Food and Water Safety - Nutrition

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High-Risk Populations

A number of factors influence whether an individual becomes ill after consuming a food or beverage that has been contaminated with a pathogen or toxin. The number of pathogenic microbes in a food or the amount of toxin it contains can contribute to the risk and severity of a food-borne illness. Furthermore, individuals vary in their vulnerability to many food-borne pathogens, mainly due to differences in how their immune systems respond. In general, high-risk groups are pregnant women, very young children, older adults, and persons who suffer from serious chronic illnesses or weakened immune systems. Very young children typically have underdeveloped immune systems, increasing their susceptibility, whereas older adults can have decreased immune responses due to the aging process. In addition, older adults may produce less gastric acid, which can reduce their ability to kill any bacteria consumed in foods.

Toxins

As mentioned earlier, toxins are poisonous substances that can be produced naturally in foods by living organisms. Some pathogenic bacteria cause food intoxication by releasing toxins.

Causes of Food-Borne Illness

Bacteria, viruses, parasitic worms, and even chemicals can result in food-borne illness. Many kinds of food-borne pathogens infect the digestive tract, inflaming the tissues and causing an "upset stomach" within a few hours after being ingested. A few types of food-borne pathogens multiply in the human intestinal tract, enter the bloodstream, and cause general illness when they invade other tissues. These are examples of food-borne illnesses related to infection from the pathogen. Other pathogens do not sicken humans directly. Instead, these organisms contaminate food and secrete toxins. Toxins are poisonous substances. In many instances, toxins cannot be visually detected or identified through tasting or smelling of the food, nor can toxins be destroyed through usual cooking or freezing methods. When the contaminated food is eaten, the toxins irritate the intestinal tract and cause a type of food-borne illness called food intoxication (or food poisoning). In some cases, food intoxication can lead to death.

Preventing Food-Borne Illnesses: Food Selection

Food selection guidelines emphasize selecting unexpired foods, purchasing fresh produce, and keeping cold or frozen foods at the proper temperature during transport home. To reduce the risk of food-borne illness: Packaged and fresh perishable foods -Check "best by" dates on packaged perishable foods. -Choose meats and other animal products with the latest dates. -Do not buy food in damaged containers; for example, avoid cans that leak, bulge, or are severely dented, or jars that are cracked or have loose or bulging lids. Dairy and eggs -Open egg cartons and examine eggs; do not buy cartons that have cracked eggs. -Purchase only pasteurized milk and cheese, as well as fruit and vegetable juices (check the label). -Store whole eggs in their cartons, even if the refrigerator has a place for storing eggs. Egg cartons are designed to keep eggs fresh longer than a refrigerator's egg compartment. Meats, fish, and frozen foods -When shopping, select frozen and cold foods last, especially potentially hazardous foods such as meats, poultry, dairy, or fish. Pack meat, fish, and poultry in separate plastic bags, so their drippings do not contaminate each other and other groceries. -After shopping for food, take groceries home immediately. -Refrigerate or freeze meat, fish, egg, and dairy products promptly.

Pathogens in Food

For thousands of years, people have used certain microbes to produce a variety of foods, including hard cheeses, yogurt, leavened breads, pickled foods, and alcoholic beverages. These foods are generally termed cultured foods. When microorganisms metabolize nutrients in food, they often secrete substances that alter the color, texture, taste, and other characteristics of the food in beneficial and desirable ways.

Ground Meats, Poultry, and Cooked Fish

Ground meats, poultry, and fish are highly perishable and must be thoroughly cooked to avoid being a source of food-borne illness. The interior portion of an intact piece of raw animal flesh is normally free of bacteria because the tissues are not exposed to air. However, ground meats, fish, and poultry products are often contaminated with microbes. Prior to being ground up, the surface of a chunk of meat, fish, or poultry may contain relatively harmless concentrations of pathogens. The grinding process, however, mixes the pathogens throughout the meat. At the same time, grinding the meat greatly increases its surface area, exposing more of the protein-rich tissues to microbes in air. Furthermore, the meat grinder can be a source of pathogens and spread them to the food product, especially if the machine was not properly cleaned after its last use. The particles of food that remained in the grinder can provide food for pathogenic microorganisms. Therefore, surfaces that touch ground meats should be cleaned carefully.

Hand Sanitizer

If washing your hands with soap and very warm water is not an option, hand sanitizers are a good alternative. According to the CDC, effective alcohol-based sanitizers should contain at least 60% alcohol. Although sanitizers can quickly reduce the number of microorganisms on hands, they do not eliminate all pathogens. They are also not as effective when hands are visibly dirty.

