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Agriculture & Food Security
Dimensions of Aflatoxins
Ranajit Bandyopadhyay, IITA, Ibadan, Nigeria
IFPRI/IITA/TNVASU GROUP DISCUSSION, TNAU, CHENNAI, INDIA, 14 JUNE 2013
www.iita.org
Where we are
Our R4D activities reach
approximately 85% of
national systems in Africa
and beyond.
www.iita.org
We work with partners in Africa
and beyond to reduce producer
and consumer risks, enhance
crop quality and productivity, and
generate wealth from agriculture.
What we do
Who we are
Our research for development activities
have delivered over 70% of the CGIAR's
positive impact on the food security and
livelihoods of over 500 million people in
sub-Saharan Africa and beyond.
www.iita.org
• Highly toxic metabolite produced by the ubiquitous Aspergillus flavus fungus
• The fungus resides in soil and crop debris, infects crops and produces the toxin in the field and in stores
Aflatoxin Facts
• Contamination possible without visible signs of the fungus
• Fungus carried from field to store
www.iita.org
Aflatoxin Problem Starts in the Field
0
20
40
60
80
100
120
140
160
1 2 3 4 5 6 7 8 9 10 11 12 13 14
Farmers
Afl
ato
xin
(p
pb
)
792 309
2010: Maize
64% fields above 20 ppb at harvest in northern Nigeria
Increases in stores; interventions required in field and stores
acute
acute hepatic necrosis, cirrhosis,
carcinoma
Death; 108 in 1974 in Gujarat, 250
to 15,000 ppb aflatoxins in corn
chronic
carcinogenic
anti-nutritional
immune-suppressive
gut integrity?
BBC 2004, Gong et al 2004, NIEHS 2010
underreported
unknown
Human Health Effects
Kenya
district samples total aflatoxin levels (ppb)
<20 21-99 100-1,000 >1,000
Makueni 91 35 13 40 12
Kitui 73 38 21 32 10
Machakos 102 49 25 23 3
Thika 76 66 17 13 4
Total 342 47% 19% 27% 7%
CDC and Kenyan Ministry of Health 2004
Total samples % samples with aflatoxin levels (ppb)
<5 5-15 16-30 >30
2074 53% 6% 15% 26%
Bhat et al. 1997; Food Add. & Cont.
India
Aflatoxins in Markets
www.iita.org
Aflatoxin and Poultry (Broilers)
Aflatoxin
levels in
feeds in
Nigeria
Aflatoxin level (ppb) Samples (%)
<20 (safe) 38
>20 to 100 (up to 5x) 14
>100 to 500 (up to 25x) 41
>500 to 1,000 (up to 100x) 7
AF-free diet 500 ppb AF diet
AF-free
diet
500 ppb AF diet
~40% reduction in
live weight (8 weeks)
Aflatoxin
Intervention
Medical
Agriculture
Surveillance
Enterosorption
Pre-harvest
Food processing
e.g. Novasil clay
Agriculture & Medical Prevention of Aflatoxin-
related Food Security and Health Effects
(Adapted from Wild and Hall, Mutation Res., 2000)
Awareness
Regulation
Provision of safe food
Early diagnosis
Post-harvest
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AF36
Aflaguard
Biocontrol WORKS
In 100’S of thousands of acres in
the US!
IT WORKS In Africa
TOO!
Aflasafe
Strong Partnership
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• IITA • USDA • AATF • BMGF • Doreo Partners • National institutions
www.iita.org A member of CGIAR consortium
Biocontrol
Mycored Europe, 28 May, 2013
In nature, some strains produce a lot
(toxigenic), and others no aflatoxin
(atoxigenic)
Atoxigenic strains are already present on
the crop
Increase the frequency of atoxigenic
strains & shift population profile
Thus, aflatoxin contamination reduced
Atoxigenic strains can be applied without
increasing infection and without
increasing the overall quantity of A.
flavus on the crop or in the environment
Strains move from field to stores
Multiple year & crop carry-over effect
We use only native strains
0
25
50
75
100
Natural Biocontrol
Incid
en
ce (
%)
T
O
X
I
G
E
N
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C
A
T
O
X
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G
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N
I
C
How Does aflasafe Work?
