Monday, March 5, 2012

Produce Farming on the Brink

by Daniel B. Cohen | Mar 05, 2012

Our process of framing and regulating produce food safety is upside down and backwards.

Human pathogens constantly flow from urban environments and animal production into farm environments, contaminating water and soil, and finding a home in wildlife. Then we ask farmers to deliver pathogen-free fruits and vegetables.

Produce is increasingly sold as centrally processed fresh-cut products, diced fruits and cut salads in wholesale and retail packages, facilitating cross-contamination without a kill step. Then it is shipped in closed plastic containers that can allow pathogen maintenance and growth, with use-by dates of about three weeks from harvest. A cold chain for processing and delivery, that prevents E. coli O157:H7, for example, from multiplying allows Listeria to survive or thrive.

On farm, two of the greatest hazards have nothing to do with actually growing the crop. Washing, cooling and storage -- on-farm handling, and providing sanitary conditions for employees that do not lead to human-to-produce contamination. On farm regulation focuses on field practices.

Farmers are asked to cut down trees and shrubs, which provide habitat for birds; to fence off fields and water sources, which might attract deer and other large species; to bury poisoned bait stations around the perimeters of their field, to prevent squirrels, mice, shrews and other rodents from entering their fields; to remove the low-growing filter strips next to streams, which actually prevent fertilizer run-off and some pathogens from entering the streams, because they also attract wildlife.

They are supposed to have management practices that prevent flies and other insects, snails and other invertebrates, frogs and other amphibians, from carrying human pathogens onto their fields. All have been shown to be potential carriers. Since farm food safety is focused on growing operations, sources that provide human pathogens to contaminate the fauna of a farm ecosystem are not regulated.

I use produce outbreaks where there have been outbreak investigation reports as case studies that provide some, limited, evidence. They may or may not support this thesis. They provide a window into how produce safety is being framed and understood.

In this article two of the 2011 outbreaks are covered: the Jensen Farm Listeria-cantaloupe outbreak and the Jaquith Farms O157:H7 strawberry outbreak. The implications for food safety policy are covered on the national and then small-farm scales.

Using the normal rules of thumb that make sense of food safety, there should never have been a Jensen Farms lLsteria cantaloupe outbreak. We may be in a changed world.

The FDA environmental assessment Report (1) states:

"This is the first listeriosis outbreak associated with a whole fruit or vegetable raw agri- cultural commodity. Listeria monocytogenes contamination has historically been associ- ated with ready-to-eat and processed food products, such as deli meat, unpasteurized cheese, raw milk, fresh-cut fruit, and fresh-cut vegetables, and is typically thought of as an environmental contaminant of food plants. Known reservoirs for Listeria monocytogenes include ruminant animals (e.g., cattle, goats, and deer), decaying vegetation, and cold, wet, and difficult to clean environments."

Fresh-cut fruits and fresh-cut vegetables are recent food additions to the list. The usual combination of concern is Salmonella and cantaloupes, not Listeria,

With 33 deaths out of 146 reported cases, the Listeria-cantaloupe outbreak was one of the worst foodborne outbreaks in over 80 years. The death rate is close to 25 percent.

In many outbreak investigation reports I have read, "absence of evidence" in a processing facility is taken to be "evidence of absence," even when it was documented that management had spent up to a week sanitizing their plant post-outbreak and pre-inspection.

In the Jensen Farms case, the equipment design and facility design prevented sanitation, both before the outbreak and before the investigation. Outbreak strains were found within the packing facility and cold storage. It was a rare case of presence of evidence, and some equipment had to actually be cut out and replaced in order to be sanitized to show no Listeria.

When the FDA looked for a source of contamination on-farm, they took the more usual approach.

"All environmental samples collected in the growing fields were negative for Listeria monocytogenes."

Despite this:

"FDA has determined that the growing environment cannot be eliminated as a potential
contributor in the introduction of Listeria monocytogenes contamination..."

That is true, as far as it goes, but it is also true of pretty much every farm in the country, given the ubiquity of ruminants and of Listeria in the environment. It does not do much to explain the origins or root cause of this unique case (2).

Many observers, including Bill Marler, have characterized the on-farm handling as gross negligence; and condemned the lack of prevention by food safety auditors. Jensen Farms had passed its audits for safety. Its papers were in order.

Now Jensen Farms appeared to me to be a large or very large operation responsible for a national outbreak centered on Colorado and Texas. Based on the recalled canta-Jim loupes alone, it looked like it probably was one of the 5,600 largest farms in the country with farm gate sales of over $5 million.

Jim Prevor had outstanding coverage of the outbreak in his Perishable Pundit articles but with a very different perspective (3):

"If Wal-Mart really put food safety first, it would have never bought cantaloupes from this small producer, which produced in a six-week season what California ships in a day."

A small farm with local production, and small farms are not safe? We do not seem to be talking about the same outbreak. When I asked him about this, it turned out we were using the same words with different meanings from different contexts (4).