Nonchemical Methods of Pest Management

Integrated pest management (IPM) involves using a variety of methods for controlling pests while limiting damage to the environment. IPM methods include growing pest-resistant crops, using predatory wasps to control crop-destroying insects, and trapping adult insect pests before they can reproduce. It is important to note that IPM permits the use of chemical pesticides but only as needed to enhance the effects of nonchemical methods. Studies suggest that IPM techniques generally increase crop yields and economic profits, while reducing the use of chemical pesticides.31 As IPM programs become more widely adopted, conventional farmers will depend less on the use of chemical pesticides. Fruits and vegetables grown without use of pesticides are available and may bear an "organic" label. These products generally are more expensive than those grown using pesticides, and they are not necessarily safer or more nutritious than conventionally produced foods. However, organic products are generally more "environmentally friendly" than conventional produced foods.

Intentional and Unintentional Food Additives

Many intentional food additives help maintain the safety of foods by limiting the growth of bacteria that cause food-borne illness. Other additives protect against the action of enzymes that can lead to undesirable changes in the food's color and taste. These unwanted chemical changes occur when enzymes that are naturally present in certain foods are exposed to the oxygen in air. Antioxidant additives, including vitamins E and C and a variety of sulfites, can prevent oxygen from reacting with these enzymes. Color additives include dyes, pigments, or other substances that provide color to foods, drugs, or cosmetics, such as beta-carotene in margarine and FD&C (Food, Drug, & Cosmetic) Red No. 40 in cherry-flavored cough syrup.

Differences Between Food-Borne Illness and "Stomach Flu"

Many people mistakenly report that they have the "stomach flu" when in reality they are suffering from a food- or water-borne illness. "Flu," or influenza, is an infectious disease caused by specific viruses that invade the respiratory tract. Influenza is characterized by coughing, fever, weakness, and body aches. In contrast, food-borne illness primarily affects the digestive system and not the respiratory system. Intestinal cramps, diarrhea, and vomiting are not typical signs and symptoms of influenza, especially in adults. Coughing is not a usual sign of a food-borne illness. Thus, it is inaccurate to call a bout of diarrhea and intestinal cramps the "stomach flu."

Accidental Food Contaminants

Many substances can accidentally enter food during processing. These accidental food additives include common biological and physical food contaminants such as insect parts, rodent feces or urine, dust and dirt, and bits of metal or glass from machinery used to process food. Although some of these substances may not be harmful to health, most people find it unappealing to have such unintentional ingredients in their foods. Chemical contaminants also enter foods unintentionally. Toxic metals, such as lead, cadmium, and mercury, are naturally in our environment, and these elements may also be in our food. Poisonous human-made compounds such as benzene and polychlorinated biphenols (PCBs) are in the environment as well. Toxic metals or poisonous compounds resulting from manufacturing practices can pollute sources of water used by consumers (well water, for example). Water from municipal supplies is analyzed regularly to determine its concentrations of toxic substances, and therefore, drinking water from municipal sources is generally safe. However, people who rely on privately owned wells should have the water tested routinely.

Microwave Cooking

Microwave cooking can result in uneven heating that does not destroy microbes in the cool spots. While cooking a food in a microwave oven, keep the dish covered, and stop the oven occasionally to stir the food. Stirring the food reduces uneven heating. Cook the food until it reaches 165°F. Microwave cooking is not recommended for stuffed foods because during cooking, the temperature of the stuffing may not be high enough to kill pathogens.

Comparing Bottled and Tap Water

Millions of Americans have been turning away from the tap and choosing to drink bottled water instead. According to the Beverage Market Corporation and International Bottled Water Association, each American consumed 34 gallons of bottled water in 2014. That amount of bottled water is over 50% more than the amount consumed in 2000. The U.S. population drinks more bottled water than milk, juice, or any other beverage, except carbonated soft drinks. Safety standards for bottled water are similar to those established by the EPA for tap water. According to FDA guidelines, bottled water manufacturers are responsible for producing safe products.

Maintaining Proper Temperature of Foods

Most microbes grow well when the temperature of a potentially hazardous food is between 40°F and 140°F—the "danger zone". Cooking foods to the proper temperature destroys food-borne pathogens, such as norovirus and E. coli O157:H7. To be safe, a product must be cooked to an internal temperature that is high enough to destroy harmful pathogens and certain bacterial toxins. Using a meat thermometer is a reliable way to ensure that meat, poultry, thick pieces of fish, and egg-containing dishes have reached the proper internal temperature without overcooking.

Contaminated Food or Beverage

No longer wholesome, that is, pure or safe for human consumption. Contamination occurs when something enters food or beverages unintentionally. Such contaminants include pathogens, insect parts, residues of compounds used to kill insects that destroy food crops, and metal fragments from food-processing equipment. Contaminants may or may not be harmful, but pathogens are always harmful.

