RV: [BITES-L] bites Sep. 2/10
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bites Sep. 2/10
Fancy food does not mean safe food, NYC edition
Nuevo Folleto Informativo: Esté preparado para las tormentas
Beef recalled from ONTARIO retailer; people sick with E. coli O157
US: Investigation broadens in egg recall
US: Eggs' 'Grade A' stamp isn't what it seems
US: Cleaning the henhouse
US: The high cost of eggs
US: Supplier of feed ingredient linked to salmonella outbreak is inspected
Restaurant inspection plan calls for 'grades'
OHIO: Veal video prompts Costco comment
Researchers discover bacterial charity work
MASSACHUSETTS: Cranberry juice shows promise blocking Staph infections
Population dynamics of Escherichia coli inoculated by irrigation into the phyllosphere of spinach grown under commercial production conditions
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Fancy food does not mean safe food, NYC edition
02.sep.10
barfblog
Doug Powell
http://www.barfblog.com/blog/143910/10/09/02/fancy-food-does-not-mean-safe-food-nyc-edition
Grub Street New York reports the city's No. 1 restaurant, Le Bernardin, featuring celebrity Top Cheferer Eric Ripert, received 32 demerits (4 points above the C mark) on an inspection last Friday.
General Manager David Mancini says he's expecting a follow-up on the initial "courtesy inspection" in the next week or two and tells us, "As aggressive as the inspection was, I don't want to make any comment until they come back and reinspect us, and then I'll probably have a great deal of comment."
Failures in the current inspection included:
• cold food item held above 41º F (smoked fish and reduced oxygen packaged foods above 38 ºF) except during necessary preparation;
• raw, cooked or prepared food is adulterated, contaminated, cross-contaminated, or not discarded in accordance with HACCP plan;
• sanitized equipment or utensil, including in-use food dispensing utensil, improperly used or stored; and,
• plumbing not properly installed or maintained, anti-siphonage or backflow prevention device not provided where required; equipment or floor not properly drained, and ssewage disposal system in disrepair or not functioning properly.
Bon appetite.
http://newyork.grubstreet.com/2010/09/sacre_coeur_five-star_le_berna.html?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+nymag%2Fgrubstreet+%28Grub+Street+-+nymag.com%27s+Food+and+Restaurant+Blog%29
http://en.wikipedia.org/wiki/Le_Bernardin
http://barfblog.foodsafety.ksu.edu/blog/138031/08/02/17/fancy-food-does-not-mean-safe-food-whole-foods-and-golf-club-edition
http://barfblog.foodsafety.ksu.edu/blog/138050/08/03/02/fancy-food-isnt-safer-food-san-diego-edition
Nuevo Folleto Informativo: Esté preparado para las tormentas
01.sep.10
bites
Benjamin Chapman
Traducido por Gonzalo Erdozain
http://www.barfblog.com/blog/143914/10/09/02/nuevo-folleto-informativo-est%C3%A9-preparado-para-las-tormentas
Resumen del folleto informativo mas reciente:
- Huracanes y tormentas pueden causar cortes de luz y problemas con los alimentos
- Esté preparado y proteja sus alimentos
- Ponga un termómetro en su heladera y freezer
- Prepare conservadoras y esté al tanto de lugares donde pueda comprar hielo seco y hielo en bloque
Los folletos informativos son creados semanalmente y puestos en restaurantes, tiendas y granjas, y son usados para entrenar y educar a través del mundo. Si usted quiere proponer un tema o mandar fotos para los folletos, contacte a Ben Chapman a benjamin_chapman@ncsu.edu.
Puede seguir las historias de los folletos informativos y barfblog en twitter
@benjaminchapman y @barfblog.
Beef recalled from ONTARIO retailer; people sick with E. coli O157
02.sep.10
barfblog
Doug Powell
http://www.barfblog.com/blog/143911/10/09/02/beef-recalled-ontario-retailer-people-sick-e-coli-o157
The Canadian Food Inspection Agency (CFIA) warned the public last night not to consume the raw beef products described below because these products may be contaminated with E. coli O157:H7.
All cuts of raw beef, including but not limited to tenderloin, beef chunks and ground beef, sold on August 6, 2010 from Kabul Farms retail store located on the appropriately named Beverley Hills Drive in North York, Ontario, are affected by this alert. These beef products were wrapped at the store for sale on demand and may not bear a label indicating packing date, lot code, or a Best Before date. So that's helpful. Consumers are advised to check their home refrigerator or freezer if they have the affected beef products.
