The United States Army is poisoning the people of Veolia Texas with exhaust from its nerve gas wast incinerator. The following analysis and the referenced web posting describe serious problems with the technology used by the Army and its subcontractors to ensure that chemical weapons are not leaking into the air and poisoning the public. One of these chemicals, VX, can persist in the environment up to two weeks under the right conditions. If you think that this is not your concern, ask yourself how far the wind can blow in two weeks.
Analysis of
‘Deficiencies of Detecting Nerve Gas in Air’
report found on
http://cryptome.org/cryptomb20.htm, nerve-gas.htm
posted August 12, 2006
Abstract
The United States is obligated under
the terms of the Chemical Weapons Convention to destroy all of its chemical
weapons.
This document is an in-depth review
of a report located at http://cryptome.org/cryptomb20.htm,
nerve-gas.htm. The report details a number of extremely
serious problems with the methods that are used to monitor the air in the
vicinity of chemical weapons storage or handling facilities for the presence of
chemical weapons, specifically the nerve gases GB and VX, which is the most
dangerous nerve gas in the stockpile.
The following major points of
failure of the monitoring technology are made clear in the report.
1) The method has a degree of variability
in agent detection that precludes its effective use for measuring agent levels,
on the order of 1000-fold.
2) The sampling tubes used in the method
are very fragile and improper use or preparation makes the tubes useless for
agent monitoring, and damaged tubes are currently being used at monitoring
sites.
3) The conversion pads used for the
detection of VX nerve gas can cause the level detected to be significantly
underestimated due to competing side reactions that form products that are not detected
by the instrumentation.
4) The sampling tubes in daily use at one
of the sites engaged in agent destruction were found to be significantly
degraded. Agent spiked onto the tubes
was not detectable at levels many times the danger level.
As a result, it is clear that the
methods used to monitor the safety of the chemical weapons are so flawed as to
preclude effective monitoring for the presence of chemical weapon vapors in the
air.
There are eight sites scattered
around the continental U.S.
where these agents are stockpiled, and many more places such as abandoned
training sites and firing ranges where chemical munitions are known or
suspected to exist.
This report calls into question all
of the reassurances of the US Army and its contractors have made as to the
safety of these sites. It is apparent
that there has never been effective safety monitoring at these facilities, and
that anyone living near or up to several hundred miles down wind of these
installations is and has been in grave danger of poisoning.
The physiological effects of low
level exposure to these chemicals are poorly understood. There is a hypothesis that low level agent
exposure is the cause of ‘Gulf War Syndrome’, and there is an ever increasing
body of scientific evidence that exposure to chemicals of this class are
responsible for human diseases including asthma, lupus and cancer.
This report makes clear that we all
have reason to be very concerned that we and or our loved ones have been
negligently exposed to these chemicals by people motivated by the basest of
human vices, greed. This report should
be seen as a call to action to stop this quietly progressing environmental
catastrophe. We must all take a stand
and demand that this atrocity be stopped.
Introduction
This report was posted to the
Cryptome website on August 12 of 2006.
It details a number of significant problems that the air sampling
techniques that are used by the U.S. Army and its contractors to determine
whether or not the chemical weapons in storage awaiting destruction are leaking
their contents into the environment.
The report details the failures of
the methods by way of a series of experiments and observations made in the
course of a project designed to evaluate a new scientific instrument for use in
chemical weapons monitoring work. The
new instrumentation under evaluation was found by the authors of the report to
be suitable for the task and was determined to be capable of detecting the
presence of the agents at very low levels.
The authors report though that
numerous problems were encountered in the use of the long established and
trusted sampling methods and devices.
These problems were clearly identified and defined by the authors
through a series of experiments designed to identify the causes of a number of
unusual observations made during the conduct of the project.
The U.S. government is currently
destroying accumulated stocks of chemical weapons that date back to the First
World War. The Chemical Weapons
Convention (CWC) entered into force in 1997 and required signatory states to
destroy their chemical weapons by 2012.
As in all Federal government
efforts, the deadline for destruction has been delayed and the costs of the
project have multiplied.
At the time that many of the
weapons were assembled it was anticipated that they would be used relatively
soon after manufacture, they were not intended to be stored for many years. These
delays place the public at increased hazard due to the physical and chemical deterioration
of these weapons.
The sampling method is referred to
DAAMS, and it is related through commonality of technology to ACAMS and MINI-CAMS. DAAMS stands for Depot Area Air Monitoring
System, ACAMS stands for Automated Chemical Agent Monitoring System and
MINI-CAMS stands for MINIature Chemical Agent Monitoring System. DAAMS, ACAMS and MINI-CAMS are the benchmark
techniques used by the United States Army and its contractors to monitor the
air in the areas where chemical warfare agents are stored, handled and
ultimately destroyed.
Background
As a first step toward what
ultimately became an effort to comply with the Chemical Weapons Convention, the
U.S. government withdrew all of its chemical weapons from Western Europe in the
early 1980’s and transported them to Johnston Island in the middle of the
Pacific Ocean. The government, in
partnership with a number of contractors and subcontractors, then began
building a specialized incinerator on the island that was designed to robotically
disassemble the munitions, extract and destroy the toxic payload and destroy
residual agents and explosives in the incinerator.
The Johnston Island
project, known as JACADS, was intended to test and perfect the methods for
monitoring, storage and destruction of the increasingly dangerous chemical
filled munitions. At the time of the
commissioning of JACADS it was planned that, once the technology and techniques
had been perfected, additional incinerators would be constructed throughout the
continental United States
to destroy stockpiles of chemical munitions at eight Army storage locations.
This multiple site strategy was
adopted because many of the chemical munitions in the stockpile are severely
deteriorated and are therefore unsafe to transport to a central location for
destruction.
