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Chemical Datasheet

PHOSPHONOTHIOIC ACID, METHYL-, S-(2-(BIS(1-METHYLETHYL)AMINO)ETHYL) O-ETHYL ESTER

6.1 - Poison

Chemical Identifiers

CAS Number UN/NA Number DOT Hazard Label USCG CHRIS Code
  • 50782-69-9
  • 2810
  • Poison
none
NIOSH Pocket Guide International Chem Safety Card
none none
NFPA 704
data unavailable
General Description
Odorless liquid, with an amber color. Used as a quick-acting military chemical nerve agent.

Hazards

Reactivity Alerts
none
Air & Water Reactions
No rapid reaction with air. No rapid reaction with water.
Fire Hazard
Highly toxic nitrogen oxides and sulfur oxides. Avoid extreme heat. (EPA, 1998)
Health Hazard
Cholinesterase inhibitor. Lowest toxic oral dose (TDLO) to humans is 4 mg/kg; lowest lethal skin dose to humans (LDLO) is 86 mg/kg. Death within 15 minutes after fatal dose is absorbed. (EPA, 1998)
Reactivity Profile
Organophosphates are susceptible to formation of highly toxic and flammable phosphine gas in the presence of strong reducing agents such as hydrides. Partial oxidation by oxidizing agents may result in the release of toxic phosphorus oxides.
Belongs to the Following Reactive Group(s)
Potentially Incompatible Absorbents

Use caution: Liquids with this reactive group classification have been known to react with the absorbent listed below.

Response Recommendations

Isolation and Evacuation
Excerpt from ERG Guide 153 [Substances - Toxic and/or Corrosive (Combustible)]:

As an immediate precautionary measure, isolate spill or leak area in all directions for at least 50 meters (150 feet) for liquids and at least 25 meters (75 feet) for solids.

SPILL: If this material is being used as a weapon, see ERG Table 1 - Initial Isolation and Protective Action Distances on the UN/NA 2810 datasheet. Otherwise increase, in the downwind direction, as necessary, the isolation distance shown above.

FIRE: If tank, rail car or tank truck is involved in a fire, ISOLATE for 800 meters (1/2 mile) in all directions; also, consider initial evacuation for 800 meters (1/2 mile) in all directions. (ERG, 2016)
Firefighting
Use protective clothing and respiratory protection. (EPA, 1998)
Non-Fire Response
Decontaminants include bleach slurry and hot soapy water. (EPA, 1998)
Protective Clothing
For emergency situations, wear a positive pressure, pressure-demand, full facepiece self-contained breathing apparatus (SCBA) or pressure- demand supplied air respirator with escape SCBA and a fully-encapsulating, chemical resistant suit. (EPA, 1998)
DuPont Tychem® Suit Fabrics
Normalized Breakthrough Times (in Minutes)
Chemical CAS Number State QS QC SL C3 TF TP BR RC TK RF
VX Nerve agent (>95%, 10 g/m² coverage) 50782-69-9 Liquid >480 >480 >480 >480 >480 >480
VX Nerve agent (>95%, 100 g/m² coverage) 50782-69-9 Liquid >480 >480 >480 >480 >480 >480
> indicates greater than.
A blank cell indicates the fabric has not been tested. The fabric may or may not offer barrier.

Special Warnings from DuPont

  1. Serged and bound seams are degraded by some hazardous liquid chemicals, such as strong acids, and should not be worn when these chemicals are present.
  2. CAUTION: This information is based upon technical data that DuPont believes to be reliable. It is subject to revision as additional knowledge and experience are gained. DuPont makes no guarantee of results and assumes no obligation or liability...

(DuPont, 2018)

First Aid
Warning: Immediate decontamination of the smallest drop is essential. Death can occur 15 minutes after a fatal dose is absorbed.

Note: Phosphonothioic acid, methyl-, S-(2-(bis(l-methylethyl) amino)ethyl) O-ethyl ester is an extremely active cholinesterase inhibitor.

Signs and Symptoms of Phosphonothioic acid, methyl-, S-(2-(bis(l methylethyl)amino)ethyl) O-ethyl ester exposure: The first indication of exposure to phosphonothioic acid, methyl-, S-(2-(bis(l-methylethyl) amino) ethyl) O-ethyl ester may be a reaction at the point of contact: localized sweating, muscle twitching, and pinpoint eye pupils. Rhinorrhea (running nose), tightness of the chest with shortness of breath, and dimness of vision may be noted. In more severe exposure, headache, cramps, nausea, vomiting, involuntary defecation and urination, twitching, jerking, staggering, convulsions, drowsiness, coma, and respiratory arrest may be seen.

Emergency Life-Support Procedures: Acute exposure to phosphonothioic acid, methyl-, S-(2-(bis(l methylethyl)amino)ethyl) O-ethyl ester may require decontamination and life support for the victims. Emergency personnel should wear protective clothing appropriate to the type and degree of contamination. Air-purifying or supplied-air respiratory equipment should also be worn, as necessary. Rescue vehicles should carry supplies such as plastic sheeting and disposable plastic bags to assist in preventing spread of contamination.

