Mustard gas and cancer
Mustard gas, also known as sulfur mustard, is a chemical warfare agent that has been recognized as a known human carcinogen since 1980. Initially used during World War I, it is a potent blistering agent that can cause severe burns, respiratory issues, and long-term health complications. Exposure to mustard gas primarily occurs through inhalation or skin contact, leading to symptoms that can develop within hours, including blistering, pain, and respiratory distress. The carcinogenic properties of mustard gas stem from its ability to chemically alter DNA, potentially leading to mutations that can result in various cancers, particularly respiratory cancers such as those of the larynx, pharynx, and lungs. Studies indicate that individuals who have been exposed, including military personnel and workers in production settings, exhibit an increased risk of developing these types of cancer. Interestingly, the destructive effects of mustard gas on white blood cells also contributed to the development of chemotherapy treatments for cancer, showcasing a paradox in its use. The international community has taken steps to regulate and prohibit mustard gas under various treaties, reflecting the recognition of its dangers in both warfare and health contexts.
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Mustard gas and cancer
ROC STATUS: Known human carcinogen since 1980
ALSO KNOWN AS: HD, senfgas, sulfur mustard, blister gas, s-lost, lost, Kampfstoff LOST, yellow cross liquid, yperite
RELATED CANCERS: Cancers of the larynx, pharynx, upper respiratory tract, and lungs
DEFINITION: Mustard gas is a member of the sulfur mustards, blister-inducing agents (vesicants). Mustard gas is actually a liquid at room temperature that is clear to yellow or brown in color and is either odorless or smells like garlic, onions, or mustard. Mustard gas was originally introduced as a chemical weapon during World War I and has been used throughout the world since then. It is a powerful irritant that damages the eyes and respiratory tract and causes large blisters on exposed skin.
Exposure routes: Inhalation and dermal contact
Where found: Used during chemical warfare attacks and in research laboratories.
At risk: Military personnel or civilians exposed to mustard gas during chemical warfare attacks, workers who manufacture it, and people who live near stockpiles of it or come into contact with unexploded ordinances loaded with it
ETIOLOGY AND SYMPTOMS OF ASSOCIATED CANCERS: Because mustard gas often has no odor, people are unaware that they have been exposed to it until the onset of symptoms, which usually begin two to twenty-four hours after exposure. Symptoms include redness, itching, yellow blistering of the skin, pain, swelling and tearing of the eyes, runny nose, sneezing, hoarseness, shortness of breath, sinus pain, bloody nose, cough, abdominal pain, diarrhea, fever, nausea, and vomiting. More severe exposures can cause second-to-third-degree burns of the skin, light sensitivity in the eyes, severe pain, blindness, chronic respiratory disease, and death.
Mustard gas is an alkylating agent that chemically alters the nitrogenous bases in deoxyribonucleic acid (DNA). Alkylation of DNA damages it and generates mutations but can also cause chromosome breakage. Mustard-gas-induced mutations cause either cell death or transformation into a tumor cell. Therefore, mustard gas is a confirmed carcinogen in humans and animals, and exposure to it increases a person’s risk for respiratory and lung cancer, according to the National Toxicology Program's fifteenth edition of the Report on Carcinogens in 2021.
According to the American Cancer Society, most people with lung cancer will not experience symptoms until the cancer has progressed to a later stage, but normally, the symptoms include cough, shortness of breath, wheezing, chest pain, and coughing up blood (hemoptysis). Nonspecific symptoms include weight loss, weakness, fatigue, depression, and mood changes. The spread of the cancer decreases lung capacity, and patients die because they are unable to acquire sufficient quantities of oxygen.
History: During World War I, the German army first used mustard gas in July 1917 against British soldiers near the Belgian city of Ypres. Since then, mustard gas has been used globally, but sporadically, in modern warfare.
Epidemiological studies from the 1970s and 1980s established that soldiers and production workers exposed to mustard gas for longer periods of time showed an increased risk of respiratory cancers.
The Geneva Protocol of 1925, which was modified and extended into the Chemical Weapons Convention of 1993, prohibits the development, production, and stockpiling of chemical weapons, including mustard gas.
Ironically, while mustard gas was being studied as a known carcinogen, its usefulness in medicine also became apparent. Medical researchers noticed that patients exposed to mustard gas had decreased white blood cell counts, and their bone marrow and lymphatic tissue were destroyed. Nitrogen mustard, an effective treatment for lymphoma, was developed from these observations. These discoveries laid the groundwork for chemotherapy, a first-line defense against cancer in the twenty-first century, as they showed that certain chemicals could kill cancer cells.
Bibliography
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