Saturday, December 29, 2007
I’ll be back at the end of January with a notebook full of blog topics, which I hope you’ll find interesting.
A happy and food-safe New Year to all.
The company, which was shut down early in December due to a Salmonella outbreak, has been under close scrutiny by the Singapore health authorities. The government monitored Prima's clean up and its restart, taking samples of all raw ingredients and finished products. It has concluded that Prima now meets all appropriate food safety standards.
Now, if only the cakes were calorie-free!
Yesterday, the Massachusetts Department of Public Health announced that four cases of listeriosis (infection due to Listeria monocytogenes) had been traced to pasteurized milk produced by Whittier Farms of Shrewsbury, MA. The 4 victims included 3 elderly people and one pregnant woman. Two of the four have died.
Whittier Farms has voluntarily suspended all operations until the source of the Listeria contamination can be found and removed.
In an earlier post, I stated that one of the reasons to avoid drinking raw milk or eating dairy products made from unpasteurized milk was the risk of contracting Listeria monocytogenes. But what, you might well ask, is this heat-sensitive pathogen doing in pasteurized milk? There are several possibilities, all of which I am sure will be thoroughly checked by the State inspectors and by the company.
1. Faulty pasteurization. An equipment malfunction could result in underpasteurization, either by reducing the length of time the raw milk is heated, or by lowering the temperature at which it is pasteurized. This could allow Listeria monocytogenes to survive, along with other bacteria. But, according to a report in yesterday’s Boston Globe, the pasteurizer was working correctly.
2. Ingredients added after pasteurization. Adding an ingredient, such as a vitamin supplement or a flavoring, to the milk after it has been pasteurized could be a source of the Listeria monocytogenes.
3. Cross-contamination. A faulty pipe connection or a leak in a valve, a heat exchanger, or a pipe might allow raw milk to re-contaminate the pasteurized milk before the milk is bottled.
4. Inadequate sanitizing of processing and packaging equipment. Inadequate cleaning and sanitizing of the pipes and valves through which the pasteurized milk travels could allow Listeria monocytogenes to build up in the system and contaminate the pasteurized milk.
5. Inadequate cleaning and sanitizing of bottles. Whittier Farms is one of the few dairies that still use glass bottles. These bottles must be washed and sanitized before filling.
Listeria monocytogenes usually causes nothing more than mild symptoms in healthy adults, but can produce a severe, even deadly, illness in young children, the elderly, the immunocompromised, pregnant women and their unborn children.
Friday, December 28, 2007
First, let’s talk turkey. Unless you have spent the last few decades living in an isolation booth, you must know that by USDA’s own admission, 20-25% of raw ground turkey meat is contaminated with Salmonella. Yet your recipe directions do not provide for a reliable “kill” step. For example, your “Whole-wheat spaghetti and turkey meatballs” recipe directs the reader to prepare the meatballs as follows:
“In a skillet, heat 1 tablespoon olive oil over medium high. Cook 20 frozen Light Turkey Meatballs until browned, 5 to 7 minutes. Add 1 1/2 cups store-bought marinara sauce and 1/2 cup water: Cook until heated through, 5 minutes.”
These instructions leave too much to the reader’s imagination. Browning alone is not enough to cook the meatballs completely, and “heated through” can mean different things to different people. Starting with hard-frozen meatballs increases the risk that the center of the meatballs won’t reach 165ºF, which is the “safe” temperature recommended by USDA.
I also take strong exception to your instructions for cooking chicken in the microwave. Microwave cooking is a notoriously unreliable way to kill bacteria, especially in a solid piece of meat such as a chicken breast. Customers who purchased ConAgra’s Banquet pot pies found that out the hard way. Cooking the chicken breasts until the meat is “...just opaque throughout...” is not a guarantee of microbiological safety.
A few weeks ago, when I was browsing eggnog recipes on-line, I came across yours. It sounded very tasty, but also very risky. It was completely inappropriate for you to publish a recipe that called for raw eggs without adding at least a precautionary statement about the possibility that the eggs might contain Salmonella Enteritidis. You could easily have recommended that pasteurized eggs be used in the recipe.
According to (now 10 year old) data from the US Centers for Disease Control and Prevention, there are approximately 76 million cases of food-borne disease in the US every year. That is more than one case of food-borne illness for every four people in this country every year. It is time that you, and others like you, shouldered some responsibility for teaching the public how to cook meals that are not only tasty and nutritious, but also are microbiologically safe.
Phyllis Entis, MSc., SM(NRM)
Food Poisoning In Hong Kong: Ten men reported symptoms of food poisoning, including nausea, vomiting, diarrhea and abdominal pain. The symptoms began between 1 and 6 hours after the men had eaten turkey purchased from a restaurant. The turkey was purchased on December 26th, and eaten on December 27th. The report makes no mention of how the 10 men stored the cooked turkey.
Don't Always Blame Bacteria: Kidney beans contain a natural toxin, known as lectin, which is inactivated by cooking - something that 248 students in Yunnan Province of China may have found out the hard way. Their school lunch included kidney beans, which authorities suspect were undercooked. The students, who suffered bouts of nausea and vomiting as a result of the meal, are all expected to recover.
Let Them Eat Cake Again: The Singapore bakery chain, Prima Food, which closed early in December due to an outbreak of Salmonella, has been allowed to conduct a trial production run. The trial run is being closely monitored by the local health authorities, who are taking samples at every step of the process and analyzing the samples in the government labs.
When they discovered the theft, the company notified USDA. The agency has issued a public health alert, which provides details of the establishment number, lot numbers, and packaging. If you have purchased any of ground beef described in the USDA notice, please discard it or return it to the store.
Thursday, December 27, 2007
The outbreak began on December 19th and, by December 27th, had affected 34 residents and 2 workers at the facility. Norovirus was found in a stool sample from one of the victims of the outbreak.
Norovirus is a particular problem in places where a large number of people congregate in a relatively confined area. Nursing homes, daycare centers, hotels, restaurants and cruise ships have all been venues for outbreaks of gastroenteritis caused by this virus.
People visiting, living in, or working in these environments should pay particular attention to personal hygiene - especially the need to wash their hands frequently, and especially before handling food or touching their own or anyone else's face.
According to the outbreak report released to him by the State of North Carolina, 27 out of 110 guests (and an unreported number of workers) at a catered wedding reception took home something more than a piece of wedding cake. They received a dose of E. coli O157:H7 with their wedding feast.
