Aflatoxin

1
Aflatoxin

• By Brad Burkholder
• February 7, 2006

2
Background

• Fungal kingdom - derived from mold
• Mycotoxin
• Aspergillus flavus
• Various types depending on fluorescence
• B1, B2, G1, G2, M1,
• and M2

3
Discovery/Common Exposure Methods

• England 1960 - first isolated and ID
• 100,000 turkeys died
• Brazilian peanut meal
• Various exposure methods
• Contact with fungus
• Types of food
• Contaminated animal feed

4
Symptoms

• Onset of high fever, progressive jaundice,
  weakness, tachycardia, edema
• nausea, headache, rash
• Hepatitis B and malnutrition
• geographic correlation

5
Toxicity Mechanisms

• Mostly unclear
• Exposure estimation difficult
• Primary target organ liver
• Genotoxic potential/oncogenes
• DNA damage and gene mutation
• LD50 range 0.5 - 10 mg/kg body weight
• 20 ppb max. level for human consumption

6
Metabolism

• 8,9-epoxide
• Binds to DNA, protein to form adducts
• Loss of cellular control
• Enzyme system
• Glutathione S-transferase
• Neutralizes epoxide

7
Prevention/Avoidance/Detox

• Improve farming/proper food storage
• Harvest ripe crops quickly
• Do not mix animal feed
• Chemical methods
• Ammonia and sodium bisulfite

8
What we still want to know

• Mechanism?
• Latency?
• American lab worker
• Hepatitis vaccination?

9
Peanut Allergy?

• Peanut allergy is nearly always an allergy to
  aflatoxin
• Antibiotic use
• Side effect mold allergy
• Diamond Pet Food Company