Mycotoxin contamination in Tanzania: Quantifying the problem in maize and cassava

in households and markets

Fen Beed (IITA)

Africa RISING East and Southern Africa Research Review and

Planning Meeting, Arusha, Tanzania, 1-5 October 2012

Mycotoxins - aflatoxin, Health & Trade

• Synergistic with Hepatitis B Virus (HBV) to cause liver cancer• 30 times more potent in HBV+

people• 5-60 times higher cancer risk

• Impairs growth and development of children

• Suppresses immune system • Impedes uptake and utilization of

micronutrients in human systems• Animal productivity reduced –

growth rate, embryo toxicity, feed efficiency, cancer, death……

• Highly toxic metabolite produced by the ubiquitous Aspergillus flavus fungus

• The fungus infects crops and produces the toxin in the field and in stores

• Fungus carried from field to store• Contamination possible without

visible signs of the fungus

• Some predisposing factors: – pre-harvest high temp and

drought stress– wet conditions at harvest

and post-harvest periods

– insect damage

Aflatoxin FactsAflatoxin Facts

Prevalence of Aflatoxins in Food & Feed

• 2.5 billion exposed worldwide

• Several African staple commodities affected

• High human exposure in Africa – mother to baby

• Levels and frequency of occurrence high• >30% maize in stores with >20 ppb aflatoxin

• ~90% stores are contaminated with Afla fungi

• Up to 40% grain in households with aflatoxin

• Concern for food and feed processors, government and emergency food reserve agencies

• Highly toxic strains, conducive environmental conditions, traditional farming methods and improper grain drying and storage practices, unregulated markets

Tanzania Surveys

1> determine prevalence of mycotoxins in maize and cassava

2> questionnaires field, processing, storage methods

3> increase awareness

4 > Link to PACA; collect isolates from maize & groundnut for characterisation of potential biocontrol agents and Abt Associates

MAFSC

TPRI& IITA

SUA

TFDA

Survey teams

Samples milled, sub sampled, and for maize; pre-tested using serological methods for afaltoxin and fumonisin and sent along with all cassava

To IFA-TULLN for LC-MS/MS; state of the art detection capable of quantifying more than 50 toxic metabolites in a single analysis

Sample analyses

Samples milled, sub sampled, and for maize; pre-tested using serological methods for afaltoxin and fumonisin and sent along with all cassava

To IFA-TULLN for LC-MS/MS; state of the art detection capable of quantifying more than 50 toxic metabolites in a single analysis

Sample analyses

Samples milled, sub sampled, and for maize; pre-tested using serological methods for afaltoxin and fumonisin and sent along with all cassava

To IFA-TULLN for LC-MS/MS; state of the art detection capable of quantifying more than 50 toxic metabolites in a single analysis

Sample analyses

Samples milled, sub sampled, and for maize; pre-tested using serological methods for afaltoxin and fumonisin and sent along with all cassava

To IFA-TULLN for LC-MS/MS; state of the art detection capable of quantifying more than 50 toxic metabolites in a single analysis

Sample analyses

Samples milled, sub sampled, and for maize; pre-tested using serological methods for afaltoxin and fumonisin and sent along with all cassava

To IFA-TULLN for LC-MS/MS; state of the art detection capable of quantifying more than 50 toxic metabolites in a single analysis

Sample analyses

Samples milled, sub sampled, and for maize; pre-tested using serological methods for afaltoxin and fumonisin and sent along with all cassava

To IFA-TULLN for LC-MS/MS; state of the art detection capable of quantifying more than 50 toxic metabolites in a single analysis

Sample analyses

Working partnerships and trust established

Survey and analytical methods optimised

Awareness raised

Linkages between mycotoxin prevalence with region and farmer practices identified

Areas for targeted intervention identified

- suitable for scaling out to Africa Rising Action Sites

Summary

Thank you, Asante Sana!