Sulfur Mustard - Physiological Effects

Physiological Effects

Mustard gas has extremely powerful vesicant effects on its victims. In addition, it is strongly mutagenic and carcinogenic, due to its alkylating properties. It is also lipophilic. Because people exposed to mustard gas rarely suffer immediate symptoms, and mustard-contaminated areas may appear completely normal, victims can unknowingly receive high dosages. Within 24 hours of exposure to mustard agent, victims experience intense itching and skin irritation, which gradually turns into large blisters filled with yellow fluid wherever the mustard agent contacted the skin. These are chemical burns and are very debilitating. Mustard gas vapour easily penetrates clothing fabrics such as wool or cotton, so it is not only the exposed skin of victims that gets burned. If the victim's eyes were exposed then they become sore, starting with conjunctivitis, after which the eyelids swell, resulting in temporary blindness. Miosis may also occur, which is probably the result from the cholinomimetic activity of mustard. At very high concentrations, if inhaled, mustard agent causes bleeding and blistering within the respiratory system, damaging mucous membranes and causing pulmonary edema. Depending on the level of contamination, mustard gas burns can vary between first and second degree burns, though they can also be every bit as severe, disfiguring and dangerous as third degree burns. Severe mustard gas burns (i.e. where more than 50% of the victim's skin has been burned) are often fatal, with death occurring after some days or even weeks have passed. Mild or moderate exposure to mustard agent is unlikely to kill, though victims require lengthy periods of medical treatment and convalescence before recovery is complete. The mutagenic and carcinogenic effects of mustard agent mean that victims who recover from mustard gas burns have an increased risk of developing cancer in later life.

Skin damage can be reduced if povidone-iodine, (Betadine), in a base of glycofurol is rapidly applied, but since mustard agent initially has no symptoms, exposure is usually not recognised until skin irritation begins, at which point it is too late for countermeasures. The vesicant property of mustard gas can be neutralised by oxidation or chlorination, using household bleach (sodium hypochlorite), or by nucleophilic attack using e.g. decontamination solution "DS2" (2% NaOH, 70% diethylenetriamine, 28% ethylene glycol monomethyl ether) can be used. After initial decontamination of the victim's wounds is complete, medical treatment is similar to that required by any conventional burn. The amount of pain and discomfort suffered by the victim is comparable as well. Mustard gas burns heal slowly, and, as with other types of burn, there is a risk of sepsis caused by pathogens such as Staphylococcus aureus and Pseudomonas aeruginosa.

A British nurse treating soldiers with mustard gas burns during World War I commented:

They cannot be bandaged or touched. We cover them with a tent of propped-up sheets. Gas burns must be agonising because usually the other cases do not complain, even with the worst wounds, but gas cases are invariably beyond endurance and they cannot help crying out.