Food Poisoning and Safety
- Infant botulism
- E. coli 0157: H7 food poisoning
- Campylobacter Food Poisoning
- What is "ptomaine food poisoning"?
- Food poisoning from the sea
- How is food poisoning treated?
- When should you see a physician because of food poisoning?
- How can food poisoning be prevented?
- How long can foods be stored?
- Is all moldy food dangerous?
- How can I keep food stored safely?
- How do I know if foods are cooked thoroughly and properly?
- Food safety frequently asked questions
The California Department of Health Services gets close to 27,000 reported cases of food poisoning each year. Because there are many more cases of food poisoning that are never reported, the actual number of food poisoning cases per year is unknown. The annual incidence of food poisoning nation wide is estimated to be as high as 80 million cases.
An estimated 55% of food poisoning cases are caused by improper cooking and storage of foods, and 24% by poor hygiene (not washing hands before handling food). Only 3% of cases are from an unsafe food source. Keeping your hands clean while working with food is the single most important thing you can do to prevent food poisoning.
About 20 organisms can cause food poisoning. After eating food contaminated with bacteria, the bacteria multiply in the stomach and the bowels. Some bacteria give off a toxin when they multiply. As a result, nausea, vomiting, abdominal cramps and diarrhea occur. Vomiting and diarrhea are the body's way of eliminating the toxin. Although the experience is unpleasant, most common cases of food poisoning run their course without needing medical attention.
Most cases of gastrointestinal symptoms (nausea, vomiting, abdominal cramps and diarrhea) are due to viral infections and are not true cases of food poisoning. Diagnosis of true food poisoning is difficult because the many organisms are found in different kinds of food and all have different incubation periods.
In California, three main bacteria are implicated in the majority of food poisoning cases caused by invasive bacteria: campylobacter, salmonella and shigella. Staph aureus is also a common cause of bacterial food poisoning. The dangerous E. coli 0157:H7, found in undercooked, contaminated ground beef and in contaminated fruits and vegetables, causes a very small number of cases. But because this strain of E. coli can cause kidney failure in children, each case is important.
Eating a substance and getting sick immediately afterwards is not the typical course for food poisoning. Most people are not aware that food eaten several days previously can be the cause of food poisoning.
Not all food poisoning organisms cause vomiting as a symptom but almost all organisms cause diarrhea. Blood in the stool is seen in several types of food poisoning and is considered a serious symptom. Abdominal cramps are common, even if vomiting is not present. Fever is infrequent but may be seen. Contact a physician if a fever or bloody stools are present.
BotulismWhat causes botulism?
Botulism is caused by the organism Clostridium botulinum, a spore-forming bacteria. Spores release a toxin that caused the illness. Although widely spread throughout our environment, botulism spores only become dangerous after producing a toxin in an oxygen-free environment of low acidity. Botulism food poisoning is very rare, but it can be life-threatening.
Botulism may result from eating improperly processed, low-acid foods such as green beans, mush-rooms, spinach, olives and beef or fish. Improper home canning methods account for many botulism cases. But, improperly processed commercial products can cause botulism too.
How can botulism be destroyed?
Spores are highly resistant to destruction. They can survive hours of boiling at 212½ F (100½ C). Pressure cooking at 240½ F (120½ C) for 30 minutes can kill spores. The toxin (not the spores) is readily destroyed by boiling at 212½ F (100½ C) for 10 minutes or heating to 176½ F (80½ C) for 30 minutes.
How do I avoid botulism risks?
Not even a taste: foods to avoid!
- Use only proper methods for canning low-acid foods. Follow directions for home canning exactly.
- Avoid commercially canned low-acid foods with leaky seals or deep dents in the seams of the can.
- Avoid all bent, bulging or broken cans.
- Discard any food that explodes from a can when it is being opened. If canned food contents spray across the kitchen or hit the ceiling when the can is being opened, it is potentially dangerous.
- Never, never taste a suspicious food product.
- Don't count on cooking to kill the botulism spores.
- When in doubt, throw it out. (Don't give it to pets either!)
Avoid tasting canned food that is soft, deteriorating, fermenting, or doesn't smell right. Even a taste is enough to cause illness. Throw the food away: It is not worth a life-threatening illness. Never taste suspicious foods for any reason.
What are the symptoms of botulism?