Food-Borne Illness

Signs and symptoms of food-borne (and water-borne) illnesses generally involve the digestive tract and include nausea, vomiting, diarrhea, and intestinal cramps. Most pathogens have an incubation period, a length of time in which they grow and multiply in food or the digestive tract before they can cause illness. Incubation periods can range from 1 hour to several days. Thus, if a person develops signs and symptoms of a food-borne illness, he or she might have difficulty identifying the source of the illness.

Organizations that regulates food in the U.S.

The Food and Drug Administration (FDA) of the U.S. Department of Health and Human Services and the U.S. Department of Agriculture (USDA) are the key federal agencies that protect consumers by regulating the country's food industry.

To reduce your exposure to BPA, consider taking these actions:

-Avoid heating foods in polycarbonate plastic containers. -Avoid plastic containers that have the symbol. -Do not wash polycarbonate containers in the dishwasher or with harsh detergents. -Reduce your intake of canned foods. -Cook or store foods and beverages in glass, porcelain, or stainless steel containers. -Avoid serving foods (especially hot foods or liquids) on or in polycarbonate dishware, cups, or eating utensils. -Avoid using older baby bottles and plastic chew toys that may have been made with BPA.

Percentage of people experiencing food-borne illness

48 million Americans become sick from food-borne illnesses, and of those persons who contract such ailments, 128,000 require hospitalization and over 3000 die. However, the United States has one of the safest food and water supplies in the world, primarily the result of cooperating federal, state, and local agencies that regulate and monitor the production and distribution of food and sanitation of water.

Raw Fish

Eating raw fish, such as in sushi, can be safe for most healthy people if the fish is very fresh before being commercially frozen and then thawed. While frozen, the fish must maintain an internal temperature of −4°F or less for at least 7 days. he freezing step is important because very cold temperatures can kill pathogenic worms that are often in fish tissues. If a person chooses to eat uncooked fish, it should be purchased from reputable establishments that have high standards for quality and sanitation. Nevertheless, it is a good idea to avoid eating any raw animal products, including fish.

Heating Food

Failing to cook foods properly can also increase the likelihood of food-borne illness. Pasteurization is a special heating process used by many commercial food producers to kill pathogens. In the United States, for example, most juices and milk have been pasteurized before they are marketed. The nutrient composition of pasteurized foods may be slightly lower than that of unpasteurized foods, but the benefits of pasteurization far outweigh the loss of nutrients.

Food Handling

Improper food handling frequently results in food-borne illness. A common mistake is failing to wash cutting boards and food preparation utensils after they come in contact with raw meat or poultry and then using the contaminated boards and utensils to prepare other foods, such as raw carrots for a salad. Pathogens from the raw meat or poultry can be transferred to the carrots and could produce food-borne illness. This transfer of pathogens is called cross-contamination.

Food-borne illnesses

Occur when microscopic agents (microbes) or their toxic by-products enter food or water and then are consumed.

Vermin

One common route for transmitting harmful microbes involves vermin, animals that often live around sewage or garbage, such as flies, cockroaches, mice, and rats. When vermin land on or crawl across filth, they pick up pathogens on their feet. Then, if the vermin comes in contact with food, they can transfer the pathogens to humans. To reduce the risk of food-borne illness, keep flies, cockroaches, and other vermin away from food.

Prions

Prions are similar to viruses in that they are not living organisms but rather infectious proteins that are folded improperly. Unlike typical food-borne pathogens that cause nausea, vomiting, and other gastrointestinal disorders, prions are responsible for neurodegenerative diseases (diseases that damage cells of the brain and spinal cord). Neurodegenerative diseases can occur in both animals and humans. The disease spreads when the abnormal, infectious proteins cause normal proteins to fold incorrectly. The most notable prion disease is bovine spongiform encephalopathy (BSE), otherwise known as "mad cow disease." When people consume certain tissues from infected cows, the humans may develop variant Creutzfeldt-Jakob disease (vCJD). Fortunately, BSE is very rare in the United States due to strict food-safety regulations.

Pregnant Women and Listeria monocytogenes

The bacterial species Listeria monocytogenes is a pathogen that can be present in milk and milk products that have not undergone proper pasteurization. The food-borne illness that results from ingesting Listeria monocytogenes is called listeriosis. Foods typically associated with listeriosis include raw milk; soft cheeses made from raw milk; raw, undercooked, and smoked seafood; and ready-to-eat processed meats, such as hot dogs, luncheon meats, or deli meats. A pregnant woman is 10 times more likely to contract listeriosis than the general population. According to CDC, about 1600 people get sick from Listeria each year, and approximately 260 die from the infection. Listeria bacteria can be passed from mother to her unborn offspring through the placenta and result in miscarriages, premature delivery, or serious health problems for the newborn. Signs include fever and other nonspecific symptoms such as fatigue and aches. Because the bacterium is not destroyed by salt and other food preservatives, pregnant women should avoid eating foods that are not heated adequately.

