Diet Quality and Health of the Poor

Aflatoxin and Child Stunting in Kenya

Aflatoxin is a known toxin that resides in soil and enters plants.  There is no technology to prevent entry of aflatoxin into the food chain in the field.   Although aflatoxin is harmful to humans, much remains unknown about its specific effects, specifically what the impact is of consuming small or moderate levels of aflatoxin over a long period. Because foods essential to food security in much of the world are vulnerable to aflatoxin, clarification of its impact is important.  This study is designed to yield practical information to guide governments and consumers in protecting against aflatoxin.

IFPRI, ASI, ACDI-VOCA, CARITAS Meru, and APHRC are studying 65 villages in Meru in the Eastern province of Kenya. This is a region where aflatoxin contamination occurs naturally in maize (as well as in other food crops and livestock products), depending upon weather, farming, and storage practices. The study objectives are to: (i) identify storage practices that will reduce aflatoxin contamination, and (ii) introduce maize testing and swapping to study the impact of reduced aflatoxin exposure on child growth. Households with children under 2 years of age from the study villages will be invited to participate in the study. Information on the health effects of aflatoxin and mitigation strategies will be provided to all households in all study villages. In addition, 15 villages will be randomly selected to be in an intervention group to which cheap improved post-harvest and storage practices are provided. A further 25 villages will be randomly selected to be in an intervention group in which maize is tested and contaminated maize is swapped for clean maize. The remaining villages will form a comparison group.

Aflatoxin levels and child growth rates at baseline and follow-up will be compared across the intervention and comparison groups to answer the following questions:

  • Does reduced aflatoxin consumption improve child growth?
  • What is the effectiveness of cheap post-harvest and storage practices for reducing aflatoxin contamination in household maize stores?
  • How can cheap aflatoxin testing reduce aflatoxin contamination?

There are potential ethical implications of a study that assesses the health effects of a toxin. This study has been designed to provide the data required to induce changes in policy and practice, such as the commitment of more resources to aflatoxin mitigation and practical guidance on how resources can be used to reduce aflatoxin exposure, while reducing exposure risks for all study participants, both those in the intervention groups and those in the comparison group. The project has undergone a full ethics review and has been approved by both the IFPRI Institutional Review Board (IRB) and a local IRB in Kenya called AMREF. AMREF IRB is accredited by the National Bioethics Committee (the national committee established by the National Council of Science and Technology mandated to promote and monitor ethical practices in Kenya).

The following Q&A provides specific information regarding the project’s design and ethical considerations.

Q: There is an ethical concern in allowing populations including pregnant mothers and children to consume maize that is likely to be contaminated with aflatoxin. What has the project done to address this concern?

A: No one is exposed to more aflatoxin by being in the study than they would be exposed to if they were not in the study. The study design actually reduces exposure to aflatoxin for all study households, including households in the comparison group, by providing information regarding the health effects of aflatoxin and mitigation strategies in all study villages. We thus expect that health risks will be lower in our study villages than in non-study villages in the same area consuming the same maize-based diets.

Q: How does the study take into account the views of the people in the study villages?

We undertook background research to understand what type of support households in Meru county would like to reduce aflatoxin levels. Households reported that they would appreciate more information and training on aflatoxin. This suggests that providing information in all study villages will be useful in reducing aflatoxin contamination. Households also indicated that interventions to encourage improved post-harvest practices and to test and replace contaminated maize with clean maize would be well-received. We also asked households how they would feel about being in an intervention study, and responses were positive.

Q: What was done to inform potential study participants in advance about the study’s objectives and design?

A: We engaged in extensive group and individual conversations with each of the study villages to provide information about the study and its conduct. Fully informed prior consent was obtained from all participants prior to beginning the study, and all study participants know nthat they can withdraw from the study at any time. Although most households have chosen to participate in the study, some have not.

Q: Did Kenyan authorities approve the study in advance and are they included in the study?

A: During the planning of the study, we met with the Ministries of Agriculture, and Public Health and Sanitation at central and local levels to explain and discuss the study objectives. We subsequently received official letters of support for the project from both Ministries. We have built on this official support to work with local officials in Meru—informing them and receiving their advice and approval—as we implement the research project.

Q: What will be done with the information collected regarding aflatoxin levels?

A: Firstly, any maize known to be contaminated will be destroyed and replaced with uncontaminated maize. Secondly, we have worked with all households in the village to agree on a plan to communicate information regarding the aflatoxin exposure of households. Finally, the results of our research will be shared with all of the study villages. We will ensure that the research findings are presented in an accessible manner to all households (whether literate or not) and in a participatory forum so that questions on the results of the research can be asked and discussed.

Q: Are project activities focused on specific groups of households that might be more at risk of aflatoxin exposure.

All of the participants in our study are households that have children under the age of 2 during the course of our study. This is because ensuring good nutritional intake of children under 2 is particularly important. We will be working with both the mothers of these children and any other members of the household that make decisions regarding the post-harvest management of maize.

For more information regarding aflatoxins see:
New Study Documents Spread of Aflatoxins in Kenya