Food Safety and Foodborne Illnesses
Truvia sweetener
Extracted from leaf of Stevia plant ~2x as sweet as sugar
Treatments and Supplements
Food additives and veterinary drugs
Fertilizers
Nitrogen, others
Prevention Foodborne Disease
Safe cooling and cold holding temperatures Keep foods above 140˚F for hot foods and below 40˚F for foods that are kept in cold storage. The range between 40˚F and 140˚F is the danger zone.
Paralytic shellfish poison
Shellfish become toxic to humans when they feed on dinoflagellates such as Gonyaulax catenella (saxotoxin) Symptoms of tingling or burning of lips and gums, ataxia, and paralysis of diaphragm
Norvirus Symptoms
Signs/symptoms Nausea, vomiting, abdominal cramps Diarrhea Fever, chills, body aches Last 1-2 days
Delaney Clause
prohibited use of additives determined to cause cancer in human beings or animals
How?
". . . illnesses acquired by consumption of contaminated food. . ." Frequently called food "poisoning"
Foodborne Outbreak
"...the occurrence of a similar illness among two or more people which an investigation has linked to consumption of a common meal or food items, except for botulism (one case is an outbreak)."
Nitrates and Nitrites
(Food Additive) *Prevent growth of Clostridium spores *In the body, nitrates can be reduced to nitrites which in turn oxidize hemoglobin and cause anoxia. *In food, nitrites react with amines, to form nitrosamines. *Have caused cancer of the liver, kidney, bladder, stomach, and pancreas of laboratory animals. *Amount of nitrites added to meat has been reduced *Addition of ascorbate or sodium erythorbate can prevent formation of nitrosamines
Significant Regulations
*1906 Food and Drugs Act *The Federal Food, Drug, and Cosmetic Act of 1938 *Miller Pesticide Amendments, 1954 *Food Additives Amendment, 1958 *Color Additive Amendments, 1960 *Animal Drug Amendments, 1968 *Food Quality Protection Act (FQPA), 1996
Salmonella Symptoms and Treatment
*Acute symptoms (onset time 6-48 hours) Nausea Vomiting Abdominal cramps Diarrhea Fever Headache *Chronic symptoms May include arthritic-like symptoms that occur 3-4 weeks after an acute infection Treatment *Rehydration in non-immunosuppressed Ciprofloxacin in adults; other antibiotics in children
Noroviruses (previously Norwalk-like viruses or calicivirus illness)
*Cause ~90% of epidemic non-bacterial outbreaks of gastroenteritis worldwide *50% of all foodborne outbreaks of gastroenteritis in the US (~23 mil. cases) *Transmitted easily within closed environments such as cruise ships *Transmitted person-person or foodborne
Food Additives
*Considered least hazardous source of foodborne illness *Rank behind pesticides, environmental contaminants, natural toxins, and microbial toxins >Intentional (direct) additives: To improve their quality (taste, color, texture, shelf life). *Incidental (indirect) additives: >May be present as result of unintentional contamination during packaging, storage, and handling. >Malicious additives: Substances such as poisons that saboteurs introduce into foods
Salmonella Sources
*Endemic in wild and domestic animal reservoirs *Animals for human consumption—poultry, swine, cattle—may harbor Salmonella. *Pet animals such as cats, dogs, and turtles also reservoirs for Salmonella *Some animals and birds are chronic carriers of the bacteria.
E. coli
*Enteroinvasive E. coli Invade the epithelial cells of the intestine Causes fever, chills, and watery (more common) or bloody diarrhea More common in LDCs Humans are reservoir Usu. treated with rehydration therapy *Enterotoxigenic E. coli Produce toxin Cause traveler's diarrhea Exhibit cholera like symptoms (treated same) Humans are reservoir *Enteropathogenic E. coli Most commonly found in infant nurseries in developing countries Virtually confined to infants less than 1 yr. Rehydration therapy *Enterohemorrhagic E. coli Also known as E. coli O157:H7 Result of consuming improperly cooked ground beef, raw milk, or unpasteurized apple cider Reservoirs: cattle; humans; deer? Rehydration therapy if needed; specific antibiotic treatment of questionable value
Contributing Factors
*Explosive growth of cities after the Civil War and the expansion of transportation led to an organized food industry *Fresh meat and produce became available year-round via refrigerated railcars, trucks, and air freight A*dulteration of foodstuffs prevalent in 18th and 19th centuries to maximize profit *Additives unregulated; colorings and flavorings sometimes poisonous *Changes in agricultural and food processing methods *Rearing cattle/poultry (high pop. density) *Antibiotics *Use of pesticides/fungicides Increasing globalization in food distribution *Human social and behavioral changes Fast foods Longer shelf life Packaging
Regulation of Food Safety
*Food and Drug Administration (FDA) is the U.S. agency charged with regulation and enforcement of food safety. *U.S. Department of Agriculture (USDA) regulates the safety of meat and poultry products.
