Tossing Sulfites Out of Salads

By Anastasia Toufexis

Crisp green lettuce. Pulpy red tomatoes. Moist orange melons. The heaping displays at salad bars in supermarkets and restaurants across the nation are as appealing to the eye as they are tempting to the palate. For many people, building a salad to order is a bountiful, healthful new ritual. But for some there is a hidden canker. To keep fruits and vegetables tantalizingly fresh, produce has often been sprayed or dipped in sulfite solutions that prevent wilting and discoloration. Sulfites were long considered safe, but in recent years their skyrocketing use has brought disturbing reports. At least twelve deaths have been linked to sulfites since 1982. An additional 850 people have reported allergy-like reactions to the chemicals, 80% after eating sulfite- laced fruits and vegetables at salad bars and restaurants.

This fall, after almost three years of study, the Food and Drug Administration will impose a ban on the use of six sulfite preservatives in fresh produce. Not waiting for the ban, many supermarkets and restaurants have already stopped using the substances, sometimes substituting diluted citric acid or lemon juice. "The ban is a step in the right direction," Attorney Mitchell Zeller of the Washington-based Center for Science in the Public Interest concedes. "But the public is by no means protected." About 7 million lbs. of sulfites are now used in the U.S. each year, on far more than fresh produce. Vintners rely upon sulfites to arrest fermentation and block the growth of bacteria in wine. They are routinely added to make cake and cookie mixes less sticky and to preserve canned and frozen vegetables, dried fruits, instant mashed-potato mixes, breads, salad dressings, fruit juices and soft drinks.

Consumers wishing to avoid the chemicals in such products have a tough time. Sulfites added as preservatives must be listed on packaged foods, but that does not guarantee the information is complete. Supermarket stickers traditionally do not acknowledge the chemicals' use in processing shrimp and other shellfish. Wine labels do not note sulfites either. People dining out also have trouble getting guidance. Restaurateurs say that much of the food they serve is processed elsewhere, and suppliers' assurances that a preparation is sulfite free can be faulty.

For most people, the chemicals pose no danger. Still, a sizable number are apparently sensitive to sulfites. Their reactions range from hives, nausea, diarrhea and shortness of breath to shock, coma and brain damage, as well as death. Asthmatics appear to be at greatest risk. The FDA estimates that 450,000 asthma sufferers, or 5%, are sulfite sensitive. For many, suggests Immunologist Ronald Simon of the Scripps Clinic and Research Foundation in La Jolla, Calif., the problem stems from sulfur dioxide, which is released by the sulfite solution. The fumes cause spasms in the bronchial tubes, preventing oxygen from getting into the lungs and blood. Notes Dr. Simon: "Asthmatics are exquisitely sensitive to sulfur dioxide."

To safeguard the public, the Center for Science is urging an outright ban on all use of sulfites. But others note that very few ill effects are documented from sulfites in packaged foods and that there is no substitute for them in making wine. Of the twelve sulfite-associated deaths, only one was caused by wine, one by beer and one by hashed brown potatoes. The rest were all linked to fresh fruits or vegetables. Asthmatics and others who suspect they are sensitive can be tested. Those who test positive should stay away from wine. And they should not go to salad bars, at least until the ban goes into effect.

With reporting by Patricia Delaney/Washington and Melissa Ludtke/Los Angeles