LGMA: What’s behind the preharvest testing of leafy greens

As a candidate to become the new CEO of the California Leafy Greens Marketing Agreement, I was clear in interviews with board members that I was only interested in the job if they were serious about taking real action to prevent future outbreaks. Without hesitation, board members assured me they were.

Fast forward six months into my employment with the California Leafy Greens Marketing Agreement (LGMA), and exactly what the board promised has happened. At its last meeting, the LGMA Board voted unanimously to require its members to conduct preharvest testing of product grown in fields where elevated risk factors may be present. I’m not sure if people realize what a significant action this is when it comes to leafy greens safety and what a tremendous commitment it is for lettuce farmers. That’s why I’m taking the opportunity here to explain exactly what this requirement will entail.

First, and foremost, everyone needs to understand the LGMA food safety program already includes restrictions that don’t allow leafy greens to be planted in areas of high risk. The program has minimum buffer zones in place for areas in the proximity of animals. For example, under the California LGMA, leafy greens cannot be planted within a mile of a large Concentrated Animal Feed Operation or CAFO.

New preharvest testing requirements now being added by the LGMA program are designed to verify existing requirements are working and to ensure that extra precautions are being taken if there is even a suspicion that risk may be elevated in a particular field.

Specifics of the new preharvest testing requirements are still being finalized. But the LGMA Board action now makes this testing a universal requirement with standardized protocols, and it will be verified as part of the LGMA’s government audits.

When the details are officially adopted, they will require that LGMA members conduct a risk assessment for each field in which they plan to grow leafy greens. Guidelines for determining the risk status of a field are being finalized now. A partial list can be found here.

If the assessment shows elevated risk factors are present, the product grown in that field must be tested for pathogens four to seven days before it can be harvested. Protocols for a standardized sampling and testing methodology are currently being finalized through a process coordinated by Western Growers. This process is extremely thorough and involves a team of food safety experts who are fully vetting the methodology to ensure lettuce farmers are using the best science available.

In summary, the protocol mandates that several random product samples must be collected throughout the field. These samples will need to meet a minimum weight per acre. Each sample will be tested for the presence of Shiga Toxin-Produce E.coli (STEC) and Salmonella enterica. Growers will be marking and recording where in the field individual samples were collected. This is required because if any test comes back positive for a pathogen, growers are required to do two things:

1. They cannot harvest product in that area; and
2. They must conduct what’s called a root cause analysis to determine how that area of the field may have been contaminated.

Both requirements are extremely important. Obviously, we don’t want to harvest any product that may be contaminated and the testing protocol is designed to help keep pathogens from entering market channels. But the requirement for conducting root cause analysis may be even more important. If we truly want to prevent future outbreaks, we need more information about how contamination is happening. A root cause analysis can help identify fundamental systemic issues and failures and can help prevent recurrence of these issues. Over time, the industry’s data can be used to further improve the LGMA program requirements.

It’s fair to point out that many LGMA members are already doing preharvest testing. In a recent survey, 90% of LGMA members report they are conducting pre-harvest testing on a regular basis. But the LGMA Board action now makes this testing a universal requirement and it will be verified as part of the LGMA’s government audits.

Fortunately, our efforts are being recognized. I’m pleased to report the Canadian Food Inspection Agency (CFIA) has recently announced it will be considering the LGMA’s new preharvest testing requirement as a condition for importing lettuce and leafy greens into Canada if sufficient documentation can be provided. If approved, this action could be an option to replace the finished product testing requirement issued by CFIA last year which was extremely onerous. We’re very hopeful that U.S. retail and foodservice operations will follow suit.

We say this all the time – LGMA members are committed to food safety. These preharvest testing and the accompanying root cause analysis requirements are real evidence of that. And I couldn’t be prouder to be associated with an organization going to these lengths to prevent foodborne illness outbreaks.

— Tim York, CEO, California Leafy Greens Marketing Agreement