Botulism symptoms are not like those of ordinary food poisoning. Instead of stomach symptoms associated with other types of food poisoning, botulism causes toxic effects to the muscles and the nervous system.
Generally, victims experience symptoms 12-36 hours after eating, although symptoms have started as long as 96 hours after an exposure. The effects of botulism include blurred or double vision, dilated pupils, droopy eyelids that are difficult to open, dry, sore mouth and throat, a weak grip, and muscle weakness. Other symptoms can include difficulty swallowing and speaking, difficult breathing, major muscle weakness and paralysis.
Is there treatment for botulism?
Botulism can become life-threatening as the muscles used in breathing become paralyzed. Victims who expect the nausea, vomiting and diarrhea typical of ordinary food poisoning often wait too long to get medical help and consequently suffer a more severe illness. If you suspect botulism, get medical help as soon as possible. Antitoxin and good supportive care in a hospital setting have saved many lives.
Infant botulismInfant botulism is more common in the spring and the summer and is rare in the winter. Infants younger than one year of age, particularly between the ages of two to four months, are at highest risk. Symptoms include muscle weakness, a weak cry, a poor suck (difficulty in feeding), feeble crying, constipation, head lag, increased heart rate and a decreased gag reflex. A baby with infant botulism is described as a "floppy baby," as the baby will have weak muscles, especially in the arms, legs and neck.
Infant botulism has been associated with the ingestion of honey. The United States Center for Disease Control suggests that honey should not be given to infants under the age of 6 months. The Honey Industry Council extends that limit to one year of age to be extra safe. Honey is not an essential food for infants and should not be given.
E. coli 0157: H7 food poisoningWhat are the sources of this food poisoning?
E. coli 0157: H7 produces a powerful toxin that causes an estimated 25,000 cases of food poisoning each year in the United States. Most cases are associated with undercooked, contaminated ground beef. The organism lives in the intestines of healthy cows. Meat can become contaminated during slaughter when intestinal fecal matter is mixed with beef that is ground into hamburger. Contaminated meat looks and smells normal so it is not readily detectable. Bacteria on cow udders or milking machines can contaminate raw milk.
Unpasteurized apple juice and apple cider made from fallen apples contaminated with feces caused an outbreak of E. coli 0157: H7. Alfalfa sprouts, radish sprouts and lettuce have become contaminated when watered or grown in sewage-contaminated water. Swimming in or drinking sewage-contaminated water can also cause disease.
What symptoms does E. coli 0157: H7 cause?
The onset of symptoms occurs one to seven days after ingestion of a contaminated food. Typical symptoms include watery diarrhea and severe abdominal pain that can progress to bloody diarrhea. Little or no fever is seen.
A small portion (2%-7%) may go on to develop hemolytic uremic syndrome (HUS), where red blood cells are destroyed and kidney failure develops. This is particularly dangerous in children under the age of 5 years and in the elderly. HUS is treated with blood transfusions and kidney dialysis. Some patients who recover may need to be on long-term dialysis. The death rate is 3%-5%.
How do I prevent E. coli 0157: H7 food poisoning?
Cook all ground beef thoroughly. Make sure the meat is cooked throughout with no pink. Make sure all juices are clear, not pink or red. Make sure the inside of the meat is hot. If served an undercooked hamburger in a restaurant, send it back. Consume only pasteurized milk and milk products. Drink only water treated with chlorine or other disinfectants.
Campylobacter Food PoisoningWhat is campylobacter?
Campylobacter is the leading cause of bacterial food poisoning in the United States, causing 2 million to 8 million cases a year with 200-800 deaths. Eating undercooked chicken or food that has been in contact with raw chicken causes campylobacter. The Center for Disease Control estimates that up to 70%-90% of chickens are infected with campylobacter.
What are the symptoms?
Symptoms include abdominal cramps and pain, bloody diarrhea and fever. The symptoms last about a week. Researchers believe that campylobacter can cause a rare neurological disease called Guillain-Barre syndrome, which can cause paralysis.
How can I prevent campylobacter food poisoning?
To prevent the disease, make sure all chicken is thoroughly cooked with no pink remaining. Wash your hands frequently while working with raw chicken. Use paper towels to dry your hands. If you are using a sponge or dish-cloth to clean the counters, use a fresh one after working with raw chicken. Wash your cutting board with a diluted bleach solution before using again. Any utensils or dishes that had contact with raw chicken need to be washed well with soap and water before using again.