The epidemiological investigation, the results of which are provided in detail in the full report, pointed to London Broil as the most probable source of the pathogen. This could not be confirmed, since there was no left-over meat to test. And the source of the meat could not be traced, because there was no record of the original producer. The final paragraph of the report states, in part, that
"The association between London Broil flank steaks and the outbreak was reported to the North Carolina Department of Agriculture, and a compliance officer from that agency examined the invoices and other records the caterer had regarding those steaks. The invoice information indicated who the distributor for the product was, but there were no records available to identify the original producer for the meat. Therefore it is impossible to complete traceback for the item, or to identify unopened product that could be tested."So, once more, the consumer was treated as the canary in the cage. Proper record keeping would have allowed investigators to identify the source of the meat and request a recall, if appropriate. Instead, all that North Carolina could do was post the "fingerprint" of the offending E. coli O157:H7 in the national data base and wait for a match. As of November 29th, the date of the final report, this appears to have been an isolated incident.
A download link to obtain the full report is available at Marler Blog for those who are interested in the details. Thanks, Bill, for making this available.
Wednesday, December 26, 2007
The recall covers institutional-sized (6 pound, 5 ounce) cans of GFS "Fancy Blue Lake Cut Green Beans". The product was distributed to restaurants and food service operators in eleven states. In three of those states - Tennessee, Indiana, and Kentucky - the recalled product was also available at retail through GFS Marketplace stores.
Symptoms of botulism can appear as soon as 6 hours or as late as 2 weeks after eating food that contains the toxin. Please read the FDA recall notice for details on the recall and for a description of the symptoms of botulism.
Maramont Corporation, of Brooklyn, NY is recalling broiled beef patties that were produced on December 18th. Routine testing by FSIS at Maramont's facility detected the presence of Listeria monocytogenes, but not until the patties had already been shipped to Jersey City, NJ schools. The patties are meant to be heated in a microwave before serving, but there is no guarantee that microwaving will eliminate the Listeria.
If your child attends a school in Jersey City and has eaten a "broiled hamburger" at school in the last week, please be on the alert for any sign of illness and report this to the school and to the appropriate health authorities.
This is just one more example of the barn door being locked after the cows have fled. With the variety of relatively inexpensive rapid testing kits available to the food industry, there is no longer any excuse for shipping food products before screening for pathogens such as Salmonella, E. coli O157:H7 and Listeria monocytogenes.
Tuesday, December 25, 2007
This is the first article in my “Hope or Hype?” series. I’ll be monitoring new product releases that relate to food safety issues and, from time to time, I’ll give you my opinion, based on the available scientific information, as to whether or not the product claims are reasonable.
The Hype: The January 7, 2008 issue of Forbes magazine profiled an ozone generator, and the company that developed it, under the headline “The Ozone Solution. Purfresh aims to capitalize on E. coli scare stories by cleaning up fruits and vegetables”. The article described Purfresh’s equipment, which is used to produce ozone for produce sprayers and cold storage rooms.
The article’s headline implied that the Purfresh process is being used for both fruits and vegetables. Yet, all of the examples in the article described its use by fruit growers and packers. I wondered about this, and decided to see what studies have been carried out on the effectiveness of ozone treatment for eliminating pathogens from other produce such as lettuce or baby spinach.
I found several research articles, all of which confirmed that ozonated water is more effective than plain water. But the results were variable. A study-to-study comparison of performance was complicated by differences in the test conditions - ozone concentration, length of contact, water temperature and type and quantity of microbial contaminant - used in the various studies.
In a study of the effect of ozonated water on the bacterial levels in fresh-cut lettuce, rinsing the lettuce with ozonated water reduced the bacterial counts by roughly 95%, and extended the shelf life of the lettuce. That remaining 5% of the bacterial population, however, could still include pathogens such as Salmonella or E. coli O157:H7.
The effect of ozonated water on bacteria is very much dependent on the length of contact time. In a study of strawberries and raspberries that had been deliberately contaminated with Salmonella or E. coli O157:H7, researchers were able to kill approximately 99.9% of the bacteria. But it took more than one hour of soaking to do so.
The Bottom Line: Ozonated water was as effective as chlorinated water in most situations. And when ozone decomposes, it leaves no toxic byproducts behind in the food. But, while an ozonated water rinse can reduce overall bacterial levels and improve the shelf-life of fruits and vegetables, it cannot guarantee that the produce will be pathogen-free. Ozonation may be an improvement over chlorination, but it’s not a panacea.
Monday, December 24, 2007
The "PhysiCAL No Fat Milk", sold in 2-liter plastic bottles is from the end of a production run and has a "use-by" date of January 5, 2008. The processor, Parmalat Australia Limited, warns that this milk could cause nausea or vomiting if consumed.
The magazine reports that more than 60% of consumers say that they thaw their frozen food in the refrigerator, and the majority of consumers know that poultry should be cooked to an internal temperature of 165ºF. But 63% of those surveyed admitted that they rarely, if ever, used a meat thermometer, and one third claimed to be able to tell that meat was "done" simply by looking at it.
Government agencies and food safety educators spend a great deal of time and effort trying to "get the message out". While they appear to be having some degree of success, the next question is how to get consumers to implement that information.
For starters, here are a few reminders for a food-safe holiday season.
1. Use a meat thermometer when roasting your holiday turkey. You can find details at the USDA web site, and in my blogs of November 23rd and December 12.
2. Use pasteurized eggs to prepare your eggnog, or choose a recipe that includes a cooking step to prevent the possiblity of Salmonella in your eggnog. Remember, there isn't enough alcohol in the eggnog to kill Salmonella.
3. Always clean up very thoroughly after handling or preparing raw meat, eggs or poultry. Remember that Salmonella, Campylobacter and other microbes can be transferred from sponges, dishrags, countertops, sink faucets and the handles of knives and utensils - not just cutting boards.
4. Thaw frozen food in the refrigerator, not at room temperature.
5. Cool cooked food quickly - in the refrigerator, not on the countertop. Your refrigerator can handle the load. Do not try to cool the food in large, deep batches. Spread it out in a shallow layer in several containers, if necessary, to cool it rapidly. Then, once the food has cooled, you can consolidate it into a single container.
If you have any tips of your own to add, or questions about safe handling, please post a comment.
Have a happy and safe holiday!
