FDA’s Warning Shot For Leafy Greens

By Michael Taylor

April 8, 2021

OPINION

View fullsize

On April 6, the Food and Drug Administration fired an unmistakable warning shot at the leafy greens industry. I hope it will serve as a call to urgent action that gets to the root of the problem of the persistent presence of dangerous E. coli in the growing environment for leafy greens and other fresh produce.   

Carefully using the regulatory language in its produce safety rule (21 CFR 112.11) and citing the recurring nature of the E. coli hazard in the Salinas and Santa Maria growing area, FDA declared the recurring strain implicated in the 2020 outbreak to be a “reasonably foreseeable hazard,” which FDA attributed to the presence of cattle on land adjacent to growing fields. 

This finding seems obvious and shouldn’t be surprising. The surprise, however, is that FDA used regulatory language to express its finding and spelled out the implications: farms covered by the FSMA produce safety rules “are required to implement science and risk-based preventive measures” to minimize the risk of serious illness or death from the E. coli hazard.  

Make no mistake, however, FDA’s message is aimed not only at farms but at every entity involved in the commercial production, processing, and sale of leafy greens coming from the California Central Coast Growing Region.  The message is that, without effective preventive measures, such leafy greens are in violation of federal food safety regulatory standards. 

I do not anticipate FDA taking judicial action to enforce its April 6 finding, absent egregious practices or clear negligence in a particular leafy green growing situation. I do see, however, a heightened sense of urgency at FDA and frustration that efforts to date have not solved the leafy greens safety problem. I share that frustration.  

Fifteen years ago, the disastrous spinach outbreak caused by E. coli O157:H7 was linked by the Centers for Disease Control and Prevention (CDC) to run-off from nearby grazing land. Since then, we’ve had outbreak after outbreak associated with E. coli in leafy greens and other fresh produce. And the outbreaks are just the tip of the public health iceberg.  The federal government estimates that 60 percent of all food-related E. coli O157:H7 illnesses are associated with fresh produce. The vast majority of these illnesses are not part of an identified outbreak.

The E. coli outbreaks and illnesses persist despite a lot of hard work by a lot of people in the leafy greens industry, researchers, the California Department of Food and Agriculture (CDFA), the FDA and its federal partners.  Stop Foodborne Illness, the organization of illness victims and their families whose board I co-chair, works with the California LGMA on the common cause of strengthening food safety culture in the leafy green industry. We also advise the Leafy Greens Safety Coalition, a group of leading retailers working to strengthen safety practices.  I have participated in the California Agricultural Neighbors Workgroup convened by CDFA Secretary Karen Ross. So, I know serious people are at work on the problem.

What then is the urgent call to action?  What do consumers expect of the leafy greens industry, especially those individuals and families who know first-hand the devastating human impact E. coli infections can have?  What does the public health demand?  

At one level, the answer to all three questions is the same. The leafy greens industry and all those across the leafy greens supply chain and in government should be doing urgently everything they reasonably can to minimize the now well-known risk posed by E. coli O157:H7.  According to FDA, the law requires no less. Certainly, this includes prevention measures within the leafy greens production system, such as strict implementation of rigorous water quality and irrigation standards, improved compost management, sanitation of harvesting equipment, and pre-harvest test-and-hold programs.  

But the prevention strategy must go deeper. Modern food safety best practices dictate that prevention should begin at the root of the problem.  As long as leafy greens are grown outdoors in the vicinity of cattle operations, I believe the food safety problem will persist until the shedding by cattle and the release of dangerous E. coli into the environment is minimized at its source. Effective vaccines are available. Changed feeding practices have promise. Perhaps containment measures can reduce risk.  

The experts need to determine what combination of measures works best, but it is clear that no responsible food manufacturer would today deem it acceptable to produce food in an environment in which dangerous bacteria are being released or are present on a sustained basis. The same principle should apply to leafy greens and other fresh produce grown outdoors.  

The important difference, of course, is that the leafy greens producer has no direct control over the source of the hazard.  And the cattle producer isn’t responsible for where leafy greens are grown. That is why FDA Deputy Commissioner Frank Yiannas calls for “industry leadership and collaboration among growers, processors, retailers, state partners and the broader agricultural community,” including cattle producers.  

I am glad FDA is sounding the alarm, but I know from experience that the kind of leadership and collaboration that is urgently needed is easier said than done in an industry and government structure that is notoriously fragmented and often works in silos. And the obstacles to solving the problem are not just technical. They include the need for creative solutions on such matters as who pays for interventions needed in cattle production to make leafy greens safe.   

But too much is at stake for all concerned to let such obstacles stand in the way.  Now is the time for leaders from all across the commercial value chain and government to act together, with greater urgency, to get to the root of the problem and prevent it. 

View fullsize

Mike Taylor

About the author: Mike Taylor is co-chair of the board of the non-profit consumer advocacy group Stop Foodborne Illness, which is a 25-year-old group supporting and representing foodborne illness victims and their families in efforts to keep other people from getting sick. Before that Taylor served as FDA’s Deputy Commissioner for Foods and Veterinary Medicine from 2010 to mid-2016. His first tour in government began as a staff attorney at FDA, where he worked on seafood safety and nutrition labels. Later Taylor worked for USDA’s Food Safety and Inspection Service, where he became acting under secretary for food safety. Taylor was the government official who, after the deadly 1992-93 Jack in the Box hamburger outbreak, ruled that the pathogen E. coli O157:H7 is an adulterant in meat. Taylor also practiced law in the private sector.

(To sign up for a free subscription to Food Safety News, click here.)

Print:EmailTweetLikeLinkedIn

FDA: E. coli Outbreak Investigation Closes; No Specific Source Found

By CHRIS KOGER January 28, 2021

View fullsize

(Courtesy FDA)

An investigation into a fall 2020 outbreak of E. coli linked to leafy greens found cattle manure with the same strain about a mile from a field in California’s Salinas Valley, but the pathogen was not detected on any leafy greens or farms they were grown on.

The Food and Drug Administration released an update on its investigation on the outbreak on Jan. 27, and a full report will be released later. Forty people became sick in the outbreak, and half of them were hospitalized.

“Although the investigation has been unable to identify a specific type of leafy green at the heart of this outbreak, it is clear that this is yet another outbreak tied to leafy greens,” Frank Yiannas, the FDA’s deputy commissioner for food policy and response said in a news release on the agency’s findings.

Epidemiological and traceback investigations did not determine a specific leafy green, brand, or supplier, but the E. coli strain is genetically related to a strain linked to a fall 2019 outbreak from romaine lettuce.

Investigators from the FDA and other agencies visited dozens of farms in the Salinas Valley to collect samples. They also collected samples in adjacent areas, testing animal feces, compost, and water, according to the FDA. The cattle manure that yielded the positive test result was found on a roadside, uphill from where “leafy greens or other food identified on the traceback investigation were grown,” according to the FDA release.

“This finding draws our attention once again to the role that cattle grazing on agricultural lands near leafy greens fields could have on increasing the risk of produce contamination, where contamination could be spread by water, wind or other means,” Yiannas said in the release.

The FDA continues to recommend that growers assess and mitigate risks from areas adjacent to their fields, particularly in the vicinity of cattle operations, he said. That is a specific goal of the FDA’s Leafy Greens Action Plan, released in March, he said.

Yiannas said the FDA’s final report on the outbreak will include recommendations “shaped by these findings.”

Indoor Farming Industry Gets Boost From COVID-19

View fullsize

Business Industry News

January 15, 2021, Urbanagnews

By Steve Bradley

The coronavirus pandemic has caused a major shift in dining out and led many Americans to become more familiar with their kitchens than ever before. In fact, according to the 2020 “America Gets Cooking” report commissioned annually by Hunter, a food and beverage public relations and marketing communications consultant, more than half (54 percent) of Americans report they are cooking more during the pandemic. 1

Thirty-nine percent said in a survey they are trying to eat healthier, with many saying they are becoming adventurous in the kitchen, trying new ingredients, brands, and products. 1 Salads and vegetables are two of the top five food items survey respondents say they are preparing more.

This presents a tremendous opportunity for grocers to meet this demand for preparing meals at home, as well as a growing desire to maintain a healthy diet during the pandemic to assist in fighting off the unwanted pounds associated with staying at home.

Fresh produce can play a key role in eating healthy but is not something that can easily be ordered through an online retailer like non-perishable goods. Shoppers like to hold and visually inspect produce for freshness, firmness, crispness, color, and other desirable characteristics.

In short, fresh produce is a primary driver of traffic into grocery stores.

Additionally, consumers also want to know that what they are buying can be trusted. Salmonella, e-coli, and other pathogens have unfortunately made their way into our fresh produce supply, causing massive recalls, illnesses, and even deaths. Consumers want to know they are buying a safe product and – increasingly – want to know more about where it came from and how it was grown. Words like “organic,” “non-GMO” and “locally sourced,” have become part of everyday language for many Americans.

Leading indoor farming companies, like BrightFarms, offer hydroponically grown, “cleaner than organic” packaged salads that results in a higher-quality product that consumers can trust. Even produce labeled “organic” has likely been treated with chemicals such as pesticides and herbicides. This also means the consumption of water, land, and costs associated with shipping produce are dramatically reduced. Additionally, locally grown means the quality is preserved through a much shorter shipping process, while also relying on less fuel due to shorter travels to market.

