Figure 2. Overview of Proposed Mechanisms of Toxicity for Sulfur Mustard.

(A) SM can cause apoptosis via the FAS/FASL pathway. (B) SM alkylates DNA, RNA, and proteins. DNA alkylation leads to single and double-strand breaks, which leads to the activation of PARP. Overactivation of PARP leads to NAD⁺ depletion and necrosis. While RNA and protein alkylation don’t lead directly to cell death, lack of antioxidants increases intracellular Ca²⁺ and alters cell morphology. (C) SM’s damage and toxicity causes epithelial damage leading to a robust inflammatory response through macrophages, neutrophils, and mast cells. (D) SM causes mitochondrial dysfunction, immune cell accumulation (macrophage and neutrophils), leading to a respiratory burst of reactive oxygen species (ROS), nitric oxide (NO), and necrotic cell death. Figure created with biorender.com