Sunday, December 23, 2007
This being a quiet news day (no recalls announced this morning, for a change), I decided to delve into some numbers. Here's what I found.
- The Centers for Disease Control and Prevention (CDC) estimates that there were 12.71 cases of Campylobacter and 14.81 cases of Salmonella per 100,000 people in the United States in 2006.
- The Food Standards Agency reports a total of 53,052 lab-reported cases of food-borne diseases for the year 2005. This translates to 88.4 cases per 100,00 people in the UK that year. The numbers for 2006 are not yet available.
- Overall, the European Union (EU) suffered 5710 outbreaks of food-borne disease in 2006, 0r 1.16 per 100,000 people. This total includes more than 175,000 cases of Campylobacter infection, and more than 160,000 cases of Salmonella, for a total of 68.2 cases due to these two pathogens per 100,000 people.
- Canada reported 106 food-borne disease outbreaks in 2005, or 0.35 per 100,000 people. There were 19.6 reported cases of Salmonella and 29.9 reported cases of Campylobacter per 100,000 people.
Official government statistics are based on reported incidents. This is not a reliable number, because it is based only on those victims who visited a doctor or emergency room. A visit to a doctor's office can be an expensive proposition in the U.S. for the more than 15% of the population that is without health insurance. And co-pay policies and waiting times in countries with universal health care affect a person's decision go to the "bother" of seeking medical attention for what is a relatively mild illness. Country-to-country comparisons of unadjusted food-borne disease statistics are misleading.
In 1999, US researchers estimated that more than one person in every four (more than 25%) suffered an incident of food-borne illness each year, for a total estimate of 76 million cases annually. That same year, British researchers estimated that country's annual food-borne illness rate at one person in every five (20%). Until more recent data demonstrate that this relative performance has changed, the US accurately cannot claim the title of "world's safest food supply".
Saturday, December 22, 2007
Victims of norovirus infection suffer from vomiting, nausea and copious, watery diarrhea. The virus is very hardy, and survives for days on dry surfaces. It is usually spread through direct or indirect contact with contaminated vomit or feces.
To protect yourself from contracting a norovirus infection, pay special attention to personal hygiene. If you are spending time in public areas - hotels, restaurants, department stores, nursing homes, childcare centers, cruise ships or movie theaters - be careful to avoid touching your hands to your face at any time. Wash your hands frequently and thoroughly, using plenty of soap and hot running water.
Now, some Danish researchers have come up with a low-tech, inexpensive way to reduce the incidence of Campylobacter in poultry houses. They simply installed fly screens on all the ventilation openings. As a result, the percentage of Campylobacter-infected flocks of poultry dropped from 51% to 15%. While screening the ventilation openings in poultry houses isn't the complete answer to controlling Campylobacter, it's certainly a big help.
It's common knowledge that flies carry diseases. Isn't it nice that someone has applied that knowledge effectively?
Friday, December 21, 2007
The 6 lb. 5 oz. cans are labelled as "GFS Fancy Blue Lake Cut Green Beans", and carry the lot number 19H7FL. The product was sold in GFS Marketplace stores in Tennessee, Indiana and Kentucky.
Clostridium botulinum toxin can be fatal. Do not take any chances with this product.
North Carolina's Department of Health and Human Services is reminding parents that giving a pet turtle to their kids is not a good idea.
Four children were recently confirmed to have suffered from a Salmonella infection last summer, and one of them was hospitalized due to kidney failure. But they didn't become infected from food. Baby pet turtles were the source of the infection. Veterinarians tested the turtle belonging to one of the infected children, and found the identical strain of Salmonella to the one recovered from the sick child.
Pet turtles have long been a source of occasional Salmonella illnesses in children. Health agencies warn about this over and over again. In fact, the FDA banned the sale of these turtles more than 30 years ago - in 1975. Unfortunately, some of these are still finding their way into the hands of children. And the Salmonella that they carry is finding its way from the children's hands into their bodies.
Please be warned. Pet turtles and children - especially young children - are not a good combination.
This is the most recent in a series of recalls of Salmonella-contaminated sesame seeds that have taken place in the UK and Canada this year.
Salmonella infections can produce symptoms of diarrhea, cramps, mild fever, nausea and vomiting, which may last for several days. Depending on the age and health of the victim, the quantity and strain of Salmonella present in the contaminated food, and the amount and type of food, symptoms can vary from mild to severe; some victims might require hospitalization.
The outbreak appears to have begun last July in Sweden, where 177 cases of Salmonella Java infection have been confirmed. Many of the victims (more than 40% of the first 116 cases) required hospitalization. Traceback of consumer information led Swedish authorities to conclude that baby spinach imported from Italy was the source of the Salmonella. The baby spinach had been sold both as a single green and in a package of mixed greens.
Unfortunately, the Swedish investigators were unable to detect Salmonella in any of the suspect baby spinach. Nevertheless, Sweden issued an alert through the EU's Rapid Alert System for Food and Feed (RASFF) on August 24th.
Since then, the identical strain of Salmonella has been responsible for 50 illnesses in other European countries, including Denmark, the Netherlands, Finland, Norway and the UK. Epidemiological investigations in the UK determined that many of the victims in that country had eaten mixed greens salads. While no other food has been identified as a probable source of the outbreak, no one has yet been able to confirm by lab tests that the baby spinach was the culprit.
The EU has assessed this outbreak as a "...continuous and sustained risk to human health..." and is encouraging national health agencies to be on the alert. There will surely be more cases, so if you live in - or are planning to travel to - one of the affected countries, please avoid the spinach and the mixed green salads.
Thursday, December 20, 2007
The USDA Food Safety and Inspection Service has just issued a public health alert. The outbreak of illnesses caused by a multi-drug resistant Salmonella Newport has been linked to ground beef products that were ground and sold in Safeway supermarkets between September 19th and November 5th. Anyone who purchased fresh ground beef from Safeway stores in California, Arizona, Nevada, Hawaii and New Mexico between these dates should discard or destroy it.
To date, 38 cases of salmonellosis have been tied to this meat.