Controlled-environment agriculture ensures produce is not subjected to the whims of nature, such as drought, excessive rain, or other weather patterns.

In many ways, the BrightFarms’ model of bringing local produce around the U.S. into commercial stores has the potential to disrupt the multi-billion-dollar leafy greens industry. Few people could have likely imagined 10 years ago that hailing a taxicab would no longer be the “go-to” for getting around town. Similarly, corporations, with the ability to look around corners and see the future, are re-imagining how consumers get high-quality local produce onto dining room tables.

We need to feed a growing population in a more efficient way – not tied to any one certain geographic area. Investments in cleantech-focused on resource efficiency, resiliency, and adaptation. Local, sustainable, controlled environment produce consumers can trust gives us that opportunity. We believe it is possible to make the world a better place – building a better future for the next generation – while also growing business and creating jobs.

Steve Bradley serves as vice president of Cox Cleantech at Cox Enterprises, Inc. based in Atlanta, Georgia.

GREENHOUSE VERTICAL FARM BUSINESS TECHNOLOGY CLIMATE HYDROPONICS

PLANTS EDUCATION ORGANICS

1. Hunter. (2020). SPECIAL REPORT, America Gets Cooking: The Impact of COVID-19 on American’s Food Habits. [Food Study]. Retrieved from https://bit.ly/38DIhsR

Indoor Farming Industry Gets Boost From COVID-19

By Steve Bradley

The coronavirus pandemic has caused a major shift in dining out and led many Americans to become more familiar with their kitchens than ever before. In fact, according to the 2020 “America Gets Cooking” report commissioned annually by Hunter, a food and beverage public relations and marketing communications consultant, more than half (54 percent) of Americans report they are cooking more during the pandemic.

Thirty-nine percent said in a survey they are trying to eat healthier, with many saying they are becoming adventurous in the kitchen, trying new ingredients, brands, and products. Salads and vegetables are two of the top five food items survey respondents say they are preparing more.

This presents a tremendous opportunity for grocers to meet this demand for preparing meals at home, as well as a growing desire to maintain a healthy diet during the pandemic to assist in fighting off the unwanted pounds associated with staying at home.

Fresh produce can play a key role in eating healthy but is not something that can easily be ordered through an online retailer like non-perishable goods. Shoppers like to hold and visually inspect produce for freshness, firmness, crispness, color, and other desirable characteristics.

In short, fresh produce is a primary driver of traffic into grocery stores.

Additionally, consumers also want to know that what they are buying can be trusted. Salmonella, E-coli and other pathogens have unfortunately made their way into our fresh produce supply, causing massive recalls, illnesses, and even deaths. Consumers want to know they are buying a safe product and – increasingly – want to know more about where it came from and how it was grown. Words like “organic,” “non-GMO” and “locally sourced,” have become part of everyday language for many Americans.

Leading indoor farming companies, like BrightFarms, offer hydroponically grown, “cleaner than organic” packaged salads that results in a higher-quality product that consumers can trust. Even produce labeled “organic” has likely been treated with chemicals such as pesticides and herbicides. This also means the consumption of water, land, and costs associated with shipping produce are dramatically reduced. Additionally, locally grown means the quality is preserved through a much shorter shipping process, while also relying on less fuel due to shorter travels to market.  

Controlled-environment agriculture ensures produce is not subjected to the whims of nature, such as drought, excessive rain, or other weather patterns.

In many ways, the BrightFarms’ model of bringing local produce around the U.S. into commercial stores has the potential to disrupt the multi-billion-dollar leafy greens industry. Few people could have likely imagined 10 years ago that hailing a taxicab would no longer be the “go to” for getting around town. Similarly, corporations, with the ability to look around corners and see the future, are re-imagining how consumers get high-quality local produce onto dining room tables.

We need to feed a growing population in a more efficient way – not tied to any one certain geographic area. Investments in cleantech-focused on resource efficiency, resiliency, and adaptation. Local, sustainable, controlled environment produce consumers can trust gives us that opportunity.

We believe it is possible to make the world a better place – building a better future for the next generation – while also growing business and creating jobs.

Steve Bradley serves as vice president of Cox Cleantech at Cox Enterprises, Inc. based in Atlanta, Georgia.

CDC Updates E. coli Outbreak Numbers

By CHRIS KOGER

November 25, 2020

The Centers for Disease Control and Prevention has added 16 more people to an E. coli outbreak investigation of unknown origin.

There are now 39 cases in the E. coli O157:H7 outbreak, according to a CDC notice on Nov. 23. The previous number of ill people as 16, according to the CDC. Cases have been reported in 18 states; there have been no deaths.

The CDC and Food and Drug Administration are not advising people to avoid any particular food at this time.

“State and local public health officials are interviewing ill people to determine what they ate and other exposures in the week before they got sick,” according to the CDC’s Nov. 23 update. “Of the 22 ill people interviewed to date, all reported eating a variety of leafy greens, like spinach (16), romaine lettuce (15), iceberg lettuce (12), and mixed bag lettuce (8). No single type or brand of leafy greens or other food item has been identified as the source of this outbreak. CDC is not advising people to avoid any particular food at this time.

Lead photo: (Courtesy CDC)

View fullsize

FDA Closes Investigations Into 2 E. coli Outbreaks; No Source Found

By CHRIS KOGER | December 18, 2020

Investigations into two of three E. coli outbreaks from this fall have been completed, and although the traceback process led authorities to farms, samples did not confirm link any particular food or source in either outbreak.

The Food and Drug Administration on Dec. 18 reported the investigations were completed, and the Centers for Disease Control and Prevention announced two of the three outbreaks were over. The FDA refers to the “Outbreak Unknown Source” 1, 2 and 3. Investigations into outbreaks 1 and 3 are over.

Outbreak 1

The CDC reported 32 people in 12 states became sick in Outbreak Unknown Source 1. The strain of E. coli identified in the investigation is genetically similar to a strain linked to a spring 2018 outbreak from romaine lettuce, according to the FDA. No food source was identified in the recent outbreak, however.

“FDA and state partners also conducted on-site inspections on farms of interest, though information collected in these inspections did not link these farms to the outbreak,” according to the FDA’s update.

Outbreak 3

The CDC reported 18 people in 9 states became sick in Outbreak Unknown Source 3. The FDA identified several potential food sources during interviews with people who became sick, but no farm was identified as a common source.

The FDA and state agencies conducted investigations at “farms of interest,” but information and samples collected did not lead to a source of the E. coli.

“The investigation of a farm does not mean that the farm is linked to an outbreak,” according to the FDA notice. “The results of an investigation into a farm may well lead to that firm being ruled out of the investigation.”

Outbreak 2

The investigation into Outbreak Unknown Source 2 is ongoing, according to the FDA. The CDC reports 39 cases, according to the CDC’s last update, which was Nov. 23. At that time, 22 of the people who became sick had been interviewed, with 16 reporting they ate spinach and 15 saying they ate romaine.

View fullsize

Lead photo: (Courtesy Food and Drug Administration)

E. coli Strikes Again

The World Is Scary Enough Without Our Lettuce Trying To Kill Us.

On November 10th, the CDC issued a statement alerting us that E.coli has struck again, this time in a pre-packaged single-head romaine after several people became ill from eating E. coli contaminated lettuce.

This calls us back to the past two Novembers where salad mix and commercial romaine were mass-recalled surrounding the most popular eating holiday in the US: Thanksgiving.

You might remember, the shelves all looked like this:

View fullsize

No lettuce as far as the eye can see. Photo: Washington State University

Lucky for us, the food system is slowly changing (too slowly), so that when E.coli strikes some lucky consumers can turn to small-scale indoor farmers in their area for salad greens that are not only safe, but also very tasty.

We know E. coli is bad... but what, exactly, is it?

E. coli is a bacteria found in the intestines of humans and animals.

That’s right...it’s inside of us.

Before you freak out, most strains of the bacteria are completely harmless. Unfortunately, the bad one that makes you sick (E. coli 0157:H7) is the one that’s currently in our lettuce. Womp-womp.

E. coli makes its way into the outside world… through poop. If the poop makes contact with food, you’ve got an E. coli contamination. If the poop makes contact with a lot of food, it becomes a full-on outbreak.

This isn’t just gross, it's dangerous. E. coli 0157:H7 causes intestinal infections (read: diarrhea, abdominal pain, nausea, vomiting, fever, and fatigue). In severe cases it can cause bloody diarrhea (*silent scream*), dehydration, kidney failure… even death.

This is awful. How the heck did it get on our lettuce?

The best explanation we have is animal or human poop infected the soil or water source at a big romaine farm. The scary thing is, this is only an educated guess. Since people might not start getting sick until several weeks after harvest, it’s hard to go back and try to figure out what actually happened at Ground Zero (or even where Ground Zero is).

Feel like you’re having deja-vu?

That’s because this happened literally the past two years! In 2018 we had three E. coli outbreaks in romaine alone, the worst of which was in the spring: There were reported outbreaks in 36 states with 210 infected, 96 hospitalized and 5 dead. Only months later, another outbreak struck 12 states with 43 infected and 19 hospitalized just after Thanksgiving. Since then, romaine-related Ecoli has been popping up all over the place. The most frustrating part is that it usually takes the CDC months to investigate, meaning we don’t even hear about these outbreaks until well after the dangerous food is long-forgotten.

