LAWRENCE Livermore has been among
the leaders in supporting national and world efforts to detect
chemical weapons and thwart their proliferation. In February, the
international Organisation for the Prohibition of Chemical Weapons (OPCW)
Livermores Forensic Science Center (FSC) to support its chemical
weapons are a growing threat to the security of the U.S. and its
allies, says Jeff Richardson, deputy program leader for the
Proliferation Prevention and Arms Control Program in Livermores
Nonproliferation, Arms Control, and International Security Directorate.
Putting the capabilities of FSC to work in the effort to
prevent the spread of chemical weapons is one more way the Laboratory
contribute to national and international security.
light of its demonstrated capabilities to analyze and characterize
samples, FSC was selected by the U.S. State Department in 2000
to become the second U.S. laboratory to support the OPCW, pending
by the OPCW. (The other facility is the U.S. Armys Edgewood
Chemical and Biological Forensic Analytical Center in Maryland.)
Under the terms of the Chemical Weapons Convention (CWC), the international
agreement banning chemical weapons that the OPCW oversees, all
samples must be analyzed at two OPCW-designated laboratories. In
addition, the U.S. Senate has mandated that all samples obtained
within the U.S. must be tested in the U.S. so that proprietary
belonging to American chemical manufacturers will be protected.
(See the box below.)
Chemical Weapons and
the Treaty That Bans Them
on the Prohibition of the Development, Production, Stockpiling,
and Use of Chemical Weapons and on Their Destruction
(commonly known as the Chemical Weapons Convention,
or CWC) defines chemical weapons as toxic chemicals
and their precursors. Chemical and biological weapons
have been referred to as the poor mans nuclear
weapons. This is particularly true of chemical weapons,
which are easily and affordably manufactured and can
inflict mass casualties.
are often grouped by their biological response. Nerve
agents include sarin, soman, and VX; blister agents
include mustard gas and lewisite; vomiting agents include
diphenylcyanoarsine; and tearing agents include CS gas.
warfare agents are similar to common industrial chemicals.
In fact, troops during World War I used several unmodified
industrial chemicals as weapons. For example, German
troops opened canisters of chlorine and let winds disseminate
the gas. Nerve agents, developed just before and during
World War II, are related chemically to the organophosphorous
insecticides and are among the most deadly: With some
of them, one drop on the skin can cause respiratory
failure and death.
The Geneva Protocol prohibiting the use of chemical
weapons in warfare was signed in 1925. Several nations,
including the U.S., signed with a reservation forswearing
only the first use of the weapons. The U.S. ratified
the protocol in 1975.
were used by Italy in Ethiopia and by Japan in Manchuria
and China prior to World War II, but no chemical weapons
were deliberately employed by the Allies or the Axis
powers during the war. Iraq used chemical weapons, including
mustard gas, during the IranIraq conflict of 1982
to 1987. Evidence indicates that it used chemical weapons
within its own boundaries in 1988 when it killed about
5,000 Kurds in Halabja with a combination of mustard
gas and the nerve gases sarin, tabun, and VX.
Until 1985, virtually
all uses of chemical weapons had been as tactical weapons
by nations. Then, in a terrorist attack, the Japanese
cult Aum Shinrikyo released sarin gas in a Tokyo subway,
killing 12 people and injuring more than 5,000. Currently,
thousands of toxic chemicals could be used as chemical
weapons. Many can be manufactured in existing chemical
plants or individual laboratories.
The only toxin
to exist naturally is ricin, made from the ubiquitous
castor bean plant. British authorities found traces
of ricin, for which there is no antidote, in a raid
on a London apartment in January 2003. Instructions
for making ricin have been found in the possession of
several suspected terrorists and fighters in Chechnya.
CWC Extends Globally
The CWC is a
global treaty that bans the development, production,
use of chemical weapons. Parties to the treaty are
obligated to destroy their chemical weapons and production
facilities within a specified period of time. They also
must not assist other states in the production of chemical
weapons. (The U.S. has been destroying its stockpile
of chemical weapons at a cost of many billions of dollars.)
began in 1980 as part of the United Nations Conference
on Disarmament. The CWC went into effect on April 29,
1997, four days after the U.S. signed. Currently, more
than 145 nations have signed the treaty, although nations
such as Iraq and North Korea have not.
