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Emergency Response Card: Information for First Responders - Blister Agent: Lewisite

BLISTER AGENT

CAS # 541-25-3
RTECS #
Counter Terrorism Card 0020

LEWISITE
L
2-chlorovinyldichloroarsine
2-chlorovinylarsonous dichloride
(2-chloroethenyl)arsonous dichloride
Dichloro- (2-chlorovinyl) arsine
SEE NOTES
Chemical Formula C₂H₂AsCl₃
Molecular mass: 207.32

TYPES OF HAZARD/ EXPOSURE	ACUTE HAZARDS/ SYMPTOMS	PREVENTION	FIRST AID/ FIRE FIGHTING
FIRE			Water, fog, foam, CO₂. Avoid methods that cause splashing or spreading.
EXPLOSION
EXPOSURE	Severe irritant. Contact with vapor or liquid can be fatal.	Do not breathe fumes. Skin contact must be avoided at all times.	Seek medical attention Immediately.
INHALATION	Immediate burning pain. Profuse nasal secretions and violent sneezing. Cough and frothing mucous. Lung edema. Systemic poison causing restlessness, weakness, subnormal temperature and low blood pressure.	Hold breath until respiratory protective mask is donned. Fire-fighting personnel should wear full protective clothing and respiratory protection during fire-fighting and rescue. Positive pressure, full face piece, NIOSH-approved self-contained breathing apparatus (SCBA) will be worn.	If breathing difficult give oxygen. If breathing stopped give artificial respiration. Mouth-to-mouth only when no facial contamination.
SKIN	Immediate stinging pain. Skin redness within 30 minutes with pain and itching for 24 hours. Blisters within 12 hr. with pain lasting 2-3 days. Deep skin burns. See Inhalation	Protective Gloves: Butyl Rubber Glove M3 and M4 Norton, Chemical Protective Glove Set	The primary mode for decontamination of chemical agents is soap and water. A 0.5% hypochlorite solution can be used. There are differing guidelines for decontamination and more research is needed to identify the optimal decontamination method. See "Personal Decontamination" and "Appendix D" in Treatment of Chemical Agent Casualties and Conventional Military Chemical Injuries (from the U.S. Navy Counterproliferation Office). See also the Medical Management of Chemical Casualties Handbook (from the U.S. Army Medical Research Institute of Chemical Defense [USAMRICD]) for a general review of the issues and more on the military decontamination powder approach.
EYES	Instant pain, irritation and swelling of eyelids. Corneal scarring and iritis. Severe permanent damage or blindness within 1 min.	Chemical goggles and face shield.	Immediately flush eyes with water for 10-15 minutes.
INGESTION	See Inhalation		Do not induce vomiting. Give victim milk to drink.

DECONTAMINATION

SPILLAGE DISPOSAL

PACKAGING & LABELLING

The effect of Lewisite can be prevented by rapid topical application of 2,3-dimercaptopropanol, known as British anti-Lewisite (BAL) which reacts with Lewisite to form a stable non-toxic cyclic product.

Cover with vermiculite, diatomaceous earth, clay, or fine sand and neutralize as soon as possible using large amounts of alcoholic caustic, carbonate, or Decontaminating Agent (DS2). Caution: acetylene given off. Household bleach can also be used if accompanied by stirring to allow contact. Scoop up all material and place in an approved container. After sealing, decontaminate the exterior and label. All leaking containers will be packed with sorbent (e.g. vermiculite) placed between the interior and exterior containers. Label and dispose according to regulations. Conduct general area monitoring.