Australia, Dec 20th:
"Probe after kids fall ill with suspected food poisoning"
Marion County, Indiana, Dec 18th:
"Marion County Health Officials Issue Shigellosis Alert"
Mumbai, India, Dec 20th:
"Mumbai milk 'poisoned children' "
UK, Dec 19th:
"Pupils hit by Salmonella bug"
Yunnan, China, Dec 17th:
"Four Chinese Pupils Dead From Suspected Food Poisoning"
Reason #5. Staphylococcus aureus
This toxin-producing microbe can infect cow udders. A cow with an infected udder will shed S. aureus in its milk. If the milk is not cooled immediately, or if the raw milk is used to make cheese, the bacteria can multiply and produce toxin.
Reason #4. E. coli O157:H7 and other pathogenic E. coli
E. coli is a normal inhabitant of the intestine. While E. coli O157:H7 gets most of the media attention, there are a number of strains that can be carried by apparently healthy cattle and can cause disease in humans. Unless scrupulous care is taken during milking, pathogenic E. coli can get into the milk. It takes only a few live cells of some of these strains to make a person - especially a child - extremely sick.
Reason #3. Listeria monocytogenes
One of the earliest recognized outbreaks of listeriosis resulted from eating contaminated Mexican-style cheese that had been made using unpasteurized milk. This 1985 outbreak was responsible for 142 illnesses and 48 deaths, including several miscarriages.
Reason #2. Salmonella
Raw milk has been the confirmed source of numerous Salmonella outbreaks. One of the more recent occurred in Pennsylvania in February of 2007. Twenty-nine individuals suffered from Salmonella gastroenteritis as a result of drinking unpasteurized milk, or eating dairy products made from unpasteurized milk produced at a single Pennsylvania dairy. Two of the 29 victims landed in the hospital. Fortunately, no one died in this outbreak.
Reason #1. Campylobacter
Washington State has just issued a recall alert for raw milk contaminated with Campylobacter jejuni. This species, along with Salmonella, is one of the two most common causes of food-borne disease in the U.S. and Canada.
Got (Pasteurized) Milk?
The FDA has also announced a recall of "Dried Roach" uneviscerated fish due to the risk of Clostridium botulinum. This product of Latvia was imported by Royal Seafood Baza Inc. and distributed through Net Cost Market stores in Philadelphia, PA and in Brooklyn and Staten Island, NY. Sale of uneviscerated fish is illegal in New York State, due to the elevated risk of Clostridium botulinum in this food.
Wednesday, December 19, 2007
Reason #10. Rabies
Rabies is usually present in the saliva of an infected animal and is transmitted by a bite. But there is some question as to whether rabies might also be present in milk. In the 1990’s a total of 88 people in Massachusetts received rabies vaccine treatment after drinking raw milk from a cow that later was diagnosed with rabies.
Reason #9. Mycobacterium tuberculosis and M. bovis
These bacteria can be transmitted in the milk of infected cattle and cause tuberculosis.
Reason #8. Mycobacterium paratuberculosis
This species causes Johne’s disease in cattle and is believed to trigger Crohn’s disease.
Reason #7. Chronic Diarrhea Syndrome (Brainerd's Disease)
It’s not always possible to figure out what causes a disease. In 1983-84, more than 120 people in Brainerd, Minnesota were afflicted with chronic diarrhea lasting at least one year for many of them. While the precise cause of the illness was never discovered, the cases were clearly linked to raw milk from a single dairy. Other outbreaks of this syndrome have been reported since the 1980s - always linked to drinking raw milk or untreated water. The cause is still a mystery.
Reason #6. Brucella abortus
This pathogen has been mostly, but not completely, eradicated from cattle in the U.S., Canada and many other developed countries, thanks in part to the development of a vaccine and to the culling of diseased cattle. Unfortunately, it remains a serious problem in many less-developed countries in Africa, Asia, and Latin America, including Mexico. Undulant fever, which is transmitted in the milk of infected cattle, is a long-term, chronic disease that is difficult to treat and is known to cause miscarriages. The bacteria are killed by pasteurization, but are very content to survive in cheeses made from unpasteurized milk.
Tomorrow, I'll cover Reasons #1-5.
The State's Department of Health and Human Services warned yesterday that pregnant women should avoid consuming soft cheeses, processed meats (deli meats and hot dogs) and prepared salads. Listeria monocytogenes, which usually causes only a mild illness, can be deadly to pregnant women and their babies. So far, two pregnant women, all Latina, have miscarried after becoming infected with L. monocytogenes, and a fourth delivered prematurely. One additional miscarriage is being investigated to determine if it was also due to L. monocytogenes.
All of the illnesses occurred during a very short period of time, but different strains of L. monocytogenes were involved, suggesting that more than one type of food might have been contaminated. Alternatively, one food might possibly contain more than a single strain of L. monocytogenes - especially if that food is a cheese made from raw milk.
Tuesday, December 18, 2007
Campylobacter competes annually with Salmonella for 1st place honors in the CDC's list of most frequent causes of food-borne disease. The microbe is usually found in raw poultry, unpasteurized dairy products, and contaminated waters. Household pets can also be carriers of Campylobacter.
Symptoms of Campylobacter infection take 2-5 days to develop; they include diarrhea, fever and cramps, last from 2 to 10 days, and usually disappear without treatment. Occasionally (fewer than 1 in 1,000 cases), the infection leads to Guillain-Barré syndrome, a disease of the nervous system. Approximately 10% of victims of Guillain-Barré will die.
Campylobacter infection is only one of several possible consequences of drinking raw milk or eating cheese or other dairy products made from raw milk. Stay tuned for my version of Letterman's "top 10" – "Ten Reasons To Avoid Raw Milk".
This morning, USDA's Food Safety and Inspection Service announced yet another recall of raw ground beef due to contamination with E. coli O157:H7. The recall was a small one – only 102 pounds – but it illustrates clearly one of the problems with processors' attitudes. The contamination was not discovered by the Tennessee firm that processed the ground beef. It was detected by USDA after the meat had already been sold to consumers.
The U.S. consumer would have much more confidence in the safety of the country's meat supply if she could be sure that she and her family wasn't being used as the "canary in the cage" for the meat industry.
Monday, December 17, 2007
The list of foods includes a whole range of risky products - meats and vegetables - that are prone to botulism if not processed correctly. If you or anyone you know is a resident of the area and has purchased these products, please discard the products or return them to the store.
This type of behavior, in my opinion, falls under the category of "criminal negligence". Botulism is nothing to fool with.
