RDX and up to 16
Approach additional explosives, degradation products, and manufacturing by-products.
The initial method detection limit goal for RDX was 0.5 |ig/L, well below
the Lifetime Health Advisory of 2 |ig/L. As the project progressed, new
health information indicated that additional sensitivity may be necessary.
The approach involved developing procedures for (1) sample collection,
preservation, shipping and handling, (2) extraction and concentration of the
target analytes from an aqueous solution, (3) separation of the analytes
chromatographically, and (4) detection and quantification. Solid phase
extraction techniques were investigated for the extraction of explosives and
Scientific
Problem and
Policy Issues
National Exposure Research Laboratory — November 2002
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related compounds from aqueous samples. Gas chromatography/mass
spectrometry (GC/MS) was investigated for the chromatographic separation
and detection steps, because of its specificity.
Results and The analytical method developed from this research can be used to measure
Implications RDX and 13 additional explosives and related chemicals in drinking water
samples. The method procedure has been published as "USEPA Method
529: Determination of Explosives and Related Compounds in Drinking
Water by Solid Phase Extraction and Capillary Column Gas
Chromatography/Mass Spectrometry (GC/MS)." This method will be
proposed in the Federal Register for monitoring RDX and possibly other
explosives in the next Unregulated Contaminant Monitoring Rule (August
2004). The method detection limit for RDX ranges from 0.006 - 0.12 |ig/L
depending upon the various options selected within the method protocol.
The most sensitive procedure employs Selected Ion Monitoring (SIM)
GC/MS. These concentrations are expected to be below those needed for
drinking water monitoring, based upon currently available health effects
information. This method is an improvement over other published methods
for RDX in the following ways: (1) use of the mass spectrometer as the
detector provides positive identification of all method analytes without the
use of additional confirmatory techniques, and (2) the sample preservation
protocol ensures sample stability between the time of sample collection and
analysis. These improvements will significantly enhance the use of this
methodology in the collection of nationwide occurrence data to support
regulatory decision making for chemicals on the CCL.
This research project directly supports ORD's research under the
Government Performance and Results Act (GPRA) Goal 2 ("Clean and Safe
Water"), Objective 2 ("Ensure Safe Drinking Water and Recreational
Waters"), Sub-objective 7 ("Safe Drinking Water Act Research"). The
results of this project address GPRA annual performance goal (APG) 27
("Produce scientific reports on unregulated drinking water contaminants, in
support of the development of the next list of chemicals and pathogens for
potential regulatory action (i.e., Contaminant Candidate List #2). These
reports will help ensure that future drinking water regulations address the
contaminants of greatest public health concern"), and annual performance
measure (APM) 78 ("Improved methods for CCL related chemicals in
drinking water for use in the Unregulated Contaminant Monitoring Rule").
Research Publications resulting from this research:
Collaboration
and Publications Munch, J.W., "Analysis of RDX and other explosives by solid phase extraction and
GC/MS", Proceedings: American Water Works Water Quality Technology
Conference, Nashville, TN, Nov. 11-15, 2001.
Munch, J.W., "U.S. EPA Method 529: Determination of Explosives and Related
National Exposure Research Laboratory — November 2002
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Compounds in Drinking Water by Solid Phase Extraction and Capillary Column
Gas Chromatography/Mass Spectrometry (GC/MS)," 2002.
Copies of the method are available from the National Exposure Research
Laboratory, Microbiological and Chemical Exposure Assessment Research
Division, Chemical Exposure Research Branch, 26 W. Martin Luther King
Dr., Cincinnati, Ohio, 45268-1564.
Future Research Due to the success of the method development, no further research is planned
at this time. However, Method 529 will be proposed in the Federal Register
as the required analytical method in the Office of Ground Water and Drinking
Water's upcoming proposal for the Unregulated Contaminant Monitoring
Rule (planned for August 2004). When finalized, this regulation will require
a nationwide monitoring survey of selected CCL contaminants, including
RDX. Occurrence data from this survey will be used in the decision making
process for the possible regulation of RDX. In addition, other explosives
and related chemicals from Method 529 may be proposed for monitoring in
the next UCMR to help identify additional candidates for future CCLs.
Questions and inquiries can be directed to:
Jean W. Munch
US EPA, Office of Research and Development
National Exposure Research Laboratory
26 W. Martin Luther King Dr.
Cincinnati, OH 45268-1564
Phone: 513/569-7465
E-mail: munch.jean@epa.gov
Contacts for
Additional
Information
National Exposure Research Laboratory — November 2002
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