FOOD HAZARDS

Definition of Hazards

A biological, chemical or physical agent that is reasonable likely to cause illness or injury in the absence of its control is called hazard.

as mentioned in the definition, there are three types of Hazards:

  1. Biological Hazards
  2. Chemical Hazards
  3. Physical Hazards

BIOLOGICAL HAZARDS

Organisms are too small to be seen with the bare eyes, therefore they are called micro-organisms. They live everywhere like air, dirt, fresh and salt water, skin, hair, animal fur and plants. They are classified into three groups:

  • Bacteria
  • Viruses
  • Protozoa

There are thousands of kinds of micro-organisms exist, only a few pose hazards to humans. Many microorganisms are beneficial.

Certain kind of yeast, molds and bacteria help to make cheese, sour cream, yogurt and other fermented dairy products. there are particular kind of yeasts are used to make beer, wine or other fermented beverages.

one microorganisms splits into two, two into four, four into eight and so on.

once the food is spoiled, it may not look, smell or taste good but only food spoiled by pathogens or contaminated by toxic microbial by products can make a person ill.

By doubling, microorganisms multiply quickly. Under ideal conditions, some bacteria double every 20 minutes. Potentially, one microorganism can multiply to more than 30,000 in five hours and to more than 16 million in eight hours.

Fortunately, most microorganisms grow more slowly than this, and we can slow them even more by controlling the food, water and temperature that they need to grow and multiply.

BACTERIAL HAZARDS

  • Bacterial hazards are defined as those bacteria that, if they occur in food, may cause illness in humans, either by infection or intoxication. Foodborne infections are caused by swallowing live pathogens that grow within the body, usually in the intestinal tract.
  • They differ from food-borne intoxication, which is a condition caused by swallowing preformed toxins (i.e., toxins produced by microorganisms in the food before it is eaten). Bacterial hazards can also be grouped into sporeformers and nonsporeformers.
  • Certain types of bacteria (e.g., Clostridium and Bacillus spp.) pass through a dormant stage in their life cycle called a spore. Although the microorganism exists as a spore, it is very resistant to chemicals, heat and other treatments that would normally be lethal to nonsporeforming bacteria. Because they are dormant, spores are not hazardous as long as they stay spores.
  • Unfortunately, if they survive a processing step designed to kill nonsporeforming bacteria, they may become a hazard in the food if they are allowed to grow. When sporeformers are a concern, the process steps used to control them are often much more severe than if only nonsporeformers need to be controlled.

SPOREFORMING BACTERIA, EXAMPLES:

  • Clostridium botulinum Proteolytic Nonproteolytic
  • Clostridium perfringens
  • Bacillus cereus

NONSPOREFORMING BACTERIA, EXAMPLES:

  • Brucella abortis, B. suis
  • Campylobacter spp.
  • Pathogenic Escherichia coli (e.g., E. coli)
  • Listeria monocytogenes
  • Salmonella spp. (e.g., S. typhimurium, S. enteriditis)
  • Shigella spp. (e.g., S. dysenteriae)
  • Pathogenic Staphylococcus aureus
  • Streptococcus pyogenes
  • Vibrio spp. (e.g., V. cholerae, V. parahaemolyticus, V. vulnificus)
  • Yersinia enterocolitica

VIRUS HAZARDS

  • Like other microorganisms, viruses exist everywhere. They are very small particles that cannot be seen with a light microscope and cannot reproduce by themselves.
  • Although they are alive, viruses differ from other microorganisms in what they need to live and how they multiply.
  • Viruses exist in foods without growing, so they need no food, water or air to survive. They do not cause spoilage.
  • Viruses cause illness by infection. They can infect living cells and reproduce inside the host cell using material from it.
  • Viruses only grow once they enter a suitable host. Only some viruses consider humans a suitable host. Viruses can survive in human intestines, contaminated water and frozen foods for months
  • Hepatitis A: Causes fever and abdominal discomfort, followed by jaundice.
  • Norwalk virus: Causes nausea, vomiting, diarrhea and abdominal pain (gastroenteritis). Headache and low-grade fever may also occur.

PARASITIC HAZARDS

  • Parasites are organisms that need a host to survive, living on or within it. Thousands of kinds of parasites exist worldwide. Only about 20 percent can be found in food or water, and less than 100 are known to infect people through consumption.
  • There are two types of parasites that can infect people through food or water: parasitic worms and protozoa.