Processors of “fresh-cut”, washed produce can economize by recycling water. The water is chlorinated, of course, to take care of those pathogens that might be lurking in the lettuce (or spinach). You know which ones - E. coli O157:H7 and Salmonella. After all, put enough chlorine in the wash water and the microbes will be killed. Most of them will, anyway.
The catch is that organic material - soil, bits of produce, fecal matter and whatever else is washed off the produce - inactivates the chlorine. And the more times the water is recycled through the produce washing processing line, the more organic material it collects and the less active chlorine is left to kill the microbes.
This isn’t rocket science - it’s simple arithmetic. Nor is it particularly new. A 1981 research paper described how turbid and organic-laden water reduced the ability of chlorine to kill bacteria. It's nice of USDA to go to the trouble of reconfirming that for us.
Packaged “fresh-cut, washed” produce is neither “fresh-cut” nor particularly well washed. Is it any wonder that spinach and lettuce have been associated with outbreak after outbreak of food borne disease for the last ten years and more?
Personally, I’m sticking with buying intact heads of lettuce and washing the individual lettuce leaves under running tap water just before making my salad.
Sunday, December 16, 2007
Not waiting to read the article, I immediately dove into the scientific literature to see what I had missed. Was it really possible for mad cow to be transmitted through milk? I couldn’t find a single research article to support this theory.
When I went back and read the original article, I discovered that the cattle hadn’t been fed milk, but rather a milk substitute that contained powdered animal fat. That didn’t make a lot more sense. Tallow (a rendered animal fat) has long been considered a low risk animal by-product by the World Health Organization.
The theory that Japanese cattle were infected with mad cow prions by being fed milk substitute containing Dutch animal fat is an old one. A very similar story appeared on CNN in 2001.
There are other possible explanations for the Japanese mad cow outbreak. The milk substitute was actually processed in Japan, using animal fat from the Netherlands as one ingredient. The powder might have been contaminated by meat and bone meal - a high-risk material for mad cow transmission - during mixing. Another source might have been dried cattle blood, which is sometimes used as an ingredient in mild substitute for feeding cattle.
There’s only one thing I’m sure of. Dutch milk did NOT transmit mad cow disease, in Japan or anywhere else.
Saturday, December 15, 2007
Following the detection of prohibited chemicals in previous shipments of seafood from China, the FDA placed a hold on the importation of five types of seafood from that country until the shipments cleared lab testing (at the importer's expense). But an exception was made in September for seafood from one Chinese processor, Zhanjiang Guolian Aquatic Products Corp. Now it would appear that the exempted processor is on the Canadian government's import alert list due to the presence of nitrofuran in a shipment of seafood. The nitrofuran-contaminated shipment of seafood, rejected by Canadian authorities in October 2007, had been routed through the U.S.
The Wall Street Journal quotes Guolian's general manager, Chen Han, as saying that the Canadian action was a "mistake", and was due to another company having falsely used Guolian's name. Mr. Chen claims that his company has emailed the Canadian government about this situation but, according to the Canadian Food Inspection Agency, no such email has been received.
Some questions have apparently been raised about the Guolian exemption. A former FDA employee, Benjamin England, suggested in the Wall Street Journal article that the Company's political connections with the Chinese government might have been a factor in the decision. Mr. Chen denies this, saying that the exemption is due to the Company's "good quality" operation.
The U.S. government has stated that Guolian's import "hold" exemption was part of a pilot project under the U.S.-China food safety agreement. Yet Guolian was added to the FDA's import detention list in April 2007, and then removed from that list just five months later - in September - three months before the announced food safety agreement between the U.S. and China. Something doesn't add up.
Friday, December 14, 2007
Cellulosic ethanol can be produced from a variety of plant material. At present, about 80% of it is made using corn. But the production process doesn't use up all of the corn. What is left behind after the fermentation and clean-up is a by-product known as "spent grain" or "distiller's grain".
Distiller's grain is not without its uses, especially to the cattle industry. Feedlot operators have been feeding this relatively inexpensive grain to their cattle. And distillers are enjoying the windfall revenue from what would otherwise be waste material. There is, however, a cloud on the horizon.
Recently, researchers at Kansas State University announced that feeding distiller's grain to cattle resulted in a higher incidence of E. coli O157:H7 in the hindgut of the animals. This contradicts findings reported by another major agricultural school, the University of Nebraska - Lincoln. Nebraska researchers did not find any indication that adding distiller's grain to the diet produced an increased incidence of E. coli O157:H7.
So there you have it - one of those situations that turns a microbiologist's hair gray. The USDA's Agricultural Research Service lab in Clay Center, NE is in the midst of a similar study, which is scheduled to be completed by the end of 2008. Best two out of three, anyone?
The process of raising cattle for slaughter has undergone many changes over the decades - in feedlot environment, types of feeds, and handling of manure and runoff. Unfortunately, thought is usually only given to the microbiological impact of these changes after the fact. For once, it would be nice to see data supporting the microbiological safety or benefits of a significant change before that change is implemented.
Purchasers of the affected production lots should discard the product or return it to the place of purchase.
Thursday, December 13, 2007
When melamine was first detected in pet foods that had been linked to animal deaths, veterinary toxicologists were puzzled. Melamine was never thought to be toxic to companion animals at the levels found in the contaminated products. The second contaminant, cyanuric acid, also was not known to be toxic at the levels at which it was found in the food. But the combination of the two chemicals proved deadly.
On May 1st, the University of Guelph reported that they had found the likely answer to the toxicity puzzle. Their preliminary report concluded:
Although still under investigation, it now appears that the combination of melamine and cyanuric acid has been linked to the unusual outbreak of acute renal failure in cats and dogs that have eaten the suspect products.The researchers reached this conclusion by adding both melamine and cyanuric acid to cat urine. The two chemicals, when both present in the urine, formed crystals that were identical to the crystals found in the urine of cats that had been sickened after eating the contaminated pet food. Neither melamine nor cyanuric acid alone produced these crystals.
The American Association of Veterinary Laboratory Diagnosticians commissioned Michigan State University to investigate fully the impact of the contaminated pet food and confirm the reason for its toxicity. University of Guelph and Colorado State University collaborated with MSU on the study. Their report has just been released, and the two main findings are:
- The contaminated pet food was probably responsible for the death of more than 300 cats and dogs
- The toxicity of the pet food likely resulted from the combination of melamine and cyanuric acid in the contaminated food.