The CWC places
controls on toxic chemicals and their precursors, which
are listed on three schedules according to their toxicity,
military and commercial utility, and risk. Schedule
1 lists military agents with no or low commercial use,
such as nerve agents and mustards as well as their direct
precursors. Schedule 2 lists high-risk precursors and
toxic chemicals that are not produced in large quantities
for commercial use. Schedule 3 lists dual-use chemicals,
some of which have been used as weapons or precursors
but which are produced in large quantities for purposes
not prohibited by the CWC. The treaty allows states
to produce an aggregate of 1 metric ton or less of Schedule
1 chemicals for research, medical, pharmaceutical, and
The CWC is the
first arms control and nonproliferation treaty to widely
affect the private sector. Although the U.S. does not
manufacture chemical weapons, it does manufacture, use,
import, and export a number of dual-use chemicals that
could be used to produce chemical weapons. U.S. companies
engaged in activities involving certain chemicals may
be required to submit reports to the Department of Commerce
and may be subject to inspections.
The CWC is implemented
by the Organisation for the Prohibition of Chemical
Weapons (OPCW), which is headquartered in The Hague,
Netherlands. The OPCW has almost 500 employees, including
a multinational corps of inspectors. Any treaty party
that suspects another signatory of conducting activities
prohibited by the CWC has the right to ask for a challenge
inspection of the suspect site. The analysis of samples
may be done at the suspect site, but samples can also
be transferred to approved OPCW laboratories for additional
When the U.S.
Senate ratified the CWC, it implemented a mandate, Condition
18, which states that no sample taken on U.S. soil shall
leave the U.S. for analysis during an OPCW inspection.
However, it is an OPCW requirement that two OPCW-accredited
laboratories must analyze the samples and provide independent
correlation. The two accredited U.S. laboratories are
the U.S. Armys Edgewood Chemical and Biological
Forensic Analytical Center and Livermores Forensic
to Livermore chemist and principal investigator Armando Alcaraz,
FSC was originally selected by the State Department because of
Laboratorys advanced environmental controls and physical
security and FSCs demonstrated capabilities in detecting
and analyzing minute traces of unknown materials. Alcaraz also
previous participation in international exercises to detect chemical
agents and FSC chemists work with colleagues at Edgewood.
(See the box below.)
Chemical Weapons Work
Is Part of FSC Expertise
certified by the Organisation for the Prohibition of
Chemical Weapons (OPCW) operates as part of Livermores
Forensic Science Center (FSC). Founded in 1991, FSC
offers a comprehensive range of analytical expertise
to counter terrorism, aid domestic law enforcement
and homeland security, and verify compliance with international
treaties and agreements.
centers human and technological
resources have made it among the leading
facilities for collecting and analyzing
virtually any kind of evidence, some
of it no greater than a few billionths
of a gram. FSC has expertise in ultratrace
chemical and isotopic analyses of nuclear,
inorganic, organic (chemical warfare
agents, illegal drugs, explosives), and
biological materials (toxins, DNA).
also develops new technologies for detecting
and characterizing the source of weapons
materials. A major effort is adapting
forensic analysis technologies for field
use. For example, FSC scientists have
shrunk the standard gas chromatographmass
spectrometer so it fits inside a wheeled
suitcase. (See S&TR, April
2002, Forensic Science Center Maximizes
the Tiniest Clue.) When necessary,
the center draws upon experts in Livermores
Chemistry and Materials Science and Nonproliferation,
Arms Control, and International Security
and law enforcement agencies call upon
FSC for analyses beyond the capabilities
of their in-house laboratories and for
interpreting samples demanding unusually
high-quality forensic analyses. In 1998,
the Federal Bureau of Investigation named
FSC as the bureaus West Coast support
laboratory. As part of the OPCW accreditation
process, FSC in November 2001 obtained
an International Organization for Standardization
certification in the field of chemical
testing by the American Association for
Livermore Joins Select Group
joins about 15 other laboratories around the world that have been
certified by the OPCW. The purpose of these laboratories is to test
samples collected by OPCW inspectors from chemical plants and other
sites to determine whether the samples contain scheduled chemicals
(chemical weapons or their precursors) or their decomposition products.
