Coumarin, which was banned in foods in the United States in 1954, can cause serious harm to individuals who are on anti-coagulant medication or who regularly take low dose aspirin – also an anti-coagulant. Nevertheless, "Mexican vanilla" has found its way to some ethnic food stores and Mexican restaurants in the United States.
Not all imitation vanilla from Latin America is made from tonka beans. FDA has published a list of companies that use tonka beans to manufacture an imitation vanilla extract. Those companies using tonka beans are on "Import Alert" for automatic detention at the border.
FDA advises that consumers take the time to read ingredient labels carefully when purchasing inexpensive or imitation vanilla, especially when traveling in Latin America or when patronizing an ethnic food store.