By now you’re probably thinking…

View fullsize

Before you denounce all salad, forever, we may have a solution.

The problem is with the system as a whole.

The reason that E. coli outbreaks are so widespread is because we source 95 percent of our leafy greens from a few farms in California and Arizona. Those greens (romaine included), get harvested and amassed at big distribution points before making their way cross-country to stores and restaurants. This means zero transparency into where the E. coli originated, making it difficult to eradicate. Not to mention, a lack of regulations prevents any actual accountability. The result? We keep eating the nasty stuff, and more people get sick.

One solution is surprisingly simple… decentralization.

This problem wouldn’t exist if we moved away from a centralized food system to a distributed one with small indoor farms. Here's why:

(1) Small, indoor farms create total environmental control with all types of fancy filters and regular water tests. Plus, this prevents exposure to two common sources of E. coli: contaminated soil and animal waste.

(2) Decentralization = transparency. Lettuce from small farmers isn’t changing hands, like, a million times. In the event of an outbreak, we can easily trace it back to its source to confirm that it’s safe to eat. With a shorter supply chain, this process take days, not months.

(3) While chances of contamination in a small indoor farm are much, much, much smaller… it is theoretically possible. Distributed production means, even if you do have one contaminated small farm, the exposure is contained, so it’s still safe to eat lettuces from other local farms.

View fullsize

Cultivar Boston | Massachusetts, @chefmarydumont @cultivarboston

These are all things we know a lot of our farmers' customers appreciate about the Leafy Green Machine. Throughout this whole ordeal, they've had access to safe greens in their neighborhoods.

It’s always rattling to see how fragile our food system can be, and we hope this whole hoopla motivates policymakers, wholesalers, and shoppers to think more about how we source our food.

Want to be the change you want to see in the world?

Become a farmer

CDC Updates E. coli Outbreak Numbers

By CHRIS KOGER November 25, 2020

The Centers for Disease Control and Prevention has added 16 more people to an E. coli outbreak investigation of unknown origin.

There are now 39 cases in the E. coli O157:H7 outbreak, according to a CDC notice on Nov. 23. The previous number of ill people was 16, according to the CDC. Cases have been reported in 18 states; there have been no deaths.

The CDC and Food and Drug Administration are not advising people to avoid any particular food at this time.

“State and local public health officials are interviewing ill people to determine what they ate and other exposures in the week before they got sick,” according to the CDC’s Nov. 23 update. “Of the 22 ill people interviewed to date, all reported eating a variety of leafy greens, like spinach (16), romaine lettuce (15), iceberg lettuce (12), and mixed bag lettuce (8). No single type or brand of leafy greens or other food item has been identified as the source of this outbreak. CDC is not advising people to avoid any particular food at this time.
 

USA: Tanimura & Antle Recalls Romaine, Michigan Reports E. Coli Cases

Chris Koger

November 8, 2020

A state agency in Michigan is advising residents not to eat Tanimura & Antle brand romaine lettuce packed as single heads, and the company has issued a recall of the lettuce.

The Michigan Department of Agriculture and Rural Development on Nov. 6 issued its advisory, the same day the Salinas, Calif.-based company recalled single heads of romaine.

Random testing by the state’s agriculture department found a sample with E. coli, and more testing by the Michigan Department of Health and Human Services laboratory determined the strain is “highly related” to the strain linked to two cases being investigated in Michigan, according to a news release from the state’s agriculture department.

Tanimura and Antle’s recall covers almost 4,000 cases of single heads of romaine with the Universal Product Code of 0-27918-20314-9. The Produce Traceability Initiative codes on the cartons are 571280289SRS1 and 571280290SRS1.

“At Tanimura & Antle, food safety is a number-one priority and the company prides itself on its preventative measures,” according to the company’s notice posted on the Food and Drug Administration’s website. “It is unlikely that this product remains at retail establishments due to the shelf life of lettuce and the number of days that have passed.”

The sample was collected at a Walmart in Comstock Park, according to the Michigan agriculture department. According to the Tanimura & Antle notice, its recall “is based on the test result of a random sample collected and analyzed by the Michigan Department of Agriculture and Rural Development as part of their routine sampling program.”

The Tanimura & Antle recall, however, does not list Michigan as a destination for the recalled romaine. The single heads of romaine were packed on Oct. 15-16 and were shipped to Alaska, Oregon, California, Texas, Arkansas, Oklahoma, Indiana, Nebraska, Missouri, Tennessee, Wisconsin, New Mexico, South Carolina, Washington, North Carolina, Ohio, Virginia, Massachusetts, Illinois, and Puerto Rico.

The recall and Michigan advisory comes as the FDA is investigating two E. coli outbreaks involving separate strains of the pathogen that “are recurring, emerging or persistent strains,” according to an Oct. 28 news release.

Those two strains are “genetically related” to E. coli outbreaks related to romaine lettuce: one from a 2019 outbreak that led to 23 illnesses, and another from a 2018 outbreak that led to 21 illnesses and one death. Each of the current outbreaks have two cases reported in Michigan, according to the Centers for Disease Control and Prevention.

In the Oct. 28 announcement, the FDA said there was no evidence to link the outbreaks to any specific foods, and that a pathogen strain being linked to a food safety event in the past does not prove a link to a current outbreak.

Related story:

FDA says E. coli outbreaks have strains 

Lead photo: ( Courtesy FDA )

View fullsize

New Restrictions On Lettuce

View fullsize

Marc Fawcett-Atkinson, Local Journalism Initiative Reporter

October 22, 2020

Unprecedented federal import restrictions on romaine lettuce and salad mixes from California’s Salinas Valley point to problems in the U.S. agricultural system that supplies British Columbians with more than half their fresh vegetables, Canadian food safety researchers say.

Companies that import lettuce must now prove each shipment has been tested for E. coli, or was grown outside of California's Santa Clara, Santa Cruz, San Benito and Monterey counties. The directive will remain in force until Dec. 31, to cover the harvest season for California lettuce producers.

Lawrence Goodridge, director of the Canadian Research Institute for Food Safety at the University of Guelph, says repeated outbreaks of E. coli contamination from American farms precipitated the move.  There have been at least four outbreaks associated with romaine lettuce alone since 2016, Goodridge said. Investigations by American and Canadian authorities have also pinpointed the region as the source of several past E. coli outbreaks.

“The problem is nobody quite knows how the lettuce is becoming contaminated,” said Goodridge. “It could be the irrigation water, wild animals could run through the field and defecate. It’s hard to trace.”

Canada imported 183,300 tonnes of lettuce from the United States last year, and 64 per cent of that was from California. The remainder came from Arizona, Ohio and Florida. Between June 2019 and July 2020, more than 50,000 shipments of the vegetable crossed the border.

Lettuce is not the only vegetable that’s mostly imported to Canada outside the summer months. In 2018, about $2 million worth of vegetables flowed north, everything from kohlrabi to kale. Like lettuce, the majority was grown in California or other southwestern states.

Cattle are pastured on the hillsides surrounding the Salinas valley. That means manure can be washed downhill, gather in the bottom of the valley and possibly contaminate surface water and groundwater. This water is used to irrigate the hectares of lettuce and other vegetables growing in the valley bottom.

“The current temporary import requirements, implemented on Oct. 7, (are) a preventative measure due to the repetitive outbreaks linked to California romaine lettuce over the past four years,” the Canadian Food Inspection Agency said in an emailed statement.

The decision has received a tepid reception from American lettuce producers.

“Our producers will do their best to comply (with the new testing requirement) in an effort to continue shipping romaine lettuce to our valued trade partners in Canada,” the California Leafy Greens Marketing Agreement (LGMA), an association of shippers and handlers who adhere to shared food safety measures and are responsible for about 90 per cent of the leafy greens grown in the U.S., said in a written statement.

“However, this may not be feasible due to limited laboratory capacity. More importantly, product testing has not proven to be a reliable indicator of product safety.”

The organization is advocating for in-field testing instead of the post-harvest tests the Canadian government requires. It also said that recently implemented measures are sufficient to protect consumers.

The changes implemented by the LGMA classify irrigation water into categories depending on where it comes from, and how it will be used. Water used for overhead irrigation exceeds the U.S. Environmental Protection Agency’s “recreational standard” - clean enough for swimming. Water used for ground level or buried irrigation systems can fall below that standard. 

However, that’s not enough, said Keith Warriner, a food security professor at the University of Guelph. He would like to see the water tested more frequently, similar to the weekly or daily water testing requirements many states require for water to meet their recreational standard - an unfair comparison said the LGMA. 

“Comparing recreational water use and irrigation water use is questionable because swimmers taking a drink of the water they are swimming in is a very different risk profile than irrigating a crop that will then be exposed to the environment...before a consumer eats that product,” the organization said in an emailed statement. 

Nor does post-harvest cleaning do much, Goodridge and Warriner agreed.

“We know that washing actually spreads bacteria,” Goodridge said. “You’ve got to think that these are big processing operations (that) could be receiving lettuce from many different fields all over the place. If you have one batch that’s contaminated, but you’re running other batches through (the same cleaning line) at the same time, they can all get contaminated.”

