Chapter 2 Hazards - Biological, Chemical, Physical

Objective u Awareness of: –Biological hazards –Chemical hazards –Physical hazards u Characteristics of certain microorganisms

Hazard u A biological, chemical or physical agent that is reasonably likely to cause illness or injury in the absence of its control

Hazards u In HACCP, “hazards” refer to conditions or contaminants in foods that can cause illness or injury. It does not refer to undesirable conditions or contaminants such as: –Insects –Hair –Filth –Spoilage –Economic fraud and –Violations of regulatory food standards not directly related to safety

Hazards u Biological u Chemical u Physical

Biological Hazards u Microorganisms –Yeast –Mold –Bacteria –Viruses –Protozoa u Parasitic worms

Microorganisms u Microorganisms can be beneficial, even essential u Some microorganisms can be pathogenic. It is this class that concerns food processors and public health officials

What do microorganisms (other than viruses) need? u Food u Water u Proper temperature u Air, no air, minimal air

Many pathogenic microorganisms reproduce by dividing in two u When they grow, microorganisms produce by- products –Yeast - bread, beverages, fruit –Lactic acid bacteria - yogurt, cheese, meats –Staphylococcus aureus - enterotoxin u Most spoiled foods do not present a health risk, and not all food that appears normal is safe to consume

Spoilage or Decomposition u Food spoilage or decomposition that can result in a food safety problem should be prevented or controlled by a HACCP program

Microbiological hazards include harmful: u Bacteria u Viruses, and u Protozoa

Bacterial Hazards u Food infection and food intoxication u Sporeforming and nonsporeforming bacteria

Sporeforming Bacteria (Pathogens) u Clostridium botulinum –Proteolytic –Nonproteolytic u Clostridium perfringens u Bacillus cereus

Nonsporeforming Bacteria u Brucella abortis, B. suis u Campylobacter spp. u Pathogenic Escherichia coli (e.g., E. coli O157:H7) u Listeria monocytogenes u Salmonella spp. (e.g., S. typhimurium, S. enteriditis) u Shigella spp. (e.g., S. dysinteriae) u Pathogenic Staphylococcus aureus (e.g., coagulase positive S. aureus) u Streptococcus pyogenes u Vibrio spp. (e.g., V. cholerae, V. parahaemolyticus, V. vulnificus,) u Yersinia enterocolitica

Hazards from Viruses in Foods u What are viruses? u Where do they come from? u How do they reproduce? u How can they be controlled? u What are some examples? (Table A)

Viral Hazards u Very small particles that cannot be seen with a light microscope u Do not need food, water or air to survive u Do not cause spoilage u Infect living cells and are species specific u Reproduce inside the host cell u Survive in human intestines, water or food for months u Transmission usually by fecal-oral route and related to poor personnel hygiene

Parasites in Foods u Parasites are organisms that need a host to survive u Thousands of kinds exist worldwide, but only about 100 types are known to infect people through food contamination u Two types of concern from food or water: –Parasitic worms [e.g., roundworms (nematodes), tapeworms (cestodes), flukes (trematodes)] –Protozoa u Role of fecal material in transmission of parasites

Parasitic Protozoa and Worms u Roundworms (nematodes) –Anisakis simplex –Ascaris lumbricoides –Pseudoterranova dicepiens –Trichinella spiralis u Tapeworms (cestodes) –Diphyllobothrium latum –Taenia solium, T. saginata u Flukes (trematodes) u Protozoa –Cryptosporidium parvum –Entamoeba histolytica –Giardia lamblia

Chemical Hazards u Naturally Occurring u Intentionally added u Unintentionally added

Types of Naturally Occurring Chemical Hazards u Mycotoxins (e.g., aflatoxin) u Scombrotoxin u Ciguatoxin u Shellfish toxins –Paralytic shellfish poisoning (PSP) –Diarrhetic shellfish poisoning (DSP) –Neurotoxic shellfish poisoning (NSP) –Amnesic shellfish poisoning (ASP)/Domoic Acid

Intentionally Added Chemicals - Food Additives u Direct (allowable limits under GMPs) –Preservatives (e.g., nitrite and sulfiting agents) –Nutritional additives (e.g., niacin, vitamin A) –Color additives (e.g., FD&C Yellow No. 5)

Unintentionally or Incidentally Added Chemicals u Agricultural chemicals –e.g., pesticides, fungicides, herbicides, fertilizers, antibiotics and growth hormones u Prohibited substances (21 CFR, Part ) u Toxic elements and compounds –e.g., lead, zinc, arsenic, mercury, cyanide u Secondary direct and indirect –e.g., lubricants, cleaning compounds, sanitizers, paint

Physical Hazard u Any potentially harmful extraneous matter not normally found in food –Glass –Wood –Stones –Metal –Plastic