Podcast
Questions and Answers
Mycotoxins are exclusively produced by plants.
Mycotoxins are exclusively produced by plants.
False
There are approximately 300-400 recognized mycotoxins.
There are approximately 300-400 recognized mycotoxins.
True
Airborne transmission is one of the modes of spore transmission for mycotoxins.
Airborne transmission is one of the modes of spore transmission for mycotoxins.
True
Mycotoxic effects can be completely eliminated by cooking or canning food.
Mycotoxic effects can be completely eliminated by cooking or canning food.
Signup and view all the answers
A relative humidity level exceeding 70% can promote fungal growth.
A relative humidity level exceeding 70% can promote fungal growth.
Signup and view all the answers
The optimal water activity for mycotoxin production is 0.95.
The optimal water activity for mycotoxin production is 0.95.
Signup and view all the answers
Mycotoxicosis can result from both food ingestion and airborne contamination.
Mycotoxicosis can result from both food ingestion and airborne contamination.
Signup and view all the answers
Mycotoxins are selectively toxic to certain types of plants only.
Mycotoxins are selectively toxic to certain types of plants only.
Signup and view all the answers
Fungal growth and mycotoxin production will occur at a water activity (aw) of 0.93.
Fungal growth and mycotoxin production will occur at a water activity (aw) of 0.93.
Signup and view all the answers
Long-term exposure to mycotoxins poses no health risks to humans.
Long-term exposure to mycotoxins poses no health risks to humans.
Signup and view all the answers
Symptoms of mycotoxicosis can be transmitted from one person to another.
Symptoms of mycotoxicosis can be transmitted from one person to another.
Signup and view all the answers
Aflatoxicosis is a type of toxicity specifically related to aflatoxins.
Aflatoxicosis is a type of toxicity specifically related to aflatoxins.
Signup and view all the answers
Mycotoxins can cause economic loss in both humans and animals.
Mycotoxins can cause economic loss in both humans and animals.
Signup and view all the answers
Sick Building Syndrome can be related to living in moldy indoor environments.
Sick Building Syndrome can be related to living in moldy indoor environments.
Signup and view all the answers
Mycotoxins have no significant effect on animal health or production.
Mycotoxins have no significant effect on animal health or production.
Signup and view all the answers
Possible symptoms of mycotoxin exposure in humans include cold/flu-like symptoms.
Possible symptoms of mycotoxin exposure in humans include cold/flu-like symptoms.
Signup and view all the answers
Study Notes
What are Mycotoxins?
- Mycotoxins are low molecular weight compounds produced by fungi as secondary metabolites.
- They cause toxic effects on animals and humans.
- Over 300-400 compounds are recognized as mycotoxins.
- Only 20 of these compounds are commonly found in food and feed at levels that pose a food safety concern.
Why do Fungi Produce Mycotoxins?
- Fungi produce mycotoxins to destroy their microbial competitors.
Mycotoxin Health Risks
- Mycotoxins are associated with human disease (Mycotoxicosis)
- Mycotoxicosis can cause acute and chronic effects.
- Ingestion of contaminated foods is the primary source of exposure.
- Airborne contamination is also a problem.
Characteristics of Mycotoxins
- The presence of mycotoxins may not be visually apparent.
- Mycotoxins can remain in the organism after the fungus has been removed.
- Mycotoxins are not selective in their targets and can cross plant species barriers.
- Mycotoxins can be heat stable and not destroyed by processes like canning.
Mycotoxins: Mechanisms of Toxicity
-
Cytotoxic:
- Bind to DNA and RNA
- Alter protein synthesis and functions
- Cause oxidative stress (e.g., lipid peroxidation)
- Deplete antioxidants
- Alter cell membrane function and transport
- Potent mitochondrial toxins (numerous mechanisms)
Modes of Spore Transmission
- Airborne: Wind or indoor ventilation systems
- Attached to Insects or Birds: Spreading from plant to plant, animal to animal
- Transportation Mechanisms: Trucks, crop machinery
Fungal Infection
- Fungal infection can occur at any stage of crop production:
- In the field
- During harvesting
- While in silage and storage
- Spores can remain dormant for months or years until favorable conditions arise for germination.
