Mustard gas is a corrosive poison and alkylating agent. After mustard gas is absorbed, some of it is metabolized into nontoxic or low-toxic products in the body, and some of it reacts with various biochemical components in the body, such as DNA, protein and enzymes. After DNA alkylation, the molecular structure is destroyed and cell mitosis is blocked, which affects cell proliferation. After RNA alkylation, amino acid uptake was affected, resulting in metabolic disorder of protein. Therefore, the tissue cells with vigorous proliferation are most sensitive to mustard gas, and nuclear fragmentation, nuclear disintegration and cell death occur when the dose is large. Cell death causes tissue inflammation, necrosis and late repair reaction. Lymphatic tissue, hematopoietic tissue, intestinal epithelial tissue, testicular spermatogenic tissue and other tissues with active cell division and vigorous metabolism are sensitive to mustard gas. After poisoning, lymphoid organs atrophy, hematopoietic tissue of bone marrow is destroyed, hematopoietic cells are reduced or disappeared, intestinal epithelial and glandular nuclei are concentrated and broken, villi edema, necrosis, mucosal shedding, submucosal inflammation and bleeding lead to diarrhea, hematochezia, loss of water and electrolyte, and severe cases can cause shock. When the dose is large, the central nervous system presents "toxic encephalopathy" In World War I, 12000 tons of mustard gas was consumed for war purposes; The number of gas casualties reached 6.5438+0.3 million.