Ocular toxicity mustard

War I. More recent use occurred in Middle East conflicts. Its oily nature makes it persistent on surfaces it contacts. Because sulfur mustard exerts toxic effects following dermal, ocular, and inhalation exposure, its use necessitated fiill body protection which, in tmn, required the development of protective clothing and significant changes in warfare operations. 

Acute lethality data in animals are summarized in Table 8.7. Based upon the animal data, interspecies variability in the lethal response to sulfur mustard vapor is less than an order of magnitude. For nonlethal effects, the animal data suggest that test species exhibit signs of toxicity that are qualitatively similar to humans when acutely exposed to sulfur mustard vapor. Ocular and respiratory tract irritations are clearly evident in studies using dogs, rats, mice, rabbits, and guinea pigs. 

Ocular, percutaneous, inhalation, ingestion, and injection are all possible routes of exposure. Effects may be local, systemic, or both. All of the nitrogen mustards are oily liquids that are colorless to pale yellow and evaporate slowly. They are more dangerous than sulfur mustard but, like sulfur mustard, they are derivatives of ammonia. The most toxic and most volatile of the three nitrogen mustards is HN-2, but HN-3 is used more because it is stable. 

The second exception is that while an antidote is available for systemic effects of Lewisite exposure, there are no antidotes for nitrogen mustard or sulfur mustard toxicity, with one minor caveat if given within minutes after exposure, intravenous sodium thiosulfate may prevent death due to sulfur mustard exposure (25). Otherwise, the medical management for skin, ocular, and respiratory exposure is only supportive. One guideline physicians can follow is to keep skin, eye, and airway lesions free from infection. 

Recognizing the fact that ROS play a role in the pathogenesis of mustard-induced ocular injuries, compounds that inhibit the formation of ROS or prevent their toxic effects would be beneficial in the treatment of mustard-induced ocular injuries. The topical application of low concentrations of Zn/DFO or Ga/DFO after comeal exposure to nitrogen mustards markedly reduced conjunctival, comeal, iris, and anterior chamber injury. In the cornea, the healing of epithehal erosions was faster, the long-term opacification was reduced, and the levels of neovascularization were lowered. In the anterior chamber, decreased inflammation and better maintenance of intraocular pressure were achieved. Cataractous changes were also notably milder (Banin et al., 2003). 

Petrali JP, Oglesby SB, Mills KR. Ultrastructural correlates of sulfur mustard toxicity. J Toxicol Cutan Ocular Toxicol. 1990 9 193-204. 

Despite the twentyfold to thirtyfold increase in the toxicity of lewisite compared to the mustards, the ocular injuries caused by vapor exposure to lewisite are predicted to be less significant than HD under field conditions (Gates et al., 1946). Ocular irritation is almost immediate even at low concentrations, such that exposed personnel would be alerted to the presence of an irritant and able to rapidly take protective action. Second, the rapid onset of blepharospasm, ocular pain, and edema at low concentrations causes the eyes to close involimtarily, reducing the total ocular exposure. 

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