Prevor's context is the national produce market, dominated by the largest buyers and their major produce suppliers. The vocabulary of the buyers is different than farmers, and perhaps most of their customers. "Local" can be defined as "within a 7 hour drive" by Whole Foods. "Small" in this world of the top strata within the top 5,600 farmers (the number is for all crops, not just produce) includes Jensen Farms. He estimated that maybe 10 of the very large melon farms in the U.S. had the money, size and motivation for a particular kind of food-safety processing equipment.

His main point was that the largest buyers do not make food safety their first priority in buying decisions, when one looks at how they actually operate. For example, if they can label produce as "local," in their terms, this can have top priority. Buying from a "small" farm like Jensen Farms may meet a marketing decision for "local" produce, despite there being major farms with better food safety capacity. Therefore "safe versus local" as a choice. He was using the words as industry terms; to people outside the industry, they read differently.

Prevor then makes a critical observation: that how major produce buyers are actually rewarded determines the effectiveness of food safety commitments. He wrote an interesting analysis of overall food safety issues, including changing liability so that food safety is not unrewarded (5). On a national policy level his approach and mine have many points in common. Trying to use common language:

The food system as a whole should be evaluated by a hazard analysis. The worst hazards overall should have the highest priority for being dealt with.

To really have an effective outbreak, one has to have a way to spread and multiply the pathogens; incidental contamination won't do the job.

Any centralized source for contaminating produce, which spreads, multiplies, and preserves pathogens is more dangerous than any incidental source. Handling and processing can be major centralized sources in handling, and fresh-cut is a special hazard in part because it is food processing without a kill step.

Widespread hazards from the farm environment also can create broadly contaminated produce, for example from contaminated surface water or ground water or flooding.

Within farming operations, handling operations, packing and cold storage as in Jensen Farms, might be the highest priority after water quality and direct exposure to feces. Texas may be the state that has gotten this right, with a new law focused on on-farm handling (and processing).

Incentives for individual decision makers also can determine over-all food safety. Company incentives for major buyers are also a critical control point for food safety. Business expansion and growth with increased contracted deliveries can be a hazard for two reasons: newly acquired equipment can be a hazard, and pressure to deliver can lead to pressure on safety standards (6).

However, right now, we are quite distant from this approach.

On October 06, 2006, as the spinach outbreak was ending, the FDA put out one of the bluntest statements issued by a bureaucracy, saying to the lettuce and spinach industry that enough was enough, clean up your act or we will do it for you; and inadvertently creating the category of "leafy greens" (7).

In my view, what happened next was a tactically brilliant takeover by the major processors and handlers of the produce safety issue, starting with the California LGMA. It left farmers under the control of processors, who somehow left out the food safety issues of handling and processing operations.

The fundamental flaw in this approach is that in the absence of an effective kill step, for fresh-cut in particular, they basically have to sterilize the farm environment instead, which is impossible. It can be an ecological, social and strategic disaster. [For detailed discussions of the impact on farm environments see the Wild Farm Alliance website (8).]
This "processor-favoring" approach dominates all discussions of food safety on farms.

A cold-hearted analysis of sprouts as a commodity, that takes food safety as the first priority, is that they should be cooked. A cold-hearted analysis of fresh-cut as a commodity is that it is a food safety failure. We could go back to local production consumed within a few days of harvest for salad greens; local food service doing their own cutting for "fresh-cut" fruits and vegetables. This eliminates the pathogen increase time from farm to retail to consumption, and other factors. As commodities, both sprouts and fresh-cut lack kill steps and provide humid sealed environments in plastic containers for pathogen maintenance and increase.

Food safety, looked at cold-heartedly, is not the top priority when fresh-cut processing is analyzed. Other factors, including market share, value-added, and consumer convenience are priorities. Priorities have to be balanced, perhaps. It is not a justification for displacing all food safety concerns onto farms.

That still leaves the whole produce outbreaks.

It's curious. No one studies the effectiveness of small farms at achieving food safety. I once heard an FDA hearing commissioner explain to an audience of mainly large processors and grower-shippers: "what you call a spinach harvester, I call a pathogen inoculator." Harvesting on small farms is completely different, but which techniques are better or worse for food safety in comparison?

Can small farms really have a better safety record, and if so why; due to which practices?

The 2011 E. coli O157:H7 outbreak in Oregon involving Jaquith Strawberry Farm, initially thought to be a small grower, looks like a fairly large producer, distributing through multiple channels. One of them, Ron Spada Farms, was reported to have recalled 4,800 flats still in inventory after the outbreak trace-back. Other strawberries went to roadside stands, farm stands and farmers markets as if they were self-produced (9).

This can make "knowing your farmer" problematic. The farmer wasn't small, and the people who looked like small farmers weren't farmers, or had not grown the crop. Consumers may have had the illusion they were buying from a small local farmers in many parts of Oregon. Only the epidemiological trace-back found the common source.

There was no complete outbreak investigation report, but the outbreak strain was found in deer feces in the actual sole-farm's strawberry production field. If there is a widespread pathogen contamination of deer, it did not affect multiple producers.

UC Davis field studies showed that O157:H7 in deer in California was quite rare, challenging the frequently made association with some California outbreaks. Oregon might be different.

