Lewisite is a colorless, odorless liquid when
pure. Industrially produced lewisite is an amber to dark brown
oily liquid with an odor of geraniums. It turns violet to black
or green with age. Odor is not a reliable indicator of the presence of toxic amount of vapor. Blister agent, lewisite (L) rapidly decomposes in relative humidity over 70%. Lewisite is a
complex mixture of several cis-and trans-isomer compounds.
In chemical agent grade lewisite, the L-1 isomer generally predominates. (L-1)
Toxic by inhalation and ingestion, strong irritant to skin and mucous membranes.
A poison by skin contact andsubcutaneous routes. When heated to decomposition itemits very toxic fumes of As and Cl-.
A potential danger to those involved
in the manufacture or use of this organo-arsenic warfare
agent which is a vesicant. L-1, L-2, and L-3 have been
used as a blister-agent type war gas
Mustard-lewisite mixture was developed to achieve a lower
freezing point for ground dispersal and aerial spraying
UN2810 Toxic liquids, organic, n.o.s., Hazard
Class: 6.1; Labels: 6.1-Poisonous materials, Technical
Name Required (Lewisite). UN3280 Organoarsenic compound, liquid, n.o.s., Hazard Class: 6.1; Labels: 6.1-
Poisonous materials, Technical Name Required (Lewisite),
Potential Inhalation Hazard (Special Provision 5). UN2927
Toxic liquids, corrosive, organic, n.o.s., Hazard Class: 6.1;
Labels: 6.1-Poisonous materials, 8-Corrosive material,
Technical Name Required (Lewisite). Military driver shall
be given full and complete information regarding shipment
and conditions in case of emergency. AR 50-6 deals specifically with the shipment of chemical agents. Shipments of
agent will be escorted in accordance with AR 740-32.
Lewisite reacts with water and sweat;
and, as it breaks down in water or sweat, it producesarsenic containing materials which are less dangerous than
lewisite but still dangerous. Heating causes lewisite to yield
arsenic trichloride, tris-(2-chlorovinyl)arsine, and bis-
(2-chlorovinyl)chloroarsine. Lewisite attacks copper, aluminum and its alloys. Mustard-lewisite mixture is rapidly
corrosive to brass at 65C and will corrode steel at a rate of
0.0001 in. of steel per month at 65C. It will hydrolyze into
hydrochloric acid, thiodiglycol, and nonvesicant arsenic
compounds. Lewisite hydrolyzes in acidic medium to form
hydrochloric acid and nonvolatile (solid) chlorovinylarsenous oxide, a less potent blister agent than lewisite. See the
emergency response cards for hydrochloric acid and chlorovinylarsenous oxide. Lewisite hydrolyzes in basic media, as
in decontamination with alcoholic, caustic, or carbonate
solution, to form acetylene and trisodium arsenate.
Contact with metals may evolve flammable hydrogen gas