(The annex to the CWC has three schedules, or lists, of banned and
monitored compounds: Schedule 1 compounds are the most toxic, and
Schedule 3 compounds are less toxic or are dual-use chemicals.)
To date, no samples have been officially collected from any sites.
The only samples examined by the OPCW-certified laboratories have
been those prepared for proficiency tests and exercises.
achieved its OPCW certification by passing three grueling proficiency
tests. The tests involved the analysis and characterization of samples
containing combinations of extremely dilute amounts of chemical
warfare agents, precursor chemicals, and decomposition products
as well as other chemicals included to complicate or obfuscate the
analysis. The tests that led to accreditation took place in November
2001, April 2002, and October 2002. Different OPCW-designated laboratories
formulated the test samples and graded FSC findings.
proficiency tests used samples that simulated those the OPCW inspectors
might send to Livermore for analysis. The test samples typically
consisted of soil, a water-based solution, and an organic-based
solution, each contained in sealed glass vials. One test sample
looked like milk, but in reality was an emulsion of aqueous and
organic phases, each containing suspected products.
Each vial contained one or more scheduled compounds that had to
be identified. For each test, the Livermore team was given 15 days
to analyze the samples and report its findings.
Background information was also provided on the simulated inspection
scenario of the tests. For example, in one scenario, the note claimed
that the samples were taken during an inspection of a foreign pesticide
plant. Inspectors had supposedly obtained the samples from different
locations around the plant, including soil from outside the plant
because it might contain degradation products from illicit manufacturing
of chemical weapons.
certified by the Organisation for the Prohibition of Chemical
Weapons must be capable of detecting minute amounts of chemical
warfare agents, precursor compounds, and their decomposition
Analysis Plan Is Well-Rehearsed
to the three proficiency tests, the Livermore team of chemists now
has a well-rehearsed plan for analyzing an OPCW sample. A large
conference room is transformed into a war room. Whiteboards
on the walls are covered with flow diagrams and notes about possible
compounds contained in the samples. Its a pretty intense
time, but were very focused, and we have outstanding teamwork,
says Hugh Gregg, coprincipal investigator.
the 15 days of analysis, Rich Whipple prepares samples and Alcaraz
and Gregg lead the analysis, aided by Robert Maxwell and Greg Klunder.
Andy Vance, John Reynolds, and Phil Pagoria synthesize compounds
used to confirm the presence of suspected compounds, and Tuijauna
Mitchell-Hall provides quality control.
emphasizes that team members follow all applicable safety and security
requirements for analyzing and synthesizing dilute chemical agents.
In some cases, he says, the solvent is more hazardous than the target
compounds because any chemical warfare compounds in the samples
have been diluted to extremely low concentrations.
occasionally contain emulsions of different layers, with
each layer containing suspected chemical warfare agents,
precursors, or decontamination products.
team uses a variety of analytical techniques, including gas chromatography,
mass spectrometry, atomic emission detection, gas chromatograph
flame photometric detection, chemiluminescense, infrared spectrometry,
liquid chromatography, inductively coupled plasma mass spectrometry,
nuclear magnetic resonance, and capillary electrophoreses. With
three nuclear magnetic resonance machines and more than 12 gas
analyzers at their disposal, the team has one of the worlds
best-equipped labs to analyze exceedingly small amounts of material.
use all the instruments because each gives us unique information,
says Gregg. For example, FSC recently acquired a gas chromatograph
capable of infrared detection because it yields structural information
about a compound. The OPCW requires that at least two different
analytical techniques be used for positive identification, and the
Livermore team strives to obtain confirmation from three or four
instrument is the gas chromatographmass spectrometer (GCMS),
which can detect ultratrace quantities of organic compounds weighing
a billionth of a gram or less. A few microliters of a sample are injected
into the GCMS, where the sample is vaporized and the sample
components are separated and analyzed.
|A large conference
room is transformed into a “war room” for discussions
and posting flow diagrams and notes about possible chemical
warfare compounds contained in samples.