What is "ptomaine food poisoning"?The dictionary defines ptomaine poisoning as "food poisoning caused by bacteria or bacterial products." Ptomaine poisoning is not a special kind of food poisoning and it is not a deadlier type of food poisoning. Ptomaine is an old-fashioned general term for any type of food poisoning caused by bacteria. The term "ptomaine food poisoning" is not used medically anymore.
Food poisoning from the seaPoisoning from eating toxic fish is very uncommon. If you become ill after eating fish, call the Poison Center for more information.
How is food poisoning treated?Do not induce vomiting, as it will NOT prevent food poisoning. Bacteria and other microscopic organisms cause food poisoning. There is no way that vomiting will remove every bad organism in the stomach. Food poisoning can still occur even if vomiting was induced. Unfortunately, there is no way to prevent food poisoning once bad food has been eaten. That is why prevention is the key.
Vomiting and diarrhea are how the body rids itself of tainted food. The best treatment is to let food poisoning run its course. In most cases, once the body is emptied of the bad food, the food poisoning is over.
It is essential to prevent dehydration (loss of body fluids). Replace lost fluids with small but frequent sips of liquids, such as Gatorade®, 7UP®, apple juice, broth, bouillon or Pedialyte®. Report all cases of restaurant food poisoning to your county public health department.
When should you see a physician because of food poisoning?Young children, elderly people and people with severe medical conditions are at a highest risk of dehydration due to food poisoning. Contact your physician if there is:
If botulism, infant or adult, is suspected, immediately contact a physician. If unusual symptoms occur after eating fish, contact a physician.
- Diarrhea lasting longer than 24 hours
- Vomiting lasting longer than 12 hours
- Blood in the stool
- Vomiting and diarrhea that are so intense that severe muscle cramping occurs
- An inability to keep down any liquids at all for 12 hours.
How can food poisoning be prevented?Following these rules can prevent most food poisoning cases:
Contaminated food may or may not smell, taste or look bad. Don't taste suspicious foods. Don't ask anyone else to taste it either.
- Wash your hands! Wash them before, during and after food preparation. Use soap and warm water and wash for 20 seconds. Wash after touching raw meat, fish or poultry. Wash your hands after every trip to the bathroom. Washing is the most important thing you can do to prevent food poisoning.
- Use hot, soapy water to wash cutting boards, utensils and anything else that was used to prepare food.
- Use a diluted bleach solution to clean cutting boards and countertops after food preparation.
To clean kitchen sponges and dishcloths, rinse them in water, squeeze out the excess water and microwave at full power for 60 seconds. Be careful in removing hot items from microwave so you don't burn yourself.
- After handling raw meat, fish or poultry, do not reuse the same utensil or plate. Bacteria from the raw juices will contaminate other food.
- Do not use a sponge or dishcloth to clean surfaces that have touched raw meat, fish or poultry. Use soap, water and a disposable paper towel.
- Wash all fruits and vegetables well before eating.
- Cook all food thoroughly.
- Taste food only when it is thoroughly cooked. Use a clean spoon each time.
- Keep hot foods hot and cold foods cold. If food is allowed to remain at room temperature for two hours or longer, bacteria can multiply and cause food poisoning.
- Refrigerate all leftovers soon after meals.
- Hot food does not have to be cooled before placing it in the refrigerator.
- After shopping, refrigerate frozen food as soon as possible. If thawed, use immediately. Do not refreeze.
- Defrost meats and poultry in the refrigerator or the microwave.
- When camping, don't drink stream water. No matter how clear the water looks, it can still contain dangerous bacteria and other organisms.
- Don't buy or use food from dented, bulging or rusted cans. If you have a can with a dent on the seam, throw it away. Don't even open it.
Even a tiny amount of contaminated food can cause severe illness. If you have any doubt about the safety of the food, throw it out! Don't give possibly spoiled food to pets: They can get sick from bad food, too. Not even the most expensive food is worth a case of food poisoning, human or animal. Dispose of potentially tainted food by placing it down the garbage disposal or wrapping tightly and placing in the trash.
How long can foods be stored?
