Aflatoxins, ochratoxin A and zearalenone in tiger nut drinks in Lagos, Nigeria

Tiger nuts, widely consumed in Nigeria, are prone to fungal contamination. Yet, little is known about the mycotoxin burden in drinks derived from them. This study validated and applied high-performance liquid chromatography with fluorescence detection (HPLC-FLD) to determine aflatoxins (AFs), ochratoxin A (OTA) and zearalenone (ZEN) in 30 tiger nut drink samples from Lagos, Nigeria, after immunoaffinity cleanup. Calibration curves showed good linearity (r2 > 0.98), recoveries ranged 76% - 113% and relative standard deviations were below 20%. Limits of detection were 0.44 µg/kg for AFB1, 0.33 µg/kg for OTA and 5.82 µg/kg for ZEN. Contamination rates were 13.3% for AFB1, 6.7% for total AFs, 30% for OTA and 20% for ZEN. This report provides a validated HPLC method and occurrence data that may support further routine monitoring and risk assessment of mycotoxins in tiger nut drinks.