Employment Roles in Food Safety
*Restaurant inspectors oversee the safety of foods served in local restaurants. *Epidemiologists investigate outbreaks of foodborne illness in their communities. *Microbiologists identify microbes that may be present in foods. *Federal government employs inspectors who are involved with the processing of food animals.
Antimicrobials in Meat
*Similar or identical to those used by humans *Used for disease prevention and growth enhancement among animals (cattle, swine, poultry, and fish). *Some U.S.-approved antimicrobials given to food animals: amoxicillin penicillin bacitracin erythromycin
Clostridium perfrigens Effects
*Symptoms Intense abdominal cramps Diarrhea Onset 8-22 hrs after consumption of toxin-contaminated food *Duration Approximately 24 hrs Mild symptoms may last for 1-2 weeks *Treat with rehydration
Surveillance efforts
*The CDC Foodborne Diseases Active Surveillance Network (FoodNet) (http://www.cdc.gov/foodnet/) *Objectives: Determine the burden of foodborne illness in the United States Monitor trends in the burden of specific foodborne illness over time Attribute the burden of foodborne illness to specific foods and settings Develop and assess interventions to reduce the burden of foodborne illness
Intentional Additives: Preservatives
*To prevent growth of microbes such as bacteria, yeasts, and molds *Antioxidants Prevent fatty foods from acquiring a rancid taste Prevent some foods from turning brown Reduce the loss of vitamins. *Some antimicrobial preservatives: Nitrates (e.g., sodium nitrate) BHA and BHT Disodium EDTA Sulfites Proprionates Parabens
Growth Hormones
*Traces of antibiotics - used routinely to prevent rapid spread of disease among animals raised in close quarters *Growth hormones *Used with 90% of cattle in U.S.; smaller percent of sheep; use in cows adds over $80 extra profit per animal; leaner meat with less feed *Recombinant bovine growth hormone (rBGH) and recombinant bovine somatotropin (rBST) used in dairy cows every 14 days to boost milk production 10-20% Endocrine effects?
Cryptosporidium (Protozoans)
*Transmitted primarily via water contaminated with feces from humans and agricultural animals *Also person-person; animal-person *Foodborne transmission occurs via the fecal-oral route, usually from careless food handlers shedding the hardy oocysts (see life cycle, next Fig.) *Outbreak in Milwaukee, 1993 ~400,000 cases Contaminated water supply *Incubation period: 1-12 d. (~7) *In healthy individuals, symptoms present as: Mild diarrhea and cramps Nausea Low grade fever *Immunocompromised patients: High volume diarrhea Severe abdominal cramps Weight loss Can be fatal Treatment: none specific; rehydration
Heavy Metals
*high concentrations, heavy metals can cause vomiting that occurs a few minutes to several hours (most cases <1 hour) after ingestion. *Acidic conditions will leach these chemicals from damaged packaging containers Antimony Cadmium Lead *Mercury Methyl mercury is an acute toxin which causes tremors, neurological complications, kidney failure, and birth defects. Fungicides and animal feed
HACCP (7 principles)
1. Analyze hazards. 2. Identify critical control points. 3. Establish preventive measures with critical limits for each control point. 4. Establish procedures to monitor the critical control points. 5. Establish corrective actions to be taken when monitoring shows that a critical limit has not been met. 6. Establish procedures to verify that the system is working properly. 7. Establish effective recordkeeping to document the HACCP system.
Food colors and Flavorings
1. pickles colored bright green with copper, 2. candies and sweets tinted with lead and copper salts, 3. commercially baked bead whitened with alum 4. beer froth produced by iron sulfate.
