CBRNE - Vesicants, Organic Arsenicals - L, ED, MD, PD, HL Clinical Presentation

Updated: Mar 30, 2022
  • Author: Geoffrey M Fitzgerald, MD; Chief Editor: Zygmunt F Dembek, PhD, MS, MPH, LHD  more...
  • Print


Victims of an lewisite (L) attack may remember observing puddles of a brown liquid or of smelling an odor similar to geranium. Methyldichloroarsine (MD) and ethyldichloroarsine (ED) reportedly smell like rotting fruit. Almost instantaneous pain and irritation of the skin, eyes, and nasal pharynx follow exposure. Patients usually relate a history of trying to remove themselves from the site of noxious stimuli.

Signs and symptoms are as follows:

  • The skin burns and itches. A history of erythema followed by the appearance of vesicles may be obtained.
  • Eye pain is severe and is accompanied by blepharospasm and/or photophobia.
  • Extreme irritation of the nasal mucosa and upper airway induces coughing and sneezing. Coughing may become productive, and shortness of breath may appear as the irritation of the airway mucosa progresses.
  • Phenyldichloroarsine (PD) often precipitates severe vomiting within 1-2 minutes after exposure.

Physical Examination

Physical signs of organic arsenical exposure are similar to those of mustard agents. The major difference is the time of onset of signs. Organic arsenicals cause immediate signs, whereas signs of mustard exposure appear after a latent period of several hours.

An erythematous rash appears within 15-30 minutes. This is followed by the development of vesicles, which initially are filled with clear fluid and may coalesce to form large bullae. In more severe exposures, the vesicular fluid may take on a yellow and then red color, and a central area of necrosis may form.

A lewisite (L) skin lesion has more actual tissue destruction (but less surrounding erythema) than a mustard lesion. Compared with distilled mustard, lewisite (L) is gram-for-gram more toxic. The LD50 (lethal dose for 50% of the population) of lewisite (L) is 2.8 g on the skin.

Conjunctival injection and edema of the lids, cornea, and conjunctiva occur with either a vapor or liquid exposure. Corneal vascularization with secondary edema results and may last for weeks. [6]

One drop of liquid lewisite (L) on the cornea can cause severe corneal damage up to and including perforation.

Vapor damage to the upper respiratory mucosa causes epistaxis, massive rhinorrhea, and lacrimation. Laryngitis and dysphonia changes result from exposure and can lead to laryngospasm.

With larger vapor exposure, destruction of the bronchiolar mucosa and submucosa causes pseudomembrane formation and obstruction.

Systemic signs of organic toxicity may include evidence of hypovolemia and shock.