Tracing a leaf of contaminated lettuce from a Canadian consumer’s plate back to individual farms is impossible, he said, especially since it could be more than two weeks before someone gets sick from the lettuce.

Nor is the federal government’s approach perfect.

Lettuce from other parts of the U.S. could also be contaminated, especially if water standards for processing and irrigation aren’t any higher.

And testing isn't very accurate because it only captures a minute snapshot of the total lettuce shipment, Goodridge said. A better approach would be to push the industry to implement system-wide changes that would address the problems at their source, such as treating all irrigation water with chlorine, to help deal with the issue.

These are largely regulatory matters Canada can’t control, since water and growing standards fall under U.S. jurisdiction. Still, the economic pressure exerted by an import ban could help push the industry to implement changes of its own volition.

“You have to have regulation,” said Goodridge. “But, ultimately, it’s when the industry takes food safety seriously, as opposed to seeing it as a necessary evil, (that) we will really begin to address these ongoing outbreaks.”

Canada Requires Romaine From Parts of California To Be Tested For E. Coli

Thanks in part to imported products, Canadians can enjoy fresh produce year-round. From 2016 to 2019, romaine lettuce from California was linked to outbreaks of E. coli illnesses in the USA and Canada. Food safety investigations by Canadian and US authorities identified the Salinas Valley growing region as a recurring source of the outbreaks.

To mitigate risk in the event of another outbreak this fall, the Canadian Food Inspection Agency (CFIA) is implementing temporary import measures aimed at preventing contaminated food from entering the marketplace.

Effective October 7, 2020, the CFIA will require importers to either provide proof that romaine lettuce destined for import into Canada does not originate from counties in the Salinas Valley, or provide an official certificate of analysis from an accredited laboratory confirming that the lettuce has below-detectable levels of E. coli.

CFIA is working closely and collaboratively with the US Food and Drug Administration to identify and respond to any potential outbreaks and continues to put in place effective preventive controls.

The testing applies to romaine lettuce as well as mixed salads containing romaine and will be required until December 31, 2020.

The program adds an extra layer of controls to the food safety measures in place under the Safe Food for Canadians Regulations (SFCR).

On January 15, 2020, SFCR requirements came into force for most businesses in the fresh fruits or vegetables (FFV) sector that import, export or engage in interprovincial trade.

Under the SFCR, FFV businesses are required to obtain a Safe Food for Canadians licence and maintain:

• preventive controls that address food safety hazards;

• preventive control plans that document risks to food and how they are addressed; and

• traceability documentation that tracks the movement of food one step forward and one step back in the supply chain.

Additional safeguards

Canada maintains specific import requirements to minimize potential hazards associated with romaine. For example, the importation of leafy greens from California is limited to products supplied by certified members of the California Leafy Greens Marketing Agreement (LGMA). LGMA certified members must adhere to food safety requirements subject to regular audits by the California Department of Food and Agriculture.

In addition, the CFIA has a regular monitoring program for E. coli O157:H7 in fresh vegetables and is also testing 1,000 more samples of lettuce and products containing lettuce per year.

For more information, read the CFIA's guidance Import requirements for romaine lettuce from the United States.

Source: Canadian Food Inspection Agency (CFIA)

Quick Facts

• The CFIA plays a critical role in safeguarding a healthy food supply system, ensuring the foods Canadians eat are safe and facilitating the trade of food and food products internationally.

• More than 50,000 shipments of romaine lettuce or salad mixes containing romaine lettuce were imported into Canada from June 2019 to July 2020.

• Romaine is associated with elevated food safety risks. In Canada, there have been seven documented outbreaks of illnesses associated with romaine lettuce, and 16 recalls of romaine lettuce or products containing romaine lettuce due to E. coli O157:H7 from 2010 to 2019.

• Under this new requirement, romaine from Salinas must be tested in a laboratory accredited by the Standards Council of Canada (SCC), the Canadian Association for Laboratory Accreditation (CALA) or another accreditation body that is a signatory to the International Laboratory Accreditation Cooperation (ILAC) Mutual Recognition Agreement (MRA).

Related Products or Associated Links

• Import requirements for leafy green vegetables from California and Arizona

• Public Health Notice – United States outbreak of E. coli infections linked to romaine lettuce with implications for Canadians

View fullsize

Canada To The U.S.: Keep Your Romaine Lettuce

by Jessica Fu

10.08.2020

“Canada’s making a clear statement there”: As the U.S. continues to deal with leafy green E. coli outbreaks, our northern neighbors are taking a stand.

Beginning this week, leafy greens growers in America’s Salad Bowl will have a much harder time shipping to Canada—after food safety officials up north imposed new, strict restrictions on romaine lettuce imports in an effort to stave off potential E. coli outbreaks this fall.

Last week, the Canadian Food Inspection Agency announced that it would effectively ban imports of romaine sourced from major growing regions in the Salinas Valley unless growers could certify through lab testing that their shipments had “below-detectable levels of E. coli.” The rules took effect on Wednesday and are scheduled to run through the end of the year. Officials said the move was prompted by the numerous E. coli outbreaks linked to U.S.-grown romaine over the past few years. 

“From 2016 to 2019, romaine lettuce from California was linked to outbreaks of E. coli illnesses in the USA and Canada,” the announcement read. “To mitigate risk in the event of another outbreak this fall, the Canadian Food Inspection Agency is implementing temporary import measures aimed at preventing contaminated food from entering the marketplace.”

Some food safety experts weren’t surprised by the move, given just how frequently E. coli outbreaks have been traced back to romaine.

“From 2016 to 2019, romaine lettuce from California was linked to outbreaks of E. coli illnesses in the USA and Canada.”

“Canada gets most of its lettuce from [the U.S.],” said Bill Marler, a prominent food safety lawyer and publisher of Food Safety News. “So when we have outbreaks in the U.S., Canada usually has one, too.”

There were last fall’s E. coli outbreaks linked to romaine lettuce sourced from the Salinas Valley. Then there was the 2018 one. Then there was the 2017 one, which also included growers in Arizona and Mexico. Of course, E. coli is far from the only dangerous pathogen that regularly rips through our food system, and E. coli outbreaks have also been traced back to other food items, from other regions, at other times of the year. However, Marler suspected that Canada’s move specifically targeting romaine harvested from Salinas in the fall was the result of getting “whacked” by these particular imports one too many times.

The new requirements may also suggest that Canada is raising doubts about the ability of American leafy greens growers to prevent foodborne illness outbreaks, said Angela Anandappa, executive director of food safety non-profit Alliance for Advanced Sanitation.

“This is a little radical for Canada to do,” she said. Anandappa interprets the restrictions as saying: “We have lost trust in your ability to produce this kind of product.”

“Canada’s making a clear statement there,” she added.

The move’s short notice took growers by surprise, said Trevor Suslow, extension research specialist at the University of California, Davis, who works with farms on food safety issues. In fact, he doubted that many farms would be able to meet the high testing requirements outlined in the new rule—which requires that they take and test 60 samples from every truckload of romaine lettuce products, including mixed salad bags.

The move could indirectly encourage producers to take greater precautions along the growing process.

In response to the move, California Leafy Greens Marketing Agreement—a voluntary program composed of major growers who commit to food safety standards and audits—indicated that it might lead to bottlenecks in leafy green supply chains. After all, this is one of America’s top produce exports to Canada, which imported $333 million worth of lettuce in 2018, according to the Department of Agriculture.

“The measures required in these new restrictions for post-harvest testing are not achievable on an industry-wide basis in the timeframe provided,” the marketing group wrote in a statement. It also suggested that industry groups and government officials were working behind the scenes “to resolve this situation to the benefit of all parties.” (California Leafy Greens Marketing Agreement declined a request for more information.)

The one point everyone I spoke with agreed on was that testing alone doesn’t safer lettuce make. While it can help trace outbreak sources, and minimize the number of people who get sick from recalled products, it doesn’t directly address the root causes of contamination. For example, leafy greens farms are often located near livestock production, which can contaminate water used to irrigate lettuce. Down the line, contaminated water might also be used to wash and process lettuce before shipment. Then, at the consumer level—while cooking lettuce with heat may kill any potential pathogens—lettuce is typically eaten raw.

Having said that, Marler believes the move could indirectly encourage producers to take greater precautions along the growing process.

“If [producers] want to continue to sell products from Salinas to Canada, they’re going to have to play by the rules,” he said. “And I think that might well be a net benefit to food safety in the U.S.”

Lead photo: iStock /Juanmonino Eating Sourcing

Also tagged canada, lettuce, romaine

Jessica Fu is a staff writer for The Counter.

View fullsize

Lettuce Linked To 40 E. Coli Outbreaks In A Decade – Most Related To Romaine

Romaine Lettuce's Growing Popularity,

However, Doesn't Explain Its Link To Numerous Outbreaks.

Sept. 16, 2020, / Source: NBC News

By Sara G. Miller

Leafy greens are a common culprit of foodborne illnesses, with the produce linked to 40 outbreaks of a serious strain of E. coli from 2009 to 2018, a report published Wednesday in the journal Emerging Infectious Diseases finds.