Name of Minamata Bay, Japan
1953-61 on Island of Kyushu Vinyl chloride manuf. dumped inorganic mercury into bay Bacteria in sediments converted to organic form Contaminated fish and accumulated up food chain Affected cats, then people 1,000 people died; 2,000 affected
Saccharin (Sweet-n-Low)
200-700x sweeter than sugar Non-caloric Thought to promote bladder cancer in lab animals exposed to carcinogen Not covered under the Delaney clause Prohibits use of any additive proven to cause cancer in lab animals No longer considered carcinogenic
Aspartame (Nutrasweet; Equal)
200x sweeter than sugar Not non-caloric, but amounts used are so low, it is considered as same
Sucralose (Splenda)
600x sweeter than sugar No calories
Chemically related Foodborne Hazards
80-90% of exposure to potentially harmful chemicals via food Toxins Heavy metals Pesticides, herbicides, and fungicides Veterinary medicines in meat Additives used for various purposes Chemicals Enter food from: Packaging materials (e.g., bisphenol A, BpA) Agricultural applications of pesticides and fertilizers Adding preservatives or colorings Release of industrial chemicals into the environment (see next Table).
Global Burden
A major cause of morbidity (and sometimes mortality) in the USA and other countries Incidence of foodborne illnesses has increased in industrialized nations. 1.5 billion children under 5 suffer from diarrhea, and over 3 million die as a consequence (worldwide)
Affects / Consequences / Costs
Affects ~33-76 million persons each year Estimated 9,000 deaths annually Economic cost of $5 billion annually Medical costs Loss of wages/productivity Product recall Investigation Source tracking Litigation
Plant Sources of Poisons
Alkaloids (some plants' defense mechanism from insects, herbivores) Herbs -the pyrrolizidine group (coltsfoot, confrey, petasite) Potatoes- Solanum alkaloids Caffeine, teas- Xanthine alkaloids (harmful if ingested at high levels) Jimsonweed (Datura stramonium) - tropane alkaloids: atropine, hyoscyamine, scopolamine (deliriants; anticholinergics)
BSE Outbreak
An outbreak in 1986 affected 1 million cattle in U.K. Reported in 20 European countries as well as Japan, Israel, and Canada Cases have been reported in the U.S. (2003 and later). Appears to be spread among cattle by feeds that contain rendered cattle products
Pesticides in Foods
Applied to crops to reduce insects, weeds, fungi; may leave residues Dietary sources are a principal means of exposure to persistent organic chemicals, Organochlorine pesticides (chlorinated hydrocarbons) Polychlorinated biphenyls (PCBs) Many chemicals banned from use in the U.S. are sold to developing nations who use them extensively in producing crops for export to American market.
Scombroid toxin (histamine poisoning)
Bacterial growth and breakdown of meat reacts with amino acids to produce histamine Espec. tuna, mahi-mahi, bluefish, others
Hazard Analysis of Critical Control Points (HACCP)
Began in the 1950s System for reducing the risk of foodborne illness Mandated by fed. govt. for seafood, poultry, other meat industries Using HACCP, foods are monitored from the time of harvest to the time of consumption.
Food Hazard (4 major Categories)
Biological (pathogens, poisonous plant/animal products) Physical (e.g., stone, glass, metal, radiation) Chemical (heavy metals, pesticides, additives) Nutritional (presence of nutrients and other food constituents in excess or deficient amounts that lead to disease)
Adulterated Foods
C18 and C19 included 1. black pepper mixed with mustard seed husks, pea flour, juniper berries, or floor sweepings 2. tea with leaves of the ash tree which were dried thorn leaves, curled, and sold.(green tea and black tea) 3. cocoa powder enriched with brick dust 4. milk supplies extended with water 5. coffee blend with ground acorns or chicory
Clostridium perfringens
CDC estimates ~10,000 cases/yr in U.S. C. perfringens is anaerobic, rod-shaped, and forms spores Occurs commonly in the environment (e.g., in soil and sediments), especially in areas contaminated with feces Also found in the intestines of human and animals
Surveillance in US
CDC maintains responsibility at the federal level. FoodNet -CDC Foodborne Diseases Active Surveillance Network An active system whereby public health officials maintain frequent, direct contact with clinical laboratory directors to identify new cases of foodborne illness.