Many people do keep their food longer than the above guidelines. If you keep your food longer, make sure you check it each time to see that it has not turned moldy, slimy, stinky, rancid or otherwise rotten. Always check the food BEFORE you taste it.
- Refrigerated steaks and roasts should be used within three to four days after purchase.
- Ground meats, fresh poultry and raw fish should be used within one to two days after purchase.
- Milk, cream, cottage cheese and cream cheese are good for a week after opening.
- Hard cheeses that are tightly wrapped are good for two to three months.
- Eggs are good for three to four weeks. Keep them refrigerated.
- Cooked or uncooked vegetables are good in the refrigerator for three to five days.
- Berries are only good for about three to five days in the refrigerator before they mold or rot.
- Bread, cake and cookies (or anything made from a batter with yeast or wheat) should be used within a week to avoid mold.
- Baked goods will last longer (two weeks) if refrigerated.
- Deli meats should be used within four days after opening the package.
- Leftover meats are good for three to five days.
- Leftover chicken, gravy, sauce, chicken or tuna salads and turkey pies are only good for one to two days.
- Mustard, soy sauce, Worcestershire sauce and other condiments should be used within a year of opening the container.
- Mayonnaise, once opened, is good for two months.
- Open bottles of salad dressing are good for three months.
- Ketchup, jams, jelly and peanut butter are good for six months.
- Opened jars of salsa should be discarded after a month.
- Frozen food is good for a year if tightly wrapped and stored consistently at 0½ F.
- If you cannot remember when a food was placed in the refrigerator, throw it out.
Is all moldy food dangerous?Food poisoning is caused by various bacterial organisms. Mold is not a bacteria and will not cause food poisoning. Mold does not cause botulism unless the product was already contaminated with the botulism organism.
Mold can cause illness, especially if the person is allergic to molds. Usually though, the main symptoms from eating moldy food will be nausea or vomiting from the bad taste and smell of the moldy food.
How can I keep food stored safely?
- Keep refrigerator temperature between 35-40½ F and freezer temperatures at 0½ F or lower.
- Space food items in your refrigerator and freezer so cold air can freely circulate.
- Wrap raw meat, fish or poultry in separate plastic bags. Place them on a plate or tray on the lowest shelf in the refrigerator to keep leaking juices from dripping on other foods.
- Freeze fresh meat, fish or poultry if they are not going to be used in the next couple days. Rewrap meat packages in aluminum foil or freezer paper to keep the meat airtight.
- Pack perishable foods in coolers with ice or ice packs when cleaning or defrosting your refrigerator or freezer.
- Use plenty of ice in the picnic chest to keep foods such as egg salad, potato salad, macaroni salad or any dishes made with mayonnaise or cream cold. Don't leave these foods in the sun.
- After holiday meals, remember to place the leftover turkey in the refrigerator. Do not leave the turkey on the counter or in the oven overnight.
- Do not leave stuffing in the turkey when you refrigerate it.
How do I know if foods are cooked thoroughly and properly?
- Red meat should be cooked to 160½ F.
- Large cuts of red meat can be cooked to medium rare, 145½ F.
- Ground meat and hamburgers should be cooked all the way through until the center is at least 160-165½ F.
- Cook fish to 130-140½ F, until the center looks opaque when tested with a fork.
- Cook pork to 155½ F with no pink.
- Cook chicken to 170-180½ F or until the juices run clear.
- Eggs should be cooked until both the yolk and the white are firm.
- Heat left-overs to 165½ F.
- When reheating sauces, soups and gravies, bring them to a boil.
- Never drink unpasteurized milk or dairy products.
- Do not eat raw cookie dough that contains eggs.
- Do not use leftover marinades as they contain raw meat juices.
Food safety frequently asked questionsIs it safe to store food wrapped in aluminum foil?
Acidic foods, such as dishes with tomato sauce, wrapped in aluminum foil and stored in the refrigerator can "eat" or "corrode" little holes in the foil wrap. This is a reaction of the food acids with the foil but it is not dangerous. The food may have a slight metallic taste but it has not turned poisonous. If the food tastes metallic, you may wish to discard it because many find the taste unpleasant. If the food tastes normal, it is safe to eat.
What is detinning?