These locations include Deseret Chemical
Depot in Utah, Pine Bluff
arsenal in Arkansas, Umatilla Chemical Depot
in Oregon, Anniston Army Depot in Alabama, Bluegrass Army Depot in Kentucky,
Aberdeen Proving Ground in Maryland, Pueblo Chemical
Depot in Colorado and Newport Chemical Depot
in Indiana. Of these, Aberdeen Proving Grounds has completed
all agent destruction activities.
In addition there are a number of
other locations throughout the United
States that hold so called ‘non-stockpile’
chemical warfare agents. These include
training centers (troops were exposed to low concentrations of these agents so
they could recognize them by smell!), research labs, waste dumps and firing
ranges.
Notable among these sites is the ongoing
project on the grounds of American University in Washington
D.C. to remove abandoned chemical
munitions and related materials dating from World War One. These dumped munitions were re-discovered in
the course of construction activities on the grounds of what had been a U.S.
Army facility.
Significant numbers of filled
chemical munitions and bulk containers of chemical warfare agents have been
dumped in the oceans of the world. Large
sites include Ordinance Reef off of the coast of Hawaii,
a number of sites off of the coast of New Jersey,
several sites off of the coasts of California,
Texas and Louisiana,
and the huge dumping grounds in the Baltic Sea used by the Allies after the
defeat of Germany
for the disposal of Nazi chemical weapons.
The Soviet states have also dumped agent and agent filled munitions in
various places in the oceans of the world.
These oceanic dumping sites
currently present significant hazards.
For instance, many of the states bordering the Baltic have specialized
emergency response crews that remediate agents that either wash up on shore or
are accidentally captured in fishing nets.
There are numerous instances of fishermen being exposed to free agent escaped
from various dumped items and munitions caught up in trawling apparatus. It is known that the containers that were
dumped are leaking, as many times exposure to fishermen is due to the presence
of free clumps of semi-solidified sulfur mustard (known as H or HD). Occasional encounters with Lewisite, an
arsenic containing blister agent, have also been reported both on land and at
sea. Recently Ordinance Reef in Hawaii has come under additional
scrutiny due to munitions being washed ashore by storms.
China also is currently working to
find, remove and neutralize chemical agent filled munitions at a number of
sites that were left behind by the Imperial Japanese Army during World War Two. The members of the former Soviet
Union are also working to destroy the nearly 4.5 million tons of
chemical weapons produced during the cold war.
Large numbers of the munitions are
unstable due to corrosion of the metallic components of the weapons caused by
the agents and impurities that were byproducts of their manufacture. Many of the weapons systems include explosive
bursting charges and some contain propellants.
For instance there are M55 rockets
in the U.S.
inventory that were filled with the most potent nerve agent ever produced in
quantity, VX. The VX contained small
amounts of hydrogen fluoride as a byproduct.
The hydrogen fluoride corroded the unprotected aluminum agent reservoirs
in the rockets, leaving them susceptible to leaking. M55 rockets also contain bursters and
propellant. The VX can chemically react
with the chemicals in the explosives and fuel to produce fires and low order
explosions. Since these weapons are
permanently assembled, the bursters and propellant can not be easily
removed. Thus the M55’s are all in a
dangerously unstable state, liable to leak, catch fire or explode at the
slightest provocation. Many thousands of
M55s were manufactured and all have been in storage for more than 30
years. Each M55 is thus a ticking time
bomb, ready at any provocation to kill anyone within range.
The chemical warfare
agents
The primary agents in storage in
the United States
include the nerve agents GB and VX, and the blister agent HD. Smaller amounts of other agents are also
present but these three represent the vast majority of what is held in the U.S. chemical
weapons stockpile.
GB and VX are nerve agents. Their primary mechanism of acute action is to
inhibit the activity of the enzyme acetylcholinesterase. Acetylcholinesterase is a vital component of
nerve impulse signal transmission, which when inhibited causes muscles to enter
a state of uncontrolled contraction, much like the results of the disease
tetanus. This spastic state paralyzes
the muscles used in respiration and the victim of poisoning dies by
suffocation.
GB is a ‘non-persistent’
agent. GB has a relatively low boiling
point and evaporates readily at room temperature. It is called non-persistent because after a
relatively short time it has all evaporated and blown away on the wind.
VX on the other hand is a
‘persistent’ agent. VX has a relatively
high boiling point causing it to evaporate much more slowly than does GB. This causes the VX to remain for a much
longer time in the area of dispersal, slowly evaporating over periods of two
weeks or more, creating a toxic cloud over the area. GB and VX also kill by being absorbed through
the skin.
Of the two, VX is much more lethal,
with as little as ten milligrams, one eighth the amount of active ingredient
present in a children’s aspirin, being enough to kill an adult in 10 minutes or
less. Thus given its persistence in the
environment, high toxicity, chemical stability and nearly odorless nature VX is
an extremely dangerous material.
The nerve agents owe their origin
to research conducted between World War One and World War Two by German
scientists who were studying insecticides.
During these investigations the researchers noted that several of the
molecules that they made were exceptionally toxic to mammals. These findings were duly reported and
ultimately the information attracted the attention of the German military
government. As a result three of the
organophosphates, called by the Germans Soman, Sarin and Tabun, were developed
for military applications. Germany
produced and weaponized, but never used these agents during World War Two.
VX was invented by the British
after World War Two and the technology was traded to the United States
in exchange for nuclear weapons technology.
HD is distilled sulfur
mustard. Sulfur mustard was one of the
chemical weapons used during the First World War.
Sulfur mustard is a simple molecule
that is quite reactive chemically.
Sulfur mustard inflicts injury on tissue by chemically reacting with it
causing what can be thought of as a chemical burn. Sulfur mustard burns all exposed surfaces,
the skin, eyes, and lungs being the primary sites of action. In sufficient quantities sulfur mustard
causes extreme blistering of the skin resulting in the formation of large fluid
filled blisters. Sulfur mustard also can
cause blindness and death due to its burning action on lung tissue, causing
chemical pneumonia, where the lungs fill with fluid due to damage to the lining
of the lungs.