Causes of Food Outbreaks
Causes of illness in 1,565 single food commodity outbreaks, 2003-2008
GRAS (Generally Recognized as Safe)
Chemicals that had a history of safe use before the 1958 Food Additive Amendment passed Permitted the use of additives that had an established history of safe use in foods There are approximately 700 GRAS substances. The FDA reviews their safety and reclassifies as necessary.
Monosodium Glutamate
Chinese Restaurant Syndrome (headaches, possible nausea, diarrhea, and lesions of the retina) An allowable daily intake (ADI) of 120mg/kg has been established for individuals over one year of age. Not used in infant foods
Marine toxins
Ciguatoxin Scombroid toxin (histamine poisoning) Paralytic shellfish poison Puffer fish toxin (tetrodotoxin)
Reasons for Prevalence
Climate (warm vs. cold) Population demographics (e.g., crowding; elderly and infants) Nutritional status (and immunity) Cultural aspects (e.g.,...) Food choices (contaminated meat) Food preparation (un- or under-cooked meat)
Staphlococcus common causes
Common cause of outbreaks at picnics, church suppers, wedding receptions, restaurant meals Treatment: supportive
Staphylococcus contamination occurs
Contamination occurs through the preparation of foods by infected food handlers. Foods such as creams, cream pies, potato salad, and ham have all been implicated in outbreaks of Staphylococci food poisoning.
Beaver Fever (Giardia lamblia)
Cysts reach surface freshwater through fecal deposits of beaver ("beaver fever"), other wild animals Humans are also reservoirs Contact with animal feces (incl. pets) Symptoms may include: Abdominal cramps; bloating Frequent (up to ten movements per day) loose, pale, greasy stools Fatigue Weight loss Malabsorption of fat soluble vitamins Treatment: metronidazole (Flagyl)
Insecticides
DDT, PARATHION, PYRETHRUM, ASENICALS, OTHERS
Food Additives Amendment, 1958
Delaney Clause—prohibited use of additives determined to cause cancer in human beings or animals Repealed by the Food Quality Protection Act, 1996 Abolishing the zero cancer risk standard for pesticide residues in some processed foods--with a single "safe" standard of a reasonable certainty of no harm to consumers for pesticide residues in raw and processed foods.
Fungicides
Dithiocarbamates, mercurial, others
Irradiation of Foods
During the process, energy from ionizing radiation passes through foods and destroys bacteria and other pathogens. Procedure does not cause food to become radioactive. Referred to as cold pasteurization Certified as a safe method for reducing the risk of foodborne disease
E. Coli 0157:H7
E. coli O157:H7 73,000 cases and 61 deaths annually in U.S. Major outbreaks in restaurant chains Can be transmitted by many vehicles Symptoms generally include: Abdominal cramps Watery to bloody diarrhea Vomiting Possibly fever and; Hemolytic uremic syndrome (HUS), the primary cause of renal failure in children
Food Additives Legislation
Food and Drug Act of 1906 Due to increasing knowledge of effects of long-term chemical exposure In 1958, the Food Additive Amendment to the Food Drug and Cosmetic Act required FDA testing and approval before use (included the Delaney Clause). Color Additive Amendment of 1960
Creutzfeldt-Jakob Disease (vCJD)
Form of the disease in humans Risk of transmission of BSE to humans appears to be low.
Ciguatoxin
From larger fish that eat small fish that feed on plankton that produce toxin
Puffer fish toxin (tetrodotoxin
Genus Fugu Toxin inactivated if prepared in acid or alkaline conditions
Saponins
Glycosides that hemolyze red blood cells (detergent-like) Dietary shift to healthier foods such as alfalfa and soy based products may increase saponin intoxications
Eschericia coli (E. coli)
Gram negative E. coli that are important to foodborne illness divided into four groups: (1) enteroinvasive (2) enterotoxigenic (3) enteropathogenic (4) enterohemorrhagic Many E. coli strains are non-pathogenic
Cholera (Vibrio cholera)
Gram negative vibrio Responsible for the disease cholera which is common among LDCs and international travelers In Peru, in 1991, an outbreak of cholera spread to 322,562 people One of ancient "plagues" Outbreaks in London in 1800s John Snow's classic investigations
Importing
Importers of food to U.S. are responsible for ensuring safety of products Facilities that produce, store, handle the products must be registered with FDA Prior notice of incoming shipments Imported food products subject to FDA inspection
Glucosinolates
In broccoli, cabbage, radish, horseradish, mustard greens May cause hypothyroidism (goitrogens)
Unintended Chemicals Found in Food
Insecticides Fungicides Fertilizers Treatments and Supplements Accidential and Invertent Migration from Packaging Chemcals resulting from processing or preparation
Accidental and Inadvertent
Mercury, PCBs, lead, dioxin, aluminum and cadmium from kitchenware
Metal Poisoning Sources
Metals can leach into foods (esp. acidic foods) from metal containers Candy wrappers made with lead Chicken may contain high levels of arsenic; used as approved food supplement for chickens to control intestinal parasites Some fish—shark, swordfish, king mackerel, tilefish, tuna—have enough mercury to be harmful to developing human fetuses.
