Nerve gas
or
nerve agent
is the name of a family of chemical
poisons
. Usually people call them
nerve agents
(they are not always
gases
). They work by changing the way the
nerves
work in the human body. They stop messages (signals) from the
brain
from getting sent to the
muscles
and
organs
.
Nerve agents are
organic chemicals
that have
phosphorus
in them (
organophosphates
). Many organophosphates are
pesticides
, and have the same effects as nerve agents if people are
exposed
to them. However, these pesticides are not used against people as weapons like nerve agents are.
[1]
Since they are
chemical weapons
, nerve agents are classified as
weapons of mass destruction
by the
United Nations
according to
UN Resolution 687
. Since 1993, making or
stockpiling
them has been against
international law
.
[2]
Nerve agents have long-lasting effects. People who survive nerve agent poisoning almost always have
chronic
damage to the brain and nerves. This damage can also cause
mental health
problems.
[3]
Nerve agents work by blocking communication between the brain and the body. Usually, a
neurotransmitter
(a chemical messenger) called
acetylcholine
gives the signal for the muscles to tighten up. It also keeps them from relaxing. However, when it is time for the muscles to relax, an
enzyme
called
acetylcholinesterase
destroys acetylcholine, and another neurotransmitter tells the muscles to relax.
[4]
Nerve agents work by blocking acetyl-cholinesterase. Too much acetylcholine builds up, because it is not getting destroyed by acetylcholinesterase. The muscles keep getting more and more signals to tighten up. Basically, the brain loses control over the body's muscles. It cannot make the muscles relax. This leads to many of the unique
signs and symptoms
of nerve agent poisoning.
[5]
Acetylcholine also signals the
parasympathetic nervous system
(PNS) to kick in. Usually, the PNS balances out with the
sympathetic nervous system
to maintain
homeostasis
. However, when there is too much acetylcholine, the two systems cannot balance, and the sympathetic nervous system does not work correctly.
[5]
Nerve agent poisoning causes a very unique group of signs and symptoms. Some medical providers use the
acronym
"SLUDGE" to remember them:
[6]
[7]
- S
alivation: The
salivary glands
make a very large amount of
saliva
(spit); the person will drool a lot
- L
acrimation:
Tears
will run out of the person's eyes
- U
rination
: As the brain loses control over the body's muscles, the person will involuntarily urinate
- D
efecation
: For the same reason, the person will also involuntarily defecate
- G
astric upset
: The person will have an upset
stomach
- E
mesis
: The person will vomit
Some medical professionals use a different version of this acronym: "SLUDGE and the Killer B's." The Killer B's are three life-threatening
symptoms
:
[7]
- Bradycardia
: Slow
heart rate
(caused by over-activity in the parasympathetic nervous system)
- Bronchoconstriction: The
bronchi
(tubes to the lungs) get narrower, as the muscles around the airways tighten up
- Bronchorrhea: Making more than 100
mL
of
mucus
per day. This can build up in the
lungs
or make the lungs be unable to inflate normally
[8]
As the person gets worse, they will have
muscle twitches
, then start having
seizures
and go into
status epilepticus
. People can die because their brain cannot control their
breathing
muscles, and they stop breathing.
These nerve gases are called "G series" because they were first created by German
scientists
. They were all discovered and made before or during
World War II
.
[9]
Nobody agrees on why these nerve gases are called "V series." Different people say the V stands for "Victory," "Venomous" (poisonous), or "Viscous" (thick liquid).
[9]
There have been two major
international laws
that relate to nerve agents:
- Hague Convention of 1899
: This was the first agreement that made it illegal to use
toxic
gas as a weapon (in section IV,2.)
[10]
- Geneva Protocol
of 1925: This agreement was signed on June 17, 1925, and took effect on February 8, 1928. It permanently bans the use of all forms of
chemical
and
biological warfare
.
[11]
The agreement was signed after
World War I
, where
mustard gas
and
other chemical weapons were used
. People were afraid that chemical and biological warfare could have terrible effects in any future war. The protocol was extended by the
Biological Weapons Convention
(1972) and the
Chemical Weapons Convention
(1993).
- ↑
"Facts about Nerve Agents"
.
Emergency Preparedness and Response
. New York State Department of Health. July 23, 2014
. Retrieved
February 9,
2016
.
- ↑
"Reference: C.N.492.2015.TREATIES-XXVI.3 (Depositary Notification)"
(PDF)
.
Secretary-General of the United Nations
. September 18, 2015
. Retrieved
February 9,
2015
.
- ↑
Sidell FR 1974 (1974).
"Soman and sarin: clinical manifestations and treatment of accidental poisoning by organophosphates"
.
Clinical Toxicology
.
7
(1): 1?17.
doi
:
10.3109/15563657408987971
.
PMID
4838227
.
{{
cite journal
}}
: CS1 maint: numeric names: authors list (
link
)
- ↑
Mistovich, Joseph J.; Karren, Keith J.; Hafen, Brent (July 18, 2013).
Prehospital Emergency Care
(10th ed.). Prentice Hall.
ISBN
978-0133369137
.
- ↑
5.0
5.1
"Nerve Agents".
Medical Aspects of Chemical and Biological Warfare
. Washington, D.C.: Office of the Surgeon General at TMM Publications. 1997. pp. 129?179. Archived from
the original
on 2017-03-18
. Retrieved
2016-02-10
.
- ↑
Wagner, Mary J.; Promes, Susan B. (January 1, 2007).
Last Minute Emergency Medicine: A Concise Review for the Specialty Boards
. McGraw Hill Professional. p.
12
.
ISBN
978-0-07-150975-6
.
- ↑
7.0
7.1
"EMS Subspecialty Certification Review Course: Organophosphates"
(PDF)
.
UTSW.ws
. University of Texas Southwestern Medical Center. September 5, 2013
. Retrieved
February 9,
2016
.
[
permanent dead link
]
- ↑
Abbott, Parker, Mark S.; Rosado de Christenson, Melissa L.; Abbott, Gerald F. (2005).
Teaching Atlas of Chest Imaging
. New York: Thieme.
ISBN
978-1588902306
.
{{
cite book
}}
: CS1 maint: multiple names: authors list (
link
)
- ↑
9.0
9.1
9.2
"Nerve Agents"
.
emergency.cdc.gov
. United States Centers for Disease Control and Prevention (CDC). April 19, 2013
. Retrieved
December 26,
2015
.
- ↑
"Laws of War: Declaration on the Use of Projectiles the Object of Which is the Diffusion of Asphyxiating or Deleterious Gases; July 29, 1899"
.
The Avalon Project: Documents in Law, History, and Diplomacy
. Yale Law School Lillian Goldman Law Library
. Retrieved
February 9,
2016
.
- ↑
"1925 Geneva Protocol"
.
United Nations Office for Disarmament Affairs
. United Natios
. Retrieved
February 9,
2016
.