Yesterday, Health and Human Services Secretary Leavitt announced that the U.S. and China had reached an agreement on food safety issues. The agreement provides for the eventual "embedding" of FDA inspectors in Chinese food processing facilities. But I don't expect this agreement to have a major impact. The FDA doesn't have nearly enough money in its budget - or trained personnel on its staff - to fulfill its domestic mandates.
Wednesday, December 12, 2007
L. monocytogenes is especially dangerous to persons who are immunocompromised, the very young, the elderly, and pregnant women. A pregnant woman who is infected with L. monocytogenes is at risk of miscarrying.
If you have purchased this cheese, please discard it or return it to the place of purchase. Do NOT, under any circumstances, eat cheese with this lot number. If you have discarded the packaging or cannot read the lot number on your package, please play it safe and discard the cheese.
"And remember, always make sure your cooked turkey is piping hot all the way through, with no pink meat, and all the juices run clear."Has the Irish Food Safety Promotion Board never heard of meat thermometers? In my post-Thanksgiving "Turkey P.S." posting of November 23rd, I reported that the internal temperature of the cavity stuffing was 10ºF lower than the temperature in the thickest part of the breast meat. A fully-cooked turkey is no guarantee of safe stuffing.
Please remember - always use a meat thermometer. Place it in the center of the stuffing and cook that turkey until the temperature of the meat thermometer reaches 165ºF (74ºC). This is the ONLY way to be sure that your Christmas turkey and its stuffing won't come back to haunt you after your Christmas dinner.
Tuesday, December 11, 2007
Cholera is caused by a bacterium, Vibrio cholerae, which is endemic (present all the time at low levels) in many areas of the world. The pathogen, which causes a severe, watery diarrhea resulting in life-threatening dehydration, is spread mostly through contaminated water. Crowded living conditions, poor sanitation and inadequate clean water supplies can also lead to secondary person-to-person transmission.
If the microbe is present in the environment, a cholera outbreak often flares up wherever a natural or man-made disaster strikes. Floods, earthquakes, war and tsunamis are all breeding grounds for cholera, which takes advantage of the crowded refugee camps, contaminated water and general chaos that follow in the wake of disaster to strike down its victims.
The list of countries that have struggled with cholera outbreaks in recent years include, among others, Angola, Afghanistan, Uganda, Sudan, Zambia, Liberia, Somalia and the Congo. It’s no coincidence that these same countries have been decimated by war, famine, floods or drought.
This year, it’s Iraq’s turn again. In September the WHO reported that nearly 300 cases of cholera had been confirmed in the area of Kirkuk, in northern Iraq. By the beginning of October, the number of cases in the north had surpassed 3,000, and the disease had spread to 9 of Iraq’s 18 provinces. Cases were reported in Diala, a province neighboring Baghdad, in Baghdad itself, and in a few other cities - including Basra.
Cholera is the great leveler. It doesn’t discriminate based on race, religion, gender, age or national origin. The tools to defeat it are well known - a clean, adequate water supply and basic sanitation. Isn’t it about time that Iraqi’s had reliable access to these fundamental items that most of us take for granted?
Monday, December 10, 2007
The researchers have determined that M. paratuberculosis produces a molecule that interferes with the ability of macrophages (a type of white blood cell) to kill E. coli. Macrophages play an important role in the immune system, swallowing up invaders and then killing them. Speculation is that this interference might produce inflammation in the intestines, leading to Crohn's.
If this work is corroborated, the researchers believe that it could lead to improved treatment for patients of Crohn's disease.
By the way, people who drink raw milk or who eat dairy products (such as yogurts or cheese) made from raw milk are at an increased risk of encountering Mycobacterium paratuberculosis.
Sunday, December 9, 2007
What caught my eye in these reports was the mention of the use of growth implants. These are pellets which are placed under the skin of the ear and slowly release growth hormones into the animal’s bloodstream. The hormones help the cattle “bulk up” more rapidly - just like athletes on anabolic steroids.
Growth promoting implants have been used by beef producers for more than 30 years. There are hundreds of articles in the scientific and technical literature touting the economic benefits of various growth-promoting hormones. I decided to check whether anyone had thought to investigate whether the use of these hormones might have an impact on the susceptibility of cattle to become colonized with E. coli O157:H7.
As far as I can tell, only one study has addressed this issue. A group of Canadian researchers systematically tested the effects of a growth promoting implant and the use of antibiotic feeding supplements on the presence or absence of E. coli O157 in cattle feces. In this study, some of the cattle (the control group) received neither hormones nor antibiotics; the others received a hormone implant, an antibiotic supplement, or both. At various times during the course of the 165-day experiment, feces from all of the cattle were tested for E. coli O157.
At no time during the entire study was E. coli O157 found in the feces of the “control” group - the cattle that received no hormones and no antibiotics. In contrast, more than half (54%) of the treated animals were positive for E. coli O157 at least once. The authors of the report (published in the Journal of Food Protection in November 2006) concluded that “...the high prevalence of E. coli O157 we observed may have been caused by the administration of growth-promoting agents...”
The authors went on to note that the differences between the treated and untreated cattle were not statistically significant. This was likely due, at least in part, to the small size of their experiment (only 80 animals in total). They went on to suggest that a larger study would allow more conclusive results to emerge. While we’re waiting, anyone for a hamburger?
Saturday, December 8, 2007
Infant botulism was first diagnosed in California nearly 30 years ago, and is thought to be one of the causes of Sudden Infant Death Syndrome. In the typical form of botulism, the microbe grows in a food and produces its toxin before the food is eaten. But infant botulism results when the victim ingests spores of Clostridium botulinum (or one or two other species of Clostridium). Those spores then germinate inside the intestines, and the toxin-producing bacteria multiply.
Symptoms of infant botulism include lethargy, constipation, and poor muscle tone. Infant botulism can be deadly if untreated. It is essential to have your infant seen by a doctor as soon as you suspect that something is wrong. Victims of infant botulism require an extended hospital stay - often in a pediatric intensive care unit and, usually, with mechanical breathing assistance for part of their stay. Intravenous treatment with Botulism Immune Globulin can speed up the recovery period. With appropriate care, the chances for a full recovery are good.
There is some controversy over the extent to which honey is the source of infant botulism. It is certainly not the only source of C. botulinum spores. The microbe is a normal inhabitant of soil and has been found in house dust and the contents of vacuum cleaner bags. But contaminated honey has been linked to some of the cases that have been reported in the United States, Japan and a handful of other countries, including Denmark.