Sulfur mustard was first
synthesized in the early 19th century, but its potential as a weapon
was not realized until the latter part of that century.
World War One was the first conflict
in which chemical weapons were used on a large scale. Among the most common agents used were, in
addition to mustard, chlorine gas, phosgene, Lewisite and chloropicrin. Prussic acid (hydrogen cyanide) was found to
have minimal tactical utility due to its rapid dispersal and dilution under
battlefield conditions, even though it possessed a high order of toxicity.
All of the other commonly used agents
exerted their toxic effects by direct corrosive or irritant action on the tissues
of the victims. Deaths were due to gross
intoxication with large quantities of agent and/or pneumonia secondary to the
lung tissue damage caused by exposure. Most
exposed victims suffered varying degrees of dermal burning and damage to the
eyes and lungs.
Physicians treating victims of
sulfur mustard during the First World War
also noted that in cases where exposed patients also had cancers, that the
tumors were significantly damaged by the effects of the agent. These observations lead to experiments that
ultimately produced the first chemotherapeutic drugs for the treatment of
cancer. For instance, mechlorethamine,
cyclophosphamide (Cytoxan), melphalan and other drugs used in the treatment of
various cancers are derivatives of sulfur mustard.
As everyone knows, cancer chemotherapy
drugs have significant side effects, the most visible of which is hair
loss. This is because these agents
affect rapidly growing cells (cancer) more than they do slowly growing cells
(normal). The cells that generate the
hair shaft are rapidly growing and therefore are more strongly effected, and
killed, by these drugs, causing the patients hair to fall out. Other types of cells affected by these agents
include the lining of the gastrointestinal tract, causing severe diarrhea and
pain due to ulceration, the reproductive organs, causing in many cases
sterility and skin damage.
Less known is the fact that
treatment with any of these drugs significantly increases the chances that the
patient will later develop a new cancer.
This is because these agents can also react with and damage DNA, causing
mutations in the DNA that can result in the damaged cells becoming cancerous. Thus any exposure to mustard type chemicals even
at very low levels can result in the formation of cancer.
Given this fact one may ask why
treat cancer patients with these agents.
The answer is that these agents were at the time the only effective
drugs and that in some cases patients were actually cured, thus the risk was
acceptable.
Given the advances in our knowledge
acquired since the introduction of these drugs we have developed a large number
of less toxic and hazardous treatments and techniques that have reduced but not
eliminated the use of these drugs in the treatment of cancer.
Destruction
technologies explained
In the late 1980’s and early 1990’s
the government commissioned a number of scientific advisory panel meetings to
discuss the advantages and disadvantages of various proposed destruction
technologies. Among those considered
were incineration, chemical neutralization using solvated electron technology
(SET), super critical water oxidation (SCWO), oxidation by mixing with super
tropical bleach or sodium hypochlorite, and alkaline hydrolysis through mixing the
agents with concentrated solutions of sodium hydroxide at elevated
temperature. All of the techniques were
investigated, with incineration chosen as the primary method and sodium
hydroxide hydrolysis as the secondary method of destructive
demilitarization.
The incineration plants used for
chemical weapons destruction include secured areas for safe disassembly of the
assembled chemical weapons including removal of burster explosive charges,
removal of the liquid chemical agents by drilling or cutting into the payload
reservoir, and separation of metallic parts.
The agent is fed directly into the
first stage of a two stage incinerator under continuous process control to
maintain efficient and complete destruction of the agent. The burster and other parts are passed into a
metal parts furnace where the high explosive and any residual agent is burned
away. The cooled metal parts are removed
from the furnace by a continuous conveyor, cooled and disposed of. The superheated gaseous combustion products
are passed through a scrubber to remove inorganic salts and the exhaust flue
gas is vented through a smoke stack. The
accumulated scrubbed salts, dissolved in condensed water and known as brine,
are disposed of as hazardous waste.
All of the munitions packing
materials, pallets, and associated potentially agent contaminated materials are
then either incinerated, or decontaminated and re-used or disposed of in
hazardous waste landfills. There are
proposals to ship the entirety of this ‘dunnage’ material off site for disposal
as hazardous waste in landfills.
At numerous points along the pathway
of storage, handling and processing of the chemical weapons environmental air
samples are continuously collected to ensure that no chemical agents above
various toxic threshold levels are released.
If one of these monitoring systems detects
agent above a certain threshold, immediate corrective actions up to and
including halting the destruction process are initiated, depending on the
seriousness and location of the agent detection.
The incineration technique has come
under considerable scrutiny from governmental regulatory agencies and private
environmental protection advocacy groups.
The reasons for this scrutiny have to do with a large number of process
failures that have at times resulted in the release of chemical warfare agent
in hazardous quantities.
In addition, like all large
government projects, there have been numerous documented instances of waste,
fraud and abuse by the various involved organizations and individuals.
Critics of incineration cite the
release of chemical agents and toxic combustion products as their reasons for
demanding that the incineration technique be abandoned in favor of safer
technologies.
There are two currently open sites
that use or plan to use second line alternative strategy for agent
destruction. This is the ‘hydrolysis’
method. Hydrolysis makes use of
concentrated sodium hydroxide solutions (lye) and high temperatures to destroy
the agent by chemically breaking it down into less toxic pieces. Hydrolysis was used at Aberdeen Proving
Ground in Maryland;
this site has finished destroying the chemical weapons and is closed.
The major problem with hydrolysis
is that the hydrolysis reaction can reverse under certain conditions resulting
in the re-formation of the original agent.
The high basicity (high pH) of the sodium hydroxide solution is
responsible for causing the chemical degradation that breaks down agent
molecules into smaller less toxic products.
