FSIS Announces Nationwide Expansion Of Listeria Environmental Sampling At Ready-to-Eat Establishments

The U.S. Department of Agriculture’s Food Safety and Inspection Service (FSIS) announced that it will expand nationwide its recent pilot program that added food-contact surface (FCS) and non-food-contact surface (non-FCS) environmental sampling at ready-to-eat (RTE) establishments.¹ FSIS plans for a phased implementation across all nine FSIS districts beginning in January 2027 and continuing through March 2027.

Expansion of Pilot Project

Earlier this year, FSIS announced the launch of an environmental sampling pilot project in the Alameda, Chicago, and Raleigh districts. FSIS positioned the pilot as part of broader agency efforts to enhance Listeria prevention and verification following listeriosis outbreaks associated with FSIS-regulated products in 2024. Results from the pilot project have not been published.

Consistent with the pilot project, under the expanded sampling program, inspectors will take four environmental swabs at the same time RTE product samples are collected under the existing RTEPROD sampling program. The samples will consist of two FCS swabs and two non-FCS swabs, each of which will be analyzed for both Listeria monocytogenes (Lm) and non-LmListeria species.

FSIS requires that establishments hold finished product when there are test results pending that could show the product to be adulterated, however, FSIS believes that aligning the FCS testing with the existing RTEPROD finished product sampling would minimize additional product holds.

The same swabbing procedures, laboratory methods, reporting, and follow-up actions already employed under the RLm and Intensified Verification Testing programs will be used to administer the program. Importantly, if the sampling identifies Lm, whole genome sequencing (WGS) will be performed and compared to reported illnesses or other historical results.

FSIS plans to phase implementation across the agency's nine districts as follows:

• January 2027: Alameda and Atlanta
• February 2027: Raleigh, Springdale, and Denver
• March 2027: Chicago, Philadelphia, Des Moines, and Dallas

FSIS will train both inspection personnel responsible for collecting samples and supervisors as part of the phased implementation approach.

Broader Context

FSIS has been publicly focused on enhancing its Listeria oversight process since late 2024. Expanding the environmental sampling pilot marks a significant step in FSIS’s efforts to gain more real-time information about plant conditions.

The program expands FSIS’s visibility into conditions within RTE processing environments by providing more regular sample results. Historically, environmental samples have been collected as part of specialized sampling activities, typically conducted by Enforcement, Investigations, and Analysis Officers (EIAOs) at irregular intervals. Under this new program, in-plant inspectors will collect a modest number of environmental samples but at a more regular frequency. As FSIS notes, inspectors will require training in proper environmental sampling techniques.

FSIS describes the expanded sampling as a tool for identifying potential Listeria harborage sites and assessing sanitation effectiveness at individual establishments while also providing insight into Listeria trends nationwide, noting that “Broader sampling and more data ultimately means safer food.” The agency says it intends to use the resulting data to work with establishments to ensure that corrective actions effectively address root causes or harborage sites.

Establishments should be prepared for additional FSIS scrutiny in response to positive findings. Further, WGS results for Lm-positive samples could show possible connections to illness clusters, past samples, or other points in the supply chain.

Next Steps

Companies producing RTE products under FSIS jurisdiction should take steps to prepare for the increased sampling, such as:

• Evaluating the establishment’s environmental monitoring program and historical findings;
• Assessing corrective action and root cause investigation practices and capabilities;
• Conducting any desired program updates or self-evaluations before enhanced sampling is implemented; and
• Ensuring the company has the ability understand and assess WGS results.

We will continue to monitor this program and other developments related to Listeria control. Please do not hesitate to contact us if you have any questions.