As many as 500,000 Americans are estimated to be allergic to sesame seeds, but current rules on allergen labeling don’t include a requirement for them. The Center for Science in the Public Interest (CSPI), a Washington, D.C., consumer advocacy organization, is now asking the U.S. Food and Drug Administration to add sesame seeds to its list of allergens that require clear labeling on the ingredients list. Specifically, the group has filed a citizens petition asking FDA to mandate labels for foods that contain sesame seeds or were made with machinery that also processes foods that include sesame seeds. Such labels already exist for allergens such as milk, eggs, peanuts and wheat. For those with an allergy to sesame seeds, accidentally consuming them can trigger “life-threatening anaphylaxis,” CSPI says. Ingredients that contain sesame seeds are sometimes listed as tahini or gingelly, and those names might not register with some consumers looking to avoid the seeds. Ingredients labeled “natural flavorings” or “spices” also have the potential to include sesame seeds. In a news release, CSPI highlighted the case of a 10-year-old boy in Virginia who was rushed to the emergency room after eating a meal at a restaurant, despite his parents getting the assurance of the staff before ordering that the meal contained no sesame seeds. That boy’s father, Brian Heller, launched a petition on in October asking FDA to treat sesame seeds as a major allergen. Canada, Australia and the European Union all require the explicit labeling of sesame seeds.