If the basicity (pH) of the solution is lowered by the addition of
acidic materials or by the absorption of carbon dioxide (a greenhouse gas,
present in exhaled air), the chemical reactions that broke up the agent can
reverse, producing the agent and related molecules that have toxicity similar
to that of the original material.
In use the hydrolysis method is
used to break down the agent, the toxic soup of chemicals including the
degraded agent and the highly caustic sodium hydroxide solution, are then
pumped into special tanks that are loaded onto trucks and shipped from the
Newport Chemical Depot in Indiana to Port Arthur Texas
for incineration.
The problems with this strategy are
several. First if the tank truck were to
have an accident causing a spill of the contents of the tank, the enclosed
material would come into contact with the environment. Typically, the pH of the soil is relatively
acidic compared to concentrated sodium hydroxide solution, thus hydrolysate
would be at least partially neutralized by contact with soil. This neutralization, would as described
above, allow the hydrolysis reaction to reverse to a certain degree, resulting
in the re-formation of some of the original nerve agent and closely related
toxic products.
Thus it is possible that in a
massive spill that a significant and toxic concentration of nerve agent could
be formed, exposing emergency crews and the local population. Emergency response crew protocols call for
the containment, neutralization and clean up of any chemical spill. In the case of nerve agent hydrolysate the
standard neutralization procedure would immediately cause the re-formation of a
significant amount of highly toxic nerve agent and similar materials. The trucks transporting hydrolysate are
specially monitored during transit and it is likely that the emergency response
crews along the route would be instructed in special procedures in the event of
a spill, but theoretically the possibility exists of agent release into the
environment.
The second major problem with the
hydrolysis technique is that the Army is not sure how much agent remains in the
product after processing. This is
because the hydrolysis breaks down the agent into several less toxic pieces,
and some of these resulting pieces are not very soluble in water. As a result the hydrolysate contains an oily,
water insoluble layer, a water layer wherein is most of the sodium hydroxide,
and a heavy black sediment that is derived from things such as the
lacquer/corrosion resistant lining of the munitions, paint, sealants,
lubricants and etc. that come off of
the munitions during processing.
From the standpoint of analytical
chemistry, this toxic mixture is extremely challenging. Each of the phases, oily, watery and solid,
must be analyzed for the presence of agent to ensure that the overall content
of non-neutralized agent is less than 20 parts per billion (ppb).
The problem comes in that only the
caustic water layer has been analyzed.
The oily and solid phases are too technically challenging to be easily
analyzed using the tools and techniques available.
In the alternative, the Army has
also sampled the air in containers of hydrolysate, the ‘headspace’, for the
presence of agent vapor. The difficulty
here is that the basic water solution and oily solution will have a very high
affinity for the agent due to its physico-chemical nature and thus the
headspace will likely contain very little agent relative to the concentrations
present in the two liquid phases of the product.
The Army has insisted on several
occasions that the concentration of agent in the hydrolysate is less that 20
ppb, but it has been contradicted in this assertion by one of its own experts
who has admitted in sworn testimony given during a recent court case brought by
a coalition of environmental groups to halt the shipments of hydrolysate that
the levels of agent in the mixed solution are above 20 ppb.
Finally, and possibly most
importantly, are the problems with the final incineration process. In practice, the tanks containing hydrolysate
are delivered to the incinerator site by the trucks, the tanks are then stored
until such time as they are moved to a manifold of pipes connected to the inlet
apparatus of the incinerator and connected to the plumbing feeding waste
liquids into the furnace. The contents
of the tanks are then pumped out of the transport tanks, mixed with other
liquid wastes and fed into the incinerator.
These procedures are accepted practice for hazardous wastes of this
type.
The problem is that at no point
after the departure of the transport truck from the Newport Chemical Depot is
any effort made to monitor for the presence of agent. The agent content of the tanks is measured
before departure, with the limitations as described above, and sent on its way
to Texas.
Given the possibility discussed
above for neutralization of the agent at any of the many points in its journey
to destruction this is at best foolhardy.
First, no one knows what happens when the tank contents are allowed to
sit around waiting for incineration.
Since there is no monitoring, there would be no chance to catch and stop
small leaks of hydrolysate from the tanks.
Second, the hydrolysate is exposed to other chemicals on its way through
the plumbing into the incinerator.
This is done to maintain the high
temperature of the incinerator by balancing the percentages of burnable (fuels
such as hydrocarbon wastes) and non-burnable (water, sodium hydroxide and other
salts in the hydrolysate) materials going into the incinerator such that a
state of stable and predictable operation is maintained.
At high temperatures, chemical
reactions can happen and none of the chemical reactions possible in this
mixing/incineration process have been rigorously examined and backed up by
direct analytical determinations of product formation. As the waste stream burns, other chemical
reactions take place.
Presumably the majority of these
reactions are oxidative and destructive of toxic materials. Unfortunately most waste incinerators produce
measurable quantities of solid particles as ash.
Typically this ash is highly porous
and is therefore capable of carrying any chemical materials not destroyed by
the incinerator out of the smokestack with deposition in the local vicinity due
to gravity. This gritty soot could conceivably
be carrying un-destroyed toxic chemicals and dropping it onto the heads of the
neighbors of the incinerator.
As was mentioned above, at no point
is the presence of nerve agent checked at any point in the transportation or
incineration process. Thus there is the
possibility that any agent that escaped destruction could find its way into the
environment and into the bodies of local citizens. This practice of ‘see no evil, hear no evil,
speak no evil’ demonstrates an incredible degree of disdain for the neighbors
of these facilities by the government and its contractors. If there were agent escaping, the plant
operators would never know it because they did not value the lives of the
potential victims enough to bother looking!