Among those outbreaks, one lettuce, in particular, bore the brunt of the blame: romaine. (Recall 2018, a year rocked by two massive romaine-linked E. coli outbreaks?)

Of outbreaks linked to a specific leafy green — rather than a mix — 54% were linked to romaine. Spinach and iceberg lettuce were each linked to 17% of the outbreaks, and cabbage, green leaf and kale were each linked to 4%.

View fullsize

To View the Above Video, Please Click Here

It's not entirely clear why romaine was the most common culprit in the outbreaks. The researchers noted, for example, that more iceberg lettuce was harvested and sold each year from 2009 to 2017 than romaine.

Romaine did grow in popularity during the decade analyzed, the researchers wrote: By the end of the study period, more money was spent on romaine lettuce than on iceberg. But this alone doesn't explain why romaine was responsible for so many outbreaks.

Another possible explanation, the researchers posited, is the lettuce's shape, which could provide an entry point for pathogens: "Romaine is tall with loosely clumped leaves, open at the top; iceberg is smaller with compact leaves."

Other outbreaks were linked to mixed greens, including three romaine and iceberg mixes, a butter lettuce and radicchio mix, and a spinach and spring mix.

The report focused on outbreaks of a type of E. coli called Shiga toxin-producing E. coli, or STEC. The name refers to a toxin produced by the bacteria that makes people sick. Symptoms can include diarrhea and vomiting, according to the Centers for Disease Control and Prevention. Most people recover on their own within 5 to 7 days, though some may need medical care.

Related NEWS

Food-poisoning outbreak that is in 6 states is likely from ground beef

The decade of outbreaks, which occurred in the United States, Canada or both countries, accounted for 1,212 illnesses, 420 hospitalizations and eight deaths, according to the report. A total of 77 cases of hemolytic uremic syndrome, a kidney problem that requires hospitalization, were also attributed to the outbreaks.

Shiga toxin-producing E. coli are linked to about 265,000 illnesses each year in the U.S., according to the report. One type of STEC in particular, STEC O157, tends to cause more severe illness. The most common source of this infection is ground beef, followed by leafy greens. Indeed, STEC O157 was responsible for 32 of the outbreaks described in the report.

Though leafy greens are grown year-round in the U.S., more outbreaks began in October and April than any other month of the year. It's unclear why this seasonality in outbreaks occurred, the study authors wrote.

There are several reasons why leafy greens are particularly susceptible to E. coli contamination, starting with how the crops are cultivated, Benjamin Chapman, a professor and food safety specialist at North Carolina State University, said.

"The vast majority of lettuce production is outside and requires a lot of water," Chapman, who wasn't involved with the report, said in an email. And in the U.S., it's mostly grown in areas where animals — a source of E. coli — are also raised. E. coli contamination can come from sources such as irrigation water, animals, and handling.

"We know from earlier outbreaks that a little bit of contamination in the field can lead to cross-contamination," he said.

Once that contamination has made it onto the plant, it's "very difficult to remove," Chapman said. Produce is triple-washed in processing plants, and in the home, a person may be able to rinse off "90 to 99% of what's there, but that may not be enough depending on how much" contamination there is, he added.

And because lettuce is almost always eaten raw or undercooked, "any contamination that makes it to the plate ends up in the gut," he said.

Avoiding outbreaks entirely is, unfortunately, a supply chain issue, he said.

This story was originally published on NBC News.

View fullsize

Salmonella Has Found A Way To Evade Plant Defenses

By Chrissy Sexton

Earth.com staff writer

Researchers at the University of Delaware have discovered that wild strains of salmonella can evade a plant’s immune defenses by invading the leaves through the stomata. The invaded plant does not show any obvious signs of infection, and the pathogens cannot be simply rinsed off, which means they can easily jump to people.

Stomata are tiny pores that open when there is plenty of sunlight for photosynthesis and close at night. The pores also close upon detection of threats such as drought or microbial pathogens.

Study co-author Professor Harsh Bais explained that some pathogens like fungi can barge into a closed stoma using brute force. Since bacteria lack the enzymes needed to use this type of force, they search for openings in the roots and stomata.

According to Professor Bais, however, bacterial pathogens like salmonella have now found a way to reopen closed stomata and gain entry to the plant.

“What’s new is how the non-host bacteria are evolving to bypass plant immune response. They are real opportunists. They are absolutely jumping kingdoms. When we see these unusual interactions, that’s where it starts to get complex,” said Professor Bais.

The risk of pathogen contamination increases when plants are bred to produce higher yields, or when low-lying crops are grown too close to a livestock field. The researchers have been investigating these issues for about five years.

Companies take various precautions to kill surface bacteria, but they can’t see or treat human pathogens that already have gotten into the leaf.

“The food industry works tirelessly to make the product as safe as they can,” said study co-author Professor Kali Kniel. “But even then, we are growing these products outside, so they’re accessible to wildlife, wind, dust, and water that may transmit microorganisms. It’s a tough situation.”

Graduate student Nicholas Johnson conducted extensive lab experiments to examine how stomata on spinach and lettuce respond to salmonella, Listeria, and E. coli – three human pathogens that leave no trace of infection. He tracked the size of the stomata openings every three hours after the bacteria were introduced.

“He had to sit under a microscope and count the aperture sizes,” said Professor Bais. “And he has to be meticulous.” The tedious work revealed that the salmonella strain was reopening the stomata. “Now we have a human pathogen trying to do what plant pathogens do. That is scary,” noted Bais.

The researchers said it would be particularly scary if salmonella invaded plants on a vertical farm, where plants are grown in vertical rows hydroponically. “If this hits vertical farms, they don’t lose a batch, they lose the whole house,” said Bais.

“This project has mutant Salmonella strains and that allows us another angle on the molecular biology side,” said Professor Kniel. “The individual mutations are important for the salmonella structure and the regulation of stress.”

“When we used mutant strains we saw big differences in the ability to colonize and internalize – and that’s what consumers hear a lot about. You are not able to wash it off.”

“We can also look at which genes or part of the organism might be more responsible for the persistence on the plant – making it last longer and stronger. That is so important when you think of food safety issues.”

The study is published in the journal Frontiers in Microbiology.

By Chrissy Sexton, Earth.com Staff Writer

Food Safety And E. coli in Aquaponic And Hydroponic Systems

This document is The Aquaponics Association’s response to a recent publication on E. coli in Aquaponic and Hydroponic systems.

PDF Version: Food Safety and E. Coli in Aquaponic and Hydroponic Systems

April 27, 2020

By Tawnya Sawyer; Nick Savidov, Ph.D.; George Pate; and Marc Laberge 

Overview of the Study

On April 6, 2020, Purdue Agriculture News published a story about a study related to the contamination risk of Shiga toxin-producing E. coli (STEC) in Aquaponic and Hydroponic production. The full study was published in MDPI Journal Horticulturae in January 2020.

Researchers conducted the study from December 2017 through February 2018. The Study consisted of side-by-side aquaponic and hydroponic systems in a controlled environment lab growing lettuce, basil, and tomatoes with tilapia. The purpose of the study was to identify the food safety risks associated with soilless systems. The study indicates that both the aquaponic and hydroponic systems contained Shiga toxin-producing E. coli (STEC) at the time of sampling. It did not find the presence of Listeria spp., or Salmonella spp. 

The authors contend that the aquaponic system and specifically the fish feces were likely the sources of E. coli. However, we believe that there is no evidence to prove that this was the actual source of contamination since the authors admit traceback was not performed, and there were several other possible introductions.

The pathogen was present in the water and on the root system of the plants. The researchers did not detect it in the edible portion of the plants. However, if the water is positive for a contaminant, and it accidentally splashes onto the edible portion of the crop throughout its life, or during harvest, this could still result in a food safety concern.

History of E. coli in Soil-less growing systems 

Until now, researchers have only discovered environmental E. coli in soilless growing systems. It is essential to note that there are hundreds of types of non-fecal coliform bacteria in the air, water, soil, as well as the fecal coliform bacteria represented mostly by E.coli in the waste of all mammals, humans, and some birds. A vast majority of these coliforms are perfectly harmless.

The E. coli found in this Study — Shiga toxin-producing O157:H7 — historically has been associated with warm-blooded mammals, more specifically bovine fed corn in feedlots (Lim JY et al. 2007), as well as swine and turkeys. Further research must be performed to prove that cold-blooded, non-mammal aquatic species such as tilapia can harbor this strain of pathogenic E. coli. A wide group of studies, university professors, and industry professionals currently refute the possibility that tilapia can harbor this strain. The lack of evidence detailing the ability of aquatic animals to harbor E. coli makes the fish contaminated with this specific strain of bacteria very rare and suspect.

Many foodborne illnesses from fresh produce such as romaine lettuces, green onions, herbs, and sprouts, are traced back to the soil; the irrigation water used in these crops (Solomon et al. 2002); the seed stock; or poor sanitation in handling facilities.

There are a wide variety of community and commercial aquaponic and hydroponic growing facilities that routinely perform pathogen testing and have not identified this pathogen present. If it was present, traceback procedures would be followed to identify and remove the source, as well as any necessary food safety precautions and recalls performed.

