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  • Writer's pictureJennifer

A shotgun approach to regulatory sampling: Collard Greens and Listeriosis

When you think of foods likely to cause listeriosis, collard greens are unlikely at the top of the list. And although past performance is no guarantee of future results, my initial reaction on seeing the recent recall of bagged collard greens due to the presence of Listeria monocytogenes was “is this our greatest risk”?

The recall was triggered by test results from a state laboratory. Unless I am missing some other trigger, it seems that choosing collard greens out of all food items and all produce items shows a lack of risk based testing, and a poor use of resources.

To be clear, I am not suggesting that L. monocytogenes in any food is a good thing. It is not to be encouraged. Having done my doctoral research on this pathogen, and later working with the produce industry to develop meaningful Listeria environmental monitoring guidance and training for hundreds of industry members, please don’t misinterpret this post as condoning L. monocytogenes in food. Sanitation and hygienic design should be top of mind in any production facility, whether the food product is considered ready to eat or not.

But in this case, it is hard to understand why a state regulatory agency would choose to test collards for L. monocytogenes. Unless there is more to the story, such as concerns revealed during an inspection or a history of the pathogen in other products coming from this supplier, this seems like a misallocation of testing resources.

Collards are not a ready to eat food. Yes they are green, and yes they are leaves, and perhaps there is small minority that likes to eat them raw (I did see some recipes online, but most included a vinegar based marinade to soften them up). As a category, they are listed by FDA as a food that is “rarely consumed raw”. If you’ve ever prepared collard greens, you’ve probably cooked them for a long time—longer than most other cooked greens. Listeria would not survive.

L. monocytogenes is a hazard, but when present in a cooked product the risk (likelihood of causing illness) is very low. So why, of all the foods out there, would a state department of agriculture choose a bag of collards? I suspect the issue boils down to (pun intended) a few cascading issues:

1. The source of funding. I wonder if the funding that supports this testing facilitates a lack of prioritization. States can do testing on their own, and over the past few years many states, including Tennessee, have participated in FDA’s “Laboratory Flexible Funding Model”, ostensibly to help build laboratory capacity. Initially, there was little publicly available details on this clandestine program, which seems in part to replace the de-funded USDA pathogen testing program from years ago. Thankfully, a couple of months ago FDA published a summary of the year 2 results showing the pathogens and products of interest. States work with FDA to develop a plan for items they intend to test. Who knows if this testing was part of that program, and if it was, if the plan was to test collards (hopefully not) or to test “leafy greens” which is listed as a commodity.

2. If the state chose to test collards because they are a form of “leafy greens”, oh my. We know that most Americans don’t consume sufficient quantities of vegetables. Is the state of produce knowledge such that people don’t know what collards are or how to prepare them? Could the state representative truly have thought that this was something you’d throw in a salad, similar to romaine or spinach? If so, additional training and education are needed so that people can distinguish between different types of leafy greens.

3. It’s possible that the person who selected collard greens for testing was aware of the typical preparation of this vegetable, and maybe that it even qualifies as “rarely consumed raw”. In this case, testing collards could be a consequence of not distinguishing between a hazard and a risk.

An important point is that the firm recalled the product, and recalls are typically voluntary and initiated by the producing firm. This means that, in theory, the firm could have pushed back and refused to recall the product on the grounds that it is not a ready to eat food. (bonus points for anyone who knows a firm that’s done this, including when the product was linked to illness, which is not the case with the collard greens). I’ve observed that firms seldom push back against regulators, even when it is justified. Even if there is limited public health risk, a company may fear reputational risk if there is a perception that they don’t care, or they may be concerned about regulatory risk (now or in the future) if they don’t do what the regulator asks.

In seeing the press around this recall, my main concern is that it serves as a distraction. The public health risk in this instance is low. There are plenty of other issues that can legitimately cause harm and deserve attention, both from regulators and from industry. Resources (time, money, technology, testing, etc.) should be allocated to best serve public health. A shotgun approach to food safety is probably going to miss a lot. In the case of collard greens and Listeria, even the hit was a miss, in my opinion.

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