Roundtable of aflatoxin experts on “Building a multi-stakeholder approach to mitigate aflatoxin contamination of food and feed” Brussels, Monday 25th January 2016

1. AFLATOXIN IN MILK
E. K. KANG’ETHE, UNIVERSITY OF NAIROBI, KENYA

2. Aflatoxin?
 Are secondary metabolites produced by toxigenic
fungi, mainly Aspergillus flavus and Aspergillus
parasiticus.
 The major metabolites are Aflatoxin B1 and B2.
 These toxins are produced by the fungi in cereals,
pulses and nuts under favorable conditions of
temperature and moisture
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3. Aflatoxins?
 When feed contaminated with aflatoxin B1 are fed to
animals, the Aflatoxin B1 is hydroxylated by ruminal
enzymes to Aflatoxin M1
 Aflatoxin M1 is excreted through the milk. The
translation of AFB1 in feed to AFM1 is about 200:1
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4. SIGNIFICANCE of AFM1
 Contains about 2-10% of the carcinogenic potential
of AFB1. Listed as carcinogen class B by IARC
 Infants are weaned onto milk and if contaminated
with AFM1 exposes infants to AFM1 when not
immunocompetent
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5. SIGNIFICANCE of AFM1
 Affects food safety -
 Prevalence of aflatoxin in milk in Kenya estimated
at 72%. This translates into 3.744 billion litres out of
5.2 billion which are annually are contaminated.
20% is with aflatoxin above 50 ppt (FAO/WHO)=
748 million litres should be discarded annually-
create insufficiency.
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6. SIGNIFICANCE of AFM1
 Used as a non tariff barrier in trading with milk and
milk products. If the destroy 748 Million liters of milk,
cost $249M annually – lost in trade or more to import
 Over 80% of milk production in Africa is by
smallholder farmers. Livestock important livelihood to
help populations move out of poverty. Aflatoxins
drives them deeper back.
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7. AFM1 in African Milk
Cow
milk
Country Sample
size
positive
Level ug/kg Reference
Nigeria 3/22 0.11 -0.52 Atanda et al 2007
Kenya 474/613 0.005b-0.78 Kangethe and Langat 2009
South Africa 42/42 0.04-1.32 Dutton et al 2010
Cameroon 10/63 0.0006-0.527 Tchana et al 2010
Sudan 42/44 0.22 -6.90 Elzupir and Elhusseini 2010
Tanzania 34/37 Urio et al 2006
Cheese Tunisia 11/15 3.5 -11.5 Ghali et al2008
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8. MITIGATIONS
 Is this a problem of intensive dairying?
 Yes, all supplement during milking with commercial
formulations or rotten grains unfit for human consumption
 Are farmers aware of the consequences of feeding possibly
aflatoxin contaminated feed?
 No.
 60% use rotten grains as animal feed.
 55% do not think the milk from animals feed
contaminated maize is a risk.
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9. MITIGATIONS
 Yes
 They associated reduced milk production and quality,
susceptibility to diseases and reduced weight gain with
feeding rotten maize – BUT NOT AFLATOXIN
 WHY are technologies extended not adapted and adopted?
 Illiteracy level is very high –majority are primary school
graduates or no formal education
 Capital and time invested outweighs benefits
 Build practical capacity on good husbandry practices
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10. MITIGATIONS
 Livestock not considered when national food
estimates are calculated – Farm for livestock
 Feed inspection and aflatoxin surveillance should be
incorporated into national surveillance systems
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11. THE ESSENCE OF LIFE
IS TO PLANT A TREE
UNDER WHOSE SHADE
YOU DO NOT EXPECT TO SIT
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