CFIA is aware of an E. coli O157:H7 illness outbreak in Ontario and is collaborating with a bunch of agencies but won't provide any information on how many got sick when and where, although does state the investigation is ongoing.
http://www.inspection.gc.ca/english/corpaffr/recarapp/2010/20100901e.shtml
US: Investigation broadens in egg recall
01.sep.10
Wall Street Journal
Alicia Mundy
http://online.wsj.com/article/SB10001424052748703882304575466020771861484.html
The criminal division of the Food and Drug Administration and the Justice Department have joined the probe of the Iowa farm at the heart of the recent egg recall linked to an outbreak of salmonella, according to FDA Commissioner Margaret Hamburg.
"There is a formal investigation going on that extends beyond the FDA inspections that are focused on farm practice," Dr. Hamburg told reporters Wednesday. "It is the case that an investigation is under way. We are pursuing it with our partners in law enforcement."
Dr. Hamburg declined to discuss details or to say whether Federal Bureau of Investigation agents have visited facilities of Wright County Egg, a major egg producer that recalled 380 million eggs in mid-August.
Wright spokeswoman Hinda Mitchell said FDA officials were at Wright on Tuesday, and she said she believed FBI agents were also present. A Justice Department spokeswoman declined to comment.
Some 1,470 cases of salmonella have been reported to federal health authorities since late spring.
US: Eggs' 'Grade A' stamp isn't what it seems
02.sep.10
Wall Street Journal
Alicia Mundy and Bill Tomson
http://online.wsj.com/article/SB10001424052748704791004575466014072143010.html
To some shoppers, the meaning of the "USDA Grade A" shield on egg cartons seems pretty obvious.
"It means that the rabbi's blessed this as kosher, right?" said Stephen Potter, an early-morning shopper at a Safeway store in Alexandria, Va.
"It means they've been checked. It's the quality seal. They're safe," suggested Susan Hergenrather, who was cruising the aisles at a Harris Teeter supermarket.
Wrong and wrong. The mark on the carton just means that the U.S. Department of Agriculture had a "grader" at an egg-packing facility who checked the eggs' size and color and made sure the shells weren't cracked, a USDA official said. Consumers "misunderstand" the shield, he said.
Ever since the recent nationwide salmonella outbreak sickened more than 1,000 people and led to the recall of more than a half-billion eggs, USDA officials have stressed that ensuring egg safety isn't their job. That task, they say, belongs to the Food and Drug Administration, which said Wednesday it is getting help from its criminal division and the Justice Department in looking at the farms at the center of the recall.
So what's the point of stamping egg cartons as Grade A? The USDA has two different missions. It does regulate some food safety, especially with meat, but it's also responsible for promoting American food here and abroad. The egg shield comes from the USDA's marketing side.
Egg makers don't have to put a USDA grade on their cartons, and some choose not to. But the USDA shield can help them charge more for their products.
US: Cleaning the henhouse
01.sep.10
New York Times
Nicholas D. Kristof
http://www.nytimes.com/2010/09/02/opinion/02kristof.html?_r=2&adxnnl=1&partner=rss&emc=rss&adxnnlx=1283422692-qPPE0Ny4Gohf4+sPW/4wiw
Columnist Kristof says the latest salmonella outbreak, underscoring the failures of industrial farming, and that while inspections of Iowa poultry farms linked to the salmonella outbreak have prompted headlines about infestations with maggots and rodents, the larger truth is: industrial agriculture is itself unhealthy.
Repeated studies have found that cramming hens into small cages results in more eggs with salmonella than in cage-free operations. As a trade journal, World Poultry, acknowledged in May: "salmonella thrives in cage housing."
Industrial operations — essentially factories of meat and eggs — excel at manufacturing cheap food for the supermarket. But there is evidence that this model is economically viable only because it passes on health costs to the public — in the form of occasional salmonella, antibiotic-resistant diseases, polluted waters, food poisoning and possibly certain cancers. That's why the president's cancer panel this year recommended that consumers turn to organic food if possible — a stunning condemnation of our food system.