Broadcast @ 10 kg/ha 2-3 weeks before flowering
Sporulation on moist soil
Spores
Insects
Aflasafe in 5 kg boxes
3-20 days
Wind
Soil colonization
30-33 grains m-2
Fungal network in killed grain
www.iita.org A member of CGIAR consortium Mycored Europe, 28 May, 2013
Atoxigenic Strain Identification
Collection/characterization Toxin assay
Field
efficacy
test
Lab
competition
assay
VCG/DNA characterization
cnx nia-D
Unknown 2
+
www.iita.org A member of CGIAR consortium
Strain Selection Criteria
Mycored Europe, 28 May, 2013
In the laboratory (~5,000 strains):
• Does not produce aflatoxin
• VCG/SSR group with
• Wide geographic distribution
• No toxigenic member
• Defective in >2 aflatoxin & CPA
genes
• Outcompetes toxigenic strains After field application:
• Superior capacity to colonize,
multiply and survive in soil
• Superior frequency of isolation
from grains
• Superior capacity to reduce
aflatoxin 8-12 native strains
selected for field tests
4 native strains
formulated into
the final
product
www.iita.org
Farmers treating maize and groundnut fields with Aflasafe in Nigeria
MAIZE: Aflatoxin reduction (%)
Stage 2009 2010 2011 2012
Harvest 82 94 83 93
Storage 92 93 x x
PEANUT: Aflatoxin reduction (%)
Stage 2009 2010 2011
Harvest - 95 82
Storage 100 80 x
Results from 482
on-farm trials
71% and 52% carry-over of
inoculum 1 & 2 years after
application
75
94 100
0 3
39
73
27
100
80
60
40
20
0
<4 <10 <20 >20
EU WFP US unsafe
maximum allowable aflatoxin level (ppb)
farm
ers'
fie
lds
(%)
Aflasafe
untreated
Productivity increased of communities in
aflasafe-treated areas
DALYs saved: 103,000 - 184,000 cost-effectiveness ratio: 5.1 - 24.8
Source: Felicia Wu, Pittsburgh Univ.
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Impact of Aflasafe on Trade and Health
Plots
Observed
aflatoxin
Apparent
reduction
Applied
VCGs
in Control
Aflatoxin if
Applied VCGs
not Present
Actual
Reduction
Treated 17 ppb
64% 88%
Control 49 ppb 66% 143 ppb
Data Measured Calculated Measured Calculated Calculated
www.iita.org A member of CGIAR consortium
KENYA: On-Station Trials
Mycored Europe, 28 May, 2013
Substrate and time of sampling Katumani Kiboko
Soil before application 70 44
Maize grain at harvest 5 0
Incidence (%) of S strain and Aspergillus parasiticus in soil before
treatment and on the crop at harvest, Katumani
Apparent Versus Actual Reductions in Aflatoxin, Bura
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Farmers treating groundnut fields
Aflatoxin Reduction:
2010 : 87% at harvest; 89% after Storage
2011: 82% at harvest; 93% after Storage
38 Farms Treated in 2010
40 Farms Treated in 2011
196 Farms Treated in 2012
Senegal: aflasafe SN01
www.iita.org A member of CGIAR consortium Mycored Europe, 28 May, 2013
www.iita.org A member of CGIAR consortium
Product Types
Mycored Europe, 28 May, 2013
National
Products
Products ready for registration
Products under testing
Strain development in progress
Aflasafe-NigeriaTM
Aflasafe-SenegalTM
Aflasafe-KenyaTM etc…
Aflasafe-WestTM
Aflasafe-EastTM
Aflasafe-SouthTM
Regional
Products Senegal
Mali
Burkina
Ghana
Nigeria
Kenya
Tanzania
Mozambique
Zambia
www.iita.org A member of CGIAR consortium
Aflasafe Production in Lab
Mycored Europe, 28 May, 2013
30 tons produced in 2011 and 2012 for deployment
Policy Statement by the Honourable Minister of Agriculture, Nigeria
Various Nigerian stakeholders have developed a 5 year, 4 step commercialization plan. All parties involved, IITA, Doreo, and the government, have critical roles to play over the next five years to ensure that Aflasafe treated food crops are successfully introduced into the market.
Dr Akin Adesina
www.iita.org A member of CGIAR consortium
Markets for Aflasafe
Mycored Europe, 28 May, 2013
Poultry industry
Export-oriented aggregators
Food processors
Large commercial farmers
Smallholder farmers
Market based
• Poultry feed
• Premium food
market
AgResults (Incentive-
cum-market based)
ma
rke
t d
em
an
d f
or
Afl
as
afe
• 60% maize consumed by farmers
• 40% sold in the market
Maize & Poultry Growth
• Nigerian maize production has grown from 4 million metric tons in 2000 to a 7.3 million metric tons in 2010
• Nigerian poultry production has grown from 113 Million birds in 2000 to 192 million birds in 2010
• Poultry feed is approximately 60% maize.
