Access flooding information on Disaster Resources.

November 2, 2019

Food Safety – Let’s Take a Step Back

In a recent article, I talked about Western Growers’ leadership in the food safety arena. For decades now, Western Growers has been the leader in what has been the single largest shift in food safety culture for growers and handlers on record. We have worked hand-in-glove with our members to design and consistently enhance preventive controls in the field as the first line of defense in food safety. Our member companies, steadfastly committed to providing the safest, highest quality produce in the world, have quietly and diligently worked to create a food safety paradigm that has now spread beyond the West and beyond those few commodities-of-concern to the entire produce industry. The Produce Safety Rule—which affects (almost) all suppliers both foreign and domestic—incorporates much of the seminal work that we, as a Western industry, have labored over for the last decade. We truly have made a difference.

Despite that very productive work, foodborne illness outbreaks continue to occur. Now is not the time to grow weary, but to think through and act on what more we can do and what we can do better. While others are recommending unrealistic deadlines and questionable priorities for the leafy greens industry—recommendations I believe set the Leafy Greens Marketing Agreements up for failure. I think our next smartest course of action is to take a step back and work directly with Western Growers to aggregate food safety data to inform our next steps. Let me explain.

What has been talked about for quite some time now in food safety circles is the need for quantitative risk assessments (QRA) that can truly make an impact—using real-world experience, data, and costs of key food safety interventions—on public health. Analyzing risk is very consistent with the grower/handler mentality. There are many hazards associated with growing fresh produce outdoors in a largely uncontrollable environment, and industry astutely wants to know which of those hazards are the most important, which translate to the highest risk, and if you have a dollar to spend on food safety interventions, where is that dollar best spent?

I don’t think we can sit here today with the data that we currently have and say the next best investment is in the development of controls for furrow irrigation systems. It is time to put industry and agency data to work for the benefit of all. We need to take the qualitative risk assessment work that has been guiding us for the last decade and move to a formal quantitative risk assessment process. Growers and handlers deserve to better understand where their efforts and investments are best deployed. And as leaders in the food safety arena, it is incumbent upon us to help them gain that understanding.

So how do we go about this? In 2012, Drs. Rock, Gerba and Bright, a very competent team hailing from the University of Arizona (UA), showed the way with a Center for Produce Safety study entitled, “Assessment of E. coli as an indicator of microbial quality for irrigation water use for produce.” While the first phase of this study looked at comparing methods for detecting E. coli in irrigation water as well as factors that might influence false positives, the second phase was about evaluating the risks associated with varying irrigation methods.

Specifically, Dr. Rock’s team set out to: 1) develop an exposure scenario (model) for E. coli in irrigation waters; 2) estimate the risk of illness from ingestion of various levels of E. coli from varying irrigation scenarios; 3) develop a simple, user-friendly guideline for estimating risk of infection from the different irrigation scenarios; and 4) compare their results to risks associated with current standards (at the time 126 CFU/100 mL).

This is a quantitative risk assessment—and specifically a Quantitative Microbial Risk Assessment (QMRA). QMRA is a data-driven process that estimates the risk of infection and/or illness from a pathogenic microorganism. Indeed, the UA team’s QMRA results showed a decreasing level of risk for overhead, furrow and drip irrigation (in that order), but as outstanding and important as it was, their work only looked at irrigation water and only used data from the Yuma region.

QMRA is typically used to estimate the risk from the ingestion of a known pathogen by water or food. The UA team’s QMRA factored in the number of pathogenic E. coli in water, the amount transferred to produce, and E. coli survival rates on the crop (both pre- and post-harvest) to estimate the number of E. coli ingested by a consumer eating a typical serving. This information coupled with infective dose was then used to calculate the probability of illness. Granted, there is some uncertainty embedded in all QMRA models—but it is, to date, one of the more interesting studies that provides a focused look at food safety hazards associated with the routine production of fresh produce. More studies like this need to be conducted in other regions on other types of food safety hazards.

Imagine if we understood the varying risks of hazards related to soil amendments or the proximity to different types and sizes of animal operations in terms of “probability of illness.” We could then begin to look at these risks in total and assign our efforts and interventions to areas having the most significant positive impact on public health. Instead of spending time, energy and money on every risk under the sun, we could focus on the areas having the highest probability of illness and, therefore, have a more meaningful impact on public health.

These types of studies are only possible with robust data sets. The data collected by industry presents a great opportunity to understand and evaluate hazards and risks more completely. Through better understanding, we can target controls to areas of highest impact, and save both time and money for industry as well as potentially reduce the number of foodborne illness outbreaks. Unfortunately, the data mostly resides within the walls of the discrete companies that collect it, which is why Western Growers has made it a priority to push for our member companies to share data with us so we can facilitate broader industry learning and improvement. For nearly a century, Western Growers has been a trusted grower and handler representative and though some folks may have reservations sharing this type of information, we have a history of protecting individual member data and information while putting it to its highest use in academic, regulatory and industry circles.

Today, I am calling on Western Growers members to share with us their food safety data in order to empower the industry to make meaningful changes to food safety programs. It is only through an engaged membership that we will continue to make progress for our members. The time is now to harness and analyze decades’ worth of data to more effectively improve food safety systems rather than heaping new, unexamined controls on growers without the confidence that they will indeed reduce illness.

Western Growers members, across the board, have implemented the strongest preventive controls to date. These controls undoubtedly make a difference and have become the foundation for fresh produce food safety throughout the world. That said, we must embrace the use of quantitative data analysis to continue to evaluate where we are and how we can deploy the most effective controls rather than just reacting to outside recommendations based on anecdotal evidence.