Our Position

The Aquaponic Association and its members agree that food safety and proper handling practices are critical to commercializing our industry and the safety of our customers. One thing that the study points out is that a contaminant can occur in a soilless system, which creates a potential food safety concern. We agree on this; however, we have numerous concerns with the procedures and statements made in the publication.

We have reached out to the professional investigator on this study Hye-Ji Kim to get answers to essential questions that the study publication does not adequately address. There are significant gaps and questions with the study.

 Concerns About the Study Findings and Publication 

Lack of Traceability

The study group is unsure how the pathogen was introduced into the two systems. They admit that no traceback was performed to identify the source of contamination. They speculate both in the study and in their email response that this pathogen was:

1) Accidentally introduced

2) That it is from the fish feces in the aquaponics system that splashed into the hydroponic system through the open top of the fish tank during feeding,

3) that it was from contaminated fish stock (which were provided by the Purdue Animal Sciences Research and Education Center)

4) That it was human contamination from visitors or operator handling issues.

A traceback was not conducted as it was not within the scope of the study (Kim personal communications). We disagree; the discovery of O157:H7 strain in the university greenhouse with the suspicion of fish being contaminated should have resulted in immediate action in order to track down the source of contamination and prevent infection of the university students and staff. Outside of a University setting, traceback would have been mandatory in a commercial facility. It is questionable that the University did not perform these procedures because it was “out of the scope of the study”.

Questioning Fish Feces as the Source of Contamination

Blaming fish feces as the contaminating source seems incredibly misleading when so many other options exist, and no traceback proved that as the source. The contents of the fish intestines were tested for the presence of E. coli, and none was found (Kim personal communications). It seems that if the fish does not have STEC E. coli inside its gut, then it is more likely the fish feces being positive would be related to the contaminated water that the feces was floating in.

In wild fish species, levels of E. coli appear to follow trends similar to ambient water and sediment concentrations; as concentrations in their environments rise, so do concentrations within the fish (Guillen et al., 2010).

Furthermore, it seems very suspect that a two-month-old system in a controlled environment lab could have been so quickly contaminated. It is well-known that E.coli cannot survive in a biologically-active environment, such as an anaerobic digester or aquaponic system (T.Gao et al., 2011). E. coli are outcompeted by other microorganisms, which adapted to survive in the environment outside animal guts much better than E. coli. Thus, E. coli O157:H7, which is specially adapted to live in cattle guts, will inevitably be replaced by other microorganisms.

As for the hydroponic system showing positive results, this also seems suspect if the nutrients were synthetic, as there would be very little chance for the E. coli to survive without a biological host or continuous contamination source being present. An accidental exposure in the hydroponic system would have become diluted over time, or the pathogen died off to the point that they would have been undetectable. The fact is the organic matter in hydroponics is virtually absent and, therefore, provides a poor environment for E. coli growth and propagation (Dankwa, 2019). Therefore. one would need a continuous source, not an accidental one (like splashing), in order to maintain the E. coli population in hydroponics.

Since both systems were contaminated, we suggest that there is a more likely common pathogen source that the researchers did not correctly identify and remove. The source of contamination could be from source water, filtering system, repurposed equipment, airborne in the greenhouse or HVAC system, human vector, lab equipment, the seed stock, nutrients, or other inputs.

The Purdue Animal Research and Education Center, where the researchers sourced the fish, is an operation that also has swine, cattle, and poultry production. Research suggests that pathogenic E. coli can travel 180 m through airborne exposure (Berry et al., 2015). Airborne exposure poses a more significant risk to controlled environments as pathogens can persist in the HVAC system (Riggio et al., 2019). STEC has the potential to live in dust particles for up to 42 weeks, which can act as a possible vector of contamination if there is a continuous source. Therefore, even a slight possibility of the pathogenic Shiga-producing O157:H7 strain of E. coli transfer from the Animal Research and Education Center resulting in the uncontrolled cross-contamination of other research labs and facilities certified below Biosafety level 2 not designed to work with the pathogenic bacteria would raise a serious concern about the existing safety practices (Boston University).

Lack of 3rd Party or Peer University Test Verification

It has also been recognized that there is a high frequency of false-positive signals in a real-time PCR-based “Plus/Minus” assay (Nowrouzian FL, et al., 2009). Hence the possibility that the PCR verification method may have resulted in inaccurate results. The pathogen was not verified by a 3rd party lab to be actual STEC E.coli O157:H7. Only positive or negative results were obtained for this study.

We recommend several other universities and third-party labs to run samples and validate the results. However, no samples have been provided, which may be impossible to obtain based on the study being conducted in early 2018. Without this verification, there are questions about the possibility of false-positives due to the presence of environmental E.coli, fecal coliforms, or a wide variety of other bacteria commonly found in nutrient-rich environments (Konstantinidis et al., 2011).

Impact of Sterilization

The study conclusion suggests that sterilization efforts are critical. “Our results indicated that contamination with bacterial pathogens could likely be reduced in aquaponic and hydroponic systems if the entire systems were thoroughly sanitized before each use and pathogen-free fish were used for the operation.” This statement is inaccurate and could be detrimental to proper food safety practices. As the microflora of the system develops, it creates an environment that can suppress phytopathogens (Bartelme et al., 2018) and other zoonotic pathogens as a result of antibiotic compounds released by beneficial bacteria (Compant et al., 2005). In Recirculating Aquaculture Systems (RAS), some microbial communities take over 15 years to develop (Bartelme et al., 2017), resulting in greater stability over time.

Many papers support this hypothesis with regards to probiotics in wastewater treatment, aquaculture, and hydroponics. Microbial community analysis also depicts a greater microbial diversity in aquaponics over decoupled or aquaculture systems (Eck et al., 2019), indicating a more significant potential for suppression of pathogens in coupled aquaponic systems over RAS or decoupled aquaponic system. No pathogens were discovered in a mature coupled aquaponics system during 18 years of continuous research in Canada since 2002 (Savidov, personal communications).

These findings support the argument that more biologically mature systems are less likely to develop pathogens and that periodic sanitation should not be done outside of initial start-up unless a zoonotic pathogen (Henderson 2008), is detected. If a pathogen is found, producers should follow proper sanitation and recall procedures.

Conclusion

Overall, this and other research into food safety are ongoing, and new information becomes available continuously to help shape the best practices for proper greenhouse management. As the Aquaponic Association, we hope to provide the most accurate and reliable resources for this purpose. At the same time, we hope to reduce the possibility of studies like this creating unnecessary fear, or unsubstantiated claims that could harm the growth of the aquaponic (and hydroponic) industry. When a document like this is published, it will be quoted by the media, and referenced in other studies as if it is an absolute. Other research must be performed to validate or negate this study’s outcomes.

Our findings conclude that while there is a low chance of the persistence of a pathogen in properly designed aquaponic and hydroponic systems, there is still a potential concern. No agricultural system is immune to this. Compared to soil production, soil-less crops grown in a controlled environment are far less likely to become infected pathogens from mammals, birds, and other creatures which are difficult to prevent in field crop production. Human contamination or poor handling practices are of significant concern (Pattillo et al., 2015). The best way to avoid risk is to adhere to food safety guidelines set forth by the USDA, GlobalGAPs, the Aquaponic Association, and other accredited organizations.

contact: info@aquaponicsassociation.org

References

Bartelme, R.P., McLellan, S.L., Newton, R.J., 2017. Freshwater Recirculating Aquaculture System Operations Drive Biofilter Bacterial Community Shifts around a Stable Nitrifying Consortium of Ammonia-Oxidizing Archaea and Comammox Nitrospira. Front. Microbiol. 8. https://doi.org/10.3389/fmicb.2017.00101

Bartelme, R.P., Oyserman, B.O., Blom, J.E., Sepulveda-Villet, O.J., Newton, R.J., 2018. Stripping Away the Soil: Plant Growth Promoting Microbiology Opportunities in Aquaponics. Front. Microbiol. 9, 8. https://doi.org/10.3389/fmicb.2018.00008

Berry, E.D., Wells, J.E., Bono, J.L., Woodbury, B.L., Kalchayanand, N., Norman, K.N., Suslow, T.V., López-Velasco, G., Millner, P.D., 2015. Effect of Proximity to a Cattle Feedlot on Escherichia coli O157:H7 Contamination of Leafy Greens and Evaluation of the Potential for Airborne Transmission. Appl. Environ. Microbiol. 81, 1101–1110. https://doi.org/10.1128/AEM.02998-14

Compant, S., Duffy, B., Nowak, J., Clément, C., Barka, E.A., 2005. Use of Plant Growth-Promoting Bacteria for Biocontrol of Plant Diseases: Principles, Mechanisms of Action, and Future Prospects. Appl. Environ. Microbiol. 71, 4951–4959. https://doi.org/10.1128/AEM.71.9.4951-4959.2005

Dankwa, A.S., 2019. Safety  Assessment of Hydroponic Closed System 127. https://digitalcommons.library.umaine.edu/cgi/viewcontent.cgi?article=4052&context=etd

Eck, M., Sare, A., Massart, S., Schmautz, Z., Junge, R., Smits, T., Jijakli, M., 2019. Exploring Bacterial Communities in Aquaponic Systems. Water 11, 260. https://doi.org/10.3390/w11020260

Guillen, Wrast, Environmental Institute of Houston, 2010, Fishes as Sources of E. coli Bacteria in Warm Water Streams, https://www.uhcl.edu/environmental-institute/research/publications/documents/10-015guillenetalfishreport.pdf

Henderson, H., 2008. Direct and indirect zoonotic transmission of Shiga toxin-producing Escherichia coli. J. Am. Vet. Med. Assoc. 232, 848–859. https://doi.org/10.2460/javma.232.6.848

Konstantinidis, Chengwei Luo, 2011. Georgia Tech Institute, Environmental E. coli: New way to classify E. coli bacteria and test for fecal contamination, https://www.sciencedaily.com/releases/2011/04/110411152527.htm

Lim JY et al., Escherichia coli O157:H7 colonization at the rectoanal junction of long-duration culture-positive cattle. Appl Environ Microbiol. 2007;73:1380–1382 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1828644/

Boston University Agent Sheet E.coli EHEC or STEC) (https://www.bu.edu/researchsupport/safety/rohp/agent-information-sheets/e-coli-0157h7-agent-information-sheet/).

