Survey of breakfast and infant cereals for aflatoxins B₁, B₂, G₁ and G₂

Abstract

Three hundred and forty-nine breakfast and infant cereal samples were collected at retail level across Canada from 2002 to 2005. They included rice-, soy-, barley-based and mixed-grain infant cereals, corn-, wheat-, rice-based and mixed-grain breakfast cereals, and were analysed for aflatoxins B₁, B₂, G₁ and G₂ using a modified AOAC International official method. An immunoaffinity column was used for the cleanup and purification of extracts. Determination of aflatoxins was by LC using post-column derivatization with pyridinium hydrobromide perbromide and fluorescence detection. Results indicated that 50% of both breakfast and infant cereals had detectable levels (limit of detection = 0.002 ng g⁻¹) of aflatoxin B₁, which is the most toxic of the four toxins. The levels found varied from 0.002 to 1.00 ng g⁻¹ for aflatoxin B₁, from 0.002 to 0.14 ng g⁻¹ for aflatoxin B₂, from 0.008 to 0.27 ng g⁻¹ for aflatoxin G₁, and from 0.008 to 0.048 ng g⁻¹ for aflatoxin G₂. Only 4% of the breakfast cereals and 1% of the infant cereals had aflatoxin B₁ levels exceeding 0.1 ng g⁻¹, which is the European Union maximum limit for aflatoxin B₁ in baby foods and processed cereal-based foods for infants and young children.

Keywords:

• Aflatoxin B₁
• infant cereals
• breakfast cereals
• immunoaffinity column
• liquid chromatography