Chinese Restaurant Syndrome
Monosodium Glutamate (headaches, possible nausea, diarrhea, and lesions of the retina) An allowable daily intake (ADI) of 120mg/kg has been established for individuals over one year of age. Not used in infant foods
Multistate outbreak
Multistate Outbreak of Shiga Toxin-producing Escherichia coli O26 Infections Linked to Raw Clover Sprouts at Jimmy John's Restaurants
Botulism Effects
Onset of symptoms usually 18 to 36 hours after ingestion of contaminated food; range from 4 hours to 8 days Early signs: Marked lassitude Weakness and vertigo Double vision Progressive difficulty in speaking and swallowing Difficulty breathing Abdominal distention Constipation A single case is important; may indicate group outbreak Treat with IV botulinum antitoxin
Lectins
Plant proteins (Leguminosae family) that agglutinate red blood cells Ricin toxin of castor bean
Beef tapeworm (Taenia saginata)
Principal features of the beef tapeworm (Taenia saginata). The head, or scolex, contains suckers and hooks for attaching to the host. A series of reproductive organs (proglottids) continually form at the base of the neck, and following fertilization they mature and break off. Each proglottid, eliminated in the host's feces, contains thousands of embryos to continue the life cycle.
Bovine Spongiform Encephalopathy (BSE)
Prions are hypothesized to be the cause of bovine spongiform encephalopathy (BSE), a neurological disease in cattle. The course of BSE is progressive, ultimately fatal, and is potentially transmissible among cattle.
Giardiasis intestinalis (aka lamblia)
Protozoan flagellate found in areas with poor sanitation, and in unfiltered surface water "Giardiasis" is most common among: Travelers to more highly endemic areas Homosexuals Child day care settings Hikers/campers
Use of Antimicrobials is a Potential Problem
Residues of antimicrobial agents may persist in meat for human consumption. Antimicrobial resistant infection in human consumers, leaving them unable to use therapeutic intervention to kill bacterial infections.
Bacterial Agents
Responsible for 80% of foodborne illness Unicellular organisms that have characteristic shapes, e.g., rod-shaped, spherical (cocci), or spiral.
Clostridium botulinum
Spore-forming, anaerobic bacillus; common in soil, marine sediments, fish Causes botulism, a rare but very serious foodborne intoxication Produces potent neurotoxin Associated with improperly processed or damaged canned foods Must boil canned foods for 10 min.
Effects of Infection with Tapeworms
Symptoms of taeniasis usually are limited to mild abdominal distress Main symptom is passage of proglottids (section of the worm that contains eggs) in stools Possible cysticercosis with T. solium (larvae invade muscle, brain, liver, other tissues) Treatment: Praziquantel or Albendazole
Agents of Foodborne Morbidity and Mortality
The causative agents and modes of transmission are known in less than 1% of the severe gastroenteritis cases.
Salmonella
The infection is called salmonellosis. *Salmonella bacteria are: Rod-shaped Motile Gram-negative Non-spore forming *Most common serotypes in U.S. are: Salmonella serotype enteritidis Salmonella serotype typhimurium *Ranked among the most frequent types of foodborne illness in the U.S. ~2 to 4 million cases of salmonellosis (reported and non-reported) estimated each year in the U.S. Causes about 500 deaths each year*
Prevention of Growth Foodborne Pathogen
Thorough hand washing Prevention of cross-contamination Use of sufficiently high cooking temperatures Storage of foods at proper temperatures in a refrigerator
Salmonella Transmitted
To environmental surfaces at work and at home (e.g., the kitchen) from raw meats, poultry, and seafood Also cross-contamination From animal feces From contaminated water and soil
Poisonous plants and animals
Trial and error process to identify plants that were harmful or of nutritional value Some plants and animals known to be harmful have significant nutritional value and are still part of diet Naturally occurring toxins, such as those from seafood and mushrooms, may be associated with foodborne illness.