Nowrouzian FL1, Adlerberth I, Wold AE., 2009 High frequency of false-positive signals in a real-time PCR-based “Plus/Minus” assay. https://www.ncbi.nlm.nih.gov/pubmed/19161539

Riggio, G., Jones, S., Gibson, K., 2019. Risk of Human Pathogen Internalization in Leafy Vegetables During Lab-Scale Hydroponic Cultivation. Horticulturae 5, 25. https://doi.org/10.3390/horticulturae5010025

Solomon et al., Effect of Irrigation Method on Transmission to and Persistence

of Escherichia coli O157:H7 on Lettuce Journal of Food Protection, Vol. 65, No. 4, 2002, Pages 673–676 https://www.ncbi.nlm.nih.gov/pubmed/11952218

1. Gao*, T. Haine,  A. Chen,  Y. Tong, and X. Li, 2011, 7 logs of toxic strain of E. coli  were removed by mesophilic AD process while ~ 5 logs increase of the strain were seen in water control with the same condition for 7 days

Pattillo*, Shaw, Currey, Xie, Rosentrater, 2015, Aquaponics Food Safety and Human Health, https://southcenters.osu.edu/sites/southc/files/site-library/site-documents/abc/aquaponics_workshop/AquaponicsFoodSafetyandHumanHealthAllenPatillo.pdf

Risk of E. coli In Hydroponic And Aquaponic Systems May Be Greater Than Once Thought

View fullsize

Hye-Ji Kim (left), pictured with graduate student Seunghyun Choi, found the presence of E. coli bacteria in aquaponic and hydroponic growing systems, suggesting the bacteria could reach produce consumers. (Agricultural Communication photo/Tom Campbell)

WEST LAFAYETTE, Ind. – A spate of foodborne illnesses in leafy greens and other produce in recent years has sickened consumers and disrupted growers and supply chains. It’s been thought that hydroponic and aquaponic systems could reduce these issues since there is little opportunity for pathogens like E. coli to contaminate the edible parts of plants.

A Purdue University study, however, has found the presence of Shiga toxin-producing E. coli (STEC) – the same bacteria that have made consumers of several produce products ill – in hydroponic and aquaponic growing systems. Hye-Ji Kim, an assistant professor of horticulture and the study’s corresponding author, said the findings suggest growers using these systems should be careful in handling and harvesting to avoid contamination.

“Many people think that there is no chance that E. coli could be present in these systems and that risk of contamination is low,” said Kim, whose results were published in the journal Horticulturae. “Our findings suggest there is some potential for food safety concerns. We’re not saying that these foods are unsafe, but that it’s important to handle these plants properly and carefully.”

View fullsize

Aquaponic and hydroponic growing systems are thought to have little risk of containing bacteria that can sicken produce consumers. After finding E. coli in both types of systems, Hye-Ji Kim suggests growers to use caution to not introduce the bacteria to their operations. (Agricultural Communication photo/Tom Campbell)

The E. coli outbreaks that have occurred in recent years tend to happen in leafy greens and other vegetables grown in irrigated fields. Potential sources could be from E. coli in manure or groundwater that reaches the edible portions of plants, or from those contaminants getting to plants after root damage by wild animals.

Proponents of hydroponic and aquaponic systems suggest their growing methods would reduce or eliminate any risk of contamination. Both soilless systems, hydroponic plants are grown in water and chemical fertilizers or nutrient solutions, and aquaponic systems include the raising of fish, with fish wastewater utilized as water and nutrient source for the plants.

View fullsize

The fish used in aquaponic growing systems may introduce E. coli to water and potentially produce crops, and accidental contamination is possible in hydroponic systems. Hye-Ji Kim and Yi-Ju Wang (pictured) suggest growers take careful steps to ensure that these bacteria don’t reach plants that could sicken consumers. (Agricultural Communication photo/Tom Campbell)

Kim, Yi-Ju Wang, a graduate student in Kim’s lab, and Amanda Deering, a Purdue clinical assistant professor of food science, set up both hydroponic and aquaponic systems for growing lettuce, tomatoes, and basil for about two months. The scientists found E. coli in both systems at the time of harvest.

In the aquaponic system, the authors believe the E. coli was introduced by the fish. The bacteria was found in the water, on plant roots, and in fish feces.

“Our separate aquaculture system confirmed that fish feces were a major source of contamination with STEC in the aquaponic system,” the authors wrote. “These results indicate that introducing contaminated fish can be a source of foodborne pathogens in aquaponics.”

The presence of E. coli in the hydroponic system, in which fish were not used, suggests that the bacteria was introduced accidentally. Kim believes it could have splashed from a nearby aquaponic system or have been introduced by a visitor who brought it in from outside the greenhouse. Either way, the presence in the system suggests that accidental contamination is a real risk.

E. coli was also found on plant roots in both systems, but the bacteria did not internalize in the plants. In other words, even with the bacteria present in water and on the roots, the edible portions of the plants were still safe to consume.

The key, Kim says, is proper handling to ensure that E. coli or other pathogens don’t make it to the edible parts of plants. Damaged roots would allow bacteria into the plants, potentially making it to edible portions internally. And the splashing of water during growing or harvesting could introduce bacteria to the edible portions of the plants.

“The best way to manage these issues is to not touch roots or water throughout production cycles. If you do, you should thoroughly wash your hands before touching the edible parts of the plants,” Kim said. “Proper sanitization of equipment is also important. And acquiring fish that do not contain E. coli would also be beneficial.”

Kim’s lab is continuing to investigate food safety risks in hydroponic and aquaponic systems. Projects include damaging roots and simulating splashes to understand how much contamination can occur.

The Indiana State Department of Agriculture, the U.S. Department of Agriculture’s National Institute of Food and Agriculture, and the Purdue University College of Agriculture funded this research.

Writer: Brian Wallheimer, 765-532-0233, bwallhei@purdue.edu

Source: Hye-Ji Kim, 765-496-0122, hjikim@purdue.edu 

Note to Journalists: A portrait of one scientist, a picture of another scientist in the lab and a picture of a growing system are available for journalists to use via Google Drive.

ABSTRACT

The Occurrence of Shiga Toxin-Producing E. coli in Aquaponic and Hydroponic Systems

Yi-Ju Wang1, Amanda J. Deering2, and Hye-Ji Kim1

1. Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, IN

2. Department of Food Science, Purdue University, West Lafayette, IN

Food safety concerns have been raised over vegetables and herbs grown in aquaponics and hydroponics due to the reuse of wastewater and spent nutrient solutions. This study was conducted to determine the occurrence of foodborne pathogens in greenhouse-based aquaponic and hydroponic systems. Fish feces, recirculating water, roots, and the edible portions of lettuce, basil, and tomato were collected at harvest, and microbiological analyses were conducted for the bacterial pathogens Shiga toxin-producing Escherichia coli (STEC), Listeria monocytogenes, and Salmonella spp. Enrichments and selective media were used for the isolation, and presumptive positive colonies were confirmed by PCR. STEC was found in fish feces, in the water of both systems, and on the surface of the roots of lettuce, basil, and tomato regardless of the system. However, contaminated water did not lead to the internalization of STEC into the roots, leaves, and/or fruit of the plants. Meanwhile, L. monocytogenes and Salmonella spp. were not present in any samples examined. Our results demonstrated that there are potential food safety hazards for fresh produce grown in aquaponic and hydroponic production systems.

Agricultural Communications: 765-494-8415;

Maureen Manier, Department Head, mmanier@purdue.edu  

Safe, Not Sorry

View fullsize

By Leslie F. Halleck

Food poisoning is not something you wish on anyone.

It’s horrible, miserable and downright deadly.

If you’ve ever had an E. coli or Salmonella infection, then you probably take food safety seriously. I know I do. Outbreaks of E. coli have plagued the field-grown leafy greens industry for the past three years in a row, with the most recent outbreaks sending romaine lettuce to the garbage bins across the country. With each recall, consumers are forced to focus more closely on where and how their food is grown.

With animal feces and surface water contamination for field-grown produce at the center of most of the leafy greens recalls, some food companies and restaurants are making shifts to buy from hydroponic and CEA producers. While this is a great opportunity for those of you growing under glass or in controlled environments, don’t make the mistake of thinking that you won’t come under the same safety and transparency scrutiny, or liability.