Looking for Suspicious Elements
of the most important first steps in analyzing OPCW samples is doing
quick screens with the GCMS and element-specific detectors
to look for a few key elements that indicate the possible presence
of chemical warfare compounds. For example, lewisite contains arsenic,
sarin contains phosphorous and fluorine, and VX contains phosphorous,
nitrogen, and sulfur.
notes that just as important as finding actual chemical warfare
agents is finding the chemicals that are associated with their manufacture.
Many precursors are listed on Schedule 1 because they are unique
to the manufacture of chemical weapons. The CWC list of scheduled
chemicals includes tens of thousands of chemicals, most of which
have never been synthesized or characterized but are thought to
be as deadly as their well-known analogs. Identifying these designer
agents is an extremely difficult but necessary part of the job.
products of chemical agents also qualify as smoking guns.
The chemists must keep in mind the possible products that could
be found, for example, in the wastes from a chemical or pesticide
manufacturing plant. And the team must anticipate the products that
might result from decontamination procedures, as might happen if
someone used bleach or another strong oxidizer to eliminate traces
of illegal chemical agent manufacture. The team must also consider
degradation products resulting from environmental factors such as
sunlight and rain. Some chemical agents are stable while others,
such as the nerve agent sarin, break down easily.
Whipple notes that the sample solutions may also contain agents,
such as dirty diesel oil, that mask the target compounds present
in vanishingly small quantities. In one case, when the diesel oil
was carefully removed, the chemists found trace amounts of a chemical
warfare agent precursor.
Chemist Armando Alcaraz logs in a proficiency test sample.
(b) Chemist Bob Maxwell holds a sample in a tube that will
be placed in a nuclear magnetic resonance instrument (in
background). (c) Alcaraz injects a microliter of sample into
a gas chromatograph–infrared spectrometer system. (d)
Chemist Hugh Gregg uses solid-phase extraction cartridges
to clean a sample of hydrocarbon compounds that might mask
a chemical warfare agent.
Watching for Red Herrings
Finally, the team must be ready to locate and identify any of thousands
of possible compounds added to the samples as red herrings. These
compounds are not found in any chemistry reference because they
were created just for the test in an effort to fool the analysts.
They are often similar or identical in molecular weight and elemental
composition to well-known chemical warfare compounds.
compounds will look like a Schedule 1 compound, but if we report
it as such, we fail the test, says Vance. One such compound
contained sulfur, phosphorous, and nitrogen, good indicators of
a nerve agent, and the molecular weight was in the ballpark for
a well-known nerve agent. With the aid of multiple syntheses and
nuclear magnetic resonance analysis, the team figured out its structure,
which was different from that of any nerve agent (and therefore
not scheduled). The compound had been made by an OPCW laboratory
to confuse chemists analyzing the sample.
notes that OPCW has provided a database of thousands of compounds,
complete with molecular weight, structure, and what the GCMS
spectrum should look like. In addition, the GCMS will suggest
the identity of a compound based on the 2,000 to 3,000 compounds
in its library. However, the instrument is not foolproof because
more than one compound can have the same molecular weight and elemental
result, once the team suspects the presence of a particular compound,
it must obtain a reference sample, either from its storehouse of
500 to 1,000 stock chemicals or by synthesizing the compound. Either
way, the reference is then screened by the same instruments to make
sure it gives identical readings.
points out that synthesizing the suspect chemicals poses no health
or safety risk because chemists work in a special hood and use gloves.
More importantly, they only synthesize extremely small amounts of
material, never exceeding a concentration of 1 milligram per milliliter
and a total of 10 milliliters of solution.
the GCMS separates compounds, the synthesis chemists arent
concerned about purifying their product, which saves valuable time.
