Background – what are aflatoxins and their impacts
Aflatoxins are highly toxic compounds produced by certain strains of Aspergillus fungi, particularly A. flavus and A. parasiticus. These toxins, regulated at very low levels (parts per billion, ppb), affect several staple and cash crops in many countries in Africa, including maize, groundnut, sorghum, and chilies. In tropical and subtropical regions, favorable climate conditions promote aflatoxin production. In addition, climate change is worsening the aflatoxin challenge, disproportionately affecting low- and middle-income countries, while in high-income countries the negative effects are somehow mitigated because of reliable infrastructure, testing capacity, and strict regulations.
The health impacts of aflatoxins are alarming, particularly in Africa. Chronic exposure is linked to various types of cancer, stunting, immune system suppression, and other longterm problems, while acute poisoning has led to fatal outbreaks, especially in East Africa. The African Union’s Partnership for Aflatoxin Control in Africa (PACA) estimates of annual health costs are staggering: US$ 1.6 billion for Nigeria, US$ 1.1 billion for Tanzania, and US$ 577 million for Uganda! Beyond human health, aflatoxins also frequently affect livestock, fisheries, and pets with the most recent reports (2024) being from South Africa, DR Congo, Zambia, and Malawi.
Aflatoxins severely impact Africa’s agricultural trade. Crops exceeding aflatoxin tolerance thresholds cannot enter premium local, regional, or international markets. Countries like Uganda and Tanzania have faced bans on maize exports from Kenya, Burundi, and South Sudan, disrupting local economies, disturbing regional harmony, and driving up poverty in rural areas. Companies whose products are banned suffer reputational damage and financial losses. Local food, feed, and brewing industries often reject locally-produced crops and have no other option but to import grains. Recurrent contamination continues to reduce Africa’s ability to benefit from trade opportunities, causing hundreds of millions of dollars in losses annually and stalling economic growth.
The situation calls for stronger regulatory frameworks, increased monitoring, and climate-adaptive strategies to minimize the pervasive impact of aflatoxins across the continent.
What solutions are available?
Addressing aflatoxin contamination through effective management strategies is critical for improving farmer livelihoods and ensuring food security and safety across Africa. Various management strategies have been developed, including improved pre- and postharvest agricultural practices, tolerant varieties (although not always effective), post-harvest handling (e.g., drying and storage), and biocontrol technologies (e.g., Aflasafe).
A carefully selected combination of aflatoxin management tools, tailored to specific situations, can achieve more cost-effective aflatoxin reduction throughout the value chain.
Biocontrol as a centerpiece of integrated management strategies
An effective intervention is the use of Aflasafe, a bioprotectant developed by IITA in partnership with the United States Department of Agriculture – Agricultural Research Service (USDA-ARS), and several national and international partners. Aflasafe products contain non-toxin-producing (atoxigenic) strains of A. flavus native to the target countries. These strains outcompete toxin-producing strains, effectively reducing aflatoxin contamination in crops by 80% to 100% compared to non-treated crops. Currently, products are commercially available for use in 12 countries (see map). More products are being developed for another 11 countries.
What policy efforts made by governments and/or economic blocks can be capitalized?
Due to the importance of aflatoxins, African Union Commission created Partnership for Aflatoxin Control in Africa (PACA) to address the aflatoxin problem in Africa through a comprehensive set of policies and programs. Also, policies to prevent contamination and exposure have been launched by Regional Economic Communities [East African Community (EAC) and Economic Community of West African States (ECOWAS)], and individual Governments (e.g., Ghana). Frameworks to prevent contamination and exposure exist but need to be implemented at scale to reduce contamination and exposure on the ground.
Conclusion
Addressing the aflatoxin challenge is critical for improving food security, health outcomes, and economic stability in Africa. The adoption of integrated management strategies provides a sustainable and effective strategy for reducing aflatoxin contamination in crops. To ensure widespread impact, farmer organizations, governments, international organizations, the private sector, and research institutions must make decisive and concerted efforts to vigorously promote adoption of these strategies, build capacity, and develop supportive policies. By integrating these strategies, Africa can reduce the health risks associated with aflatoxins while also contributing to broader development goals, leading to achieve at least 55 targets across 13 of the 17 Sustainable Development Goals (SDGs) in countries where the Aflasafe Initiative operates.
This work was conducted as part of the CGIAR Initiative on Plant Health, now integrated into the CGIAR Sustainable Farming Science Program.