US: The high cost of eggs
01.sep.10
New York Times
Nicolas Kristof
http://kristof.blogs.nytimes.com/2010/09/01/the-high-cost-of-eggs/
My Thursday column is about the cost of industrial farming practices. I'm thinking not so much the price we pay in the store but the price we pay in pollution, in antibiotic-resistant diseases and in food poisonings such as the salmonella outbreak now in the headlines. It's not so much eggs that sicken people with salmonella — it's industrial farming models.
As a kid who grew up on a farm and was very active in the FFA, let me say right off the bat that the problem isn't the typical farmers. It's these industrial operations that turn farms into meat factories. For example, United Egg Producers (the egg lobby) says that there are now a dozen companies with more than 5 million laying hens. Those are to the family farm what Wal-Mart is to a Mom-and-Pop store. This kind of intensive concentration is also harmful for rural America, creating a kind of modern feudalism (small number of rich proprietors and large number of much poorer workers) that are the end of small town America.
It's true that there are problems with all approaches to farming. Even cage-free operations, for example, find that they need to debeak hens because they cluster together. And free range operations in which chickens actually scratch around the grass for food take up vast amounts of space. United Egg Producers calculates that the land for such poultry operations (at 400 birds per acre) would add up to 740,000 acres, an area larger than Rhode Island.
In practice, many producers that call themselves "free range" really aren't. They may in theory offer birds a fenced run outside, but in practice the barn is structured so that most of the birds never go outside. Or the "free range" may consist of a bit of fenced concrete.
In the old days, salmonella often came from contamination on the outside of the egg. These days, egg washing has improved and that isn't the problem. The problem is that the hen, who seems healthy, is infected with salmonella in her ovaries, and so the egg has salmonella inside the shell. This is what seems far more common today in industrial egg operations than in traditional farms. The Humane Society of the United States, in an extensive report called "Food Safety and Cage Egg Production," suggests that in the 1940's, salmonella sickened only a few hundred Americans a year and that its spread was caused by the rise of industrial farming. The report also suggests that the egg industry's eradication of salmonella gallinarum (a kind that affects birds but not people) permitted the spread of salmonella enteritidis, the kind that affects humans but not birds — the kind in today's outbreak.
United Egg Producers will push back of course. It will say that 1 death a week is nothing in a country as big as the United States, and that cheap food is what consumers want. It will argue that moving to cage-free production will significantly add to costs. In fact, the industry's own estimate is that cage-free adds about 11.5 cents per dozen to costs, or a bit less than a penny per egg. My hunch is that that's a price worth paying, especially if it means less salmonella. In fact, the industry has pushed back at other safety measures, such as vaccination of hens — and that's why it's in this mess.
The CDC estimates that 2 percent of consumers eat a salmonella-tainted egg each year, but most don't get sick because the egg was fully cooked. The industry emphasizes, rightly, that consumers have to be educated to cook eggs thoroughly, and to wash hands after they have touched raw eggs. True. But as the Humane Society notes, Patricia Griffin of CDC offered the best retort to this blame-the-victim approach in the context of e. coli. She asked: "Is it reasonable that if a consumer undercooks a hamburger…their three-year-old dies?"
I welcome your comments
US: Supplier of feed ingredient linked to salmonella outbreak is inspected
02.sep.10
Des Moines Register
Philip Brasher
http://www.desmoinesregister.com/article/20100902/BUSINESS/9020337/1029/Supplier-of-feed-ingredient-linked-to-salmonella-outbreak-is-inspected
Federal inspectors are investigating the Minnesota rendering operation that supplies an ingredient used in hen feed at the Iowa egg farms linked to the national salmonella outbreak.
Central Bi-Products, part of Farmers Union Industries, produced meat and bone meal that tested positive for salmonella at a feed mill operated by Quality Egg LLC in Galt, Ia.
Don Davis, president and chief executive of Farmers Union Industries, said Wednesday that Food and Drug Administration inspectors visited his offices in Redwood Falls, Minn., on Tuesday and are looking over the plant in Long Prairie that produced the bone meal. "They ask a lot of questions, take a lot of notes," he said.
Davis said he's confident the bone meal was free of salmonella bacteria or other pathogens when it left his company. Central Bi-Products processes dead livestock and poultry into bone meal and other products. Bone meal is used as a mineral supplement in feed.
