HNSC Part 3
Food borne illness:
An illness transmitted to humans through food or water.
Antioxidants
Prevent the oxidation of fats, ultimately preventing discoloration of foods and fats from turning rancid. Without antioxidants, salad dressings will go rancid very quickly. e.g., Vitamin C (ascorbic acid), sulphites, butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT)
Toxin
a chemical substance that can cause damage to a biological system. Some foods, usually of plant origin, contain toxins. Plants produce toxic chemicals as a form of natural defence against animals and microbes. Other foods have naturally occurring toxins that are produced by organisms that contaminate the food. Toxicants can be found in numerous foods that we eat on a regular basis, however we only typically consume a small amount of toxins. Therefore, there is no need to eliminate these foods from our diet, as the small amounts of toxins do not present a serious health hazard. Examples of natural toxins Solanine found in potatoes has narcotic-like properties lethal levels can be reached when potatoes are diseased, bruised or exposed to sunlight during storage levels are controlled through breeding, handling and storage cooking does not destroy solanine, however, because it is present in the green layer that develops under the skin, it can be peeled off making the potato safe to eat Cyanogens compounds that contain cyanide during processing or inadequate storage the compounds can be hydrolyzed to release free hydrocyanic acid (HCN) molecules HCN is a potent respiratory inhibitor found in lima beans, fruit seeds such as apricot and peach seeds, and tubers such as cassava long-term consumption can lead to ataxic neuropathy- a group of nervous disorders Goitrogens compounds that inhibit proper utilization of iodine in the body, causing enlargement and atrophy of the thyroid gland (a condition called goiter) found in cabbage and cruciferous vegetables (broccoli, cauliflower, brussels sprouts) Marine toxins The toxins found in some fish and shell fish are not produced by the fish, but rather are caused by dinoflagellates (part of the algae family), which the fish and shellfish eat. Paralytic shellfish poisoning is caused by consuming mussels, clams and oysters that contain a toxin which produces saxitoxins. Symptoms typically develop with 30 minutes of consumption and include tingling and numbness of the fingers and lips, aphasia (incoherent speech) and inability to understand speech, because the saxitoxins bind to nerve cells and prevent the brain from transmitting signals to the muscles. Death as a result of respiratory paralysis can occur within a few hours of the onset of symptoms. The saxitoxins are heat stable, so cooking does not prevent paralytic shellfish poisoning. Ciguatera is caused by consumption of tropical herbivorous reef fish (e.g., grouper and red snapper), as well as larger fish who prey on these fish. It is heat stable, so cooking the fish does not prevent ciguatera. Symptoms develop approximately 3-5 hours after consumption and include diarrhea, nausea, vomiting and abdominal pain. Neurological symptoms typically follow, including hot/cold inversion (i.e., think that foods are the opposite temperature than they are) muscle aches, tingling and numbness of the lips, itching, metallic taste, dryness of the mouth, dizziness, chills, sweating, blurred vision, and temporary blindness. These symptoms can reoccur in an individual up to 25 years after the original poisoning. Neurotoxic shellfish poisoning is caused by consuming of clams and oysters that contain several toxins called brevitoxins. Red tide (sea water appears red) show the presence of these organisms. Symptoms include tingling, muscle aches, vomiting, and diarrhea, which disappear after a couple of days. Diarrhetic shellfish poisoning is caused by consuming of clams and mussels that contain toxins that resemble brevitoxins (the most common one is okadaic acid). The symptom is diarrhea, which typically presents a few minutes after consumption. Amnesic shellfish poisoning is caused by consuming mussels harvested from the eastern shore of Canada that contain a toxin called domoic acid. Domoic acid is an analog of the glutamic acid (an amino acid), so it binds to the glutamate receptors and causes overstimulation and eventual death of brain cells. Symptoms include irreversible short-term memory loss and disorientation, as well as vomiting and diarrhea.
Antibiotics:
used to treat infections that affect animal health. Veterinary drugs are assessed to determine their potential to leave drug residues in the meat, milk or eggs produced by the animal before they are approved for us in Canada by Health Canada. Maximum residue limits (MRLs) are set for veterinary antibiotics by Health Canada as well, while the CFIA has the responsibility to monitoring the food supply to ensure that these standards are being met. MRLs are the maximum of residue that can remain in the meat, milk or eggs that will not cause any adverse health effects in humans when consumed each day over their lifetime. Extensive, comprehensive studies are completed to assess the safety of antibiotics and the MRLs before they are approved for use. These studies look at carcinogenicity, mutagenicity, teratogenicity and the effects on the reproductive system.
Mercury
A naturally occurring element in soils, rocks, lakes, streams and oceans Pulp and paper processing, mining operations, and burning of garbage and fossil fuels can also release mercury into the environment High amounts of mercury can damage the nervous system of people and animals Mercury tends to accumulate in the food chain so that predatory species have higher levels. This is called bioaccumulation (build up of substance through food chain). Fish that are more heavily contaminated tend to be larger fish that prey on smaller fish - the mercury builds up in their system. Fish heavily contaminated with mercury: Shark Swordfish King mackerel Fresh tuna steak (Albacore) Tilefish Fish/seafood lower in mercury: Shrimp Canned light tuna (canned albacore ("white") tuna contains more mercury than light tuna) Salmon Pollock Catfish
Antimicrobial agents
Act like preservatives to prevent microorganisms from growing. E.g. Sugar and salt are the most widely used, nitrates.
