Aflatoxin Country Assessment for Tanzania Abt Associates, Inc. December 3, 2012

Aflatoxin Country Assessment for Tanzania

Abt Associates, Inc.

December 3, 2012

Abt Associates | pg 2

Objectives of the Country Assessment in Tanzania

To characterize the risks and economic impacts of aflatoxin contamination…

…and to identify promising opportunities for control.


A Conceptual Framework for Aflatoxin Country Assessment

Identify Key Crops of Concern

High Production High Consumption High Value

Step

1

Determine Prevalence of Aflatoxin

Geographical area of Concern Percent Contamination Degree of Contamination

Step

2

Characterize Risks of Aflatoxin Contamination and Exposure

Uses of Crop Risks along Value Chain

Step

3

Estimate Economic Impacts

Agriculture and Food Security Trade

Step

4 Health

Identify Opportunities for Aflatoxin Control

Institutional, Legal and Regulatory Review Control Strategies in Agriculture Trade and Health

Step 5


Data Sources Tanzania 2008-2009 General Household Panel Survey part of the

World Bank’s Living Standards Measurement Study Integrated Surveys on Agriculture (LSMS-ISA) project that has nationally and zonally representative data on household consumption, anthropometry, agricultural production and sales, use of inputs and extension services, and constraints to agricultural production.

Field Research in three locations from different agro-ecological zones – Njombe, Irenga; Bukombe, Shinyanga; Kongwa, Dodoma

Interviews with Ministries and stakeholders in Dar es Salaam, interviews in three rural areas

Secondary Data

– Published and unpublished articles


Key Crops of Concern Maize is the most important agricultural crop in Tanzania in terms of

quantity and value of production, followed by cassava

Groundnuts are important because of its promotion in weaning foods

Milk and cassava are two other potential commodities that could be assessed with additional funding.

Data Source: CountrySTAT, Year, 2010

Step1


Aflatoxin PrevalenceStep2

Zone NB1 Total

Share >LOD1 Mean if detected (ppb) Share >LOD2 Mean if detected

(ppb)Maize

Eastern 40 58% 37.26 68% 46.33North 65 15% 11.03 34% 11.77South 40 3% 1.00 23% 1.84Southern Highlands 99 12% 4.74 38% 4.30West 30 70% 16.51 90% 31.71National 274 24% 20.48 45% 24.30

GroundnutsNorth 20 30% 14.42 100% 7.69South 40 33% 11.80 88% 9.74West 40 35% 10.72 98% 7.50National 100 33% 11.82 94% 8.30

LOD = Limit of Detection; ppb = Parts per Billion


Prevalence of Aflatoxin B1 in Groundnuts


Prevalence of Aflatoxin B1 in Maize


Characterization of Risks Whether the risks of aflatoxin-contamination are

greater on a country’s agriculture and food security, trade and/or health is determined by:

– (1) the uses of aflatoxin-contaminated crop (whether primarily for domestic human consumption, international trade, or feed use);

– (2) levels of awareness about aflatoxins and aflatoxin control among farmers, traders, and consumers;

– (3) the application of tolerances within the food marketing system and types of actions taken by regulators and buyers to mitigate the risk.

Step3


Uses of Maize and Groundnut

Production

Own Consumption Sale to Market

Market Loss Discarded grain Reduced prices Litigation

Human Health Impact Disease burden Reduced productivity

Market Loss Reduced milk productivity Livestock disease burden Reduced prices of products Discarded products.

Contaminated Livestock Products

Livestock Feed

Contaminated Products

Majority of the maize crop in Tanzania is used for direct human consumption (FAOSTAT 2009).

– 68 % -human consumption, – 19 % feed, – 12 % other residual uses, – 2% re-planting

Average agricultural households report selling 17 % of their maize produce, 2 % for feed, using 1 % for seed, and the residual 77 % for own consumption or storage (LSMS-ISA, 2008/9).

Of the 270 MT of groundnut production, 51 % was used directly as food, and 38 %was used for other purposes (FAOSTAT 2009).


Characterization of Risks along the Value Chain

•Are Good Agricultural Practices known and used?

•What is the awareness level of farmers?

Agriculture

•Are there regulations on aflatoxins for commerce?

•Are the regulations enforced?

•Are traders aware about aflatoxins?

Trade• Are the consumers

aware about aflatoxins?

• Do feeding practices contribute to health risks?