Many people are surprised, after opening tomato sauce or other acidic foods, to discover dark discolor-ations on the can lining or can lid. Acid in these foods interacts with the tin can lining to cause these spots. This process is called "detinning" and is not dangerous. The foods can still be used.
What if there are worms/weevils in the food?
Many people have had the unpleasant surprise of finding live creatures wiggling in their food. Food or candy containing peanuts is commonly found to contain worms. Oatmeal, cereals and other grain products frequently have little weevils. People who have already tasted the food and then find the live creatures tend to vomit immediately. While the idea is disgusting, there is no danger. The bugs and worms are destroyed by the stomach acids and will not turn into parasites.
Actually, insects are full of protein and are low-calorie. They are considered survival food by the military. If you were stranded in the wilderness without food, you could eat bugs, grubs, worms and other insects to prevent starvation. Most people who have accidentally eaten a bug do not find that particularly reassuring. No real treatment is needed. Inducing vomiting is not necessary.
Are fish worms dangerous?
Fish that live close to the shore are most likely to have parasites. These include flounder, rockfish, salmon and sole. Light cooking is sufficient to kill the parasites and bacteria that are found in fish. These flat fish should not be eaten raw.
What does it mean if the fish smells?
Fish that is not fresh can smell and taste like ammonia. The fish is NOT dangerous but will not taste pleasant. When you buy fish or seafood, look for no smell or a very mild fish smell. A strong smell indicates fish that is not fresh.
Can food be safely stored in metal containers?
Leaving fruit juices, tuna fish or other canned fruits and vegetables in the original metal can is not recommended. Acidic foods can interact with the metal, imparting a metallic taste to the food. To avoid this unpleasant experience, transfer leftover foods or juices to sealable glass or plastic containers. If a product stored in a can is accidentally tasted or eaten, the food may taste bad but it will not be dangerous.
What happens if the freon leaks in the refrigerator/freezer?
When the freon line leaks or bursts, the food in the refrigerator or freezer becomes contaminated with freon. The food may not taste as good, if it was not well wrapped, but will not be dangerous to eat. The food does not have to be thrown away, unless it becomes warm due to refrigerator failure. Freon is mainly dangerous when large amounts are inhaled in a small, enclosed area.
What do the various dates on food mean?
"Expiration" or "Exp" is the last date on which a product should be used. If the date has passed, throw it away.
"Sell by" indicates the last day on which the product should be sold. You can keep the food two to three days longer than that if it is well-refrigerated.
"Best if used by" is the date by which the manufacturer guarantees the freshness and quality of the food. It is not dangerous to use the food after that date, but the food may not have top quality or top nutritional value after that date.
"Packed on" dates are sometimes found on canned and frozen food. This is not useful information unless you know when the food was picked and processed before the freezing or canning. As a rule of thumb, frozen foods can be kept for three to four months after that date. Canned goods can be stored for up to a year beyond that date. Foods stored and kept longer may lose their flavor and nutritional value. But they are not dangerous.
Products may not necessarily be unusable after the date on the package. Examine the food carefully before using. To be safe, use common sense: If the food looks or smells unusual, don't use it.
If you leave a spoon in the mayonnaise jar, does it turn the mayonnaise bad?
The metal of the spoon does not react with the mayonnaise and form a poisonous substance. The problem with leaving a spoon in the foods like mayonnaise depends on the cleanliness of the spoon. If the spoon was used with other food or used for eating, the spoon is considered to be dirty as it harbors bacteria. Placing the dirty spoon in the mayonnaise places all that bacteria in the mayonnaise as well. Food poisoning can develop from the bacteria growing in the mayonnaise. That is why only clean utensils should be used in food.
Is it true that shrimp can glow in the dark?
If shrimp eat large amounts of luminescent organisms, they can glow in the dark. Although it can be surprising and alarming to see the remains of your dinner glowing in the dark in the night, it is not radioactive and it is not dangerous.
How long can food be left out before it is dangerous?
Food left out at room temperature for two hours or longer is at risk for causing food poisoning.
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Disclaimer: This web site is designed to be informational and educational. Under no circumstance is this web site meant to replace the expert advice of a qualified poison specialist or physician. In the event of a poison emergency, call the nearest poison center immediately -dial, 1-800-222-1222 or contact 9-1-1 emergency services if the person who is poisoned cannot wake up, has a hard time breathing, or has convulsions.