Carcasses are cooked at 260 to 285 degrees under high pressure to remove water from the product and to separate fat from the protein. "In the process, all known pathogens are killed," he said.
Davis said the products are periodically tested for salmonella and have been free of the bacteria.
Restaurant inspection plan calls for 'grades'
02.sep.10
Pittsburgh Post-Gazette
Patricia Sabatini
http://www.post-gazette.com/pg/10245/1084377-28.stm
The Allegheny County Board of Health received a draft proposal Wednesday for plans to assign area restaurants grades based on their annual inspections and post the results prominently in restaurant windows.
Under the proposal, food inspectors would use a numerical scoring system starting at 100 percent and subtracting points for any food safety violations they uncover. The more serious the violation, the higher the deduction. Repeat violations also would draw higher deductions. Restaurants could score as high as 110 percent by earning extra credit for exceeding standards.
Under the current system, inspectors record violations but do not issue an overall grade or score.
"This puts some objective criteria on what has been more subjective in the past," health department director Bruce Dixon told the board.
Many details under the new program were still being worked out, such as whether restaurant owners who are unhappy with their grades will be required to pay for a reinspection, said Steve Steingart, acting director of the food safety program, who presented the proposal.
It also hasn't been decided whether grades, scores or both would be displayed publicly in restaurant widows, Mr. Steingart said.
OHIO: Veal video prompts Costco comment
02.sep.10
Meatingplace
Lisa M. Keefe
http://www.meatingplace.com/MembersOnly/webNews/details.aspx?item=18252
Costco released a statement Wednesday in response to a video of veal calves in individual crates on an Ohio farm, made surreptitiously by a group called Mercy for Animals (MFA) and teed up as cruel and inhumane treatment of the animals.
The video singled out Costco and Giant Eagle as carrying the farm's branded products. In a release, Costco CEO Jim Sinegal says, "The company had not been aware of the issue before we saw the video. We are extremely disappointed, not only with the performance of our supplier in this instance, but with our own performance as well."
In fact, the farm in question, Buckeye Veal Farm in Apple Creek, Ohio, said Monday that it already had phased out most of the individual crate housing shown in the video in favor of group housing, and was continuing the process with the animals that remained in crates, according to a report in The Daily Record in Wooster, Ohio.
In any case, an agreement reached in June between the new Ohio Livestock Care Standards Board, authorized by a voter referendum late last year, also calls for phasing out veal crates. MFA is pressuring the board to move up the timeline for that to happen, The Daily Record reports.
On its website, MFA asks consumers to adopt a vegan diet, urge Costco and Giant Eagle to stop selling veal, urge the Ohio Livestock Care Standards Board to "honor the common-sense agreement reached in June," spread the word via social media, and make a donation to the group.
Researchers discover bacterial charity work
01.sep.10
HHMI
http://www.hhmi.org/news/collins20100901.html
In the war against antibiotics, bacteria aren't selfish. According to a new report from Howard Hughes Medical Institute (HHMI) researchers, a handful of resistant pathogens can protect an entire colony.
Prevailing wisdom held that antibiotic resistance works only on an individual level: a bacterium acquires a genetic mutation that confers protection against a drug, allowing it to survive and reproduce. Eventually, as vulnerable bacteria die, the mutant's stronger progeny repopulate the colony.
But the new study, published September 2, 2010, in the journal Nature, reveals that there are also population-wide changes in the bacterial community at work. Under the onslaught of an antibiotic, resistant Escherichia coli produce—at an energy cost to themselves—a protein that seeps into the communal broth and triggers a slew of protective mechanisms in their non-resistant neighbors.
In the past few years, the rise of 'super bugs' such as MRSA (methicillin-resistant Staphylococcus aureus) has had hospitals and medical professionals scrambling to fend off a public health disaster. The new findings could help explain why resistance has been so difficult to curb, the researchers say.
HHMI investigator James J. Collins and colleagues at Boston University grew bacteria in a bioreactor—a large, capped glass vessel with many extended arms that allow researchers exquisite control over what the bugs are exposed to. "It kind of looks like a component of a moonshine factory out in the backwoods," Collins says.
Interested in how genetically identical E. coli acquire mutations that confer resistance, the researchers trickled the antibiotic norfloxacin into the bioreactor. As they upped the bugs' exposure, the scientists periodically removed samples of bacteria and measured their 'minimum inhibitory concentration', or MIC—the minimum strength of drug that stops growth of the bug. Larger MICs indicate higher antibiotic resistance.