Nutrient Additives
Added to fortify or maintain nutritional quality of foods (add back the nutrients lost during processing - enrichment) e.g., iodine added to salt, vitamins A and D added to milk, folic acid and other B vitamins added to breakfast cereals.
Viruses: Hepatitis A
Although viruses do not grow in foods, food can spread viral infections if it becomes contaminated. A common method of contamination is at the hands of a food preparer. Hepatitis A Hepatitis A is the sixth leading cause of foodborne illness in the U.S. It is transmitted by food, usually by fecal-oral route. This means that the food has come in contact with fecal contamination due to a food handler or contact with sewage. Shellfish that are found in polluted waters can also be a source of hepatitis A, because we eat the intact digestive tract of shellfish (therefore the contaminant - hepatitis A virus). Once a person consumes food or water contaminated with the hepatitis A virus, it typically takes about 4 weeks before symptoms are seen, however it can take anywhere from 15-50 days. The virus is shed in the feces during the time before symptoms are seen. Typical symptoms include extreme malaise, headache, nausea, abdominal discomfort, loss of appetite and may be followed by jaundice (a condition characterized by yellowing of the skin and whites of the eyes due to abnormally high levels of biliruben). The typical duration of symptoms is usually 2 weeks to 6 months, with those infected recovering without treatment. Prevention: cook shellfish thoroughly, follow proper sanitation procedures, and most importantly proper hand washing. Food service workers should not work when they are ill. There is also a vaccine to prevent hepatitis A infection
Food Intolerance:
An adverse reaction to a food that does not involve an immune response. Unlike a food allergy where the food must be completely avoided, a person can typically manage small portions of the food to which they are intolerant. Typically symptoms of food intolerance tend to be gastrointestinal in nature; gas, bloating, nausea, vomiting, diarrhea, abdominal pain.
Bovine Spongiform encephalopathy (BSE): Mad cow disease
As of 2008, there have been a dozen cases of BSE reported. BSE is an example of a transmissible spongiform encephalopathy (TSE). Transmissible spongiform encephalopathies (TSEs), are diseases that cause, brain of the victim to become riddled with holes, taking on a sponge-like (Swiss cheese) consistency. The cause of TSEs in animals and humans is a small protein known as a prion (PrP). A prion is an infectious protein particle that does not contain DNA or RNA. The prion can occur in two forms; normal conformer (PrPc, causes no problems in the body), and rogue conformer (PrPsc, causes problems). The PrPsc causes the normal PrPc to change shape, causing destruction of cells as the prion travels through the spinal cord to the brain and causes damage (holes) in the brain. Creutzfeldt-Jacob Disease (CJD) is a TSE that causes dementia in humans. Most cases effect those over 65 years of age and all cases result in death within 1-10 years. CJD incidence in the United Kingdom was low prior to 1995, at which point a new variant of CJD (nvCJD) emerged. This new form of CJD began affecting teenagers and young adults. The cause is unknown, however some scientists have linked nvCJD to the consumption of cattle infected with bovine spongiform encephalopathy (BSE), specifically spinal cord or brain material. Note that CJD itself is not linked to consumption of BSE cattle, only the new variant form. BSE is known as "mad cow disease". It is a degenerative disease in cattle that affects their central nervous system. Symptoms include convulsions, loss of coordination and behavioural changes. BSE was first seen in cattle in Great Britain in 1985 and was traced to feeding cattle bone meal from dead, diseased sheep suspected to have been suffering from Scrapie (a TSE seen in sheep that causes loss of coordination and intense itching of the animal). Because of this, Great Britain banned animal-based feed supplements for animals in 1989. Canada also implemented this same ban in 1997. Health Canada has taken many steps to reduce the risk of Canadians becoming infected by BSE, such as removing specified risk materials (SRM) from all cattle produced in Canada after they are slaughtered. SRM are the parts of cattle that are most likely to contain BSE, so these are removed so that they do not end up in the food supply. SRM are: the skull, brain, trigeminal ganglia (nerves attached to the brain), eyes, tonsils, spinal cord and dorsal root ganglia (nerves attached to the spinal cord) of cattle aged 30 months or older the distal ileum of cattle of all ages Scientific research has shown that BSE does not transfer to the muscle meat of cattle so steaks and roasts would not be affected and this meat is considered safe by Health Canada and the World Health Organization.
Food borne illness facts
Because the symptoms are so similar, Health Canada states that food borne illness can often be mistaken for a viral illness, like a 24-hour flu. The elderly, those with a chronic disease (compromised immune system), young infants and pregnant women have a greater risk of developing food borne illness, as well as having more severe symptoms and having their symptoms last for a longer period of time. There are three types of hazards that are associated with food borne illness: Biological: e.g., bacteria, mold, viruses, parasites and toxins Chemical: both naturally occurring (e.g., plant toxins) and added (e.g., antibiotics) Physical: foreign matter, e.g., glass, plastic. Of these, biological hazards (specifically bacteria) are associated with the greatest number of cases of food borne illness and death.