They also arent concerned about yield. If we have only
fractions of a microgram, the GCMS will find it, Vance
says. The hard part is that doing things as fast as possible
and not caring about yield is counter to my experience on other
projects in which the focus was on maximizing yield and purity.
the synthesis effort are parallel synthesis techniques. A parallel
synthesis instrument can perform up to 20 simultaneous reactions
in temperature- and atmosphere-controlled reaction vessels. Vance
can make multiple compounds that meet molecular weight and elemental
composition requirements and then analyze all of them to find one
notes that as Day 15 approaches, We feel the pressure. Were
always thinking, Did we miss something? To answer
that question, the team invites other Livermore chemists to a meeting
about three to four days before the deadline to review its analysis
work and give comments and suggestions. The meeting, says Gregg,
shows that this is a real team effort, not just one person.
Finally, the team sends its report, complete with instrument readouts
and flow diagrams, to OPCW headquarters, where it is forwarded to
a certified lab for grading. Gregg notes that OPCW has taken Livermores
report format and made it the standard for all designated laboratories.
chromatograph of a sample was produced by a gas chromatograph–mass
spectrometer. Hydrocarbons could be masking trace amounts
of chemical weapon agents. (b) Once the hydrocarbons are
removed, the analysis reveals the presence of a compound
that is a precursor to a chemical warfare agent.
First Exercise Tests System
February, the team participated in OPCWs first exercise designed
to test all the procedures related to using the designated laboratories,
including procedures for shipping and analyzing authentic samples.
Not part of the proficiency tests, the exercise involved samples
from a mock inspection site in Singapore that had been sent to OPCW
headquarters in The Hague, Netherlands. OPCW added a quality control
sample and a blank solution and placed them in a specially designed
stainless steel case for transfer by commercial shippers to participating
laboratories in Livermore, South Africa, and Britain.
sending the samples to Livermore, OPCW notified the U.S. State Department,
which notified Alcaraz and Gregg. Upon hearing from Alcaraz that
FSC was ready, the OPCW sent the samples to Livermore. We
wanted to discover any customs and shipping problems that could
come up with officially labeled samples from OPCW, says Alcaraz.
Because of paperwork and customs issues both in Europe and at the
Los Angeles airport, the samples arrived a week later than expected.
inspector from Zimbabwe was on hand at Livermore to verify the samples
intact seals and weights. OPCW rules also allow a representative
from the nation where the samples are taken to monitor the analysis.
As with the proficiency tests, the Livermore team had 15 days to
send in their analysis but finished the task in just one week. This
sample handling exercise was beneficial to OPCW and the U.S. Potential
and actual pitfalls in collecting, transporting, and analyzing authentic
samples and reporting the results have been identified and are being
Vance uses parallel synthesis techniques to quickly prepare
reference compounds and try to match them to what the team
suspects are chemical warfare agents, precursors, or decontamination
anticipates that FSC may receive samples for analysis several times
a year from OPCW inspections. Samples could contain just about
suspect material, including water, soil, gasket material, and even
chips of concrete. As with the test samples, real samples will
diluted by inspectors before they are forwarded to an OPCW-designated
the meantime, the team is doing data validation work for the OPCW-developed
libraries of scheduled chemicals. These libraries
are used by inspectors with portable GCMS instruments in the
field and by designated laboratories performing analyses. Livermore
chemists are evaluating the spectral data to make sure they are
accurate. In addition, FSC, like all OPCW-designated laboratories,
is expected to maintain high scores (at least two As
and a B on yearly proficiency tests) to keep its certification.
notes that FSC would like to make its chemical warfare agent analysis
resources available to other government agencies. For example,
he suggests the center could aid homeland security by providing
technical support to first responders who suspect chemical agents.
Agencies such as local health departments and the Environmental
Protection Agency do not have expertise identifying chemical warfare
agents, he says. Fortunately, Lawrence Livermore is certified to
do the job.
Key Words: chemical weapons, Chemical Weapons Convention (CWC),
Forensic Science Center (FSC), Organisation for the Prohibition
of Chemical Weapons (OPCW).
For further information contact Armando Alcaraz (925) 423-6889
a printer-friendly version of this article.