Aflatoxin M1 contamination of human breast milk in Isfahan, Iran

During the last decades there has been great attention paid to aflatoxins. They are highly toxic, immunosuppressive, mutagenic, teratogenic, and carcinogenic compounds. Aflatoxin M1 (AFM1), a hydroxylated metabolite of aflatoxin B1 (AFB1), is formed in the liver and excreted into the breast milk. It is considered to cause certain hygienic risks for infant health. The aim of this study was to evaluate the presence of the AFM1 in the breast milk using AFM1 in milk as a biomarker for exposure to aflatoxin B1 and determine the level of AFM1 contamination in the lactating mothers in Isfahan, Iran.

This study was carried out on 80 lactating women randomly selected from two urban health centers. Mother's milk samples and information on food intake were collected from the participants using structured food-frequency questionnaire. Breast milk samples were tested for AFM1 by a competitive ELISA technique.

Our findings showed that only one sample was contaminated with AFM1 with concentrations of 6.8 ng/L. However, the AFM1 level in this sample was lower than the maximum tolerable limit (25 ng/L) accepted by the European Communities and Codex Alimentarius.

Although the concentration of AFM1 in none of the samples was higher than the acceptable level, the presence of AFM1 in only one of them confirms the need for developing strategies to reduce exposure to aflatoxin in foods and to carry out biological monitoring of aflatoxins as a food quality control measure routinely.