Cholera
Vibrio cholerae colonizes lining of the intestine; produces the toxin choleragen Symptoms: Abdominal pain Profuse, watery diarrhea ("rice water stool") Dehydration; electrolyte imbalance Death possible Treatment: primarily rehydration therapy 1. wash hands with soap and water 2. Put 1 litter of clean water in clean pot 3. Empty contents of packet into water while stirring 4. Give the sick child as much of soln as possible
Hepatitis A
Viral Agent Picornavirus (positive strand RNA virus) Foods associated commonly with HAV outbreaks include produce, cold cut sandwiches, dairy, shellfish Common mode for food contamination: HAV-infected workers in food processing plants and restaurants Of the 23,000 cases of hepatitis A reported in the U.S. annually, about 7% are believed to be food or waterborne; other high risk groups Day care centers Homosexual males Injection drug users
Trichinosis (roundworm - nematode)
a foodborne disease from eating meat that contains a nematode (roundworm) from the genus Trichinella Classic agent of trichinosis is Trichinella spiralis, found in many carnivorous and omnivorous animals (e.g., swine, bears, walruses, rodents, and cougars) Signs/symptoms: diarrhea, abdom. pain, vomiting; muscle pain; eosinophilia Treatment: Albendazole or Mebendazole; steroids
Taeniasis (tapeworms - cestodes)
a parasitic disease caused by tapeworms (cestodes) One form is caused by the beef tapeworm (Taenia saginata) and the other by the pork tapeworm (Taenia solium) These organisms may induce human illness following consumption of raw or undercooked infected beef or pork
Staphylococcus supp.
another bacteria Staphylococcus food "poisoning" caused by the gram-positive cocci, Staphylococcus aureus. *Sickness is due to the consumption of the heat stable enterotoxin, and includes nausea, vomiting, and diarrhea *Humans and animals are reservoirs. *Present in the nose and skin lesions *Produces a heat resistant toxin *Frequent cause of foodborne outbreaks *Causes foodborne intoxication with rapid onset Incubation period ~4-6 hrs. Dose-dependent Duration of symptoms ~24-48 hrs.
Adulteration
biggest scandal of C19 food establishments involved in widespread practice; deliberate intention of inferior or cheaper material to a supposedly pure food product in order to stretch out supplies and increase profits.
Prions
hypothesized to be the cause of bovine spongiform encephalopathy (BSE), a neurological disease in cattle. The course of BSE is progressive, ultimately fatal, and is potentially transmissible among cattle.
Adulteration Scandal with China
in 2007 American pet owners prompted pet food recall - 14,000 dogs and cats China supplied chap nitrogen-containing plasticizer that makes the glutens protein content appear higher than it actually is and thereby increased profits.
Contaminants
include dirt, hairs, animal feces, fungal growths, insect fragments, pesticide residues, traces of growth hormones or antibiotics and so on, that are introduced into food during the harvesting, processing or packaging stage.
Pure Food and Drugs Act
passed in 1906
Migration from packaging
plastics, stabilizers such as alkylphenols, printing inks, tin, and lead
Chemicals resulting from processing or preparation
polycyclic aromatic hydrocarbons (PAHs), nitrosamines, mutagens
rBGH
recombinant Bovine Growth Hormone or rBST is injected into daily cows every 14 days resulting in 10-20% inc in milk production;
rBST
recombinant Bovine Somatotropin is injected into dairy cows every 14 days resulting in 10-20% inc in millk production. 1999 Canadian regulatory agency for food safey prohibits sale of rBST and by 2000 most Europen countries as well as Austrlia and New Zealand had done likewise; US remains as the only major country allowing use of rBGH as safe; Kroger, Costco, Safeway and Walmart choose to not carry milk produced with rBST;.
Defect action levels
specifying maximum limits of contamination at or above which the agency will take action to remove the product from the market Examples on page 217