Health

ForktoFarm


Agriculture –Risk of Contamination

Analysis of nationally representative data (LSMS/ISA) suggests that the use of Good Agricultural Practices (GAP), which improve plant health and prevent aflatoxin contamination is low

– PESTICIDE USE: 11% for maize and 3% for groundnuts

– IMPROVED SEEDS: 18% for maize and 3% for groundnuts

– FERTILIZER USE: 17% for maize and 1% for groundnuts.

– IRRIGATION: Only 2% of cultivated area under maize is irrigated, negligible for groundnuts

Qualitative field research in three districts suggests that

• Drying of crops is typically done on the ground

• Storage units are rudimentary (No household report using modern structures for groundnuts, 12% use traditional structures, and 78% use sacks/open drums, 1% -4% report using improved structures for maize, 19% use traditional structures and 64% use sacks/open drums.)

• There are few means for moisture measurement and control


Agriculture –Risk of Contamination

Awareness among farmers about the causes and consequences of aflatoxins is low or non-existent.

Agriculture extension systems do not have a set agenda for aflatoxin messaging.

Use of extension systems is low (only 19% of the households report using government extension system).

Farmers do some basic sorting and drying to gain price premium for better sorted grain.

There is an opportunity in Directorate of Food Security, and the planned expansion of extension agents by 11,000.


Trade –Risk of Contamination in Market

Tanzania Bureau of Standards has set standards for maximum aflatoxin (and mycotoxin) concentrations in food products, Tanzania Food and Drugs Authority enforces these standards – but it is effective only for packaged goods and export-bound products

Field research and interviews with stakeholders suggest that there is no testing for aflatoxins in the domestic market.

Awareness about aflatoxins is low among sellers (and buyers).

Interviews with maize millers in Njombe indicated that if farmers bring poorly sorted maize it goes through further sorting at farmer’s cost, but without any specific attention to achieving aflatoxin standards.

Since there is no mandate for withdrawal and destruction of contaminated commodities, grain deliveries rejected by large commercial operations will likely be sold by a trader to smaller feed manufacturers that do not test for aflatoxin.Overall, it appears that aflatoxin-contaminated products could enter the domestic

market without any cost to the producers, traders and retailers.


Health –Risk of Aflatoxin Exposure

Consumers’ level of aflatoxin knowledge is very low in Tanzania and exacerbated by the large share of maize in household diets.

There is heavy reliance on maize-based porridges during a child’s weaning stage.

A large share of maize consumption comes from own production for agricultural households (63 %).

Share of Foods in Weekly Calorie Intake of Households


Key Risk and Expected Impact of Aflatoxin Contamination in Nigeria

Greatest risk and impact on:

Health

Low awareness among farmers,

traders and consumers.

Majority of maize and groundnuts is

consumed domestically

Low enforcement of existing regulations on aflatoxins/mycotoxins


Economic Impact-Agriculture and Food Security

There is negligible to no aflatoxin control by farmers, yet absence of price premium for aflatoxin-free maize implies that there are no actual market losses to producers or traders of primary commodities destined for direct human consumption.

On the other hand, suppliers of susceptible commodities--maize, groundnuts-used for export market in poultry or fish feed may suffer absolute or partial rejections as well as price penalties.

Step4


Economic Impact-Agriculture and Food Security (continued)

All four pillars of food security are affected but not perceived

• Availability -- Aflatoxin-free maize and groundnuts is impacted by this challenge but not recognized by consumers or food markets.

• Access – Farmers generally do not yet incur loss in farm revenue because of aflatoxin-contamination in their grain. Use of aflatoxin control will imply increased production costs, that may be tempered by premiums on aflatoxin-free crop

• Utilization – The largest impact of contamination is on human consumption of unsafe and possibly less nutritious products that arises due to lack of aflatoxin control and lack of awareness

• Stability – Since aflatoxins are dependent on climactic conditions, stability in the other three pillars will vary with prevalence

Step4


Food Security : Availability and Access

Step4

Exhibit 6 2: Percentage Contribution of Groundnut and Maize on Food Availability and Access for ‑Agricultural Households

Food Availability (Percentage from Own Production)

Food Access (Percentage Contribution to Agricultural

Income)

Zone Maize Groundnuts Maize Groundnuts

Central 73% 77% 9% 10%

Eastern 44% 30% 2% 14%

Lake 61% 79% 2% 6%

North 42% 18% 0% 17%

South 82% 80% 7% 13%

Southern Highlands 71% 67% 3% 19%

West 61% 75% 5% 6%

Zanzibar 1% 12% 12% 8%

National 63% 72% 9% 10%

Source: Estimated from LSMS-ISA (2008/9)