"That's when we were stopped in our tracks," Collins says. To their total surprise, the researchers discovered that the MIC of individual samples was much lower than the MIC for the population as a whole. Upon further digging, they found that bacterium with high MICs were few and far between—typically making up less than one percent of the population.
The team then analyzed the proteins made by high-MIC bacteria in the presence of norfloxacin, and discovered that an enzyme called tryptophanase was particularly abundant. Tryptophanase breaks down the amino acid tryptophan into smaller components. One of its products is indole, a signaling molecule that E. coli produces under certain stressful conditions.
It turns out that indole offers vulnerable bacteria two kinds of protection against norfloxacin. One is to turn on cellular machines that pump the antibiotic out of the cell, as if expelling a poison. The metabolite also turns on pathways that protect the cell from oxidative stress, a chemical imbalance that leads to the build up toxic molecules called free radicals. A few years ago, Collins's team reported that antibiotics work, in effect, by pummeling bugs with free radicals. "Here we're seeing that indole is dampening that—turning on the sprinklers for the fire resulting from the antibiotics," he says.
By comparing the growth of bacteria, the researchers found that the mutants produce indole at a significant cost to themselves. "They don't grow as well as they could, because they're producing indole for everybody else," Collins says.
This altruistic behavior—which appears in species throughout the animal kingdom, including humans—presents a well-known paradox for evolutionary biologists: if evolution favors the fittest, why would an individual sacrifice its own fitness for the rest of the group?
Collins's findings bolster the 'kin selection' theory – formalized in the 1960s by the British evolutionary biologist W.D. Hamilton -- that says that organisms may behave altruistically toward others that share their genes. So even if altruistic behavior prevents an individual from surviving to pass its own genes on to future generations, others in the population can fulfill that evolutionary role. In this case, the E. coli were from the same population, so by producing indole, the resistant mutants were protecting their own gene pool.
Though the study may make waves in the evolutionary biology field, Collins thinks its implications are most pertinent for public health. The researchers confirmed that the same population-wide protection occurs when bugs are exposed to other kinds of antibiotics. What's more, many types of bacteria produce indole, suggesting that a similar cooperative process may happen in a host of bacterial species.
Future research on antibiotics might well focus on targeting the indole pathway as a means to block bugs' ability to share resistance, Collins says. More broadly, the work highlights the pressing need for investment in new antibiotic development.
"The chance that we'll have new and dangerous super bugs emerging is quite high, and I'm worried that our arsenal of antibiotics is dwindling," Collins says. "We have time to respond now, but we need a movement backed by political will to expand antibiotic research and development."
MASSACHUSETTS: Cranberry juice shows promise blocking Staph infections
01.sep.10
Worcester Polytechnic Institute
Michael Cohen
http://www.eurekalert.org/pub_releases/2010-09/wpi-cjs090110.php
WORCESTER, Mass. -– Expanding their scope of study on the mechanisms of bacterial infection, researchers at Worcester Polytechnic Institute (WPI) have reported the surprise finding from a small clinical study that cranberry juice cocktail blocked a strain of Staphylococcus aureus (S. aureus) from beginning the process of infection.
The data was reported in a poster presentation at the American Chemical Society's national meeting in Boston on August 23, 2010, by Terri Camesano, professor of chemical engineering at WPI. "Most of our work with cranberry juice has been with E. coli and urinary tract infections, but we included Staphylococcus aureus in this study because it is a very serious health threat," Camesano said. "This is early data, but the results are surprising."
The virulent form of E. coli that Camesano studies is the primary cause of most urinary tract infections. Strains of S. aureus can cause a range of "staph infections" from minor skin rashes to serious bloodstream infections. One particular strain, known as Methicillin-resistant Staphylococcus aureus, or MRSA, is a growing public health problem in hospitals, nursing homes, and other institutions because it doesn't respond to most antibiotics.
To cause an infection, bacteria must first adhere to a host, then gather together in colonies to form a biofilm. In the current study, Camesano recruited healthy female students at WPI to drink either cranberry juice cocktail or a placebo fluid that looked and tasted like cranberry juice. The subjects provides urine samples at prescribed intervals after drinking the juice or placebo, and those samples were incubated in petri dishes with several strains of E. coli and a single strain of S. aureus. Camesano's team stained the bacteria with a special dye, then used a spectrophotometer to measure the density of the bacterial colonies in the dishes over time. Their analysis showed that the urine samples from subjects who had recently consumed cranberry juice cocktail significantly reduced the ability of E. coli and S. aureus to form biofilms on the surface of the dishes.
