This document discusses various biological hazards in food known as biohazards. It describes different types of biotoxins produced by living organisms like bacteria, fungi, algae, and plants that can cause food intoxication. Specific toxins are produced by organisms like Staphylococcus, Aspergillus, and Clostridium. These toxins can contaminate foods like meats, nuts, grains and cause illness. The document outlines the toxicity levels, symptoms and food sources of major toxins like botulinum, aflatoxin, ochratoxin and patulin. It emphasizes the importance of good agricultural practices, storage, handling and processing to control these biological hazards in foods.

1. Food borne Biohazards

2. Biotoxins
• Biotoxin is a poisonous substance that is a
specific product of the metabolic activities of a
living organism (Plant, animal, bacteria,
fungus).
• Cause food intoxications
• Toxicity depends on dose

3. Food Intoxication
• Microbes grow in foods produce toxins.
• Toxins are ingested with the food and cause
health problems.
• Most heat treatments are effective to kill
microbes, but toxins remain

4. Toxin classification
Organism
Toxin
Bacteria
Botulinum toxin, Staphylococcus toxin
Fungi
Afalatoxin, Mycotoxin, Ochratoxin, Patulin
Toxic algae
Okadaic acid
Natural toxins
Histamine, Glycoalcoloids

5. Toxin characteristics
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Non replicative (Most are proteinaceous)
Non transmittable (human to human)
Nonvolatile
Colorless
Odorless
Tasteless
Most are stable at standard conditions

6. Botulism toxin
• Agent: Chlostridium botulinum
• Toxicity: 1ng/kg
– 500g is enough to kill the human race
• Disturb the acetylecholine mechanism at
neuromuscular junctions
• Symptoms
– Nausea, vomiting, diarrhea, headache, lethargy,
double vision, respiratory stress, death

7. Food sources
• Improperly canned foods (>pH 4.6)
• Smoked salmon, trout
• Fermented foods (Saeurkraut, pickled
vegetables)
• Foods preserved in oil (Fish)

8. Staphylococcus toxin
• Agent: Staphylococcus aureus
• Toxicity: 1μg cause illness
• Disturbs the regulation of intestinal fluid
regulation system
• Symptoms:
– Sudden nausea, vomiting, excessive salivation,
abdominal cramps, diarrhea, dehydration
• Toxin is heat stable

9. Food sources
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Cooked ham, meat products, poultry
Home made sausages
Milk, cheese
Cream filled pastries

10. Afalatoxin
• Agent: Aspergillus flarus
• Afalatoxin B1, B2, G1, G2 (B1 is the most
common)
• Toxicity: 0.5-10 mg/kg
• Liver cancer, chronic hepatitis, jaundice,
cirrhosis (Low levels long time)
• Cause acute toxicity, and potentially death
(High exposure)

11. Food Sources
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Peanuts and peanut butter
Tree nuts such as pecans
Corn
Wheat
Oil seeds such as cottonseed

12. Ochratoxin
• Agent: Aspergillus ochraceus
• Toxicity: No documented acute toxicity in
humans
• Tolerable weekly intake 120ng/kg (EFSA)
• Has genotoxic and teratogenic effects
• Relatively heat stable

13. Food Sources
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Soy beans
Coffee beans
Grapes
Peanuts
Cereals

14. Patulin
• Agent: Aspergillus clavatus. Penicillium
expansum
• Toxicity: No documented acute toxicity
• Provisional maximum tolerable daily intake
0.4μg/kg
• Relatively heat stable and not destroyed by
pasteurization

15. Food Sources
• Apple and apple juice
• Pears, grapes, bilberries may affect
• Sweet cider

16. How to control
• Good agricultural practices to avoid insect
damages and mold infection
• Good storage practices (Store below 100C,
control moisture, control RH)
• Separation of contaminated foods before
processing

17. How to control
• Follow proper food handling and canning
methods
• Maintain good hygienic practices
• Rules and Regulations

18. Referenes
• http://www.foodsafetywatch.org/category/fac
tsheets/biotoxins/