Celiac Disease
Celiac disease is an immune disorder that is characterized by damage to the intestinal tract caused by exposure to gluten (a protein found in wheat, rye, barley and triticale). Gluten consumption causes damage to the lining of the small intestines, impacting the body's ability to absorb nutrients. Symptoms vary from person to person, however typically include iron deficiency anemia (because of poor absorption caused by damage to the lining of the small intestine), abdominal pain, bloating, diarrhea, fatigue and weight loss. Because of the reduction in absorption of nutrients, there can also be a greater risk, long term, for osteoporosis. Some people with celiac disease also develop a skin rash (itchy and burning) called dermatitis herpetiformis. The Canadian Celiac Association estimates that 1 in 133 Canadians has celiac disease. There is some genetic link to celiac disease; about 10% of those with a relative with celiac disease will develop the disease themselves. The only treatment for celiac disease is to follow a gluten free diet for life. This means that a person with celiac disease must read food ingredient lists for all foods to determine if gluten is in the product, or phone the food manufacturer. Avoiding gluten will heal the damage to the lining of the small intestine, so that normal nutrient absorption will occur.
Artificial Food colours
Colour additives are used to make foods attractive and to identify flavours (e.g., yellow jellybeans is associated with lemon taste). Added to replace colour lost during processing or storage and to correct colour variations that can naturally occur in foods.
HACCP system consists of 7 principles:
Conduct a hazard analysis: the process of identifying the hazards that might affect a particular product in a during processing, and then collecting and evaluating information on the hazards and conditions causing the hazards to determine which are significant to food safety and must be addressed by the HACCP plan. Determine critical control points (CCPs): It involves identifying where during processing the hazards addressed in the HACCP plan can be prevented, reduced or eliminated. It is a point, step or procedure in the food manufacturing process where a control measure is essential and can be applied to prevent, eliminate or reduce a food safety hazard to an acceptable level. Establish critical limits: clearly defined and measurable criteria that separate a safe product from an unsafe product and must be established for each critical control point. Establish monitoring procedures: the process of conducting and documenting observations or measurements to determine if a CCP is under control and the critical limit is being met. Establish corrective actions: predetermined, written report of actions that are taken when CCP monitoring results indicate that a problem has occurred and there is the potential that unsafe food has been, or will be, produced. These corrective actions help to regain control of the hazard, determine how to expose of the affected product and prevent a reoccurrence of the problem. Establish verification procedures: the use of various methods, procedures, tests and other evaluations, in addition to monitoring, to determine whether the HACCP plan is being followed and control of the CCPs is being maintained. Establish record-keeping and documentation procedures: All HACCP plans, including all of the principles listed above, must be documented.
Escherichia coli 0157:H7
Escherichia coli O157:H7 is a relatively new strain of E. coli commonly found in cattle (especially dairy cattle). It lives in the large intestine of animals (e.g., cows, pigs, dogs, cats, etc.) and can also live in the intestinal tract of humans. E. coli is often referred to as "hamburger disease" because of its strong connection with beef. It can also be found in food or water that has come in contact with fecal matter (because of the fact that E. coli lives in the large intestine, it is shed in the feces of animals and people who are infected). Foods that commonly cause E. coli food poisoning include raw or undercooked meat (e.g., ground beef should be cooked to an internal temperature 71°C, so a meat thermometer should be used - typically the meat and juices are no longer pink) and raw (unpasteurized) milk (may contain bits of fecal debris from the udder of the cow). Unpasteurized fruit juices can also be a source. Unlike other bacteria, E. coli is a surface contaminant, meaning that it is only found on the surface of the food product and does not penetrate into the centre. This is why it is safe to eat a steak that is pink in the middle, but it is not safe to eat a hamburger or meat loaf that is pink in the middle. On the steak, the E. coli would only be on the outer surface, so as long as the outsides are cooked, it is safe to eat with pink still in the middle. With ground meat products the meat has been ground, so the surface is now throughout the entire product, so the entire product has to be fully cooked. Once a person consumes food or water contaminated with E. coli, it typically takes about 12 - 18 hours before symptoms are seen, however it can take up to 8 days in some cases. Typical symptoms include nausea, vomiting, watery and bloody diarrhea (because of hemolytic colitis), abdominal pain, and dehydration. In more severe cases, headache, muscle cramping, and temporary changes in blood pressure and pulse rate may occur. Although it is rarely fatal, it could be fatal in infants, elderly and those with a compromised immune system. The typical duration of symptoms is usually 2 - 9 days, with most people recovering without treatment. However, about 2-7% of cases lead to a condition called hemolytic uremic syndrome, which can cause acute kidney failure, resulting in a need for dialysis and in some cases, blood transfusions in ICU. Prevention: cook meat thoroughly, especially ground meat, pasteurize milk and fruit juices, avoid cross contamination, e.g., do not use platters that held raw meat for cooked food, proper hand washing, and appropriate kitchen clean up.
Norwalk viruses (Noroviruses)
First recognized in 1968 in Norwalk, Ohio, with school outbreak where water was the suspected source. Shellfish, water contaminated with sewage and infected food handlers can spread these viruses. Heating will destroy the virus, so mainly seen in ready to eat foods that do not require heating prior to consumption. Once a person consumes food or water contaminated with the Norwalk or Norovirus, it typically takes about 1-2 days before symptoms are seen, however symptoms can be seen as quickly as 12 hours in some cases. The virus is shed in the feces during the time before symptoms are seen, and can be found in the stool and vomit during illness and for several days after recovery. Typical symptoms include nausea, vomiting, and diarrhea (gastroenteritis), as well as fever, headache and stomach pain. The typical duration of symptoms is 1-2 days. It is often known as the stomach flu and is highly contagious. These viruses can survive fairly high levels of chlorine (so bleach solutions are not necessarily effective in killing the virus) and can have high survival rates on surfaces, such as door handles, sinks, counters, railings, etc. Prevention: cook shellfish thoroughly, follow proper sanitation procedures, and most importantly proper hand washing. Food service workers should not work when they are ill. Outbreaks caused Norovirus are commonly seen in areas where people are in close contact, including hospitals, schools, personal care homes, daycares and cruise ships.
