CWA and Degradation Product

Analysis for Matrix-Specific

Environmental Samples

Stuart A. Willison

U.S. EPA, National Homeland Security Research Center

National Environmental Monitoring Conference, San Antonio, TX

8/9/2013 1

U.S. Environmental Protection Agency

Outline

National Homeland Security Research

Program

• Drivers/Priorities

• Research Supporting EPA’s Response to Contamination

• Analytical Capability for CWAs in Target Matrices

(Sampling and Analysis)

• Analytical Capability for CWA Degradation Products in

Target Matrices (Sampling and Analysis)

2

EPA Homeland Security Drivers

and Responsibilities

3

Drivers

Bioterrorism Act (2002)

Homeland Security Presidential Directives (2003-2008)

National Response Framework (revised 2008)

Elements of:

– Comprehensive Environmental Response, Compensation and Liability Act

– Emergency Planning and Community Right-to-Know Act

– Clean Water Act

– Safe Drinking Water Act

– Oil Pollution Act

– Clean Air Act

Responsibilities • Protect water systems from attacks and

for detecting and recovering from successful attacks affecting water systems by leading efforts to provide States and water utilities guidance, tools and strategies. EPA is the federal government Sector Specific Agency (SSA) lead for water infrastructure.

• Decontaminate buildings and outdoor areas impacted by a terrorist attack by leading efforts to establish clearance goals and clean up.

• Develop a nationwide laboratory network

with the capability and capacity to analyze

for chemical, biological and radiological

agents for routine monitoring and in

response to a terrorist attack.

Food Safety

Modernization Act of 2010 “provide support for, and technical assistance to, State,

local, and tribal governments in preparing for, assessing,

decontaminating, and recovering from an agriculture or

food emergency”

Partner/Stakeholder Priorities

4

Research for Chemical Warfare Agents (CWAs)

and their degradation products in

environmental matrices to include:

• Analytical protocols

• Sampling different matrices (surfaces, soils, water)

• Stability studies for CWA and degradate standards

Increased laboratory capability and capacity

for CWA and degradate sampling/analysis.

5

Potential approaches

• Methods which can be applied to multiple labs for

workload distribution by the Environmental Response

Laboratory Network (ERLN) www.epa.gov/oemerln1

• High throughput sampling techniques and laboratory

analysis techniques, including automated or rapid

method capabilities

Meeting Lab Throughput

Requirements

Sampling and Analysis • To detect contaminants

• To determine extent of

contamination

Research to Support EPA’s Response to

Contamination Events and Site-Specific

Risk-Based Decisions

Informs Risk

Management Decisions

Risk assessment • To assess potential risk of

exposure, at harmful doses,

and identify exposure

pathways

7

• Analytes

– Tabun (GA), sarin (GB), soman (GD), cyclosarin (GF), sulfur

mustard (HD), nitrogen mustards (HN-1 & HN-3), lewisite (L), VX

and Russian VX (R-VX)

– Nitrogen mustard degradates

– Nerve agent degradates

Research Focused Towards

Chemical Warfare Agents

• Analytical Techniques

– Gas Chromatography/Time-of-Flight Mass Spectrometry

(GC/TOF-MS)

– Liquid Chromatography/Tandem Mass Spectrometry

(LC/MS/MS)

• Sample Types

– Soil

– Water

– Surface Analysis via Wipes

8

Residential Soil

(µg/kg)

Water

(µg/L)

Wipe

(ng/kg)

Agent MDL MDL MDL

GB 0.22 0.14 0.0030

GD 0.67 0.11 0.0017

GF 0.12 0.14 0.0047

HD 0.12 0.10 0.0015

VX 0.41 0.23 0.0080

Method Detection Levels (MDL) for G-series, HD and VX

by GC/TOF-MS

9

Residential Soil

(mg/kg)

Water

(µg/L)

Wipe

(ng/kg)

Agent MDL MDL MDL

GA 0.00033 0.13 11

HN1 0.00057 0.084 2.3

HN3 0.0016 0.72 35

R-VX 0.015 22 440

Method Detection Levels (MDL)

for GA, HN-1, HN-3 and R-VX by

GC/TOF-MS

Stability Study for Ultra-Dilute

CWA Standards

10

• One year stability study for 10 ppm standards of

GB, GD, GF, HD and VX • Flame-sealed ampoules - one year shelf-life

• Opened ampoules ~ 2-6 months depending on analyte

IMPACT:

• Dilute concentrations allow for shipment to ERLN labs

without special requirements.

• Provides stability of analyte standards over time in

order to ensure availability of standard and reduce

costs.

• Additional preservation study with only VX

Japan Subway Attack by Use of a Nerve

Agent

11

Kasumigaseki station was one of the many subway stations

affected during the attack

12

Sample Collection During an

Incident

13

31P NMR results: (a) 0.1 days, (b) 6 days, (c) 10 days,

(d) 14 days, (e) 17 days, (f) 20 days, and (g) 24 days

after the contamination.

Persistence of VX and Degradation

Product on Asphalt

Degradation profile of VX on ground asphalt.