Common Food-Borne Pathogens

The major kinds of food-borne pathogens are bacteria, viruses, and protozoa. Less common pathogens include toxins, produced by fungi or in seafood; parasitic worms; and prions. In the United States, bacteria and viruses are responsible for most cases of food-borne illness.

Key Federal Food Safety Agencies

To help protect the U.S. food supply, the FDA's Center for Food Safety and Applied Nutrition performs many important tasks, such as regulating nearly all domestic and imported food sold in interstate commerce and enforcing federal food safety laws. Additionally, the FDA establishes standards for safe food manufacturing practices, such as Hazard Analysis and Critical Control Point (HACCP) programs. HACCP is a science-based, systematic approach to preventing food-borne illness by predicting which hazards are most likely to occur in a food production facility. Although the FDA oversees the safety of most foods, the USDA's Food Safety and Inspection Service (FSIS) enforces food safety laws for domestic and imported meat and poultry products. FSIS staff inspect beef, poultry, and other food animals for diseases before and after slaughter, and the agency ensures that meat and poultry processing plants meet federal standards.

Keep hot foods hot and cold foods cold

To reduce the risk of food-borne illness: -Always thaw high-risk foods in the refrigerator, under cold running water, or in a microwave oven. -Cook foods immediately after thawing. -Marinate food in the refrigerator, and if marinating meat, fish, or poultry, discard the marinade. -Do not remove cold foods from the refrigerator or hot foods from the stove or oven until it is time to serve them.

Food Preparation: Canned Foods and Fresh Produce

To reduce the risk of food-borne illness: -Do not use foods from containers that have damaged safety seals because the food they contain may have been contaminated. -Do not taste or use food that spurts liquid or has a bad odor when the can or jar is opened. -Before preparing fresh produce, carefully wash the foods under running water to remove dirt and bacteria clinging to the surface. -Avoid eating moldy foods. Small amounts of mold on hard cheeses and on firm fruits and vegetables can be removed by cutting away the mold along with at least 1 inch of food that surrounds the moldy area. If mold is too extensive, discard the entire food. -When in doubt, throw the food out.

How to sanitize a sponge

To sanitize a kitchen sponge, wash it in the dishwasher with the drying cycle on or place a wet sponge in a microwave and heat for 60 seconds

Potentially Hazardous Foods

To survive and multiply, most microbes need warmth, moisture, and a source of nutrients, and some also require oxygen. In general, potentially hazardous foods are warm and moist, contain some protein, and have a neutral or slightly acidic pH. Many of the foods Americans eat every day, such as meats, eggs, milk, and even some produce, fit this description.

Viruses

Viruses are another common source of food-borne infection. A virus is simply a piece of genetic material coated with protein. Viruses must invade a living cell to produce more viruses. Unlike certain bacteria, viruses do not secrete toxins, and therefore, they do not cause food intoxication. Contaminated food or water, however, can transmit viruses to humans and cause food infection. The most common virus-contaminated foods include shellfish, salads, and ready-to-eat foods.

Acrylamide

Acrylamide is a naturally occurring compound in foods that was not discovered until 2002. The compound forms when foods containing sugars and the amino acid asparagine are heated to high temperatures, such as when foods are roasted, fried, or baked. Acrylamide tends to form mostly in plant-based foods, especially grains, potatoes and products made with potatoes, and coffee beans. The FDA has been actively researching the safety of acrylamide; in March 2016, the FDA released guidance to the food industry on how to limit acrylamide in processed foods. Consumers can avoid producing acrylamide during cooking by boiling, steaming, and microwaving potatoes and grains. Sources of acrylamide include overly browned potato- and grain-based foods, so it is wise to avoid eating burnt bread or French fries.

Proper storage to prevent cross-contamination

Cross-contamination is a threat not only during food preparation but also during food storage. Therefore, keep all foods, including leftovers, covered while they are in the refrigerator. This practice can prevent drippings from foods that are often contaminated, such as raw chicken, from tainting other foods. Furthermore, store raw meats, fish, poultry, and shellfish on lower shelves of the refrigerator, so they are separated from foods that are to be eaten raw. Clean: Wash hands and surfaces often. Separate: Do not cross-contaminate. Cook: Cook to proper temperatures. Chill: Refrigerate promptly.