What do microorganisms need to grow?
Food Acid (~4.6-7.0 pH) Temperature 4°C (40°F) - 64°C (140°F) is called the "danger zone" Time (more than 2 hours) Oxygen (however some microorganisms are anaerobic, so do not need oxygen) Moisture We can control microbial growth by: decreasing pH keeping foods refrigerated at 4°C (40°F) or lower, or heated above 64°C (140°F) not leaving food out at room temperature for more than 2 hours wrapping food tightly to avoid contact with oxygen drying foods
HACCP
HACCP was initially developed in the USA to ensure safety of foods to be used in the space program. It is a preventive system that significantly reduces production of unsafe food products. It is food safety protocols involving the manufacturing environment, food handling personnel, equipment and food itself that food processers and manufacturers follow, which is based on risk assessment and the identification of critical control points. Critical control points are points during the food production process that need to be controlled to ensure the safety of the food product.
Symptoms of food borne illness:
Headache Nausea Vomiting Diarrhea Dehydration Abdominal pain Fatigue Fever
HACCP was designed for 3 reasons:
Identify hazards that could occur to foods during their preparation Identify control steps in food production that ensure a safe product Monitor these steps to ensure they are being controlled
Environmental contaminants/ pollutants
Include industrial pollutants, toxic metals and contaminants from packaging. Routine monitoring of chemical contaminants is carried out and a ban is imposed if levels are too high. How harmful a contaminant is depends on how long it persists in the environment or in the human body. Some contaminants do not breakdown and are difficult for our body to metabolize or excrete. These contaminants are concerning because they can build up and accumulate at higher and higher concentrations along the food chain.
Food borne illness can be caused be infection or intoxication:
Infection: multiplies and infects tissues in the body bacteria multiply and infect tissues (e.g. the intestinal tract causing damage to the epithelial cell lining) imbalance of osmotic pressure occurs, resulting in diarrhea damaged cells in intestinal tract signal the brain to trigger vomiting fever occurs onset of symptoms takes 12 hours to 2 days on average e.g., Salmonella, Shigella Intoxication: produce toxins as they multiply which cause harm to tissues bacteria that produce toxins in the food or in the body as they multiply toxins grow if food is not stored properly these toxins can cause damage to the cells that line the intestinal tract, and can travel to the kidneys and cause damage there onset of symptoms takes a few hours; very fast e.g., Staphylococcus aureus, Clostridium botulinum
Heavy Metals
Lead: displaces minerals, causing function failure of kidneys, liver, nervous system, bone marrow. Mercury Cadmium: causes slow developing, irreversible damage to the liver and kidneys. Selenium Arsenic: used as a medication for animals. Can also be found in lower quantities in fish, eggs, milk, rice and drinking water.
According to Health Canada, the nine most common food allergies in Canada are:
Peanuts Eggs Milk Tree nuts Wheat Soy Sesame seeds Seafood (fish, shellfish and crustaceans) Sulfites These foods account for about 90% of food allergies in Canada. Allergic reactions to single foods are most common—reactions to multiple foods are very rare. A family history of allergies can increase the risk. Breastfed babies are at lesser risk of developing allergy when compared to formula- fed infants. It is not recommended that a woman avoid specific foods during pregnancy to reduce the risk of the baby having a food allergy unless she is allergic to the food(s) herself. If children do develop food allergies, they are frequently outgrown by the age of 7. Only about 30% of children with a food allergy will continue to allergic to that food in adulthood. Food allergies can also develop in adulthood and are often linked to environmental allergies. Lab tests (e.g., skin prick tests or blood tests), along with diet history and history of symptoms are required to identify true allergy. Another way to test for a food allergy is a 'challenge test' where a person would be given a small amount of the foods suspected as the allergen in a controlled setting (i.e., there are medical professionals available if a serious allergic reaction occurs). Once identified, the only treatment for food allergies is to avoid the food and any foods that contain that ingredient. The food ingredient list on packages can be a source of information, In August of 2012, enhanced food labelling requirements can into effect to make it easier for consumers with food allergies to identify specific ingredients in a food product.
Indirect (Incidental) Food Additives:
Physical additives E.g. pieces of glass, plastic, paper, metal, packaging, etc. Accidentally introduced during processing E.g. in November of 2011, the Canadian Food Inspection Agency issued a Health Hazard Alert for Woody's brand Mexican Lime Alcoholic Vodka Beverages because they may have contained glass fragments. Chemical additives: Methylene chloride Used to remove caffeine in the production of decaffeinated tea or coffee. Traces are left in the decaffeinated product. An average cup contains 0.1 parts per million which poses no significant health hazard. Dioxins Compounds formed during chlorine treatment of wood pulp during paper manufacture. Found in coffee filters, milk cartons, paper plates and frozen food packages. Contamination occurs only in trace quantities (in parts per trillion range) and these levels appear to pose no health risk to humans. Chemicals leached from plastic containers when used inappropriately E.g. using a margarine tub to store leftover food, and then heating in the microwave. When heated, particles from the tub can migrate into the food. Make sure that you check your containers to ensure that they are microwave safe before using them in the microwave. Bisphenol A (BPA)
Handling of Leftovers
Refrigerate leftovers promptly. Follow the 2-hour rule, foods should be stored in the fridge within 2 hours of preparation. Store leftovers in small shallow dishes, using several if necessary. When food is put into a large container, it is not able to cool to 40*C quickly enough to prevent microorganisms from growing. Remove stuffing from poultry and store separately (the safest way to cook stuffing is separate from the bird, to ensure that it reaches a high enough internal temperature). Reheat foods adequately (so solid foods should be steaming, and liquids should boil). Discard foods past their expiry date or past their safe food storage time. Do not consume food that is suspect. Follow the principle of "when in doubt, throw it out". For mold growth, discard soft foods with mold (e.g., bread, fruit). For solid foods (like brick cheese), you need to trim off at least 1 inch off past where any mold has grown, as mold will inject toxins into the food that cannot be seen on the surface.