An obvious question is whether certain types of honey (raw, pasteurized, organic, commercial) are safer than others. I have not found any evidence that this is so. The spores of C. botulinum are heat-resistant. They can easily survive pasteurization. And while C. botulinum will not multiply in the honey, its spores are very capable of surviving in a resting state until they reach a more welcoming environment, such as an infant’s large intestine.
The authors of the Pennsylvania State University study have suggested that honey is a better choice for relieving a child’s sore throat than commercial cough suppressant syrups. They have also - correctly - included a caution that honey should not be used for this purpose with children younger than one year. It’s far better for you and your infant to spend a few sleepless nights due to the infant’s sore throat than to risk exposing your baby to a potentially life-threatening illness.
Friday, December 7, 2007
Australia developed a risk-based approach to food import control that the FDA would do well to examine and learn from. Imported foods fall into one of three categories.
“Risk categorized foods” are those thought to present the greatest risk for food-borne disease. These foods are subjected to the most intensive scrutiny by Food Standards Australia. The first five shipments of each food on the high risk list from each foreign producer are inspected. After five consecutive shipments of a given food have passed muster, one in four shipments of that food from that producer are held for inspection. After 20 successful inspections, the frequency of inspection drops to one in 20 shipments. In all cases, shipments selected for inspection are held until results are known. Any unsatisfactory result causes the risk clock to reset and, of course, the unsatisfactory shipment is refused entry.
“Active surveillance foods” represent the next lower level of perceived risk. Ten percent of shipments of these foods from each and every supplying country are sampled for lab analysis. Because of the lower perceived risk, shipments of these foods are released after sampling.
“Random surveillance” covers all remaining foods not included in one of the two higher risk categories. Five percent of these shipments are sampled randomly for lab analysis.
Food Safety Australia reviews the results of these inspections periodically and, if appropriate, moves foods to a higher or lower risk category.
No system can ensure 100% safety, but basing a screening program on scientific risk assessment, and adjusting that assessment as more information become available seems a logical way to go.
Thursday, December 6, 2007
There are, as yet, no confirmed illnesses tied to the recalled water, but there is one illness complaint in Illinois that is being investigated. Please do NOT drink this water!
According to news media reports, the focus of the hearing was mainly on the issues surrounding risk assessment and the concentration of FDA attention on "high-risk" products. But in zeroing in on the "high-risk" issue, Senators have apparently overlooked an even greater flaw in this Plan - the so-called "mandatory recall" provision.
For several years, Senator Tom Harkin (now Chairman of the Senate Agriculture Committee) has sponsored legislation to provide the FDA and USDA with authority to mandate recalls of foods that present a hazard to human health. Each time, the Bush Administration claimed that it had no need of such authority; the voluntary recall system was working. Now, the Administration appears to have had a change of heart. Or has it?
The mandatory recall authority proposed in the Plan reads as follows:
"This authority would be limited to foods that the Secretary has reason to believe are adulterated and present a threat of serious adverse health consequences or death. It would be imposed only if a firm refuses or unduly delays conducting a voluntary recall. An order to recall food could only be issued by the HHS Secretary, Deputy Secretary, or Commissioner of Food and Drugs, and would be accompanied by appropriate due process rights."
There are several major flaws in this proposal. The most glaring is the total exclusion of mandatory recall authority for USDA, the federal government department that regulates all meat, poultry and processed egg products in the United States (including, for example, pepperoni-topped pizza). Another loophole is the lack of definition of the terms "threat of serious adverse health consequences", "unduly delays" and "due process rights". Are vomiting or diarrhea "serious adverse health consequences", or would the new authority only cover life-threatening situations such as botulism or hemolytic uremic syndrome (HUS)? How long is an undue delay? Who decides? And what constitutes "due process rights"? Will FDA need to go to court each time it needs to exercise its mandatory recall authority?
Canada has had mandatory recall authority on its books for ten years under the Canada Food Inspection Agency Act. The law, which covers all foods, simply states:
"19. (1) Where the Minister believes on reasonable grounds that a product regulated under an Act or provision that the Agency enforces or administers by virtue of section 11 poses a risk to public, animal or plant health, the Minister may, by notice served on any person selling, marketing or distributing the product, order that the product be recalled or sent to a place designated by the Minister.”
There is no requirement, under the Canadian law, for the Canada Food Inspection Agency to demonstrate that a company has "unduly delayed" implementing a recall. The authority is the Agency's to use as needed to ensure prompt action and to protect public health.
President Theodore Roosevelt once advised that we should "Walk softly and carry a big stick." That advice should be heeded by this Administration in its dealings with the food industry, both domestic and foreign. Unfortunately, the "mandatory recall" proposal described in the Food Protection Plan will have the FDA walking on eggshells with nothing more than a small twig in hand with which to enforce its mandate.
Wednesday, December 5, 2007
No illnesses have been reported so far.
"For example, we work cooperatively with U.S. Customs and Border Protection to help identify shipments containing potentially dangerous foods and prevent them from entering the country. By law, certain information must be submitted to FDA about food products before they are allowed to enter the U.S. We keep our Prior Notice Center open to receive this information 24 hours a day, 365 days a year. This means that FDA knows in advance when and where specific food shipments will enter the United States, what those shipments will contain, the countries and entities where they originate, and the facility where the food was manufactured.
So although we don't physically inspect every product, we electronically examine 100% of imported food products before they reach our borders. Based on criteria we have set up, an automated system alerts us to any concerns. Then we investigate further and, if warranted, do a physical examination of the product."
But compare this statement to the following excerpt from the recently released internal FDA report:
"Many of the FDA systems reside on technology that has been in service beyond the usual life cycle. Systems fail frequently, and even email systems are unstable — most recently during an E. coli food contamination investigation. More importantly, reports of product dangers are not rapidly compared and analyzed, inspectors’ reports are still hand written and slow to work their way through the compliance system, and the system for managing imported products cannot communicate with Customs and other government systems (and often miss significant product arrivals because the system cannot even distinguish, for example, between road salt and table salt)."FDA is overwhelmed and underfunded, and has been for many years. The problem gets worse day by day. Yet, instead of giving us an honest appraisal of the agency's problems, its spokespeople continue to paint a rosy picture of FDA's ability to carry out its diverse mandates. Is it any wonder that the agency is struggling to deal effectively with the deluge of imported products arriving at our ports of entry?
