Sulfur Dioxide E220
inorganic — Primarily synthetic.
Sulfur dioxide
CAS: 7446-09-5
Factual Regulatory Reference
This database provides factual regulatory information compiled from official government sources. It does not constitute medical, nutritional, or safety advice. Regulatory status varies by country and is subject to change. Always refer to your local regulatory authority for the most current information.
What Is Sulfur Dioxide?
Sulfur dioxide (E220) is one of the oldest known food preservatives, used since ancient times in winemaking by burning sulfur to sterilize vessels. It functions as a preservative, antioxidant, and anti-browning agent in wines, dried fruits, fruit juices, preserved vegetables, and certain processed foods. Sulfur dioxide is highly reactive and inhibits both oxidative browning enzymes and microbial growth, making it particularly valuable in wine production to prevent undesired fermentation and oxidation. Sulfites (E220-E228) are recognized allergens that can trigger severe asthmatic reactions and other hypersensitivity responses in sulfite-sensitive individuals; EU law requires declaration on food labels when total sulfite content exceeds 10 mg/kg expressed as SO₂. EFSA evaluated the group ADI for sulfur dioxide and sulfites and established 0.7 mg SO₂ equivalents/kg body weight per day.
? Did You Know?
Sulfur Dioxide occurs naturally in Volcanic gases and produced during wine fermentation. Many people consume it daily without realizing it's also a listed food additive.
Sulfur Dioxide isn't just a food additive — it's also used in industrial applications.
Regulatory Analysis
Sulfur dioxide (E220) and the sulfite group (E220–E228) present a case where the primary regulatory challenge is not toxicology in average consumers but hypersensitivity in a susceptible subpopulation. The pivotal US regulatory event was the 1986 FDA ban on sulfites in fresh produce after deaths were linked to sulfite-treated salad bar vegetables; this targeted intervention left wine and dried fruit applications intact. EFSA's 2016 group re-evaluation maintained the ADI at 0.7 mg SO₂ equivalents/kg body weight per day, while noting that wine-drinking adults consuming sulfite-containing dried fruits may approach this limit. Because sulfites are recognized allergens, EU Regulation (EC) No 1333/2008 mandates label declaration when sulfite levels exceed 10 mg/kg, making transparency — rather than restriction — the central regulatory instrument.
Detailed Regulatory Assessment
European Union (EFSA)
Must be declared on labels; allergen concern for sensitive individuals (especially asthmatics)
United States (FDA)
Must be declared on labels; banned from fresh fruits and vegetables (except grapes) since 1986
Japan (MHLW)
Compliant with Japanese food sanitation law.
Acceptable Daily Intake (ADI)
International Standard (JECFA)
mg/kg body weight per day
European Standard (EFSA)
Natural Occurrence
A gas produced naturally during fermentation and volcanic activity, but the food additive is produced industrially.
Manufacturing
Produced industrially by burning sulfur or roasting sulfide ores.
Applications Beyond Food
Used in paper manufacturing, water treatment, and as a reducing agent.