Salmonella
Salmonella is the leading cause of food borne illness in North America; the Food and Drug Administration estimate that there are 2-4 million cases annually of salmonellosis (the disease caused by Salmonella). Salmonella bacteria can be found in the environment (water, soil, insects), in animal feed and in the intestines of animals (especially poultry). Foods or equipment that is exposed to animal waste is at risk for being contaminated with Salmonella bacteria. You can come in contact with it through the following foods: Meat - raw or undercooked, especially poultry - Ideally, poultry should be cooked to an internal temperature of 77°C (ground poultry 80°C), However most people do not have meat thermometers, so we have to rely on visual cues (like cooking chicken until no pink remains in the meat or juice). Eggs - raw and undercooked and their products (e.g., homemade Caesar salad dressing, raw cookie dough). Undercooked eggs are when the white and yolk are not fully firm (e.g., sunny side up, over easy). Use pasteurized eggs in these products, because the pasteurization process kills the Salmonella and other bacteria. Unpasteurized (raw) milk and milk products such as milk cheeses (e.g., some soft cheese like feta can contain raw milk) Sprouts (uncooked seed and bean sprouts) Unwashed raw fruits and vegetables and their products (e.g., unpasteurized juice or cider) Human feces can also be a source. Once a person is infected with Salmonella, it is shed their feces. Contaminated foods typically do not look, smell or taste any different. Thorough cooking of foods kills Salmonella, as does a disinfectant cleaner or sanitizer (e.g., bleach) used on countertops, cutting boards, knives, etc. Cross contamination is the transfer of bacteria from one food to another, or from a surface to a food (or vice versa). An example of this would be cutting raw chicken on a cutting board and then using the same knife and cutting board to cut lettuce without cleaning it properly in between. This could result in the transfer of Salmonella to the lettuce which is a ready to eat food (meaning that we are not going to cook it before eating it. Cooking or using a disinfectant are the ways to kill Salmonella, so since we are not going to put bleach on our lettuce, we will end up ingesting that Salmonella and potentially getting sick. Once a person consumes food or water contaminated with Salmonella, it typically takes about 1-3 days before symptoms are seen . Typical symptoms include nausea, headache, diarrhea, abdominal pain, chills, fever, vomiting and dehydration, and it can be fatal in infants, elderly and those with a compromised immune system. The typical duration of symptoms is 1-4 days, however they can last up to 7 days, with most people recovering without treatment. Long term complications can include severe arthritic symptoms. Prevention: cook eggs and poultry thoroughly, pasteurize milk, irradiate chicken, proper hand washing, appropriate kitchen clean up, avoid cross contamination.
Food safety at home: Shopping
Shop last during outings so food items do not sit in your car. In the grocery store, buy perishable items last. Get perishable foods into the refrigerator or freezer as soon as possible. On a hot day, pack perishable foods in a cooler or insulated bags with ice packs. Don't buy it if you won't use it before expiry date. Buy foods in good condition.
Bisphenol A (BPA)
Specific regulations exist for some packaging materials with limits set on levels permitted and migration limits. There has been a lot of media attention on Bisphenol A (BPA), which is a chemical used in the production of hard, clear plastic called polycarbonate. Polycarbonate is used in a variety of food containers (e.g., reusable water bottles, infant bottles, food storage containers, outdoor table wear and glasses). BPA is also used in the production of epoxy resins, which are used to line the inside of food and beverage cans. Small amounts of BPA may leach out into the food or water stored in these containers, however this exposure is of no risk to Canadians, with the exception of newborns and infants, where the level of exposure can reach that seen in animal studies to cause adverse health effects. The effects seen in animal research have shown that BPA can have estrogen-like activity in the body and may be an endocrine-disrupting agent. The recommendations that Health Canada gives to parents are: Do not put boiling or very hot water into polycarbonate baby bottles (as this can cause BPA to leach at a higher rate). Allow boiled water or liquids to cool to lukewarm before placing in the baby bottle. Allow polycarbonate bottles to cool to room after sterilization / cleaning before adding infant formula. If a parent is concerned about using polycarbonate baby bottles, there are numerous alternatives available in the marketplace that do not contain polycarbonate plastic. To identify if a plastic container or bottle had polycarbonate plastic, the only means available currently is to check to see if your container has a recycling symbol on the bottom. Polycarbonate plastic fits in the "other plastic" category for recycling, which is classified by the number '7'. However, polycarbonate is not the only "other plastic" that fits in this category, so this does not mean that there is for sure BPA in the plastic. If the symbol on the bottom is '7 PC' this indicates polycarbonate plastic. These recycling symbols are not mandatory on plastic containers, so may not be found on your bottle or container. Lack of these recycling symbols does not mean that there is no polycarbonate plastic (BPA) in the container.