Proper Shipping Name: Toxic liquids, organic, n.o.s.
DOT Hazard Class: 6.1, Packing Group I, Hazard Zone A.
DOT Label: Poison.
DOT Marking: Toxic liquids, organic, n.o.s. (O-ethel S-(2-diisopropylaminoethyl)methylphosphonothiolate) UN 2810, Inhalation Hazard.
DOT Placard:

NFPA 704 Signal:

Health - 4
Flammability - 1
Reactivity - 1
Special - 0

I
M
P
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T
A
N
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D
A
T
A

PHYSICAL STATE ; APPEARANCE:
Industrially-produced Lewisite is amber to dark brown liquid and has a strong penetrating geranium odor; the pure compound is a colorless, odorless, oily liquid.

PHYSICAL DANGERS:

CHEMICAL DANGERS:
Hydrolyses rapidly in water and in acidic medium to form HC1 and non-volatile (solid) chlorovinylarsenious oxide. Hydrolysis in alkaline medium (e.g., alcoholic caustic, carbonate solution or DS2) produces acetylene and trisodium arsenate (Na₃As0₄) in solution containing toxic arsenic.

OCCUPATIONAL EXPOSURE LIMITS (OELs):
TLV : 0.003 mg/m³ (ceiling value)

ROUTES OF EXPOSURE:
The substance can be absorbed into the body by all routes.

INHALATION RISK:
Severe irritation and lung edema. Can cause systemic poisoning leading to hemoconcentration, shock, and death. Non-fatal hemolysis results in anemia. Metabolites excreted by liver into bile produce focal necrosis of liver, biliary passages, and injury to intestine.

EFFECTS OF SHORT-TERM EXPOSURE:
See Inhalation Risk. Large skin burns may cause lung edema, diarrhea, restlessnesss, weakness, subnormal temperature and low blood pressure.

EFFECTS OF LONG-TERM OR REPEATED EXPOSURE:
Can cause sensitization and chronic lung impairment. Suspected carcinogen.

PHYSICAL
PROPERTIES

melting point: -18°C
boiling point: 190°C
vapor pressure (20°C): 0.35 mm Hg
density (20°C): 1.89 g /cm³
volatility: 2,500 mg/m³ at 20°C
specific gravity: 1.891 at 20°C

aqueous solubility: 0.5 g/L
Insoluble dilute mineral acids.
Soluble in organic solvents, oils and alcohol.
estimated log K_ow: 2-3
log K_{benzene-water}: 0.15
flashpoint: Does not flash.
flammability: Not Applicable

ENVIRONMENTAL
DATA

Stable in steel or glass containers below 50 °C.
Lewisite and its hydrolysis products are not significantly transformed in sunlight.
Lewisite and its hydrolysis products are thermally stable at temperatures less than 49°C.

N O T E S

Lewisite is a complex mixture of several cis- and trans-isomer compounds. In chemical agent grade Lewisite, the L-1 isomer [2-Chlorovinylarsonous dichloride] generally predominates. The three homologues, L-1, L-2 [Bis(2-chlorovinyl)arsinous chloride], and L-3 [Tris(2-chlorovinyl)arsine] form from the catalyzed reaction of arsenic trichloride and acetylene. L-1 forms initially, but it continues to react with acetylene to form L-2 and L-3. L-1 is the vesicant agent. L-2 and L-3 are also toxic, but considerably less than L-1.

ADDITIONAL INFORMATION

Trade Names and Other Synonyms:

Arsine, (2-chlorovinyl) dichloro-
Arsonous dichloride, (2-chloroethenyl)
Chlorovinylarsine dichloride
Beta-Chlorovinyldichloroarsine
EA 1034

IMPORTANT NOTICE:

LEWISITE (CTC: 0020) Neither the CDC or NIOSH nor any person acting on behalf of the CDC or NIOSH is responsible for the use which might be made of this information. This card contains the collective views of these agencies and may not reflect in all cases all the detailed requirements in response to a terrorism event on the subject. The user should verify compliance of the cards with the relevant STATE or TERRITORY legislation before use. NIOSH, CDC 2000

Page last modified July 10, 2002
Page last reviewed April 6, 2005

Emergency Response Card: Information for First Responders - Blister Agent: Lewisite

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