There are certainly many reasons why agriculture is making a big move indoors. It can be argued that CEA offers more local and sustainable food production and that it requires less water than field growing and doesn’t impact topsoil or lead to erosion. Controlled growing may also create conditions where fewer, or no, pesticides or herbicides are used. And when you’re growing local, with potentially less pest pressure, you can grow edible varieties that offer up better flavor and nutritional value, versus having to grow varieties or use harvesting methods that cater to shipability.

While there may be a perception that the boundaries created by greenhouses or controlled environments mean safer produce, we all know that there are still plenty of ways contamination can happen. Growing in a controlled environment means you lose the benefits of nature’s sanitizers: air and sunlight. Close monitoring of all environmental conditions is a must in hydroponics and controlled environments. Anywhere there is water involved, pathogens can spread. And of course, any time you have people involved in your production process, there’s ample opportunity for all sorts of contamination.

With venture capitalists jumping into the CEA game, and new operations launching left and right, we can also argue that this is a very young industry with a lot of learning and growing to do. Mistakes are bound to happen. Many CEA growers may not even have a good understanding of what translates to safe, or not safe, growing or processing procedures. Technology is changing rapidly, influencing a variety of production techniques utilized differently by different growers. You do have much better opportunities for authentic transparency and traceability as a CEA, but collective standard protocols aren’t yet where we need them to be.

This is a very young industry with a lot of learning and growing to do.

Enter, the CEA Food Safety Coalition (FSC). This new independent and member-governed organization debuted in 2018 and just recently announced the appointment of its first executive director. The goal of the organization is to bring together CEA growers of leafy greens to self-submit to external audits of their production processes. Then, thorough evaluation to develop appropriate food safety standards and consumer education.

If you grow leafy greens using any sort of controlled environment, be it hydroponics, aeroponics or aquaponics, and you’re willing to submit to a third-party food safety audit, then you are welcome to join the CEA FSC.

If you grow produce, do you have a Farm Food Safety Plan (FFSP) in place? If not, it’s time to get your house in order. You need to make sure you’re keeping a detailed record of your operation’s procedures and adherence to growing and processing safe greens or other produce. I suspect the CEA FSC will be working with members to develop FFSPs that help them fine-tune their safety measures and comply with federal regulations.

Good news if you’ll be attending the United Fresh 2020 Convention & Expo, because they’ve just partnered with the CEA FSC to create a new Controlled Environmental Pavilion at the show. The Pavilion will showcase thought leaders and foster discussions between experienced and new growers, as well as highlight new technologies and food safety issues. If you’re a CEA or service provider, you can now book booths both inside and adjacent to the Pavilion.

No one likes getting food poisoning, and we already throw away far too much food in this country. Growing as a CEA offers up the ability to not only limit waste of resources but also produce safer and contamination-free food. Consumers are willing to pay you a bit more for your produce when you can be totally transparent about your methods and food safety concerns. But it’s going to take a lot more research, learning, communication, and community standards before CEAs can truly take the lead on produce safety.

Lead photo: PHOTO: © freshidea | Adobe stock

Leslie (CPH) owns Halleck Horticultural, LLC, through which she provides horticultural consulting, business and marketing strategy, product development and branding, and content creation for green industry companies. lesliehalleck.com

Another E. coli Outbreak – A New Solution to Help

• CO2GRO

• December 6, 2019

Another continent-wide romaine lettuce recall from an outbreak of E. coli is underway with 67 people reported sick in 19 states. The source of the latest outbreak was found in irrigation reservoir sediments. The chief suspect is wild animal feces entering the irrigation reservoir. The last several outbreaks began on farms in Monterrey, Santa Barbara, Salinas, and Santa Maria, California growing romaine lettuce.

The economic impact including costs of shipping returns, taking the lettuce off shelves, plant destruction, medical care costs and increases in retail prices due to shrinking supply can be up to $350 million. The Center for Disease Control (CDC) estimates that 265,000 STEC infections occur each year in the United States. E. coli O157:H7 causes more than 36% of these infections.

View fullsize

E. coli are bacteria that typically live in the intestines of healthy humans and animals. Most types of E. coli bacteria are harmless but some can cause severe diarrhea and urinary tract infections while more severe strains can cause kidney failure in children and other severe symptoms. 

Leafy greens are highly regulated in California but vulnerable to bacterial infections. The primary method for preventing E. coli is good hygiene in the grow facility and monitoring bacterial levels. Beyond these practices, there is little that growers can do to inhibit the spread of E. coli, especially once an infection has taken to a crop in the facility or in areas where there are several grow facilities. 

CO2 Delivery Solutions’ Success Inhibiting the Spread of E. coli

CO2 Delivery Solutions has been demonstrated to inhibit the spread of E. coli by up to 99% in trials on pepper plants and Cannabis. CO2 Delivery Solutions dissolves and saturates CO2 gas into the water to form an aqueous CO2 solution that is misted on to plant leaves.  

The microdroplets create a thin aqueous film around the leaf surface isolating the leaf from the atmosphere. Gradient diffusion allows CO2 molecules to move into the leaf. This CO2 transfer occurs within 90 seconds and the moisture evaporates in minutes. Misting is done for a few seconds up to four times an hour during the light cycle.  

The inhibition of single-cell pathogens such as E. coli on plants is caused by the frequent aqueous CO2 misting. Aqueous CO2 is acidic therefore dropping the pH on the plant surface for a few seconds. Once the CO2 is transferred the pH rebounds back up towards neutral. This continual fluctuation in pH makes for an unfavorable environment for single-cell pathogens such as E. coli, powdery mildew, and others to thrive, thus inhibiting their growth and spread.  

View fullsize

This pH volatility process is 100% natural without the requirement for any chemical sprays. Increasing the efficiency of CO2 uptake in plants from using CO2 Delivery Solutions also increases and accelerates indoor and outdoor crop growth resulting in higher biomass yields, faster cycle time for more harvests and reducing crop loss, all adding to grower profitability and consumer safety.

Lettuce Grown Hydroponically in Northeast Ohio is Essentially ‘E. coli Proof’ So Go Back To Eating Salads

Burton Greenhouse Is Growing Virtually “E. coli Proof" Lettuce.

View fullsize

Crunchita lettuce, a romaine hybrid, is grown hydroponically to avoid E. coli contamination. (Source: WOIO)

View fullsize

By Jen Picciano | December 6, 2019

CLEVELAND, Ohio (WOIO) - The hydroponically-grown lettuce from Great Lakes Growers is essentially “E. coli proof,” thanks to a series of safeguards put in place by owner John Bonner.

So while the rest of the country is throwing out lettuce purchased elsewhere, their business is experiencing a massive uptick.

Demand for their products skyrockets amid widespread E. coli scares, like the nationwide one currently being blamed for more than 100 illnesses in 23 states.

“There is this massive swell of demand because everyone had to throw out all their romaine,” said Bonner.

Prices go up because the industry can’t meet the demand. But they’re trying.

“It’s creating a massive growth trend in our industry. We’ve doubled the size of the business since 2015, just doubled it again this year, about to finish up that, and we’re about to double it again this spring. The growth is really incredible,” he said.

Bonner said they’re growing 5 million heads and 4000,000 pounds of cut lettuce every year.

They’ll soon be adding two more acres to grow products similar to romaine, in response to the frequent recalls. All the while, they’re working diligently to ensure safe lettuce.

View fullsize

The nationwide E. Coli scare over romaine lettuce means many are turning to local, and hydroponic grown greens.

@GreatLakesGrowers is expanding to meet the massive demand for safer lettuce.

Story on Cleveland 19 News at 5.

They avoid E. coli contamination, by watering the roots from underneath through aluminum channels, not on the leaves itself which are consumed. And the roots are removed upon shipping, so Bonner said there’s very little chance anything could happen.

He says they closely monitor for bacteria levels in their recycled water.

“We have a system in place that virtually eliminates the risk of it. and we also do testing every week with a third party to verify that,” Bonner said.

They’re working to rise to the occasion, but it can’t happen overnight.

“Seed to sale” takes them 30-45 days.

US: BREAKING NEWS - Number of Romaine-Linked E. coli Infections Continues To Grow

View fullsize

DECEMBER 05, 2019

An additional 35 people have reportedly been infected with the outbreak strain of E. coli O157:H7 linked to Romaine lettuce harvested in the Salinas, CA, growing region. The number of people, now 102, was first reported as 40 when the Centers for Disease Control & Prevention issued an advisory Nov. 22 before increasing to 67 last week. A total of 58 hospitalizations have now been reported.

The number of states affected is now 23, and the latest date that one of these patients reports becoming ill was Nov. 18, meaning illness onset dates reported to date are prior to the public warning issued Nov. 22.

Epidemiologic, laboratory, and traceback evidence collected to date indicate that romaine lettuce from the Salinas growing region may be contaminated with E. coli O157:H7 and is making people sick.

The Centers for Disease Control & Prevention and public health and regulatory officials from several states are investigating the multi-state outbreak.

As a precaution, the CDC issued an advisory Nov. 22 warning consumers not to eat -- and retailers not to sell -- Romaine lettuce from the Salinas Valley. There have been no deaths reported.