Detection of Sulfur Mustard Adducts in Eye Compartments Following Ocular Exposure in Rabbits

Background/Objectives: Sulfur mustard (SM) is an old warfare agent that remains a threat to both military personnel and civilians. SM contamination occurs through three main routes: dermal contact, inhalation, and ocular exposure. The clinical consequences of ocular exposure range from conjunctivitis and ulcerations to blindness. While these pathophysiological consequences are well-established, the mechanisms of action of SM in the eyes are not fully understood. Methods: The present study, which was conducted in rabbits, aimed at quantifying a series of biomarkers resulting from the electrophilic addition of SM to glutathione and nucleic acids in multiple biological matrices. This allowed us to investigate the distribution of SM within the ocular sphere and its diffusion to distant organs. Results: SM biomarkers were detected in large amounts in tears and aqueous humor but at substantially lower levels in the vitreous humor. No evidence of diffusion was observed from the exposed eye to plasma and distant organs, including the brain, liver, and lungs. Conclusions: These results are in agreement with a role for the cornea as a major sink for SM, thereby preventing damage to other ocular compartments and systemic diffusion.