Food safety at home: Storage
Store foods promptly. Refrigerator temperature not higher than 4°C or 40°F (use a fridge thermometer to determine the temperature of your refrigerator). Freezer temperature not higher than -18°C (0°F) Freeze meat if you can't use it within a couple of days. Prevent raw juices of meat from dripping on other food by storing in the bottom of your refrigerator. Do not store foods for too long.
Food Additives:
Substances added to food either intentionally or by accident that become part of the food and affect its characteristics (like colour or flavour). Most food additives are done purposely (intentional additives), including sugar, colourings, salt, baking soda, etc. Some additives however are contaminants that are accidently introduced (indirect / incidental additives). These substances can be accidently introduced to the food during the production, processing or packaging process. Food additives have been used for thousands of years; salt used as a preservative for meats, vinegar used to pickle vegetables, spices used to enhance flavours.
The Canadian Food Inspection Agency (CFIA)
The CFIA enforces the standards and policies set by Health Canada related to foods sold in Canada. They work from farm to table, meaning that they enforce standards from the point where the food is grown, through to the point that it ends up on your kitchen table. The CFIA is responsible for: Controlling animal diseases and pests Stop diseases and pests from entering Canada Control or eradicate diseases if they do occur Inspect farmers' fields and imported plants Able to quarantine animals This helps to reduce the risk of invasive alien species (IAS). IAS are animals, plants and micro-organisms that can cause damage to Canada's natural ecosystem when they are introduced to a new area, or in a different distribution. Inspecting foods Register and inspect all food processing plants. Monitor imported foods to ensure they meet Canadian requirements. Coordinate the food recall program for foods recalled due to food safety risk or undeclared ingredients. Test foods for chemical residues. Preventing fraud Enforce labelling laws. Check quantities, verify composition, and grade. Regulate seeds, feed and fertilizers Protects Canadians from unfair production practices. Diagnosing problems Identify problems in food products. Develop rapid methods for detecting food pathogens. Enforcing safety standards Work with provincial and municipal inspectors. Respond to security threats to Canada's food supply, agricultural resources and forests.
Clostridium botulinum
The Clostridium botulinum toxin is very potent. 1 tsp could wipe out the population of New York City. Clostridium botulinum is an anaerobic bacteria (meaning it does not survive in oxygen) found widely distributed in nature; soil, water, on plants, in intestinal tract of animals and fish. It produces the most powerful known toxin which blocks nerve function. The paralytic illness caused is called botulism. Clostridium botulinum can be found in improperly home canned or commercially canned foods (e.g., leaky, bulging, dented or broken cans), especially low acid home canned foods (e.g.,vegetables). Because it is an anaerobic bacteria, it is found in things that are tightly sealed with little oxygen (e.g., canned goods, flavoured oils). Dented canned goods can have microscopic holes that can allow bacteria in. Products with bulging cans should never be consumed, it is the bacteria growing inside that is producing gas, causing the can to bulge. Also, if a can hisses or the contents shoot out when opened, it should be thrown away. It is important to properly clean any surface in your kitchen that has come in contact with these food materials with a disinfectant or sanitizer (e.g., a dilute bleach and water solution). Honey can also be a natural source of Clostridium botulinum spores (almost like a hibernating form of Clostridium botulinum; not in an active period of growth), however it is not in levels that would be harmful to most people. Have you ever heard of not feeding honey to babies? This is because babies lack the immunity (mature digestive tract) needed to protect against these spores that can cause infant botulism. Mature adults are usually protected against this threat but infants under one year of age should never be fed honey, which can also be contaminated with environmental pollutants picked up by bees. Once a person consumes the Clostridium botulinum toxin, it typically takes about 12 - 24 hours before symptoms are seen, however it can be as long as 72 hours before symptoms present. Typical symptoms include double vision, inability to swallow, speech difficulty and progressive paralysis, which can result in death. Long term complications can include fatigue and shortness of breath. Treatment is required to prevent death; a person must have an anti-toxin administered. Not all strains of Botulism are killed at boiling temperature. The toxin is killed at 100°C so proper cooking is key. Botulism spores are killed at 120°C (for 10 minutes). Therefore, it is important to cook and reheat foods properly. Prevention: sterilize canned foods. Home canned foods should be processed using a pressure cooker. Home canned foods should be boiled for 10 minutes prior to consuming to increase safety.
Food safety at home: Serving
Use clean dishes. Never place cooked food on a surface that has held raw meats, fish or poultry (e.g., taking raw patties out to the barbeque on a plate and then putting the cooked burgers back onto that same plate to serve). Never leave perishable foods out of refrigerator for more than 2 hours (as microorganisms will have had too long to multiply in the food).
Food safety at home: Preparation
Use good quality ingredients (e.g., not expired, pasteurized milk and juices, etc). Use sanitary equipment (so ensure equipment is clean prior to use). Clean counter tops prior to food preparation. Ensure cutting boards and knives are clean. Wash hands with soap and water before preparing food. See Figure 12.4: Proper Hand Washing Prevents Illness in your NCC Supplement. Replace dish cloths, towels and sponges often (they can harbour microorganisms and spread them to other surfaces in your kitchen, so should be changed on a daily basis. Have you seen the commercial on television where the lady whips down her kitchen with a piece of chicken? That can literally be what your dish cloth/sponge can be like if you have used it to wipe up chicken juice and then wipe down your counters with it). Avoid cross contamination. Rinse cutting boards with sanitizing solution (e.g., dilute chlorine bleach and water solution) to prevent growth of microorganisms. Fight BAC recommends a solution containing 1tsp bleach in 3 cups water. Wash raw produce prior to use. See Table 12.7: Produce Safety in your NCC Supplement. Thaw foods safely: - in the refrigerator (bottom shelf) - in cold water (either under running cold water or in a cold water bath in the sink - water needs to be changed every hour to avoid the temperature rising above 4°C) - in the microwave (food must be cooked immediately after thawing, as microwaves tend to heat food unevenly) Cook high risk foods like ground meat, poultry, fish and eggs thoroughly. Use a meat thermometer to ensure proper temperature is reached.