Monitoring explained
The above sections necessarily lead
to questions about the analytical techniques used to monitor for the presence
of chemical warfare agents. The
analytical monitoring effort practiced in the vicinity of chemical warfare
operations facilities makes use of two primary techniques that utilize similar
technologies. These techniques are
called Depot Area Air Monitoring System or DAAMS and the Automated Chemical
Agent Monitoring System or ACAMS. There
is a third technique called Mini-CAMS or MINIature Chemical Agent Monitoring
System. DAAMS, ACAMS and MINI-CAMS all make use of some form of sorbent tube
and for purposes of this discussion are identical and thus will not be
discussed separately. These techniques
monitor for agent vapor in air. There
are additional testing methods used for the detection of liquid chemical agents
but they are not the focus of this analysis and thus will not be discussed.
These techniques make use of
devices called sampling tubes. The
sampling tubes are small glass tubes filled with special resins that absorb
agent molecules from the air. These
tubes are placed on sampling stations at various points in and around the areas
where chemical weapons are handled. Air
is drawn through the tubes to allow the contained resin to capture agent
vapor.
Depending on the type of monitoring
being done, the tubes are exposed to ambient air for periods of up to 12
hours.
Then the tubes are collected and
returned to the laboratory for analysis by one of the methods described in this
section.
Any tubes that come up with levels of
agent above certain defined threshold levels are double checked against another
tube collected simultaneously at the same location. If both tubes are positive then corrective
action is initiated. If either of the
tubes is below the cut-off level, the detection is deemed false or spurious and
disregarded.
Given the observed variability described in the report, this
criterion of requiring two tubes to register above threshold virtually
guarantees that any release, even if above the threshold, will be disregarded.
Gas chromatography
These techniques make use of
analytical instrumentation called a gas chromatograph. A gas chromatograph is an instrument that
separates molecules based in part on their boiling point and in part how much
the ‘like’ to stick to a ‘stationary phase’.
Chromatographic methods make use of, typically, two phases. These are called the stationary phase and the
mobile phase. The mobile phase moves
over and past the stationary phase.
A sample to be analyzed and
separated is introduced into the mobile phase, which in this case is a gas,
typically helium. The molecules in the
sample in the mobile phase are pushed by gas pressure through a tube called the
‘column’ which has a high pressure source of helium at one end and is at lower
pressure at the other end, causing the gas to flow from the beginning to the
end of the tube (column).
Through clever arrangements of
plumbing it is possible to introduce samples to be separated and analyzed into
this flowing gas at the beginning of the column.
The region of the instrument that
holds the beginning of the column is called the injector. The injector is electrically heated to a
temperature above the boiling point of any of the components of the sample, so
that the sample evaporates into the helium mobile phase.
The evaporated sample molecules are
then swept into and down the length of the column by the flowing helium
gas.
The column is kept in another
region of the instrument in a specially designed oven that can be adjusted in
temperature in a very controlled and defined way.
The column is lined with molecules
that are ‘sticky’ to the sample molecules.
This stickiness is derived from the principle that like dissolves like, i.e. greasy things dissolve greasy
things and non-greasy things dissolve non-greasy things. Obviously non-greasy things do not ‘like’ to
dissolve in greasy things and conversely.
In the technique used for
monitoring chemical warfare agents the column is lined with a semi-liquid film
of greasy material. The molecules of
nerve agent are, because of their chemical composition, somewhat greasy but are
also in a way non greasy.
The important fact is that the
molecules of interest do not have the same degree of greasiness, and thus are
more or less likely to spend their time stuck to the stationary phase.
So, as the sample enters the
column, some of the entrained sample molecules stick to the greasy column
lining. The oven in which the column
resides typically starts out at a relatively low temperature, say 40 to 60
degrees Celsius (104 to 140 degrees Fahrenheit). At the starting temperature most of the
sample molecules find their way to and stick to the stationary phase lining the
column. Then, under computer control,
the temperature of the column oven is increased in a slow, reproducible
fashion. As the temperature increases,
the molecules stuck to the stationary phase begin to evaporate into the moving
helium mobile phase.
The rate and temperature of
evaporation of each molecule type in the sample somewhat different. These thermal and physical effects cause each
type of molecule present in the sample to spend a certain amount of time stuck
to the stationary phase, and a certain amount of time evaporated and moving in
the mobile phase.
The end result is that the sample
molecules are separated in space and time by merit of their differing physical
properties, i.e. greasiness and boiling point in this case. This causes the sample molecules to come out
of the exit of the column at different times.
At the end of the column is some
type of detector. There are a large
number of detectors used in this type of work that have a variety of different
operating principles. The technical
details are unimportant for our discussion.
All of the detectors produce some kind of an output signal that is
electronically amplified and recorded by a computer.
These data are called
chromatograms. The chromatograms are two
dimensional displays with time on the x (horizontal) axis and signal intensity
on the y (vertical) axis. Thus a
chromatogram typically takes the form of a line proceeding from left to right
along the bottom of a graph on a page which will show peaks, which take the
form of sharp increases in the signal (y axis) intensity.
The peaks correspond to the times
when sample molecules of a given type are exiting together from the end of the
column and are detected by the detector causing a sharp increase in signal
intensity, followed by a sharp decrease in signal intensity, displayed on the
chromatogram as a ‘peak’.
Because of the very accurately controlled
time/temperature programming of the oven temperature increase, the times that
molecules of a given type come out of the column will be, within narrow limits,
the same from one analysis to the next.
Thus if molecule ’X ‘ is present in
five environmental samples at differing concentrations, the resulting
chromatograms will all contain peaks at the same time with intensities that
correspond directly to the quantity of molecule X in each sample. The fact that molecules of X can be counted
on to come out of the column at the same time from one analysis to the next allows
chemists to identify and measure the quantity of X in any sample with
remarkable accuracy, typically with much less that 1% variability being encountered
in replicate analyses of samples having the same concentrations of the analyte
X.
This allows for the quantitative
analysis of samples by making use of standards containing known quantities of
analyte molecules of interest that can be compared to unknown samples and the
ratio of intensities of the peaks can be used to calculate the quantity of
analyte present in an unknown sample.
