A 40-year-old Kurdish émigré presents to your
office accompanied by his daughter who translates for him. As a
teenager, his village was gassed by the Iraqi military. He developed
diffuse skin erythema over most of his body, profound eye pain and
photophobia, and blepharospasm. No blisters developed, but within
several hours he noticed mild upper airway irritation and a dry
cough. He did not have any shortness of breath. Within a few days,
he noticed his skin became dark and some areas desquamated. In the
following six months he had recurrent respiratory and skin infections,
but he has been otherwise well for the past twenty-four years. His
exam is significant for patchy areas of hyperpigmentation.
There are two major classes of vesicants: the mustards and the
arsenicals. Each class is discussed using a prototypical agent.
A third agent, often classified with the vesicants, is phosgene
oxime. This compound is poorly understood, but a brief discussion
is warranted and can be found at the end of this chapter. Vesicants
are more “strategic” in so far as they tend to
injure rather than kill (compared to other classes of chemical weapons.)
They cause injury by blistering whatever part of the body is exposed—internal
or external. They may be released via bombs or aerosolized through
Mustards were identified in the early to mid-1800s, while arsenicals
were developed in the United States during WWI. Although first used
in 1917, three years into WWI and three years after the military
use of chlorine gas began, mustards resulted in more WWI casualties
than all the other chemical weapons combined—accounting
for upward of 80% of all chemical agent causalities. Vesicants
have been used since WWI, most notably by Iraq during the 1980s.
The Iran–Iraq war inflicted an estimated 50,000 casualties,
mostly against Kurdish Iraqis in northern Iraq. At present, no antidote
exists for mustard gas. This is unfortunate as nearly a dozen countries
maintain mustard as part of their cadre of chemical agents. In contrast
to their use as chemical weapons, members of this class have found
use as chemotherapy for certain types of cancers.
Mustards, including the nitrogen and sulfur types, are thought
to be named for the pungent odor or from the yellow-brown color.
They are among the most persistent of the chemical agents. Historically
and militarily, sulfur mustards have played a bigger role and are
felt to be more of a threat as a weapon of terror. Nitrogen mustards
are considered battlefield agents and so are less likely to be encountered
by the public (Fig. 24–1), but are discussed briefly as
Gas shells exploding on WWI frontlines.
Courtesy of the World War I Document Archive.
The chemical structure of mustard results in a highly reactive