(NEW YORK) -- Food labeling in the United States has undergone significant changes over the past decade to prevent customers from experiencing allergic reactions, but there's still a long way to go, experts say.
"It's a very difficult topic to find a perfect solution for," said Dr. Scott Sicherer, a professor and researcher at the Jaffe Food Allergy Institute at Mount Sinai Hospital in New York. "Companies can always make a mistake and have recalls if a product is found to have a mislabeled an ingredient in it. Unless someone gets sick from it, they wouldn't know it was there."
The Food and Drug Administration and manufacturers have issued 20 recalls in the last 60 days for undeclared allergens in food products, including Chicken of the Sea tuna, which had undeclared soy; two kinds of Wegmans brownie mix with undeclared milk; and two kinds of ice cream with undeclared pecans, according to FDA records.
An ABC News analysis found more than 400 recalls for undeclared allergens in food reported to the FDA since March 2009. More than 140 of them were for desserts and snack foods, like cookies, candy and ice cream. Repeat brand recalls were often from grocery stores, such as Kroger, Publix, Whole Foods Market and Wegmans.
Eggs, fish, milk, peanuts, shellfish, soy, tree nuts and wheat make up 90 percent of food allergies, according to a 2008 Centers for Disease Control and Prevention report that found an 18 percent rise in children diagnosed with food allergies between 1997 and 2007.
Federal law requires manufacturers to list the top eight allergens on food labels in plain English -- "milk" instead of "casein," for example. The law, called the Food Allergen Labeling and Consumer Protection Act of 2004, went into effect in 2006.
But other allergens, like sesame, don't have to be called out on food labels. It's also possible that products that don't contain an allergen can become contaminated with it if the allergen-free product is made or packaged in the same factory as a product containing that allergen.
"Advisory labeling, some people call this precautionary labeling," Sicherer said, "those types of comments are totally voluntary. They're not part of the law."
As such, the labels aren't consistent with one another. Labels can say "may contain peanuts," or "made in a facility that also processes nuts," which many allergic people find confusing. It's possible a manufacturer failed to write an advisory or that the manufacturer over-labeled on items that were at low risk for contamination.
Food safety lawyer Bill Marler said he's never had a case in which someone had an allergic reaction because a manufacturer failed to say it intentionally put nuts or milk in its product, but he's had cross-contamination cases.
"I think there's probably a lot more of these not-straight-up labeling issues," he said. "I do think the manufacturing process is open to mistakes being made, especially when they're making multiple types of food in the same facility."
Dr. Donna Hummell, an allergist at the Monroe Carell Jr. Children's Hospital at Vanderbilt University said chocolate and candy are often especially risky foods for people with nut allergies to eat.
"If you can buy it with almonds in it or buy it plain or buy it with peanuts in it, it's better to watch out," Hummell said.
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