Safeguarding the food an water supply

The EPA, FTC, and CDC are other team members of the federal government that provide support to the FDA and USDA in safeguarding the food and water supply. The EPA oversees the quality of our drinking water by establishing safe drinking water standards and assisting state officials in their efforts to monitor water quality. Furthermore, EPA staff regulate toxic substances and wastes to prevent their entry into foods and the environment. In an effort to prevent consumer fraud, the FTC collaborates with the FDA in regulating labels on food and dietary supplements. Finally, the CDC aims to control and prevent diseases, including food-borne illnesses, by investigating and monitoring pathogens (disease-causing microorganisms). The CDC uses multiple surveillance systems such as the Foodborne Disease Active Surveillance Network (FoodNet) to track food-borne diseases.

Where Are Pathogens Found?

The microbes that cause food-borne illness can be found practically anywhere—in air, water, soil, and sewage, and on various surfaces. Human skin, nasal passages, and large intestine have vast colonies of many different kinds of microbes, some of which can be pathogenic. Animals, including cats, dogs, reptiles, cattle, and poultry, can also harbor harmful microbes on and in their bodies, especially in their intestinal tracts. In addition to microbes, viruses and parasitic worms can act as pathogens. A parasite is a life form that lives on or in another organism and takes advantage of its host. Common routes for pathogenic contamination include transmission from vermin, improper personal hygiene practices, poor food-handling practices, and improper heating of foods.

Emergency Food Supply

A natural disaster can easily disrupt one's access to safe food; therefore, a person should store at least a 3-day supply of food for emergency use. Choose foods that have a long storage life, require no refrigeration, and can be eaten without cooking, such as canned meats, fruits, and vegetables. (If pets are in the household, people should also keep a supply of pet foods.) Also store batteries, flashlights, matches, a radio, a manual can opener, paper plates, and eating utensils. If stored under proper conditions, the majority of unopened canned or boxed foods will remain fresh for about 2 years beyond the date stamped on the package. Before storing food, use a permanent marking pen to write the date on the package. Use and replace foods before they lose their freshness or reach their expiration dates. An ideal food storage location is a cool, dry, dark place. Protect foods from rodents and insects by storing them in airtight containers or plastic storage bins. If there is no electricity, people should consume perishable food that is in the refrigerator or freezer before using the emergency food supply. However, discard cooked foods after they have been at room temperature for 2 hours. Do not eat food that appears or smells spoiled or is from cans that are leaking or bulging. To prepare meals safely after a disaster, store the following items: A camp stove or charcoal grill and matches. Fuel for cooking, such as charcoal. Never cook food on a camp stove or charcoal grill indoors. The fumes contain carbon monoxide, an odorless gas that can be deadly when it accumulates in small areas. Cooking and eating utensils, paper plates, cups, and towels.

Pesticides

A pesticide is any substance that people use to control or kill unwanted insects, weeds, rodents, fungi, or other organisms. There are several different kinds of pesticides. Insecticides control or kill insects; rodenticides kill mice and rats; herbicides destroy weeds; and fungicides limit the spread of fungi, such as mold and mildew. Over 5 billion pounds of pesticides are used in the United States annually. Herbicides are the most widely used type of pesticide in agriculture. The use of pesticides in modern farming practices has helped increase crop yields, reduce food costs, and protect the quality of many agricultural products. However, many pesticides leave small amounts of pesticide residues in or on treated crops, including fruits, vegetables, and grains, even when they are applied correctly. Concentrations of pesticide residues often decrease as food crops are washed, stored, processed, and prepared. Nevertheless, some of these substances may remain in fresh produce, such as apples or peaches, as well as in processed foods derived from the produce, such as canned applesauce or peaches.

Preparing for Disasters: Emergency Water Supply

A supply of clean water and wholesome food is necessary for surviving disasters such as hurricanes and earthquakes. People can be more prepared for natural disasters by storing at least 1 gallon of water per person per day. Ideally, keep at least a 3- to 5-day supply of drinking water, or at least 5 gallons of water for each person in a household. Children and breastfeeding women may need more than 1 gallon of water per day. Also, more water may be necessary for people living in warm climates. To maintain a safe emergency supply of drinking water, consumers should: Maintain the water in a cool place and in sturdy plastic bottles with tight-fitting lids. Avoid storing water in areas where toxic substances, such as gasoline and pesticides, are stored. Over time, toxic vapors from these products may penetrate the plastic and contaminate the water. Change stored water every 6 months. Drink only bottled, boiled, or treated water until certain the public water supply is safe. When there is time to prepare, people can fill a bathtub with water to use if necessary. The water, however, will need to be sanitized before being consumed. If the emergency water supply becomes inadequate or contaminated, a person can consume melted ice cubes from the freezer, canned fruit juices, and water drained from an undamaged water heater. Water stored in the tank of the toilet (not the bowl) is also fit to drink. Pets can drink toilet bowl water that has not been treated with a toilet bowl sanitizer. Water in swimming pools and spas can be used for personal hygiene needs but not for drinking. Never drink water from car radiators, home heating systems, or water beds. Alcoholic beverages contribute to dehydration and therefore should be avoided.