"What was surprising is that Staphylococcus aureus showed the most significant results in this study," Camesano said. "We saw essentially no biofilm in the staph samples, which is very surprising because Staph aureus is usually very good at forming biofilms. That's what makes it such a health problem."
With E. coli, Camesano's focal point is the small hair-like projections known as fimbriae, which act like hooks and help the bacteria latch onto cells that line the urinary tract. Camesano has shown that exposure to cranberry juice causes the fimbriae on E. coli to curl up, blunting their ability to attach to cells. S. aureous, however, doesn't have fimbirae, so there must be other reasons why the cranberry juice affected its biofilm formation in the study. "These results do create more questions than answers," Camesano said. "We believe this is an important new area to explore, and we are now thinking about how best to proceed."
Since bacterial adhesion is required for infection, Camesano hopes that better understanding of the specific mechanisms and forces involved in biofilm formation will help inform future studies aimed at identifying potential drug targets for new antibiotics. The data may also be useful in studies aimed at engineering the surfaces of invasive medical devices like catheters to make them more resistant to bacterial adhesion.
The research detailed in the current study was supported by grants from the Cranberry Institute and the Wisconsin Cranberry Board.
About Worcester Polytechnic Institute
Founded in 1865 in Worcester, Mass., WPI was one of the nation's first engineering and technology universities. Its14 academic departments offer more than 50 undergraduate and graduate degree programs in science, engineering, technology, management, the social sciences, and the humanities and arts, leading to bachelor's, master's and PhD degrees. WPI's world-class faculty work with students in a number of cutting-edge research areas, leading to breakthroughs and innovations in such fields as biotechnology, fuel cells, information security, materials processing, and nanotechnology. Students also have the opportunity to make a difference to communities and organizations around the world through the university's innovative Global Perspective Program. There are more than 25 WPI project centers throughout North America and Central America, Africa, Australia, Asia, and Europe.
Population dynamics of Escherichia coli inoculated by irrigation into the phyllosphere of spinach grown under commercial production conditions
01.sep.10
International Journal of Food Microbiology
J.D. Wood, G.S. Bezanson, R.J. Gordon and R. Jamieson
http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T7K-50X3TP0-1&_user=10&_coverDate=08%2F31%2F2010&_rdoc=1&_fmt=high&_orig=search&_origin=search&_sort=d&_docanchor=&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=1018ad4f97d1c07e516c0fd73fcf5a71&searchtype=a
Abstract
Recent outbreaks of food-borne illnesses associated with the consumption of fresh produce have increased attention on irrigation water as a potential source of pathogen contamination. A better understanding of the behaviour of enteric pathogens introduced into agricultural systems during irrigation will aid in risk assessments and support the development of appropriate farm-level water management practices. For this reason, the survival dynamics of two nalidixic acid resistant strains of Escherichia coli after their spray inoculation into the phyllosphere and soil of field spinach were examined over two growing seasons. E. coli strains NAR, an environmental isolate, and DM3n, a non-pathogenic serotype O157:H7, were applied at rates of 104 to 107 cfu/100 ml to the fully developed spinach plants that arose subsequent to the harvesting of their upper leafy portions for commercial purposes (secondary growth plants). After 72 h, E. coli on spinach were reduced by 3-5 logs. Culturable E. coli were recovered from plants up to 6 d post-inoculation. Survival in soil was greater than in the phyllosphere. Under ambient conditions, the mean 72 h first order decay constant computed by Chick's Law was 0.1 h-1. Although light reduction studies indicated UV irradiation negatively influenced the persistence of E. coli, a simple relationship between UV exposure and phyllosphere E. coli densities could not be established. E. coli introduced to the leafy portions of spinach via spray irrigation displayed rapid declines in their culturability under the open environmental conditions experienced during this study. A 6 d period between the last irrigation and harvest would minimize the risks of E. coli survival in the spinach phyllosphere. E. coli NAR was identified as a possible surrogate for the O157:H7 strain, DM3n.
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