• >60% of maize has >20 ppb aflatoxin
• Poultry farmers currently paying $3-13 per ton of feed for aflatoxin binders
• Annual demand for maize: 1 million tons
Nigerian Govt Bans Poultry Imports
Index of growth in production for maize and
poultry relative to Nigeria’s production in 1961*
Measure: Relative growth in production
Poultry Industry… Key Driver of Domestic Maize Production
Poultry Feeding Study
$3,200 net
profit from
10,000 birds
in 8 weeks
www.iita.org Mycored Europe, 28 May, 2013 A member of CGIAR consortium Mycored Europe, 28 May, 2013
Aflasafe maize feed Toxic maize feed
www.iita.org A member of CGIAR consortium
Key Economic Drivers
• Ex-factory price: $12.2 including 28% EBITDA
• Farm Gate price: $15.6
• Maize yield required for farmers to recover aflasafe cost + 33% profit: 3.5 t/ha
• Yield enhancement to go hand in with aflasafe use
• Innovation Platform: Poultry farmers to buy all aflasafe maize at a premium
Mycored Europe, 28 May, 2013
Willingness to Pay
www.iita.org Mycored Europe, 28 May, 2013 A member of CGIAR consortium Mycored Europe, 28 May, 2013
100% 99%
83%
60%
25%
19%
34% 31%
18%
12%
5% 4% 0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
$0 $3 - $6 $6 -$9 $9 - $12 $12 - $15 $15 - $19 $20
Farmers who have used Aflasafe (n=246) Farmers who have not used Aflasafe (n=119)
Target Farm Gate Price
Range
• All prior-users willing to pay; almost 50% non-users willing to pay
• Prior-users willing to pay more than non-users Source: G. Okpachu & T. Abdoulaye
www.iita.org A member of CGIAR consortium Date: 28 May, 2013
Aflasafe Plant Plan
Lab
Inoculation, Packaging
& Product Storage
Grain Intake,
Cleaning,
Pasteurisation
and Storage
Capacity 5 tons/hour
Babban Gona Pilot
www.iita.org A member of CGIAR consortium Mycored Europe, 28 May, 2013
• Farmers’ cooperative with professional management
• Credit, inputs and technical services
• Yield enhancing practices
• Aflatoxin awareness
• Aflasafe use
• Aflatoxin testing – 100% met standard
• Incentive for meeting aflatoxin standard
• Warehousing
• Output marketing – linking to market
• Return profit after sale ($140/ha)
• Farmers keep part of the harvest for family use
Summary • Aflatoxins in food and feed pervasive in Africa
• Biological control in conjunction with other management practices can dramatically reduce aflatoxin contamination and improve food safety and security
• Efforts underway to pilot commercialization of aflatoxin biocontrol and develop regional strains
• Technologies available but must be implemented to reduce aflatoxin burden in African economies and food system
• Support and partnership needed from national governments, regulators, donors/investors, private food/feed sector and farmer groups
www.iita.org
Experimental varieties
Aflatoxin reduction (%)
Resistance alone
Biocontrol alone
Resistance + Biocontrol
RSYN2-Y 66 (60) 91 (90) 97 (96)
RSYN3-W 88 (46) 74 (94) 97 (97)
SYN3-Y 68 (66) 91 (95) 97 (98)
TZB-SR (Susc.) 58 (1152) ppb 92 (86)
% Reduction in experimental varieties compared to susceptible variety (TZB-SR) under natural conditions
% Reduction in varieties with biocontrol compared to susceptible variety (TZB-SR) under natural conditions
% Reduction in biocontrol treated plots compared to control plots of the same experimental variety
% Reduction in varieties with biocontrol compared to susceptible variety (TZB-SR) under natural conditions
% Reduction in biocontrol treated plots compared to untreated plots of the same variety
Synergistic Effect of Resistance and
Biocontrol in Reducing Aflatoxins at Harvest and after poor storage
Ibadan IITA
Tucson
USDA/ARS IITA, USDA & Doreo have Teamed up to Bring
Aflatoxin Prevention to Africa
Made Possible by Many National Partners in Ministries, Industry, and on the Farm
Nigeria
For more information about aflatoxin biocontrol for Africa, check out: www.aflasafe.com