Conditions for Fungal Growth and Mycotoxins Production
- High Temperatures: Over 30ºC for a few days to a week.
- Plant Stress: Drought, flood, or insect invasion.
- High Relative Humidity: Over 70%.
- High Moisture Content: 20% or higher in crops.
Water Activity (aw) and Fungal Growth
- Optimal aw for mycotoxin production is 0.98.
- Reducing aw to 0.95 can reduce both fungal growth and mycotoxin production.
- Aw of 0.93 significantly reduces fungal growth and mycotoxin production.
Mycotoxin Health Hazards
- Generally, the risk is lower in well-developed countries due to improved standards of living.
- High intake of contaminated products, especially in conjunction with limited food sources, can pose a significant risk.
- Long-term exposure to mycotoxins through contaminated food or animal products is the biggest concern.
Symptoms of Mycotoxicosis
- Symptoms often resemble cold/flu-like illness, including fatigue, diarrhea, sore throat, headaches, nosebleeds, and immune suppression.
- Drugs and antibiotics are ineffective in treating mycotoxicosis.
- The symptoms can be traced to contaminated foodstuffs or feed.
- Symptoms are not transmissible from person to person.
- The toxicity is influenced by age, with more severe effects in young and elderly individuals.
Mycotoxin Effects on Humans
- Economic Loss: Impaired health of livestock and animal mortality.
-
Illness:
- Cold/flu-like symptoms
- Fatigue
- Diarrhea
- Sore throat
- Dermatitis
- Headaches
- Nosebleeds
- Immune suppression
Human Health Effects of Mycotoxin Exposure
- Aflatoxicosis (aflatoxin):
- Aplastic Anemia (bone marrow failure) and Bleeding (trichothecenes):
- Acute Pulmonary Hemorrhage:
- Cancer (aflatoxins):
- Birth Defects:
-
Sick Building Syndrome:
- Living in moldy indoor environments can cause itchy eyes, nausea, fatigue, headaches, increased respiratory tract infections, difficulty concentrating.
Chronic Exposure to Mycotoxins
- Cancer induction:
- Kidney toxicity (nephrotoxicity):
- Immune suppression:
- Autism:
- Neurotoxicity:
- Depression:
Mycotoxins, Producing Fungi, Contaminated Food, and Toxicity
| Mycotoxin | Producing Fungi | Contaminated Food | Toxicity |
|---|---|---|---|
| Aflatoxins | Aspergillus flavus, A. parasiticus | Grains, nuts, peanuts | Liver cancer, immune suppression |
| Ochratoxins | Aspergillus ochraceus, Penicillium verrucosum | Grains, coffee, grapes | Kidney damage, immune suppression |
| T-2 Toxin | Fusarium sporotrichioides, F. langsethiae | Grains | Immune suppression, gastrointestinal problems |
| Vomitoxin (Deoxynivalenol) | Fusarium graminearum, F. culmorum | Grains | Vomiting, feed refusal, immune suppression |
| Zearalenone | Fusarium graminearum, F. culmorum | Grains | Estrogenic effects, reproductive problems |
| Fumonisin | Fusarium verticillioides, F. proliferatum | Corn | Liver cancer, neurotoxicity |
Mycotoxin Effects on Animals
- Feed Refusal:
- Impaired Animal Health: Reduced egg production, milk yield, weight gain.
- Metabolites in Food Products: Mycotoxin metabolites can be passed through milk in cheese, dry milk, and yogurt.
- Disease: Inflammation of the sensitive layers of tissue inside the animal's hooves.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Related Documents
Description
This quiz delves into the world of mycotoxins, which are toxic compounds produced by fungi that can pose significant health risks to humans and animals. Learn about the characteristics, sources, and health implications associated with mycotoxin exposure, including mycotoxicosis. Test your knowledge on this crucial food safety topic.
