Aflatoxin Contamination in Agri-Food Systems: A Comprehensive Review of Toxicity, Food Security, Economic Impacts, and Sustainable Mitigation Across the Value Chain.

Aflatoxins (AFs) are highly toxic and carcinogenic secondary metabolites produced mainly by Aspergillus flavus and Aspergillus parasiticus, posing serious threats to global food safety, public health, and agricultural economies, particularly in tropical and subtropical regions. This review synthesizes current evidence on the types, sources, and mechanisms of AF toxicity, emphasizing their widespread prevalence in staple crops such as maize, groundnuts, and rice. Climate change, poor agricultural practices, and inadequate storage conditions exacerbate contamination risks. Chronic AF exposure is associated with hepatocellular carcinoma, immune suppression, stunted growth in children, and acute poisoning episodes, such as the 2004 Kenyan outbreak that resulted in 125 deaths. Economically, AFs lead to an estimated USD 6-18 billion in annual losses due to trade rejections, healthcare costs, and productivity decline. This review also explores recent advances in sustainable and innovative mitigation strategies across pre- and post-harvest stages. These include the use of atoxigenic biocontrol strains, genetic resistance, natural inhibitors, hermetic storage technologies, nanotechnology, biological detoxification, and climate-smart agricultural practices. Additionally, emerging digital tools such as Internet of Things (IoT) sensors, blockchain-based traceability, and machine learning models offer promising approaches for real-time monitoring and predictive risk assessment. Despite these advancements, major challenges remain, including limited detection infrastructure, low awareness among smallholder farmers, and fragmented policy enforcement. The review concludes by emphasizing the need for integrated, multi-sectoral interventions anchored in a One Health approach to reduce aflatoxin risks, promote food security, and safeguard human and environmental health globally.