Food Security: UtilizationStep4

Exhibit 6 1: Calorie Intake Share of Foods by Key Zones in Tanzania‑

Zone Cashew Cassava Groundnut Maize

Milk and milk

productsRice

All Other Crops

Central 0% 1% 8% 43% 1% 5% 41%Eastern 0% 6% 1% 31% 1% 20% 41%Lake 0% 14% 3% 32% 2% 7% 43%North 0% 4% 1% 46% 4% 8% 37%South 1% 26% 3% 35% 0% 9% 27%Southern Highlands 0% 6% 3% 55% 1% 6% 28%

West 0% 9% 5% 51% 1% 11% 23%Zanzibar 0% 9% 1% 8% 1% 37% 45%National 0% 9% 3% 41% 2% 10% 34%Source: Estimated from LSMS-ISA (2008/9)


Utilization: Calorie Intake by zones.

Zone Cashew Cassava Groundnut Maize

Milk and milk

productsRice

All Other Crops

Central 0% 1% 8% 43% 1% 5% 41%

Eastern 0% 6% 1% 31% 1% 20% 41%

Lake 0% 14% 3% 32% 2% 7% 43%

North 0% 4% 1% 46% 4% 8% 37%

South 1% 26% 3% 35% 0% 9% 27%Southern Highlands 0% 6% 3% 55% 1% 6% 28%

West 0% 9% 5% 51% 1% 11% 23%

Zanzibar 0% 9% 1% 8% 1% 37% 45%

National 0% 9% 3% 41% 2% 10% 34%

Source: Estimated from LSMS-ISA (2008/9)


Trade Impact Domestic Trade

– Farmers incur some cost for basic sorting to respond to this price differentiation.

– Some degree of price differentiation for quality exists and farmers face loss for additional cost of sorting required by millers.

– However, the differentiation is not because of aflatoxin or mycotoxins

– Our field research found no domestic testing and awareness of aflatoxins/mycotoxins for direct human consumption

Therefore, given the current conditions, there is negligible, if any, domestic market impact of aflatoxin contamination.


Trade Impact in Groundnuts

Historically the export share was as high as 27 percent, but has now settled to between 2-6 percent.

There were no aflatoxin related alerts in EU alerts and rejection system in the last 5 years.

EU harmonization of aflatoxin standards was in 1998.

An ICRISAT study notes that the key constraints to groundnut production unfavorable weather, management skills, access to credit, pests, diseases, access to inputs, management.

Tanzania can gain from investing in improving groundnut production to compete in the international trade market. However, aflatoxins are not the only reason Tanzania has not entered this market so far.

19611964

19671970

19731976

19791982

19851988

19911994

19972000

20032006

20090

50,000

100,000

150,000

200,000

250,000

300,000

0.0%

5.0%

10.0%

15.0%

20.0%

25.0%

30.0%

35.0%

Groundnut Production (Tonnes)Share in World Export (%)Export Share in Production

Tonn

es


Trade Impact in Maize

Historically maize exports have been low. Maize exports have often been banned--as they are now--

because of this crop’s importance for food security.

Constraints other than aflatoxin contamination is limiting export of maize from Tanzania.

19611963

19651967

19691971

19731975

19771979

19811983

19851987

19891991

19931995

19971999

20012003

20052007

20090%

1%

2%

3%

4%

5%

6%

7%

0

500,000

1,000,000

1,500,000

2,000,000

2,500,000

3,000,000

3,500,000

4,000,000

4,500,000

5,000,000

Maize Production (Tonnes) Export Share in Production


Health Impact Arguably the largest are of impact of aflatoxin

contamination in Tanzania.

Conclusive evidence of health impact of aflatoxin is established for liver cancer – this is quantified and monetized in the country assessment for a range of aflatoxin prevalence values.

Impact on stunting is still inconclusive, with only one article establishing the relationship between aflatoxin contamination and stunting


Estimating Health Impact

Aflatoxin Contamination

(ng/g)

Consumption(gram/day)

Body Weight(kg)

Exposure to Aflatoxins

(ng/kg-bw/day)

Shares of HBV

positive population

Liver Cancer Cases

(number/year)

Exposure to Aflatoxins

(ng/kg-bw/day)

Population(2010

projected) Share of HBV

positive population

Cancer Potency for HBV Positive

(0.3 per 100,000)

Cancer Potency for HBV Negative

(0.01 per 100,000)

Sum of:

Population Risk (Cancers/year/

100,000


Consumption of Maize


Consumption of Groundnuts


Sensitivity Analysis of ImpactsEstimated the impact with varying contamination.Even at 10 ppb the current consumption levels of maize implies that 1092 out of 1209 liver cancer cases can be attributed to aflatoxins.