Inhalation Exposure:
1. Move victims to fresh air. Emergency personnel should avoid self-exposure to phosphonothioic acid, methyl-, S-(2-(bis(l- methylethyl)amino)ethyl) O-ethyl ester.
2. RUSH to a health care facility!
3. Evaluate vital signs including pulse and respiratory rate, and note any trauma. If no pulse is detected, provide CPR. If not breathing, provide artificial respiration. DO NOT perform mouth-to-mouth resuscitation when facial contamination exists. If breathing is labored, administer oxygen or other respiratory support.
4.Obtain authorization and/or further instructions from the local hospital for administration of an antidote or performance of other invasive procedures.

Dermal/Eye Exposure:
1. Remove victims from exposure. Emergency personnel should avoid self-exposure to phosphonothioic acid, methyl-, S-(2- (bis(l-methylethyl)amino)ethyl) O-ethyl ester.
2. RUSH to a health care facility!
3. Evaluate vital signs including pulse and respiratory rate, and note any trauma. If no pulse is detected, provide CPR. If not breathing, provide artificial respiration. DO NOT perform mouth-to-mouth resuscitation when facial contamination exists. If breathing is labored, administer oxygen or other respiratory support.
4. Remove and isolate contaminated clothing as soon as possible.
5. If eye exposure has occurred, eyes must be flushed with lukewarm water for at least 15 minutes.
6. Wash exposed skin areas thoroughly with commercial household bleach and then flush with water. Avoid contacting the eyes or mouth with bleach.
7. Obtain authorization and/or further instructions from the local hospital for administration of an antidote or performance of other invasive procedures.

Ingestion Exposure:
1. Evaluate vital signs including pulse and respiratory rate, and note any trauma. If no pulse is detected, provide CPR. If not breathing, provide artificial respiration. DO NOT perform mouth-to-mouth resuscitation when facial contamination exists. If breathing is labored, administer oxygen or other respiratory support.
2. RUSH to a health care facility!
3. Obtain authorization and/or further instructions from the local hospital for administration of an antidote or performance of other invasive procedures.
4. DO NOT induce vomiting or attempt to neutralize!
5. Activated charcoal may be administered if victims are conscious and alert. Use 15 to 30 g (1/2 to 1 oz) for children, 50 to 100 g (1-3/4 to 3-1/2 oz) for adults, with 125 to 250 mL (1/2 to 1 cup) of water.
6. Promote excretion by administering a saline cathartic or sorbitol to conscious and alert victims. Children require 15 to 30 g (1/2 to 1 oz) of cathartic; 50 to 100 g (1-3/4 to 3-1/2 oz) is recommended for adults. (EPA, 1998)

Physical Properties

Chemical Formula:
  • C11H26NO2PS
Flash Point: 318.2 ° F (EPA, 1998)
Lower Explosive Limit (LEL): data unavailable
Upper Explosive Limit (UEL): data unavailable
Autoignition Temperature: data unavailable
Melting Point: Freezing point below -60° F (EPA, 1998)
Vapor Pressure: 0.0007 mm Hg at 77 ° F (EPA, 1998)
Vapor Density (Relative to Air): 9.2 (EPA, 1998)
Specific Gravity: 1.0083 at 77 ° F (EPA, 1998)
Boiling Point: 568 ° F at 760 mm Hg decomposes (EPA, 1998)
Molecular Weight: 267.37 (EPA, 1998)
Water Solubility: data unavailable
Ionization Potential: data unavailable
IDLH: data unavailable

AEGLs (Acute Exposure Guideline Levels)

Final AEGLs for Agent VX (50782-69-9)
Exposure Period AEGL-1 AEGL-2 AEGL-3
10 minutes 5.2e-05 ppm 0.00065 ppm 0.0027 ppm
30 minutes 3e-05 ppm 0.00038 ppm 0.0014 ppm
60 minutes 1.6e-05 ppm 0.00027 ppm 0.00091 ppm
4 hours 9.1e-06 ppm 0.00014 ppm 0.00048 ppm
8 hours 6.5e-06 ppm 9.5e-05 ppm 0.00035 ppm
(NAC/NRC, 2017)

ERPGs (Emergency Response Planning Guidelines)

No ERPG information available.

PACs (Protective Action Criteria)

Chemical PAC-1 PAC-2 PAC-3
Agent VX; (Ethyl-S-dimethylaminoethyl methylphosphonothiolate) (50782-69-9) 1.6e-05 ppm 0.00027 ppm 0.00091 ppm
(DOE, 2016)

Regulatory Information

EPA Consolidated List of Lists

Regulatory Name CAS Number/
313 Category Code
EPCRA 302
EHS TPQ
EPCRA 304
EHS RQ
CERCLA RQ EPCRA 313
TRI
RCRA
Code
CAA 112(r)
RMP TQ
Phosphonothioic acid, methyl-, S-(2-(bis(1-methylethyl)amino)ethyl) O-ethyl ester 50782-69-9 100 pounds 100 pounds

(EPA List of Lists, 2015)

DHS Chemical Facility Anti-Terrorism Standards (CFATS)

RELEASE THEFT SABOTAGE
Chemical of Interest CAS Number Min Conc STQ Security
Issue
Min Conc STQ Security
Issue
Min Conc STQ Security
Issue
VX; [o-Ethyl-S-2-diisopropylaminoethyl methyl phosphonothiolate] 50782-69-9 CUM 100 grams CW/CWP

(DHS, 2007)

OSHA Process Safety Management (PSM) Standard List

No regulatory information available.

Alternate Chemical Names