Artificial Flavours
Used to enhance flavour of foods A rtificial flavours are the largest group of food additives e.g., monosodium glutamate (MSG) and hydrolyzed vegetable proteins. In Canada MSG is considered an ingredient and not an additive, but it must be declared on the label. Not allowed in foods designed for infants. MSG imparts a taste called umami (savoury) to foods. Some people experience adverse reactions when the consume MSG. These adverse reactions are classified as MSG Symptom Complex, as include headache, flushing of the chest and face, and burning sensations.
Growth hormones:
Used to enhance the growth of specific cells and increase food efficacy in animals (meaning that there is more muscle in the animal and less fat, so more to be sold for human consumption). Growth hormones are permitted for use in Canada and the United States, however they are prohibited in the European Union. Scientific evidence however does not show any adverse health effects to humans from consuming animals treated with the growth hormones approved for us in Canada. Growth hormones are only permitted in beef cattle in Canada, and there are currently 3 natural hormone promoters and 3 synthetic hormone promoters approved for use. Growth hormones are injected into the cattle (typically behind the ear), with the exception of one synthetic hormone promoter that can be added to the cattle feed. The use of growth hormones in beef helps to keep beef prices reasonable for consumers. If they were not used, the cost to produce the same amount of beef would be higher, therefore the cost to purchase beef would be higher as well. The growth hormone bST (bovine somatotropin) is not permitted to be used for milk cows in Canada. In Canada, the use of growth hormones are regulated, however this is not the case all over the world. In Puerto Rico, there are cases of children as young as 7 who are physically adults, thought to be a result of growth hormones used in chicken. Hormone use is not permitted in chickens in Canada.
Health Canada and the Canadian Food Inspection Agency
Work together to ensure that the Canadian food supply is safe. Agriculture and Agri-Food Canada, and Environment Canada also play a role in monitoring the food supply in Canada. The greatest health risk from food is microbial contamination [bacteria, fungi (molds & yeasts), parasites and viruses]. Canada has one of the safest food supplies in the world.
Anaphylaxis / Anaphylactic shock:
a life threatening reaction to a food substance that affects multiple body systems. The symptoms of anaphylactic shock include swelling of the throat, difficulty breathing, circulatory collapse, abdominal cramps, vomiting, diarrhea, coma and death. Symptoms tend to develop rapidly, and to treat anaphylaxis, epinephrine (also called adrenaline) is administered via injection (e.g., EpiPen®) at the initial onset of symptoms. It is recommended that those who suffer from anaphylaxis carry epinephrine with them at all times. After the epinephrine has been administered, the person needs to go immediately to the hospital for thorough assessment and further treatment.
Pesticides:
chemicals used to control, prevent or eliminate the growth of insects, and other pests. Include herbicides (which are to control, prevent or eliminate the growth of unwanted plants, such as weeds), insecticides (used to control, prevent or eliminate insects) and fungicides (used to control, prevent or eliminate the growth of mould and fungi). Pesticides are regulated under the Pest Control Products Act by Health Canada. Before being approved for use in Canada, research is done to ensure that it is safe for human health and for the health of the environment, and to prove that it is effective. This is important, because in some cases residues of the pesticide can remain in or on the food. During this process, an Acceptable Daily Intake (ADI) for the pesticide is also determined, as well as acceptable pesticide residue levels regulated by establishing Maximum Residue Limits (MRLs). The ADI is the maximum amount of the pesticide that could be consumed each day over a person's lifetime without risk for adverse health effects, and the MRLs help to ensure that human consumption of a pesticide stays below the ADI. After approved for use, pesticides are re-evaluated for safety every 15 years. The use of pesticides is also monitored to ensure that they are used safely and responsibly.
Food Allergy
involves an immune response to a food substance (specifically the proteins in that food) called antigens.< In Canada, food allergies affect about 5-6% of children and about 3-4% of adults. When a person has a food allergy, their immune system mistakes the protein in a food for being harmful, and so the body makes antibodies called immunoglobulin E (IgE) the first time it is exposed to the protein. Then, when the body is re-exposed to that food protein, the IgE is released, along with histamine, which can cause reactions in the skin (e.g., hives, itching), respiratory system (e.g., runny nose, difficulty breathing), gastrointestinal tract (vomiting, diarrhea), cardiovascular system (e.g., drop in blood pressure), and oral cavity (swelling of the lips/tongue, itching and irritation of the mouth, swelling and tightening in the throat). Food allergies can be serious enough to cause death in some cases. The most severe symptom seen is called anaphalaxis, which affects about 1-2% of Canadians.