  • Parasitic worms include

    • Roundworms (nematodes),
    • Tapeworms (cestodes) and
    • Flukes (trematodes)
    • These worms vary in size from barely visible to several feet in length. Protozoa are single-cell animals, and most cannot be seen without a microscope.

CHEMICAL HAZARDS

  • Compounds that can cause illness or injury due to immediate or long-term exposure.
  • Chemical contamination can happen at any stage in food production and processing. Chemicals can be helpful and are purposefully used with some foods, such as pesticides on fruits and vegetables. Chemicals are not hazardous if properly used or controlled.
  • Potential risks to consumers increase when chemicals are not controlled or the recommended treatment rates are exceeded. The presence of a chemical may not always represent a hazard.

  • Chemical hazards can be separated into three categories:

    • Naturally occurring chemicals.
    • Intentionally added chemicals.
    • Unintentionally or incidentally added chemicals.

NATURAL OCCURING CHEMICALS:

  • These chemicals are derived from a variety of plants, animals or microorganisms. In most cases, these naturally occurring chemicals are found prior to or during harvest.
  • Certain fish species: Spoilage of certain species of fish can (e.g., tuna, mahi-mahi) result in production of toxic levels of histamine and related compounds.
  • Nuts, Seafood: Certain varieties or species produce an allergic reaction in sensitive people.
  • Corn: Certain molds that grow on corn can create toxins (e.g., aflatoxin).
  • Molluscan shellfish: Some of the microscopic organisms and plants upon which they feed can produce a toxin, such as domoic acid, that affect people but not shellfish.

TYPES:

    • Mycotoxins (e.g., aflatoxin)
    • Scombrotoxin
    • Ciguatoxin
    • Shellfish toxins

INTENTIONALLY ADDED CHEMICALS:

  • These chemicals are intentionally added to food at some point during the food’s growth and distribution.
  • Intentionally added chemicals are safe when used at established safe levels but can be dangerous when those levels are exceeded.
  • FD&C Yellow No. 5: Can produce an allergic-type reaction in (food coloring) sensitive people.
  • Sodium nitrite: Can be toxic in high concentrations. (preservative)
  • Vitamin A: Can be toxic in high concentrations. (nutrient supplement)
  • Sulfiting agents: Can cause allergic-type reaction in (preservative) sensitive people.

Direct (allowable limits under GMPs)

  • – Preservatives (e.g., nitrite and sulfiting agents)
  •   – Nutritional additives (e.g., niacin)
  •   – Color additives

UNINTENTIONALLY OR INCIDENTALLY ADDED CHEMICALS:

  • Chemicals can become part of a food without being intentionally added. These incidental chemicals might already be in a food ingredient when it is received. For example, certain seafood may contain small but legal residues of approved antibiotics.
  • Packaging materials that are in direct contact with ingredients or the product can be a source of incidental chemicals, such as sanitizers or inks.
  • Most incidental chemicals have no effect on food safety, and others are only a concern if they are present in too high an amount.
  • Incidental chemicals also include accidental additions of prohibited substances such as poisons or insecticides that may not be allowed at any level.

EXAMPLES: Agricultural chemicals (e.g., pesticides, fungicides, herbicides, fertilizers, antibiotics and growth hormones)

  • Prohibited substances (Code of Federal Regulations, Chapter 21, Section 189)
  • Toxic elements and compounds (e.g., lead, zinc, arsenic, mercury, cyanide)
  • Secondary direct and indirect – Plant chemicals (e.g lubricants, cleaning compounds, sanitizers, paint)

PHYSICAL HAZARDS

  • Foreign objects in food that can cause harm when eaten, such as glass or metal fragments.
  • include any potentially harmful extraneous matter not normally found in food. When a consumer mistakenly eats the foreign material or object, it is likely to cause choking, injury or other adverse health effects.
  • Physical hazards are the most commonly reported consumer complaints because the injury occurs immediately or soon after eating, and the source of the hazard is often easy to identify.
  • Glass: Cuts, bleeding; may require surgery to find or remove.
  • Metal: Cuts, broken teeth; may require surgery to remove.