FDA says more research needed on listeria presence on ready to eat produce

Mickey Parish (from left), senior advisor for microbiology in the Office of Food Safety, Center for Food Safety &; Applied Nutrition, FDA; Mike Mahovic, consumer safety officer at FDA; and Donald Kautter, senior advisor/consumer safety officer at FDA, listen to Samir Assar, director of the division of produce safety in the FDA during a panel session at the United Fresh Washington Conference. Jennifer McEntire, vice president of food safety and technology for United Fresh, and Drew McDonald, vice president of quality and food safety for Salinas, Calif.-based Church Brothers Farms and True Leaf Farms, moderated the session.

COLLEGE PARK, Md. — Both industry food safety leaders and Food and Drug Administration produce safety staff say more research is needed on the levels of Listeria monocytogenes found naturally occurring on ready to eat produce coming into packinghouses.

The need for further research on Listeria monocytogenes on produce coming into packinghouses, as well as what operators can do to reduce the threat of outbreaks linked to Listeria monocytogenes, was a key topic discussed during a 50-minute meeting Sept. 20 that was part of the United Fresh Produce Association Washington Conference agenda.

The session was moderated by Jennifer McEntire, vice president of food safety and technology for United Fresh, and Drew McDonald, vice president of quality and food safety for Salinas, Calif.-based Church Brothers and True Leaf.

FDA officials represented at the meeting included Samir Assar, director of the division of produce safety at FDA, Mickey Parish, senior advisor for microbiology, Mike Mahovic, chief of the Fresh Produce Branch in FDA’s division of produce safety, and Donald Kautter, consumer safety officer at FDA.

Some of the questions at the event related to preventive controls rule inspections, including how FDA makes inspection assignments.

Other queries touched on FDA expectations for the Foreign Supplier Verification Program and compliance with supply chain control regulations.


Listeria focus

McEntire asked FDA officials about the presence of listeria in produce packinghouses and on products coming from the field.

Regardless of whether packinghouses are regulated under the preventive control rule or the produce safety rule, she said much of fresh produce is ready to eat but has no kill step to eliminate pathogens like listeria.

“We know that listeria will be found in packinghouses and on product because (commodities) grow outside,” she said.

She said the FDA’s policy and the Food Drug and Cosmetic Act has a zero tolerance for Listeria monocytogenes. Given that reality, McEntire asked, “What does the FDA recommend to the produce industry in terms of what we can do to achieve zero risk of Listeria monocytogenes on a product, since any level or frequency will make the product adulterated?”

Parish of the FDA responded with an answer that ultimately called for more research on listeria levels for produce coming from the field.

“This is a difficult question and we have been trying to address listeria in ready to eat foods since the early 2000s,” he said. He noted the FDA in January issued a draft guidance document for firms that fall under the preventive controls rule, and the agency is reviewing those comments.

That document, for facilities under the preventive controls rule, recommends steps to control listeria within those facilities. At the same time, Parish said listeria must also be scrutinized at packinghouses for whole produce as well.

“When it comes to packinghouses specifically, we can point to at least three outbreaks that occurred in recent years where it appears as though the packinghouse was potentially the source of the organism,” he said. 

He said that packinghouses should attempt to establish some listeria control procedures that would be helpful in ensuring that the packinghouse itself is not contributing to any contaminant levels,” he said.

He acknowledged that approach is a “paradigm shift” in terms of how the industry thinks about listeria compared with years ago.

“Now we see that packinghouses themselves may indeed be potentially contributing to outbreaks that occur,” he said. “We would suggest that it is appropriate to look at methods to control it.”

As far as natural contamination of produce from the field, Parish said that the agency knows that occurs but doesn’t have any hard data about what levels of listeria are found on produce coming from the field.

“What data we have thus far suggests that it is a small amount, probably not that frequently for those produce items we would think of as being ready to eat,” he said. Parish said having hard data on the presence of listeria found on produce coming from the field would be helpful to the agency, stating that if United Fresh worked toward collecting that data, the agency would love to see it and consider it when making decisions on how to guide the industry.

In fact, McEntire replied that the Center for Produce Safety has just issued a request for proposals that includes a request for research on natural levels of contamination found on produce.

“We all recognize that a packinghouse as a source of Listeria monocytogenes is unacceptable and I think the industry is working toward solutions that address that,” she said. “There is still the underlying concern about the natural, and seemingly unavoidable, low frequency (listeria levels) that we may not be able to detect illness associated with, but is still considered an adulterated product,” she aid.

McEntire said the industry is working on expanding research about listeria levels found on produce and looks forward to providing that data to the agency to consider.


Input welcome

McEntire said the format of the meeting with FDA allowed a focus on key concerns.

“Members got to see the faces behind the policies that impact them and get answers to their questions.”

Assar said the agency welcomes industry input and questions.

“We have been going out quite a bit to connect with the industry and it is really one of the main themes of the Food Safety Modernization Act — strengthening our partnerships with the industry and other partners as well,” he said. “It is important for us to stay connected and get the feedback. It really drives what we do,” he said, noting the agency’s recent announcements helped address industry concerns about water testing requirements in the produce safety rule. 

Among other steps, the agency is extending deadlines for compliance to water testing regulations. The FDA has delayed inspections for the produce safety rule for a year.

“We will certainly have bumps on the way, but we are absolutely committed to getting it right and we welcome your feedback,” Assar said.

Mahovic highlighted the role of the Produce Safety Network in helping the FDA understand produce growing operations in all parts of the U.S. 

He said the FDA has seven subject matter experts on produce safety in the field and plans to add another. The officials will work with industry and become familiar with commodities and their unique growing characteristics in different parts of the U.S.