Storing and Reheating Food

After food is cooked, careless food handling continues to set the stage for the growth of pathogens. Food-borne pathogens thrive at "room temperature," temperatures that are between 60°F and 110°F. Although it is common practice in many homes to leave food in serving dishes and on the table for several hours after meals, to be safe, cover leftovers and refrigerate or freeze them as soon as people have finished eating, or within 2 hours. If environmental temperatures are above 90°F, refrigerate the leftovers within 1 hour. Before storing, separate the food into as many shallow pans as needed to provide a large surface area for faster cooling. There is no need to let hot foods cool on a counter before chilling or freezing them. To reduce the risk of food-borne illness, follow these food storage tips: -Check the refrigerator's temperature regularly to make sure it stays below 41°F. Keep the refrigerator as cold as possible without freezing milk and lettuce. -Cook ground meats and poultry soon after purchasing. If this is not possible, freeze the ground items. -Note that raw fish, shellfish, and poultry are highly perishable. It is best to cook these foods or freeze them the day they are purchased. -Use refrigerated ground meat and patties within 1 to 2 days, and use frozen meat and patties within 3 to 4 months after purchasing them. -Use refrigerated leftovers within 4 days. -Reheat leftovers to 165°F; reheat gravy to a rolling boil to kill pathogenic bacteria that may be present.

Bacteria

Bacteria are single-cell microorganisms that do not have the complex array of organelles that plant and animal cells contain. While the majority of bacteria require foods with moist environments, warm temperatures, and a neutral pH to grow, some species of bacteria have more unusual needs. For example, certain pathogenic bacteria can live anaerobically (without oxygen), such as in canned or vacuum-packed foods (foods packaged by removing all the air from the container before sealing), whereas other types of bacteria grow well in the cold temperature of a refrigerator. There are even a few species of bacteria that can transform into inactive resistant forms called spores when their food environment is less than ideal. If the environment becomes more hospitable, the spores revert to the active bacterial state.

Food Safety Legislation: Food Additives

By the 1950s, hundreds of ingredients were being added to foods during processing. Many of these substances had long histories of being safe; others were deemed safe after undergoing scientific testing. In 1958, the U.S. Congress enacted the Food Additives Amendment. According to this amendment, an ingredient that had been in use prior to 1958 was Generally Recognized As Safe (GRAS) when qualified experts generally agreed that the substance was safe for its intended use. The Food Additives Amendment excluded GRAS substances from being defined as food additives. Thus, modern food manufacturers can use substances on the GRAS list as ingredients without testing them for safety or getting prior approval from the FDA. Examples of GRAS substances include sucrose, acetic acid, caffeine, and guar gum According to the Delaney Clause of the Food Additives Amendment, food manufacturers cannot add a new compound that causes cancer at any level of intake. Thus, if an additive causes cancer, even though very high doses may be necessary to cause the disease, no amount of the additive is considered to be safe, and none is allowed in food. Evidence for cancer risk could come from either laboratory animal or human studies. The FDA allows very few exceptions to this clause.

Aflatoxins

Certain molds produce aflatoxins, substances that can cause severe illness, particularly liver damage, and even death when consumed. Tree nuts, peanuts, and corn that are stored under warm, humid conditions can become sources of aflatoxins. In some regions of the world, especially Africa and Southeast Asia, people often eat foods that are contaminated with aflatoxin-producing molds. Rates of liver cancer are high in these places. Thus, medical researchers think there is an association between ingestion of aflatoxins and development of liver cancer, presumably because the liver cannot excrete the toxins.

Seafood Toxins

Certain varieties of shellfish and fish, such as barracuda and grouper, are commonly associated with toxin-related food-borne illnesses. Some toxins are produced by specific types of marine algae (dinoflagellates) that accumulate in the flesh of fish or shellfish that consume the algae. Scombrotoxin results from the bacterial breakdown of fish tissue that has been improperly stored. As bacteria begin to break down the protein in fish, histamine compounds are produced. When a person consumes the spoiled fish, the high levels of histamines from the fish tissue can cause an immune response that includes allergy-like symptoms such as headaches, diarrhea, itchy skin, and a rash.

Chilling Foods

Chilling food, when done appropriately, slows the growth of microbes in the items, but some bacteria can grow even at proper refrigeration temperatures. To chill correctly, foods should be divided into shallow containers and cooled rapidly to less than 40°F. Freezing does not kill bacteria or inactivate viruses in food; the process just halts the microbes' ability to multiply. As frozen food thaws, the bacteria and viruses resume their activities and can cause illness.

