News from FDA about allergens and E.coli outbreak in lettuce management

Today the US FDA published two important updates. The one about allergens is of particular interest in light of recent parallels publications from FAO/WHO Committees:

1. FDA and USDA Scientists Research Seasonal Effects Linked to E.coli Outbreaks in Bagged Romaine

Scientists from the U.S. Food and Drug Administration’s Center for Food Safety and Applied Nutrition and the U.S. Department of Agriculture’s Agricultural Research Service (USDA ARS) have been working collaboratively to understand the seasonal effects and other factors that may be contributing to outbreaks of E.coli O157:H7 linked to bagged romaine lettuce – and they are making significant progress. Leafy greens, including bagged romaine lettuce, have been implicated in outbreaks of foodborne illness caused by Shiga toxin-producing E. coli (STEC), the most common of which is E. coli O157:H7.

In a study recently published in the BMC Environmental Microbiome, FDA and USDA scientists presented findings which reveal that season, and lettuce shelf life, can influence the bacterial communities and behavior of E. coli O157:H7 on cut lettuce stored in modified atmosphere packaging. The scientists found that E. coli O157:H7 survived significantly better in cold-stored packaged romaine harvested in the fall than on the same varieties harvested in late spring. The research team also demonstrated that the microbiome present on bagged romaine differed by season, lettuce deterioration state, and whether the survival of E. coli O157:H7 on the lettuce was high or low. For example, the team found that E.coli O157:H7 survived better in lettuce that was harvested in the fall than lettuce harvested in the spring during cold storage. The analysis demonstrated how trends in E. coli survival correlated with trends in microbiome composition.

A microbiome is a community of microorganisms (such as bacteria, fungi, and viruses) that inhabit a particular environment. To conduct this work, USDA ARS cultivated two romaine lettuce types with different shelf life in Salinas, CA. The lettuce was grown and harvested in the spring and fall and then processed as fresh-cut product. The product was then inoculated with E. coli O157:H7 before all of it was packaged in modified atmospheric packaging (MAP) and stored at either cold or warm temperatures. The FDA then contributed cutting-edge genomic sequencing tools to characterize the microbiome composition present on the various lettuce samples.

This study provided insight into the relationship between the lettuce microbial ecology and the potential for E. coli O157:H7 survival during cold storage. This is a significant step toward closing the knowledge gaps identified in the FDA’s Leafy Greens STEC Action Plan and helping the agency and its partners to reduce foodborne illnesses linked to the consumption of leafy greens.

2. FDA Issues Draft Guidance on Evaluating the Public Health Importance of Food Allergens Other Than the Major Food Allergens

Today, the U.S. Food and Drug Administration (FDA) issued a draft guidance for FDA staff and other stakeholders titled Evaluating the Public Health Importance of Food Allergens Other Than the Major Food Allergens Listed in the Federal Food, Drug, and Cosmetic Act. The draft guidance, when finalized, will outline the FDA’s current thinking on the approach we generally intend to take when we evaluate the public health importance of food allergens that are not one of the major food allergens identified by law in the U.S. The major food allergens are milk, eggs, fish, crustacean shellfish, tree nuts, peanuts, wheat, and soybeans. Sesame becomes the ninth major food allergen effective January 1, 2023. For the purposes of this draft guidance, we refer to food allergens that are not major food allergens as non-listed food allergens.

Food allergies and other types of food hypersensitivities affect millions of people living in the U.S. and there are more than 160 known food allergens. To protect those with food allergies and other food h

This draft guidance is part of FDA’s efforts to evaluate emerging evidence about non-listed food allergens in a consistent and transparent manner to inform potential future actions. The FDA’s approach to non-listed food allergens focuses on immunoglobulin E antibody (IgE)-mediated food allergies, which are considered the most severe and immediately life-threatening food allergies. The draft guidance discusses the scientific evidence that establishes food as a cause of IgE-mediated food allergy and the scientific factors, such as prevalence, severity, and allergenic potency, that the FDA intends to consider in its evaluations. The draft guidance also provides the FDA’s recommendations for identifying and evaluating the relevant body of evidence to determine the public health importance of a non-listed food allergen.

The draft guidance also includes information on how stakeholders may submit requests to the FDA to evaluate the public health importance of a non-listed food allergen. We propose stakeholders submit data demonstrating that the food causes IgE-mediated allergy, together with data on the prevalence of the food allergy, the severity of the allergic reactions, and allergenic potency of the food allergen for the agency to consider in its review. We also propose that stakeholders provide other information, such as the information about the labeling and production of food containing the non-listed food allergen.

(Source: FDA CFSAN)