Tuesday, December 4, 2007
For many decades after gaining its independence, India suffered from hunger and poverty. More recently, the country has become a major international economic power, but its food and water infrastructure has failed to keep up with the rest of the country's progress.
An article in the November 2007 issue of Smithsonian makes very clear the difficulties that surround attempts to reduce pollution in the Ganges River. In spite of well-meaning efforts on the part of government and private individuals, the Ganges remains a repository for raw sewage, chemical pollutants and - until recently - rotting corpses.
The food safety situation in India is not much better. The FDA issues monthly reports on-line listing, by country, products that have been refused entry into the United States. Over the past 12 months, India and China have been neck-and-neck in the race for the title of "Most Often Refused Entry". FDA inspectors have turned back 1,836 shipments from mainland China and 1858 shipments from India during the past year. In October 2007, 22% of the refused shipments from both countries were rejected due to the presence either of "filth" or of a pathogen - most often Salmonella.
In the wake of this year's series of product safety scandals, China has taken steps to improve its safety regulation system. The government has issued new regulations on food safety and, most recently, the country announced a crack-down on manufacturers of "inferior" drugs and medical devices. Will it take a major international product safety incident to prompt India to do the same?
Monday, December 3, 2007
Salmonella enteritidis is the most common contaminant of intact shell eggs. Either there was a gross lapse of good sanitation practices in the bakery kitchen, or the cakes were decorated with an icing that contained raw egg.
Salmonella cannot grow in peanut butter, but it is shielded from heat damage by the high fat and low water content of this food. Peanut butter is so protective that the typical processing temperatures of 70-75ºC (158º-167ºF) can’t kill Salmonella in the product. Even boosting the temperature to 90ºC (194ºF) doesn’t do the job. For comparison, USDA recommends that we cook raw poultry to an internal temperature of 165ºF (74ºC), which is more than enough to kill Salmonella in that food.
This might help, by the way, to explain ConAgra’s problem. Salmonella probably found a home somewhere on the production line that wasn’t easily accessible for cleaning (maybe one of the filling nozzles?). The Salmonella probably was shed sporadically into the peanut butter. Even if the microbe entered the peanut butter before the pasteurization step or while the peanut butter was still hot, the Salmonella would have been protected from heat by the high fat/low water environment.
I was able to find just one study that compared the survival of Salmonella in different types of peanut butter at room temperature (21ºC) and in the refrigerator (5ºC). Under the conditions of that study, Salmonella survive for at least 24 weeks in peanut butter stored in the fridge - except in the case of natural peanut butter, in which most of the Salmonella died off during the 24-week period. Storage at room temperature hastened the death of Salmonella in all of the peanut butter varieties, although there were still a few survivors hanging around at 24 weeks.
What does this mean for storing an open jar of peanut butter? Room temperature storage might be a bit safer, and it's certainly easier to spread room temperature peanut butter than rock-hard peanut butter right out of the fridge. But neither storage temperature will ensure a safe product. For better or for worse, we have to rely on ConAgra and other peanut butter manufacturers for that.
Sunday, December 2, 2007
Out of curiosity, I "Googled" eggnog. This produced 162,000 hits. Limiting the search to "eggnog recipes" cut the list to 94,900. One of the first sites I looked at from this list was Martha Stewart's. To my dismay, her eggnog recipe uses raw eggs and makes absolutely no mention of the risk of Salmonella contamination. Given Martha Stewart's high profile, I wish she would have included a cautionary message or - even better - offered a recipe for eggnog that included a cooking step.
Sadly, Martha wasn't alone. The National Public Radio website's eggnog recipe was equally remiss, as were 80% of the sites that offered a recipe for home-made eggnog. Only 20% (19,100) of the sites offering eggnog recipes (I searched for "eggnog recipe cooked") provided a recipe for eggnog that included a cooking step. The American Egg Board was one site that offered a tasty-sounding recipe, but there were also many others to choose from.
According to USDA estimates, approximately 1 egg in 20,000 contains Salmonella enteritidis, a strain of Salmonella that has created a niche for itself in laying hens. Infected eggs appear completely normal; the shells have no apparent cracks or defects, and the yolk and white look completely normal. There is no reliable way to detect a contaminated egg. The proportion of eggs containing Salmonella varies from country to country, but the problem is widespread. For safety's sake, handle raw shell eggs in the kitchen just as carefully as raw poultry or other raw meats. And use pasteurized shell eggs in recipes such as Caesar salad, hollandaise dressings, and other dishes that do not include a cooking step.
So, enjoy your home-made eggnog this holiday season, but please make sure that Salmonella isn't one of the ingredients in the recipe.
Saturday, December 1, 2007
The findings reported by the Science Board are shocking, but not surprising to anyone who has followed the deteriorating state of our food safety systems these last several years. Among its series of observations, the Board had this to say about the current state of the FDA (and these are direct quotes):
- The FDA cannot fulfill its mission because its scientific base has eroded and its scientific organizational structure is weak.
- The FDA cannot fulfill its mission because its scientific workforce does not have sufficient capacity and capability.
- The FDA cannot fulfill its mission because its information technology (IT) infrastructure is inadequate.
- FDA does not have the capacity to ensure the safety of food for the nation.
The budget shortfalls and resultant lack of equipment, resources and personnel to carry out FDA's responsibilities have also seriously damaged the morale of agency personnel. This, in turn, has accelerated the loss of trained scientists and administrators - many of whom are difficult to replace.
While all parts of the agency are hurting, the two most seriously affected appear to be the Center for Food Safety and Nutrition (CFSAN), and the Center for Veterinary Medicine (CVM). The Board observes in its report that a simple lack of resources prevented the FDA from timely introduction and enforcement of new animal feed regulations to prevent the spread of mad cow disease in the United States. And even in the face of the recent pet food recalls, the CVM can only afford to have two people working on pet food issues.
The Food and Drug Administration once was one of the most respected agencies of the US government. In the 1970s, approximately 80% of Americans surveyed expressed confidence in the agency. That level of confidence has deteriorated (to 36% in 2006) along with the capabilities of the FDA to manage all of the statues that fall into its areas of responsibility.
Finally, the Science Board observes that "(r)ecommendations of excellent FDA reviews are seldom followed," and that failure to act on past recommendations "...has jeopardized the public's health." Let's hope that, this time, someone is listening.