Sulfiting agents, including sulfur dioxide, potassium metabisulfite, sodium sulfite, sodium metabisulfite, sodium bisulfite, and potassium bisulfite, are effective antioxidants. As such they are used widely as additives in processed beverages and foods, including fruit juices, soft drinks, wines, beers, cider, vinegar, potato chips, dried fruits, and vegetables.1 Their antibrowning property makes them useful in preventing spoilage of commercially prepared or displayed fresh foods such as ingredients of salad bars, dips, seafoods (particularly shrimp), fruits, and vegetables. One also encounters sulfur dioxide as a common air pollutant. Koepke et al2 point out still another source of exposure—use of medications containing these substances. The irony of their observation is not lost on a profession whose guiding words are primum non nocere. The case history they describe is of an asthma patient with presumed sulfite sensitivity whose prescribed bronchodilator contains a sulfiting agent.
The adverse effects of ingested sulfiting agents in