Sulfur dioxide
Sulfur dioxide (SO₂) is a colorless gas known for its strong, pungent odor and significant role in air pollution. It primarily originates from the burning of fossil fuels, smelting of certain metals, and volcanic eruptions. While not flammable, sulfur dioxide can dissolve in water to form sulfuric acid, contributing to acid rain that harms soil and water sources. Human exposure typically occurs through inhalation of polluted air or skin contact, particularly affecting those living near industrial sites or active volcanoes, such as Hawaii Volcanoes National Park, where levels can be exceptionally high.
The gas poses various health risks, including irritation to the skin, eyes, and respiratory system, potentially exacerbating conditions like asthma and chronic bronchitis. Children are especially vulnerable due to their developing lungs. Additionally, sulfur dioxide functions as a food preservative, commonly found in dried fruits and other packaged foods. While it benefits food preservation, approximately one in a hundred individuals are sensitive or allergic to sulfites, which can lead to serious health reactions. Due to these risks, regulatory agencies, including the U.S. Food and Drug Administration, mandate labeling for foods containing significant sulfite levels.
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Sulfur dioxide
Sulfur dioxide (SO2) is a colorless gas with a strong, pungent odor that contributes to air pollution. It is mostly caused by burning fossil fuels (coal, natural gas, oil) and smelting mineral ores such as aluminum, copper, or iron. Volcanic activity also releases the pollutant into the air. Sulfur dioxide can cause ill health effects to humans, animals, and plants.
Sulfur dioxide is also used as a food preservative, especially in dried fruits such as raisins and prunes. It is a type of sulfite, which occurs naturally during the fermentation process when making wine. Some people are sensitive or allergic to sulfites. They can cause severe breathing issues in people who suffer from asthma, as well as other health issues.
Overview
Sulfur dioxide is released into the environment by burning fossil fuels, smelting metals, or by volcanoes. The gas is not flammable. It can move into the air and dissolve in water to form sulfuric acid. Acid rain contains sulfuric acid and can pollute soil and waterways. Sulfur dioxide also can cause damage to the exterior of buildings.
Most people are exposed to sulfur dioxide by breathing in polluted air or by skin contact. Active people who spend long periods outdoors can encounter sulfur dioxide. People living near active volcanoes, especially those who reside near Hawaii Volcanoes National Park, are at increased risk of sulfur dioxide exposure. The national park has very high levels of sulfur dioxide at times. Workers in plants or factories, or those who live near industrial plants that release sulfur dioxide as a byproduct, are also at an increased risk of coming into contact with high levels of the gas. Some of these industries include smelting, coal processing, and the manufacture of items such as sulfuric acid, paper, food preservatives, and fertilizers.
Sulfur dioxide causes an array of symptoms. It can irritate the skin, eyes, nose, throat, and lungs. It can damage and inflame the respiratory system and lungs, and lead to breathing issues, pain when breathing, a cough, and throat irritation. The pollutant can worsen the symptoms associated with asthma, chronic bronchitis, emphysema, and heart disease. Exposure to sulfur dioxide can exacerbate pre-existing conditions. Children are more adversely affected by it because their lungs are still developing.
Sulfur dioxide is also a type of sulfite, which is used as a preservative in dried fruits and other foods such as prepackaged jams, potato chips, crackers, juices, and condiments. Some people (about one in one hundred) have sensitivities or allergies to sulfites. These can cause mild to severe reactions—especially in people with asthma—and include breathing problems such as wheezing, allergy-like symptoms such as hives or swelling, and even death. Sulfites are common in wine, but wine only contains 20 to 350 parts per million of sulfites. Dried fruits contain much higher levels at 500 to 2,000 parts per million. Because of the severe reactions associated with sulfites, the US Food and Drug Administration (FDA) requires the labeling of food with more than 10 parts per million of sulfites. Other countries also require labeling, but their standards differ.
Bibliography
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