Thus, by looking for peaks that
come out at the same time as the peaks derived from a standard, and comparing
the intensity of the peaks of the standard solution to those of an unknown
sample, it is possible to determine with good accuracy the quantity of analyte
present in the unknown sample
So, in summary, gas chromatography
can be used to identify (by time) and quantify (by peak intensity) the amount
of any given molecule present in a sample given the availability of known
concentration standards. Thus it should
be clear that it is possible to separate and quantify the presence of chemical
warfare agents in environmental samples.
In use the instruments are set up to
look for peaks due to agents within ‘windows’ or time ranges. Analyte peaks coming out of the instrument
within the boundaries of the windows (this is referred to as ‘having the same
retention time’) are counted as being due to agent and are measured and
quantified.
The purpose of this practice is to
exclude peaks due to environmental and procedural interferences. These extraneous peaks arise, for example,
from hydrocarbons (for instance from vehicle exhaust) that are normally found
in samples of air taken in the vicinity of industrial operations.
The corollary of this is that peaks
that fall outside of the window are ignored.
The current practice at the
chemical weapons holding sites is to only analyze for the agent that is present
in the area of a given monitor, for instance if GB is being handled on a given
day, only GB is monitored for. HD and VX
are treated likewise creating the possibility that an analyst may miss the
presence of agents other than those being tested for on a given day.
Mass spectrometry
The mass spectrometer on the other
hand will take some explaining. A mass
spectrometer is in instrument that separates, analyzes and detects molecules on
the basis of their molecular mass. The
molecular mass of an analyte is determined by the identities and numbers of
elements, such as carbon, hydrogen and nitrogen that are present in its
molecular structure.
The operating principle of the mass
spectrometer used in the preparation of the report can most easily be conceived
by reference to the following analogy.
All of us have at one time or
another swung a mass, such as a ball, attached to a string in a stable circular
orbit. Now extend the experiment by
making the string stretchable, as it would be in the case of a rubber
band. Now imagine that the ball attached
to the rubber band is being caused to swing around your hand at a constant
rate. The ball will adopt a stable
orbit, at a fixed distance from the center of the rotation. Now imagine that the mass of the ball is
suddenly doubled. What happens if the
orbital rate remains the same? The
rubber band will of course stretch due to the additional force exerted on it by
the doubled mass of the ball and the ball will adopt an orbit further from the
axis of rotation.
It is in this way that the ion trap
mass spectrometer described in the report operates. Low mass molecules have smaller radii of
gyration or orbits than do larger mass molecules.
This physical phenomenon allows the
mass spectrometer to be used to separate molecules based on their relative
molecular masses, which is determined by their elemental compositions.
An additional advantage of the mass
spectrometer used is that it allows the user to cause the rotating molecules to
fragment, i.e. break apart into its
components. The fragments are formed
according to relatively complex rules but the end result is that the fragments
are characteristic of the parent molecule, a kind of molecular fingerprint,
allowing one to deduce from the pattern of fragments, and the molecular mass of
the parent the molecular structure of the analyte in question.
Thus the mass spectrometer is an
extremely powerful tool for identification of molecules present in samples, and
the authors of the report make several statements regarding molecular
identities in the text that are important to the conclusions drawn.
Description of the problems with the detection
technologies
Sampling tubes and associated
problems
Due to the high toxicity of the
chemical warfare agents, it is necessary to monitor extremely low
concentrations of the agents in air samples.
Due to the limitations of current
analytical instrumentation, it is necessary to collect agent molecules present
in large volumes of air, and concentrate them to the point that the
instrumentation can ‘see’ the agent molecules.
This concentration technology is at
the center of DAAMS ACAMS and MINI-CAMS techniques. In these techniques, air is drawn through a
specially designed collection tube called a DAAMS, pre-concentrator or sampling
tube. This tube is a hollow glass
cylinder about the diameter of a pencil and four or so inches long. Inside the tube is a packing material that
absorbs molecules out of the air.
Air is sucked through by tube by
applying suction from a vacuum pump to one end of the tube for a certain amount
of time. The flow rate of air through
the tube is carefully calibrated such that about 1 liter per minute of air
flows through the tube. Any agent
molecules present in the incoming air are captured by the packing material in
the tube.
This packing material behaves in
the same was as does the stationary phase discussed above in the gas
chromatography section. The agent
molecules ‘like’ to stick more to the packing than they ‘like’ to be in air and
thus build up over time in the packing material as more and more air is sucked
through the tube, thus concentrating the molecules for later analysis.
There are mainly two types of DAAMS
tube packing materials used in chemical warfare agent monitoring, Chromosorb
106 is used for nerve agents and Tenax TA is used for mustard. Tenax GR is also used but is very similar to
Tenax TA. In some tubes several packing
materials are combined to produce tubes capable of capturing both classes of
agents.
In use the tubes are placed on the
sampling stations for certain time periods that vary with the type of
monitoring being done, air is sucked through them and any agent present in the
air is absorbed by the packing material present in the tubes. The tubes are collected periodically and
returned to the monitoring laboratory for analysis.
In the laboratory the tubes are
connected by fittings to smaller diameter tubes of the same basic composition
and design as the collection tubes. These
smaller tubes are known as transfer tubes, because they are used to transfer
trapped agent molecules from the sampling tubes to the analytical
instrumentation.
In use, the collection tube is
connected to a transfer tube, the collection tube is placed in an electrically
heated metal block and connected to a helium supply line. As the collection tube warms up, the agent
molecules trapped in the packing evaporate and are carried by the helium gas
flowing through the tube into the transfer tube. The transfer tube is at room temperature, or
fairly close to it considering that it has hot helium passing through it, where
the agent molecules again encounter packing material identical to that
contained in the collection tube. Thus
the agent molecules are captured by the packing of the transfer tube. After a couple of minutes, the transfer tube
is disconnected from the transfer apparatus and is ready for analysis.
