NIVELES DE AFLATOXINA M1 EN LECHE CRUDA Y PASTEURIZADA COMERCIALIZADA EN LA ZONA METROPOLITANA DE GUADALAJARA, MéXICO

aflatoxin m1 (afm1) is a milk hygiene quality indicator established in mexico. aflatoxin m1 is a metabolite of aflatoxin b1 (afb1), becoming from contaminated feed. the thermal treatments usually applied to raw milk did not reduce the concentrations on afm1 in milk. the aim of the present work was to conduct a screening of afm1 i raw (n=50) collected from raw milk collecting facilities and 7 pasteurized milk brand (n=84) samples. all the samples tested were both produced in jalisco state and commercialized in guadalajara, mexico. the analyses were performed using the competitive direct elisa kit agraquant？ aflatoxin m1 (romer labs). statistical analysis was performed using a one-way anova by sigma stat 3.0 program. afm1 was found in 100% of the tested samples, ranging from < 0.005 to 0.100 μg/l in raw milk, and from < 0.005 to 0.637 μg in pasteurized milk. a total 18.6% (25/134) samples showed levels above maximum residue limit (mrl) established by the european community (0.05 μg/kg), 0.7% (1/134) for raw and 17.9% (24/134) for pasteurized milk. only 0.7% (1/134) of the tested samples exceeded this mrl established in mexico by nom-243-ssa1-2010 which is 0.5 μg/l afm1. statistical differences were found (p<0.05) between sampling months; the highest level was detected in december, while no differences were detected among milk collecting facilities and either among pasteurized milk brands.