Aflatoxin poisoning : Aflatoxicosis Aflatoxin poisoning Aflatoxin Mycotoxins : Aflatoxin is a type of mycotoxin produced by Aspergillus molds the most notable ones being Aspergillus flavus and Aspergillus parasiticus. Aflatoxin Mycotoxins Slide 3: Aflatoxin is probably the most well known mycotoxin, This is because aflatoxins are very toxic and highly carcinogenic. Slide 4: The technical term for poisoning by aflatoxin mycotoxins is aflatoxicosis.
This usually occurs from eating food contaminated with aflatoxin mycotoxins.
It affects man and animals (live stock) Slide 5: Aflatoxicosis is not contagious and drugs and antibiotics do little to help. Aflatoxicosis damages the liver more than any other organ. : Aflatoxicosis damages the liver more than any other organ. Aflatoxin Types : There are three main types of aflatoxin mycotoxins:
Aflatoxins B: This group includes aflatoxin B1 and B2. Aflatoxin B1 is the most common aflatoxin, as well as the most toxic and carcinogenic.
Aflatoxins G: This group includes aflatoxin G1 and aflatoxin G2
Aflatoxins M: This group includes aflatoxins M1 and M2. These aflatoxins are metabolic products which are found in the urine and milk produced by animals which have been given feed with aflatoxins in it. Aflatoxin Types habitat : The native habitat of Aspergillus is in soil,
hay, and grains undergoing microbiological deterioration, and
it invades all types of organic substrates whenever conditions are favorable for its growth. habitat Contamination conditions : Aflatoxin-producing members of Aspergillus are common and widespread in nature.
They can colonize and contaminate grain before harvest or during storage.
Favorable conditions include high moisture content (at least 7%) and high temperature.
The toxin can also be found in the milk of animals that are fed contaminated feed. Contamination conditions Slide 12: The condition is most common in poorly developed countries where there are insufficient controls on the presence of aflatoxin in food. Peanuts:- : Peanuts:- Slide 14: In food Slide 15: Any grain with levels exceeding 1000 ppb should be destroyed and not be salvaged by blending with grain of lower concentrations. Exposure Route : For Aflatoxin exposure
Inhalation, eye, skin, ingestion (most common ) Exposure Route Aflatoxin Symptoms : How badly a person is affected by aflatoxin mycotoxins depends on things like the person's age,
level of exposure,
duration of exposure,
health, strength of their immune system,
diet and environmental factors.There are two main ways people are usually exposed to aflatoxins: Aflatoxin Symptoms Acute Toxicity : Acute toxicity is caused when large doses of aflatoxin are ingested. This is common in livestock.
The principal target organ for aflatoxins is the liver.
After the invasion of aflatoxins into the liver, lipids infiltrate hepatocytes and leads to necrosis or liver cell death.
This is mainly because aflatoxin metabolites react negatively with different cell proteins,
which leads to inhibition of carbohydrate and lipid metabolism and protein synthesis. Acute Toxicity Slide 19: In correlation with the decrease in liver function,
there is a derangement of the blood clotting mechanism, icterus (jaundice),
and a decrease in essential serum proteins synthesized by the liver.
Other general signs of Aflatoxicosis are edema of the lower extremities, abdominal pain, and vomiting.
Convulsions, Mentalimpairment,Hemorrhaging Coma ,Death chronic exposure(toxicity) : taking in small amounts of aflatoxins at a time, but over a long period(chronic exposure).
This might happen if a person's diet has a small amount of aflatoxins, for example. When this happens it can cause:
Growth and development impairment (in children).
Liver cancer due to DNA mutation caused by aflatoxins chronic exposure(toxicity) About some of the effects of aflatoxicosis : 1-immuno suppression.
Immuno-suppression is due to the reactivity of aflatoxins with T-cells, decrease in Vitamin K activities, and a decrease in phagocytic activity in macrophages.
These immuno suppressive effects of aflatoxins predispose the animals to many secondary infections due to other fungi, bacteria and viruses. About some of the effects of aflatoxicosis Slide 22: 2- mutagenesis and cancer:-
aflatoxin metabolite can intercalate into DNA and alkylate the bases through its epoxide moiety.
This is thought to cause mutations in the p53 gene, an important gene in preventing cell cycle progression when there are DNA mutations, or signaling apoptosis. Slide 23: These mutations seem to affect some base pair locations more than others — for example, the third base of codon 249 of the p53 gene appears to be more susceptible to aflatoxin-mediated mutations than nearby bases. Slide 24: Onset of Symptoms
Relatively slow (>8 h after exposure)
Rapid diagnostic assay : None available. Slide 25: Antidote
In cases of ingestion, feeding large quantities of an adsorbent such as activated charcoal may be used.
Antioxidants such as ellagic acid and inducers of some cytochromes P450, such as indole-3-carbinol, may give a protective effect.
There is no treatment for aflatoxin poisoning. There are only prevention methods. Slide 26: Supportive Care
Monitoring of liver function, dialysis or blood transfusions, treatment of symptoms.
Aflatoxins are inactivated by a wide range of reagents.
Concentrated ammonia and sodium bisulfite have been the focus of study because they can be used on foodstuffs with affecting their organoleptic properties. outbreak of aflatoxicosis : in Kenya outbreak of aflatoxicosis has resulted in 125 recognized deaths(2004).
one of The largest reported outbreak of aflatoxicosis to date occurred in western India in 1974, resulting in 397 recognized cases and 106 deaths.
http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5334a4.htm outbreak of aflatoxicosis In sudan : In sudan حملة إرشادية لمكافحة(الأفلاتوكسين) 18/12/2011 : الخرطوم:الصحافة: تبدأ اليوم الحملة الارشادية لمكافحة السموم الفطرية في الأغذية تحت شعار « معاً نحو غذاء صحي وآمن « بولاية الخرطوم. وقال المدير العام للهيئة السودانية للمواصفات والمقاييس الفريق عبدالله حسن عيسى إن الحملة تستهدف المنتج ، والمصنّع ، والمستهلك ، مؤمناً على أهمية وإستمرارية الحملات لدورها الكبير وأثرها الفعال في تصحيح الممارسات الخاطئة والتوعية والتبصير بالممارسات الصحيحة لتخفيض نسبة الإصابة بالسموم الفطرية ، مشيراً لأهمية الحملة في توعية المستهلك بمخاطر السموم الفطرية (الأفلاتوكسين) وكيفية تفادي أخطارها وتهديدها للصحة العامة .من ناحيتها، اكدت مديرة المركز السوداني للسموم الفطرية، إبتهاج بر التوم، أن برنامج الحملة يشتمل على زيارات ميدانية إرشادية للمصانع والمخازن بولاية الخرطوم، بجانب لقاءات مباشرة مع المنتجين والمصنعين للفول السوداني (الدكوة). حملة إرشادية لمكافحة(الأفلاتوكسين) 18/12/2011 Thank you for listening : Wahj mohamed khair Thank you for listening The end : The end