Potentially Hazardous Foods and their Pathogens

Food Source Typical Menu Item Common Pathogen Beef Undercooked ground beef; steak tartare E. coli O157:H7; Salmonella species Poultry or eggs Undercooked chicken or turkey; stuffing cooked inside the bird cavity; undercooked or raw eggs or products made with these, including Hollandaise sauce, homemade mayonnaise, homemade ice cream, meringue pies Salmonella species Fish Sushi with raw fish; ceviche Anisakis; Vibrio vulnificus Shellfish Raw oysters Vibrio vulnificus; norovirus Milk and milk products Unpasteurized milk or cheeses made with unpasteurized milk Salmonella; Campylobacter jejuni; Listeria monocytogenes Produce Raw sprouts such as alfalfa sprouts; cut tomatoes or melon; leafy salad greens; prepared salads E. coli O157:H7; Salmonella; Shigella; norovirus Cooked plant food Rice; beans; tofu; potatoes or baked potato Bacillus cereus; Clostridium botulinum

Fungal Toxins

Fungi, such as molds, yeast, and mushrooms, are simple life forms that live on dead or decaying organic matter. Certain fungi, including button mushrooms and the mold in blue cheese, are beneficial and edible. Other fungi are responsible for spoiling foods, such as bread molds, or causing respiratory problems or allergic reactions in sensitive people. A serious concern is the toxicity of several varieties of wild mushrooms. Cases of severe illness and even death have been reported as a result of people picking and eating toxic wild mushrooms after mistaking them for edible varieties. It is not very common in the United States.

Food Preservation

Heating is one of the oldest ways to preserve foods. Heat can kill or deactivate pathogens, and the process also destroys naturally occurring enzymes in foods that can contribute to food spoilage. Fermentation is another ancient method of food preservation that is still used to produce a variety of foods, including yogurt, wine, cheese, and sauerkraut. The fermentation process involves adding certain bacteria or yeast to food. These microbes use sugars in the food to make acids and alcohol, chemicals that hinder the growth of other types of bacteria and yeast that can spoil food. For centuries, people preserved meats, fruits, and other foods that had high water contents by adding salt or sugar to them. Adding sugar or salt to foods draws water out of cells, including cells of bacteria, fungi, protozoa, and worms. As a result, these pathogens are less likely to survive in sugary or salty foods. Drying of foods reduces their water content, making it difficult for pathogens to grow due to the absence of moisture. Dried fruits such as raisins, for example, have a longer shelf life than grapes, their natural counterparts. Today, we can add pasteurization, refrigeration, freezing, canning, irradiation, additives, and aseptic processing to the list of food preservation techniques. Aseptic processing involves sterilizing a food and its package separately, before the food enters the package. The sterilization process destroys all microorganisms and viruses, as compared to pasteurization, which is a less extensive heating process that kills most pathogens. After undergoing aseptic packaging, boxes of sterile foods and beverages, such as milk or juices, can remain free of microbial growth for several years while sitting on supermarket or pantry shelves. However, once the containers of these products are opened, the foods or beverages have the same shelf life as their counterparts that have not undergone aseptic processing.

Public Water Supply and Safety

On many college campuses, it is common practice to see students and faculty carrying reusable water bottles, oftentimes refilling the bottles at sustainable water fountain stations on campus. Indeed, the reusable water bottle market was valued at $7 billion in 2015 with estimates that the market will reach $10 billion by 2024. The EPA regulates the sanitation of public water supplies in the United States. Most Americans can trust the safety of their tap water because the vast majority of municipal water systems in the United States are regulated by the Safe Drinking Water Act (SDWA). As a result of this law, most tap water undergoes a thorough purification process and is constantly tested for safety. Public availability of annual reports on water safety is required by the SDWA, and public notification of any violations is mandatory. If such testing indicates the water supply may pose a threat to public health, consumers are warned through media, and a "boil order"—requirement to boil water for 10 minutes to kill harmful microorganisms—may be issued.

How Safe Are Pesticides?

Pesticides help protect the food supply and make food crops available at reasonable cost. Nevertheless, pesticides have the potential to harm humans, animals, or the environment because they are designed to kill or otherwise negatively affect organisms. If a pesticide is applied improperly to cropland, it may remain in the soil, be taken up by plant roots, decompose to other compounds, or enter groundwater and waterways. Winds may carry pesticides in air and dust to distant locations. In addition, pesticides remain in the soil, in some cases for many years, after application. The potential harmful effects of a pesticide in food depend on the particular chemical and how effectively the body can eliminate it, its concentration in the food, how much and how often it is eaten, and the consumer's vulnerability to the substance. Tolerable amounts of pesticide residues on or in foods are extremely small. However, it is possible that regular exposure to small amounts of these chemicals may enable the substances to accumulate in the body and produce toxicity or initiate cancer. Health experts have studied rates of cancers among people who have close contact with pesticides, such as farmers and pesticide applicators. Among the people who applied pesticides, the likelihood of developing certain cancers, including lung, breast, prostate, non-Hodgkin lymphoma, and leukemia, was increased.