Columbus et. al., Environ. Sci. Technol., 2012, 46, 3921−3927

Importance of Degradate Analysis

IMPACT:

• Identifies potentially toxic degradates, which may

persist

• Degradate analysis allows samplers to identify

potentially concentrated areas of concern for parent

compound

• Ensure remediation efforts can be completed

14

15

Challenges of Analysis Procedure

for Degradation Products

• Most CWA degradation products are not amenable to

gas-chromatography/mass spectrometry (GC-MS)

analysis without a derivatization step

• Step can be time-consuming with often times

incomplete conversion to the derivatized product

• Liquid chromatography/mass spectrometry (LC-MS)

offers advantages over GC-MS because polar analytes

can be directly analyzed

16

Optimization of Analysis Procedure

for Degradation Products

• Optimal eluents, chromatography separation, mass

spectrometric parameters were characterized with

low (ppb) detection limits*

• Optimal wipe investigated: cotton gauze, non-woven

polyester fiber cloth, pre-cleaned textile wipe, glass

fiber filter, and filter paper

• Surface evaluation included the following surfaces:

galvanized steel, glass, laminate, vinyl tile, treated

wood, painted drywall

* EPA Reports: EPA 600/R-11/143 and EPA/600/R-12/581

Hydrolysis Pathway of Nitrogen

Mustards in the Environment

17

18

LC-MS/MS Chromatogram of Wipe

Blanks*

* EPA Reports: EPA 600/R-11/143 and EPA/600/R-12/581

8/9/2013 19

Analyte TEA EDEA MDEA DEA

Wipe % Recovery

(n=7)

% Recovery

(n=7)

% Recovery

(n=7)

% Recovery

(n=7)

Approximate Spike

Concentration

(ng/mL)

10 50 10 50 10 50 10 50

Cotton Gauze 680 150 35 28 49 30 1600 430

Non-woven

polyester cloth 510 480 130 82 120 75 370 190

Alphawipe™ 9 23 18 22 17 21 10 18

Filter Paper 74 82 87 100 76 83 62 77

LC-MS/MS Chromatogram of Spiked

Wipe Samples

20

LC-MS/MS Chromatogram of Nitrogen

Mustard Degradation Products

Wipe 2 Wipe 1

Analyte Recoveries from Surface

Wiping*

21

Analyte TEA1 EDEA MDEA DEA1

Surface % Recovery

(n=7)

% Recovery

(n=7)

% Recovery

(n=7)

% Recovery

(n=7)

Laminate 81-99 47-71 66-80 71-81

Metal 20-46 49-56 54-74 62-79

Glass 91-150 31-36 52-61 59-81

Vinyl Tile 41-79 7-22 51-61 25-39

Painted

Drywall2 19 8 17 13

Wood2 2 1 2 1

1 Recoveries were subtracted from surface blanks for a

representative recovery of target analytes 2 Recoveries were only possible at highest spike concentration

* Results from surface wiping were performed using filter paper

22

LC-MS/MS Chromatogram of Nitrogen

Mustard Degradation Products*

* S.A. Willison, J. Chromatogr. A, 1270 (2012) 72–79

23

Hydrolysis Pathway of VX

in the Environment

24

Wipe Cotton

Gauze

Non-woven

Polyester

Cloth

Alphawipe™ Glass Fiber

Filter

Filter

Paper

Analyte %

Recovery

%

Recovery

%

Recovery

%

Recovery

%

Recovery

MPA 65 50 57 88 87

EMPA 67 54 57 89 89

IMPA 42 34 44 75 81

EHDMAP 56 59 74 75 78

PMPA 72 65 83 90 88

LC-MS/MS Chromatogram of Spiked

Wipe Samples

25

Laminate Surface

Filter Paper Cotton Gauze

Analyte %

Recovery

%

Recovery

%

Recovery

%

Recovery

Ionization

Mode ESI + ESI - ESI + ESI -

IMPA 67 98 72 79

MPA 102 55 122 35

EMPA 84 96 74 88

EHDMAP 57 67 53 71

PMPA - 85 - 79

LC-MS/MS Chromatogram of Spiked

Surface Samples

26 * manuscript in preparation

Enhancing Throughput for LC-MS/MS

Analytical Methods*

27

Summary

• Wipe selection may impact analysis capabilities due to

the presence of native contaminants/interferences

• Sampling and analysis capabilities for CWA and their

degradation products have been developed and tested

for a variety of target matrices

• Rapid analysis methods will enhance laboratory

throughput capability and capacity, improve detection

levels, and generate less waste

• CWA ultra-dilute stability studies ensure quality and

availability of standards during an incident

Acknowledgements

28

Co-authors/Collaborators: Romy Campisano1

Tonya Nichols1

Terry Smith2

Carolyn Koester3

Bob Streicher4

1U.S. EPA, National Homeland Security Research Center 2U.S. EPA, Office of Emergency Management 3Lawrence Livermore National Laboratory 4National Institute for Occupational Safety and Health

Website: www.epa.gov/sam

SAM 2012 Published: July 2012

DISCLAIMER: The U.S. EPA through its Office of Research and

Development partially funded the research described in this

presentation. It has been reviewed by the Agency but does not

necessarily reflect the Agency’s views. No official endorsement

should be inferred. EPA does not endorse the purchase or sale

of any commercial products or services.

Stuart Willison, Ph.D.

Research Chemist, Threat and

Consequence Assessment Division

Willison.stuart@epa.gov; 513-569-7253