Nerve Agents, Nerve Agents, Tabun and VX Tabun and VX gas: Chemical gas: Chemical

Weapons of Mass Weapons of Mass DestructionDestructionJoe

Lach

VX GasTabun Gas

Other Common Nerve AgentsOther Common Nerve Agents

Sarin

Cyclosarin

CS (Tear Gas)

Dimethylamidoethoxyphosphotyl Dimethylamidoethoxyphosphotyl

cyanidecyanide Least Deadly, but most volatile:

Volatility: v.p. 0.07 mmHg at 25°C

Solubility: Water, but rapidly hydrolyzed

SS-(2-Diisopropylaminoethyl) -(2-Diisopropylaminoethyl) OO-ethyl -ethyl methylphosphonothiolatemethylphosphonothiolate

Most Deadly, but least volatile:

Volatility: v.p. 7.0 × 10-4 mmHg

Solubility: Water: 30 g/l

TabunTabun

VXVX

Important Similarities needed Understand the Mechanism of Nerve Agents

Representation of Representation of Acetylcholine in Acetylcholine in the binding site of the binding site of a receptora receptor

Activity of Activity of Acetylcholine Acetylcholine Receptor Receptor following Bindingfollowing Binding

How do Nerve Agents How do Nerve Agents Work?Work?

Why don’t the receptors stay on Why don’t the receptors stay on all the time?all the time?

Acetylcholine Esterase

Proper Function of AChE

What are the Nerve Agents What are the Nerve Agents Doing?Doing?Example using Diisopropyl

phosphofluoridate (DIPF)

Acetylcholine Esterase constitutively binds the Nerve Agent’s phosphate and is then rendered inactive

Pathway of Pathway of PoisoningPoisoning

1. Contact with VX

2. Headache and Drowsiness

3. Nausea and Diarrhea

4. Altered BP and Breathing

5. Loss of Consciousness

6. Convulsions

7. Paralysis

8. Death

1. Contact with Tabun

2. Headache and Drowsiness

3. Nausea and Diarrhea

4. Altered BP and Breathing

5. Loss of Consciousness

6. Convulsions

7. Paralysis

8. Death

After Contact with a Lethal Dose (LD)

=

What’s the difference?...

DifferencDifferenceses

Concentration in Air

Tabun LD 500 ppb

VX LD 20-30 ppb

Carbon Dioxide 375 ppm

Methane 1750 ppb

Nitrous Oxide 300 ppb

Moderate Dose Time for full effect

Tabun 6-12 hrs

VX 30min-2hrs

Lethal Dose is determined by measuring the quantity needed to kill half the rats and then multiplying by an average body mass index to determine dangerous levels for humans.

Lethal Dose Time till death

Tabun 5-10min

VX 15sec-1min

TreatmentTreatment

Atropine Sulfate – Acetylcholine Blocker, blocks other acetylcholine-like compounds by binding the Acetylcholine receptor in such a way as to NOT activate the Na channel.

Any Current Threat?

Newport – Located in Indiana only stores VX gas reserves and these are kept in steel drums under 24 hours protection. As of 9/11 most of this supply has supposedly been scheduled for destruction.

http://www.cma.army.mil/newport.aspx

http://www.defenselink.mil/releases/1996/b012496_bt024-96.htmlwww.unc.edu/news/archives/apr03/hce040703.htmlwww.cmbi.kun.nl/samsam/visualisatie/4.gifwww.nimr.mrc.ac.uk/physbiochem/hulme/fig/http://www.cdc.gov/page.dohttp://cdiac.ornl.gov/pns/current_ghg.htmlGangolli, S. (2005). Dictionary of Substances and Their Effects (DOSE, 3rd Electronic Edition).

Royal Society of Chemistry. Access through http://www.knovel.com/knovel2/Toc.jsp?

BookID=527&VerticalID=0Pohanish, R.P. (2002). Sittig's Handbook of Toxic and Hazardous Chemicals and Carcinogens

(4th Edition). William Andrew Publishing/Noyes. Access through

http://www.knovel.com/knovel2/Toc.jsp?BookID=421&VerticalID=0Arie Ordentlich, Dov Barak, Gali Sod-Moriah, Dana Kaplan, Dana Mizrahi, Yoffi Segall,

Chanoch Kronman, Yishai Karton, Arie Lazar,. (2004) Stereoselectivity toward VX

Is Determined by Interactions with Residues of the Acyl Pocket as Well as of the

Peripheral Anionic Site of AChE. Biochemistry, 43 (35), 11255 -11265Ramesh C. Gupta, Gary T. Patterson and Wolf-D. Dettbarn. (1987). Acute tabun toxicity;

biochemical and histochemical consequences in brain and skeletal muscles of rat.

Toxicology. Vol. 46-3, 329-341.J. Heath, Andrew MD PhD. (2002). Antidotes for Poisoning by Organophosporus Pesticides.

International Programme on Chemical Safety Evaluation.

Works Cited

pics

Questions?Questions?