Protozoa and Parasitic Worms

Protozoa are single-celled microorganisms with a complex cell structure. Giardia and Cryptosporidium are examples of protozoa that are pathogenic to humans. Consumption of contaminated water and food, as well as contact with feces that contain protozoa, are the common routes of infection. Protozoa often live and reproduce in the tissues of their host, typically for an extended length of time before being detected. Diarrhea and other gastrointestinal symptoms are typical of infections from protozoa.

Irradiation

The process of food irradiation preserves food by using a high amount of energy (ionizing radiation) to kill pathogens such as Salmonella and E. coli. These methods do not make the items radioactive. The energy passes through the food, as in microwave cooking, and no radioactive material is left behind. The energy is strong enough to destroy the genetic material as well as cell membranes or cell walls of insects and microbes. As a result, irradiation is a highly effective way of killing insects, bacteria, protozoa, and parasitic worms that may be in foods. Irradiation, however, is not an effective way to destroy viruses or prions that may have contaminated food. Furthermore, irradiated foods, especially meats, can still become contaminated once their packaging has been opened. Irradiation extends the shelf life of spices, meats, poultry, certain shellfish, seeds, shell eggs, and fresh fruits and vegetables. Except for dried seasonings, packages that contain irradiated foods must be labeled with the international food irradiation symbol, the Radura, and include a statement indicating the product has been treated by irradiation

Preventing Cross-Contamination

To reduce the risk of food-borne illness: Hands Wash hands thoroughly with very warm, soapy water for at least 20 seconds before and after touching food. If clean water for hand washing is not available, use a hand sanitizer. If you are preparing more than one type of food, such as cutting up chicken and dicing carrots, wash hands in between. Use a fresh paper towel or clean hand towel to dry hands. Reserve dish towels for drying pots, pans, and cooking utensils that are not washed and dried in a dishwasher. Surfaces Before preparing food, clean food preparation surfaces, including kitchen counters, cutting boards, dishes, knives, and other food preparation equipment, with hot, soapy water. Sanitize food preparation surfaces and equipment that have come in contact with raw meat, fish, poultry, and eggs as soon as possible. Sanitizing is a process that uses heat or chemicals to destroy pathogens. Most pathogens on surfaces can be killed by using a sanitizing solution made by adding a tablespoon of bleach to 1 gallon of cool water.17 However, avoid getting bleach solution on colored fabrics or surfaces that can be damaged by bleach (granite, for example). Cutting boards The FDA recommends using cutting boards with unmarred surfaces made of easy-to-clean, nonporous materials, such as plastic, marble, or glass. If you prefer to use wooden cutting boards, make sure they are made of a nonabsorbent hardwood, such as oak or maple, and have no obvious seams or cracks. Replace cutting boards when they become streaked with cuts because these grooves can be difficult to clean thoroughly and may harbor bacteria. If possible, have a cutting board reserved for meats, fish, and poultry; another cutting board for fruits and vegetables; and a third board for breads.

Canned Foods

When food is canned, commercial food production methods require heating the food to certain temperatures for specified times. Thus, unless the can or jar has been damaged, properly processed canned foods should be free of pathogens. Certain home-canned foods, however, may contain the microorganism Clostridium botulinum (C. botulinum) that produces the botulism toxin. The home-canning process may kill C. botulinum bacteria in the food, but their spores or toxin may remain. That is why home-canned, low-acid foods, such as beans and corn, should be boiled for 10 minutes before eating to destroy any toxin. Foods made with vinegar, tomatoes, or citrus juices are usually high-acid foods, and as a result, such items are not likely to be sources of C. botulinum. Nevertheless, any home-canned food should be discarded if the lid has lost its seal or has "popped up."

Travelers' diarrhea (TD)

esults from consuming contaminated food or water, typically when traveling in countries where sanitary water supplies are not always available. To reduce your risk of TD when traveling to high-risk areas, the CDC suggests: -Carry alcohol-based hand sanitizer and thoroughly clean hands before eating -Avoid consuming food or beverages purchased from street vendors -Make sure meats are fully cooked before consuming -Avoid raw foods that have been washed in water before serving, such as fruits, vegetables, and salads -Avoid tap water, ice, and beverages made with ice -Consume beverages that are bottled and sealed, such as bottled water, bottled juices, and bottled alcoholic beverages -Use bottled water to brush teeth, wash hands, and take medicine.


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