Lactose intolerance
is a condition characterized by impaired ability to digest lactose due to reduced amounts of the enzyme lactase. As we age, approximately 75% of the world's population lose their ability to produce lactase and therefore their ability to digest lactose. Those of Northern European background have the lowest rates or lactose intolerance (only approximately 15% of the North European population are lactose intolerant). People with lactose intolerance experience some amount of nausea, pain, diarrhea and gas. The undigested lactose draws up water (causing diarrhea) and the bacteria in the colon use the undigested lactose for energy (causing gas and intestinal irritation). Many people can tolerate some lactose, only a rare few cannot tolerate lactose in any amount. Consuming lactose containing foods with meals can help, because food slows the transit of foods through the digestive tract. Yogurt and aged cheese are often tolerated because the bacteria or molds used to ferment these products digest lactose. Products treated with lactase (e.g., Lactaid milk) can be purchased, as can lactaid pills and drops, which replace the missing enzyme.
The Safe Food for Canadians Act:
makes food as safe as possible for Canadian families; protects consumers by targeting unsafe practices; implements tougher penalties for activities that put health and safety at risk; provides better control over imports; institutes a more consistent inspection regime across all food commodities; and strengthens food traceability."
Purposes of food additives
provide leavening (e.g., baking powder and baking soda allow breads and cakes to rise during baking) control acidity/alkalinity (important for food safety to control microbial growth, as well as for the flavour, taste and colour of the food) enhance flavour (can be natural e.g., fruit extracts, spices; or synthetic e.g., artificial sweeteners) impart desired colour (this helps to enhance the appearance of food so that it meets our expectations as consumers - for example, most mint chocolate chip ice cream is green in colour. If the green colouring was left out and we were presented with white ice cream with chocolate bits, we would probably not expect the ice cream to taste of mint. Colourings can be synthetic or natural. improve or maintain nutritional quality of foods (through the addition of nutrients) maintain product consistency (e.g., prevent the food product from separating - salad dressings for example have food additives that prevent the oil and water from separating) maintain palatability and wholesomeness (e.g., preservatives added to extend the shelf life of foods)
Polychlorinated biphenyls (PCB's)
refer to a group of at least 50 widely used compounds containing chlorine that can accumulate in the food chain and cause a variety of harmful effects (fatigue, eye irritation, growth retardation in children when exposed prenatally). They are man-made and were banned in North American in 1977. They can still be found remaining in the environment, because they do not break down and are difficult to destroy. So we are still exposed to small amounts of PCB's, typically through food consumption. The levels we are exposed to however are well below what Health Canada determines could cause adverse health effects.
Staphylococcus aureus
taphylococcus aureus is a common bacterium present in the nasal passages, throats and on the hair and skin of 30-40% of healthy people and animals. The bacteria can cause boils, pimples, other skin infections and toxic shock syndrome. Staphylococcus aureus can also be found in the air, dust, sewage, water, milk, food or on food equipment (e.g., meat slicers not properly cleaned), environmental surfaces. Food handlers are usually the main source of food contamination in food poisoning outbreaks. Contamination comes from people preparing food while they have colds / sore throats (sneezing or coughing near food), eye infections, or infected skin cuts (important to wear gloves). Foods at highest risk of contamination with Staphylococcus aureus and subsequent toxin production are those that are made by hand and require no cooking. People can pass on the Staph aureus bacteria, however people sick with the toxin are not able to pass on the toxin to others. Staphylococcus aureus has the ability to make seven different toxins that are frequently responsible for food poisoning (Staph. aureus is responsible for 20-40% of all cases of food poisoning). It is the toxin produced by the bacteria that actually causes illness. Staph. aureus multiply rapidly at room temperature to produce toxins that are resistant to heat and cannot be destroyed by cooking. The bacteria itself can be killed by very high heat (121°C in moist heat for at least 15mins, dry heat - 160-170°C for at least 1 hour). It can also be killed by a sanitizing agent. The toxins produced however are heat resistant and stable at boiling temperature, so will not be killed by boiling a food. Foods frequently contaminated include meats, poultry, egg products, salads/sandwich fillings with mayonnaise (e.g., egg, tuna, chicken, potato, and macaroni), bakery products such as cream-filled pastries, cream pies, and chocolate éclairs, and milk / milk products. Once a person consumes food or water contaminated with Staph. aureus, it typically takes about 30 minutes to eight hours before symptoms are seen. Typical symptoms include nausea, vomiting, diarrhea, abdominal pain, and dehydration. In more severe cases, headache, muscle cramping, and temporary changes in blood pressure and pulse rate may occur. Although it is rarely fatal, it could be fatal in infants, elderly and those with a compromised immune system. The typical duration of symptoms is usually 24 - 48 hours, however they can last up to 3 days, with most people recovering without treatment. Prevention: not allowing infected persons to prepare food, thorough heating and cooling of food, proper hand washing, appropriate kitchen clean up, avoid cross contamination.
Mycotoxins
toxins produced by molds growing on foods. Molds can typically be seen on foods because of their fuzzy growth (bloom). They grow best at room temperature, however need less moisture to grow than bacteria do. Toxin production is stimulated at lower temperatures (-1 to -10°C). There have been over 300 mycotoxins identified, some of which are carcinogenic (cancer causing). Symptoms of mycotoxins range from food borne illness symptoms (e.g., nausea, vomiting), to kidney disorders, liver cancer, bone marrow destruction and gangrenous ergotism, a condition characterized by a burning sensation in the hands and feet. This condition can progress to loss of circulation, and can result in amputation. One of the best known mycotoxin is aflatoxin, which is made by the mold Aspergillus flavus. This mold can infect nuts (especially peanuts), flour, wheat and soybeans. Aflatoxin is a potent liver carcinogen. Prevention: it is difficult to completely avoid contamination. Therefore, health regulations permit small levels in foods.