Aflatoxin M1 Contamination of Milk and Its Products in Bomet County, Kenya

Aflatoxin M1 (AFM1) is a major carcinogenic compound that may be found in milk and dairy products resulting from ingestion of aflatoxin B1 by dairy animals. The study aimed at determining the level of aflatoxin M1 in milk and milk products from Bomet County. A total of 185 samples (150 raw milk and 35 processed milk and milk products) were randomly collected from milk collection sites and randomly selected milk kiosks respectively. The AFM1 was analyzed using a commercial ELISA kit (Ridascreen, aflatoxin M1 R-Biopharm, Product code, R5812, Darmstadt, Germany). Out of 185 samples investigated, 156 samples were positive for AFM1, an overall contamination rate of 84.32%. The samples with levels higher than the tolerance limit of 0.05 μg/l recommended by Food and Agriculture Organization (FAO) and World Health Organization (WHO) limits were 43.8% mainly contributed by the raw milk compared to processed milk (52.0% versus 8.6%). Processed milk had insignificant level of contamination with aflatoxin M1 (Median 0.00 (IQR: 0.00, 0.00 μg/l) with a minimum of 0.00 μg/l and a maximum of 0.69 μg/l. Raw milk showed significant contamination, median 0.09 (IQR: 0.00, 0.50) μg/l with a minimum of 0.00 μg/l and a maximum of 2.93 μg/l. Although there was no significant differences in AFM1 levels with study sites (P = 0.217); the median levels of aflatoxin M1 was high in sites 1, 3, and 7. The sites that had median aflatoxin M1 levels below the WHO/FAO acceptable limits of 0.05 μg/l were sites 2, 4 and 6. Due to high incidence of AFM1 contamination of milk and milk samples in Bomet County, there is need for regular monitoring and regulation of AFM1 contamination in milk and its products in the County.