The transfer tube is then connected
to another helium supply line and the tube is placed into the injector of the
gas chromatograph described above. The
heat of the injector causes the agent molecules to again evaporate into the
helium carrier gas and thence to flow into the column of the gas chromatograph
as described above.
This sample preparation routine is
used because the transfer tubes are too small to pull an adequate quantity of
air through in a reasonable time, and the collection tubes are too big to fit
in to the injector of the gas chromatograph.
Operationally, the tubes are identical in function, the only difference
being size and point of application in the analytical process.
The most serious problem identified
in the report is because of deficiencies in these tubes. Some of the tubes capture agent molecules
better than do others, with the reported tube to tube variability being
somewhat greater than 103 (pronounced ‘ten to the third’), or 1000-fold.
This degree of variability in
capture efficiency means that the technique is unable to differentiate between
a toxic (IDLH or immediately dangerous to life and health) level and a level
that chemical weapons workers are permitted to breathe (safe?) in an 8 hour
work shift (the TWA8 level).
The instrumentation is calibrated
using certified standards of agent dissolved in organic solvent, isopropanol
(found in rubbing alcohol) for the nerve agents and hexane (similar to lighter
fluid) for mustard. I will expand later
on the problems caused in the report by these solvents.
As an aside, the instrumentation used
for the acquisition of the data discussed in the report had two detectors, a
pulsed flame photometric detector and a mass spectrometer. The authors state that the pulsed flame
photometric detector was disconnected fairly early in the experiments and will
not be discussed further here. The
interested reader is referred to the text of the report for the rationalization
of this decision.
Analysis of
interferences
The authors
also made a small study of interferences present on the DAAMS tubes. A set of tubes was obtained from the TOCDF
site in Utah. These tubes were taken from those in use at
the time for agent monitoring and were thus representative of the tubes used to
protect the public from agent releases.
The authors show that the tubes were severely degraded, brown in color
due to oxidation and unusable for capturing agent at levels many times higher
than the level at which agent exposures are considered dangerous. As these tubes were pulled from the pool of
tubes in active use for monitoring, this observation indicates that even if
there were a massive agent release, the monitoring equipment would not detect
the agent, even at levels that could kill unprotected people within
minutes.
The authors also conducted
experiments to determine the source of the interferences that were observed
coming off of the tubes. The authors
found that the interferences did not come from contaminants present in the air,
such as vehicle exhaust. What was found
was that the interferences were derived from the tubes themselves. The authors proposed and generated data
supporting the thesis that tubes were breaking down due to the conditions under
which they were conditioned, i.e. broken in prior to use, as well as the
heating cycles employed when the tubes are analyzed after sample collection.
The problem here is twofold, first
the interferences obscure the presence of agent peaks, and second the
interferences indicate that the tubes are degraded, incapable of picking up
agent, and are therefore useless for agent monitoring.
It is not stated how long that the
tubes in question have been in use, leaving open the possibility that the
public has been repeatedly exposed to toxic levels of agent since the very
beginning of these programs.
The analysis of VX
and the problem of transesterification
Finally, at least for the technical
section, we need to examine the analysis of the nerve agent VX. Using the techniques described above, VX is a
very difficult to analyze molecule. It
has a high boiling point and has lots of atoms that cause it to be what
chemists call ‘polar’, meaning that the molecule is not very greasy. It is also, relative to other agents, fairly
large, having a higher molecular mass.
These factors combine to make VX a difficult case for analysis by gas
chromatography (GC) or gas chromatography mass spectrometry (GCMS).
To overcome these problems, the Army
has developed a technique that converts the VX molecules present in air into a
form that is more easily analyzed using GC or GCMS.
The technique makes use of a small
filter impregnated with silver fluoride that is attached to the inlet end of a
sampling tube during sample collection.
The silver fluoride on the filter pad causes a chemical reaction in
which the VX molecules that are drawn through the filter pad are converted to a
chemical form that is much easier to analyze using GC or GCMS. The product molecule is very similar to GB,
except that instead of having an isopropyl group, it has an ethyl group.
The problem with this technique
arises because, as mentioned above, the standards used to calibrate the
instrumentation are dissolved in isopropanol.
The standard solution is applied directly to the inlet surface of the
silver fluoride impregnated filter pad.
The report details experiments that show that when VX standard in
isopropanol is applied to a conversion pad, some of the resulting GB analog of
VX, denoted VX(G), is actually converted to GB.
This observation is extremely
important because as described above, the analytical instrumentation is
typically only set up to monitor for one agent at a time, peaks falling outside
of a pre-set time range or window are ignored.
Thus, if some of the VX is being
converted to GB and some is converted to the desired product VX(G), the portion
that is converted to GB is ignored and not counted! The distortion of the instrument response
causes the VX analysis to be incorrect.
The chemical reaction that occurs
is called transesterification. As
mentioned above, VX(G) has an ethyl group, the isopropanol can chemically react
with the VX(G) and remove the ethyl group substituting an isopropyl group,
converting the VX(G) to GB, which is not counted.
The real importance of this
observation though is not so much that some GB is formed when the standards are
analyzed, it is that water can also participate in this type of reaction. Water vapor is present in the atmosphere at
all times, and isopropanol is pretty rare thus water will dominate reactions
with airborne VX. The product of the transesterification
reaction of VX(G) with water is fluoromethylphosphonic acid, a very high
boiling point material that is not the object of any of the analyses.
Thus at least two ‘side reactions’
are possible, one that produces GB, the other producing fluoromethylphosphonic
acid that the instrument can not even see.
The danger here is that the unknown air sample has a significant amount
of water vapor in it, which would lead to potentially significant undercounting
of the quantity of VX present in a given air sample, and this underestimation
would vary dependent on factors such as relative humidity and ambient
temperature.