In another sensitivity analysis, we estimate that if HBV prevalence is reduced to zero, the total number of liver cancer cases attributed to aflatoxins would reduce 3-fold

Zone

Maize and GroundnutConsumption (g/person(60kg)/day)

Aflatoxin Contamination (ppb)1 4 10 20 50 100

Central 367 9 36 90 181 452 903

Eastern 261 11 46 115 230 575 1,150

Lake 278 15 60 149 298 746 1,491

North 362 17 68 171 342 854 1,708

South 299 8 32 81 162 406 812

Southern Highlands

495 20 81 203 406 1,015 2,030

West 508 28 111 277 554 1,385 2,770

Zanzibar 66 1 2 6 11 28 55

National 521 109 437 1,092 2,184 5,460 10,920


Opportunities for Aflatoxin Control in Africa

Institutional, Policy and Regulatory Environment Setting and publicizing clear division of roles and responsibilities may

yield greater regulatory efficiencies.

Leverage existing opportunities in newly formed strategies (e.g. agriculture, nutrition) and develop guidance that incorporates mycotoxins.

Each agency should also agree on a coordinated, risk-based surveillance strategy to communicate and isolate threats to the food system.

Changing the mandates of TBS, TFDA, and other specialized agencies to regulate raw commodities destined for domestic consumption.

Set procedures for withdrawal of contaminated samples and explore alternative uses for contaminated products.

Strengthen the institutional mandate for cross-ministerial collaboration in shifting production and consumer demand for food quality.

Step5



Scale public and private sector initiatives to increase access to and adoption of aflatoxin-reducing agricultural inputs and practices, e.g. scaling up targeted input voucher programs for the poorest farmers.

Capitalize on mobile technologies and banking services to design business models for agricultural inputs that serve the poor.

Use bio-controls such as the IITA-developed Aflasafe approach or natural fungicides to reduce aflatoxin levels in soil and among treated crops, even after poor storage.

Introduce simple yet effective post-harvest techniques such as drying above ground or using economical solar driers to reduce adverse conditions that favor growth

Introduce improved storage methods and materials such as hermetic storage toarrest development of the responsible Aspergillus species

Use national data on agricultural stressors to target market-based solutions to address localized threats.

Use the global research agenda on aflatoxin to inform and complement domestic research, and vice versa

Agriculture



Raise awareness of tolerances and associated SPS practices in foreign markets of interest, and improve the capacity of grower/shippers and exporters to assure compliance

Spearhead harmonized SPS policies within East Africa that tend to reduce the mycotoxin problem (both aflatoxins and fumonisins) while facilitating cross border trade

Explore alternative uses for contaminated crops that make sense for Tanzania, and adjust official standards accordingly

Use economic incentives to shift behaviors in the supply chain while simultaneously expanding access by farmers to the best aflatoxin control solutions

Encourage the use of improved storage systems at all levels that reduce deterioration and loss, coupled with warehouse receipts programs that facilitate usage of commercial or community-managed storage as well as actions by the commodities exchange board and marketing boards (if revived) to preserve the quality, condition, and safety of agrifood products destined for human consumption

Leverage the formation of marketing boards for Cereals and other products that includes maize and groundnuts.

Trade



Encourage dietary diversity based on non-susceptible plant and animal products

Carry out joint campaigns between the Ministries of Health and Agriculture to raise consumer demand for good agricultural practices that lead to safer food

Improve awareness of human nutritional requirements, especially for pregnant and lactating women and during the first 1,000 days of life

Foster changes in household feeding/weaning and food use/preparation practices through behavioral change communications

Upgrade the food safety control system. particularly as it affects human health/welfare. i.e. policies and standards for mycotoxins/aflatoxins that take into account average daily intake, surveillance and testing methods, withdrawal/compensation procedures, penalties for infringements

Stay current on global research on the linkages between aflatoxins and health/nutrition while exploring avenues for further research of particular relevance to Nigeria

Pursue universal access to the HBV vaccine.

Health


Conclusion Aflatoxins are carcinogens w/other health effects

Contamination can interfere with trade & commerce

Believed to impact all of Africa, including Tanzania

Cost of inaction is high, especially in human health

Range of solutions is broad, but resources scarce

Prioritization and customization is needed

Mitigation should be multi-sectoral and coordinated

Documents

Aflatoxin Country Assessment for Tanzania Abt Associates, Inc. December 3, 2012