There are many actual small strawberry producers in Oregon. They all managed to avoid causing outbreaks. There also are very large producers (super-farms) including Driscoll's, which appears to have an outstanding food safety record, who also grew and sold strawberries safely.

It looks like this outbreak could have been due to negligence, probably at harvest, on one "medium" sized farm; that ordinary precautions might have been enough to prevent contamination even with the presence of E. coli O157:H7 in local deer.

Is there a statistical distribution of food safety by farm size? We know that the pressure of growth can be a major hazard point, throughout the produce outbreak record. Food safety can slip under the pressure to meet increased sales.

Actual incentives are not just a hazard point for the largest national produce buyers; they can compromise safety priorities for individuals or operations anywhere in the supply chain.

This outbreak involved multiple illnesses and one death. It was a relatively local, perhaps "regional" and "limited" outbreak. That is cold or no comfort to the family of the person who died or to those who became ill.

One can imagine a consensus on a set of national priorities focused on fixing the worst hazards first, an FDA that puts more emphasis on causal analysis of outbreaks as Michael Taylor has called for, and co-management of food safety and the preservation of habitats and the farm environment, as both the California LGMA and the Wild Farm Alliance have called for. Overall food safety would be greatly improved.

That is not where we are, right now.

What can I say to a small organic farmer who asked me about the impact of the three major outbreaks in 2011, and the oncoming regulations under the Food Safety Modernization Act (FSMA)?

By acreage, she and her husband are small farmers under any U.S. definition, owning and farming 20 acres. By farm gate sales they are in the top 20 percent of U.S. farmers.

Something like this:

Most of the work being done on food safety is not for their benefit and the regulatory schemes in process may be mostly harmful, imposing burdens without improving overall food safety because it avoids dealing with major hazards in the overall system of food production.

Regulators have a compulsive belief in the efficacy of complex paperwork, almost for its own sake. It could be called faith-based paperwork. The same money could be spent on solving problems, but they assume the solutions are all known.

In contrast, they should try and align their ordinary commercial records with food safety, an approach also favored by some major food safety consultants for the largest firms.

They need to know how to approach a recall, and be able to trace-up deliveries quickly.
Regulation will be based on the largest farms, even when these have been the source of multiple recalls or even outbreaks. Systemic failures such as the Listeria-cantaloupe case will not lead to new systemic approaches.

Expect to pay for third-party audits that lack meaning; and Extension services, which might have been helpful in actually solving safety problems, have been cut in half.

Reduce known hazards. There may be some crops, and some ways of growing and harvesting crops, that have to be dropped. Look carefully at washing, handling and packing.

Make food safety an over-riding contingency of sale in delivery contracts. Make food safety a part of any plan to grow production and sales, from the start. Consider increasing liability insurance and buying business interruption insurance.

Improved safety, and meeting all imposed regulations, provides no legal protections. In- cidental contamination beyond farmer control still comes under strict liability.

They can improve their odds.

I can guess that the ethical standards they use in all their approaches to farming do have a beneficial impact on food safety as well, for their size of farm, because they frame their own personal incentives, and oppose temptations to cut safety to meet a dellivery.

"Don't screw up." Know the common important hazards and have a systematic plan to control their risks.

You are always,farming on the brink of disaster.

(1) Environmental Assessment: Factors Potentially Contributing to the Contamination of Fresh Whole Cantaloupe Implicated in a Multi-State Outbreak of Listeriosis
October 19, 2011

(2) A lot of specific information is missing from the report that could be useful in analyzing the outbreak and preventing future outbreaks. Jensen Farms used equipment that could not be cleaned, that came from a non-cantaloupe use (supposedly for potatoes). Was the previous operation contaminated with the outbreak strains? Similarly, a truck was used to bring culls to a cattle operation as feed and could have been a contaminant source for the cleaning and packing facility. Were outbreak strains found in the cattle operation? A neighboring field was reported to have received municipal sewage sludge, of unreported treatment, and Listeria bacteria are resistant to degradation in sludge. It would be important to know if the outbreak strains were found in the neighboring field.

I read " All environmental samples collected in the growing fields were negative..." in a lawyerly fashion, and wonder why environmental samples collected in the larger environment were not reported on.

For a comprehensive review of Listeria and food safety and Listeria in the agricultural environment see, for example: Listeria, Listeriosis, and Food Safety, Third Edition
Edited by: Elliot T. Ryser, Michigan State University, East Lansing, USA; Elmer H. Marth, University of Wisconsin, Madison, USA March 27, 2007 CRC Press

(6) For example, that is my reading of the outbreak reports for two major cases: Odwalla juice, and Dole spinach, as well as others.

See "Next Steps" section.

(9) Deer Confirmed as Source of Strawberry Outbreak  August 18, 2011, Food Safety News


Daniel B. Cohen is the owner of Maccabee Seed Co., an agricultural research-and-development and consulting company in Davis, CA. See also "Sizing Food Safety Regulations to Fit the Farm" and "An Outbreak Like Germany's Could Happen Here"

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