This finding leaves open a huge
question, i.e. how much of the VX
floating around in the air is being converted to fluoromethylphosphonic acid
and is lost to analysis? No one has ever
done these experiments and published the results. This loss could be leading to extremely
significant undercounting of the VX present in the air around these sites,
resulting in the exposure of every one downwind for hundreds of miles due to
the chemical stability of the VX molecule in the environment.
Summary of results of
analytical methods findings
The above
descriptions, taken together make clear the following problems:
1) The DAAMS tubes have a degree of
variability in agent retention that precludes their effective use for
determination of agent levels.
2) The DAAMS tubes are very sensitive to
conditioning and improper use or conditioning can irreparably damage the
packing material making the tubes useless for agent monitoring.
3) The silver fluoride conversion pads
used for the detection of VX can cause the level of VX present to be
significantly underestimated due to the presence of at least two competing side
reactions that produce forms of VX that are not detected by the instrumentation.
4) The DAAMS tubes in routine use are all
significantly degraded and that agent spiked onto the tubes was not detectable
at levels many times the danger level.
5) The methods used in handling the DAAMS
tubes damage their ability to capture agent from the air and there seems to be
no procedure in place to retire tubes that are at the end of their useful
lifetime.
Sulfur mustard and
monitoring
The authors
make clear that the monitoring of sulfur mustard was relatively straightforward
using the DAAMS technology. This is
likely due to the physical and chemical properties of sulfur mustard. Mustard is easily distinguished from
background interferences and it is well retained by the DAAMS tubes.
Unfortunately the degradation of
the tubes negatively effects mustard in the same manner as was observed for the
nerve agents. It is thus likely that the
tubes used to monitor for mustard releases are also so damaged by use as to be
completely useless.
In addition it has come to light
that many of the mustard preparations are contaminated with significant
quantities of mercury.
Mercury is an intensely toxic metal
that evaporates easily at room temperature and that is not destroyed by the
incineration process.
Mercury is a potent neurotoxin, in
fact the expression ‘mad as a hatter’ arises from the dementia caused in 19th
century hat makers exposed to mercury that was at the time used in the making
of felt for hats.
In the 1960’s there was an
environmental disaster caused by mercury containing wastes that were dumped
into Minimata Bay
in Japan.
Enormous damage was suffered by the
people exposed to the released mercury.
The environment was extensively contaminated and many people suffered
from unnecessary morbidity and mortality.
The industrial polluters released mercury into the environment because
it would have cost more to prevent the releases. The local population made its living by
fishing. The fish took up the mercury
and the people ate the fish.
The toxicity of mercury has been
known for many years, and there is no excuse for willfully releasing it into
the environment.
The incinerators used for burning
chemical weapons can be fitted with scrubbers to remove the mercury from the
exhaust gasses, but the removal is not complete. Thus anyone down wind will suffer
exposure. It is extremely irresponsible
of the government and its contractors to dispose of mercury contaminated
mustard by incineration.
Everyone exposed will be poisoned,
and of course the government will take steps to protect itself and its
contractors from any liability to those who are injured.
Health effects of nerve agent exposure
Everyone
acknowledges that the nerve agents are acutely dangerous compounds. What is less clear are the effects of
exposure to low levels of these materials.
As doing experiments of this type on humans is no longer considered
ethical, we must draw inferences from studies done on animals or
epidemiological studies done on people exposed to similar materials, such as
pesticides, in the course of their jobs.
An ever increasing number of
reports are being published that link exposure to chemicals of these types to a
broad range of diseases. Occupational
and accidental exposures constitute the majority of cases, but there have also
been studies of soldiers exposed in action.
Sulfur mustard is acknowledged as a
carcinogenic material. It is known to
react with and damage DNA, inducing irreversible mutations to the genetic code
of the affected cells. It is also known to have other longer range effects. Studies done of soldiers exposed to mustard
during the Iran-Iraq war of the 1980’s have shown many long term effects,
including elevated incidence of cancer, immune system problems, and a number of
neurological problems such as intractable pain syndromes.
The nerve
agents GB and VX are members of the organophosphate family that inhibit the
activity of acetylcholinesterase, a critical enzyme involved in nerve signal
transmission.
As described above, these agents
originated in pesticide research conducted during the inter-war years by German
scientists. VX was developed after the
war by British scientists.
Interestingly, the scientific data and ‘formula’ for VX were transferred
to the United States by the
British government in exchange for nuclear weapons secrets developed during the
war by the United States. The Soviets developed their own chemical
weapons program with some differences in the agents that were ultimately chosen
to be developed into weapons.
Originally
it was thought that the organophosphates exerted their effects exclusively
through their inhibition of acetylcholinesterase. Epidemiological studies of pesticide workers
have shown though that these agents have a broad range of negative effects on
human health. In fact the United States
Environmental Protection Agency has been considering a ban on this class of
compounds. Among the health effects
noted are increases in non-Hodgkins lymphoma and brain tumors in the children
of exposed parents, asthma and other immunological diseases have also been
associated with exposure.
There is considerable controversy
surrounding the issue of Gulf War Syndrome.
It is a group of disparate symptoms associated with service in the first
Gulf War. It has so far remained
mysterious despite intensive study by many researchers. The causes are not clear, and the symptoms
are not uniform. But it is clear that
those affected are sick, the questions are how it happened and why.
Adding to the controversy, the U.S. government
at first asserted that there was no agent exposure to coalition troops during
the war. Subsequent revelations have
shown however that many troops were exposed to low levels of airborne agents
during their service, most notably from the infamous Kamisiyah incident, where
coalition troops used explosives to destroy a cache of Iraqi chemical
munitions, in the process generating a huge cloud of agent that was swept by
the wind over coalition positions extending many miles down wind from the
explosion and exposing a long list of military units.
Nonetheless, many of the symptoms
cited by the ailing soldiers are the same as those observed in those exposed to
high concentrations of organophosphate pesticides, mostly farm workers,
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