Aflatoxin M1 in raw, pasteurized and powdered milk available in the Syrian market

Abstract

The incidence of contamination of aflatoxin M1 (AFM1) in milk samples collected from the Syrian market was investigated by using the competitive enzyme linked immunosorbent assay (ELISA) technique. A total of 126 samples composed of raw cow milk (74 samples), raw sheep milk (23), raw goat milk (11), pasteurized cow milk (10) and powdered milk (8) showed that 80% of tested samples were contaminated with various levels of AFM1 ranging from >20 to 765 ng/l. Percentages of AFM1-contaminated samples exceeding the American, Syrian and European tolerance limits were 22%, 38% and 52%, respectively. The range of contamination was relatively higher in pasteurized milk than in raw cow and sheep milk. 80% of AFM1-contaminated pasteurized cow milk samples exceeded the European tolerance limit with a range of contamination between 89 and 765 ng/l. Percentages of contaminated raw cow, sheep and goat milk exceeding the European tolerance limit were 59%, 24% and 14%, respectively. Milk powder was almost free of AFM1 contamination with only one sample containing a concentration lower than the European tolerance limit (12 ng/l). Extrapolation of aflatoxin B1 (AFB1) from AFM1 levels of contamination in milk samples indicates that contamination in dairy cattle feeds may range from 0.5 to 47.8 μg/kg.