Carryover of Aflatoxin From Dairy Feed to Milk: A Systematic Review (1 January 2004-31 December 2024)

Aflatoxins, toxic metabolites produced by Aspergillus species, are frequently reported contaminants of dairy cattle feed worldwide, particularly in tropical and subtropical regions where climatic conditions favor fungal growth, and they can be transferred into milk and dairy products. Their presence poses major public health risks, including liver cancer and growth impairment, among others. Understanding the extent of carryover from feed to milk is critical for food safety and regulatory control. A systematic review was conducted to synthesize evidence on aflatoxin carryover in dairy systems over the past two decades. Literature searches were performed in PubMed, Scopus, Web of Science, and Embase. Studies investigating aflatoxin levels in dairy feed and milk, as well as carryover rates, were included. Data extraction focused on contamination levels, feed treatment efficiency and carryover rates of aflatoxins as well as mitigation measures. Twenty-seven eligible studies were identified. Aflatoxin B₁ concentrations in dairy feed ranged from undetectable to 598 µg/kg. In milk, AFM₁ levels reached up to 22.2 µg/kg, with reported carryover rates as high as 15%. The findings highlight variability in contamination across regions and production systems. This review underscores the continuing risk of aflatoxin in dairy products, identifies knowledge gaps and emerging threats, and emphasizes the need for improved interventions to safeguard food safety and public health.