Survey of aflatoxin M sub(1) in cows' milk from free-grazing cows in Abeokuta, Nigeria

Aflatoxin M sub(1) (AFM sub(1)) in milk from 100 different herds of free-grazing cows in Abeokuta, Nigeria, was analysed by immunoaffinity column cleanup and HPLC with fluorescence detection. AFM sub(1) was found in 75 % of the samples, the toxin levels in positive samples ranged from 9.0 to 456.0 ng/l. The mean AFM sub(1) level in positive samples was 108.15 ng/l, exceeding, for example, the European Union maximum level by a factor of two. These results indicated that there is an urgent need to more closely control the milk of free-grazing cows for AFM sub(1) in order to protect the health of humans consuming milk and milk products.