Determination of Aflatoxin M1 in Breast Milk Samples in Isfahan, Iran

Aflatoxins are highly toxic, immunosuppressive, mutagenic, teratogenic, and carcinogenic compounds. Aflatoxin M1 (AFM1) is a hydroxylated metabolite of aflatoxin B1 (AFB1) formed in liver and excreted into breast milk. It is considered to impose certain hygienic risks to infant health. The aim of this study was to evaluate the presence of aflatoxin in breast milk using AFM1 in milk as a biomarker for exposure to AFB1. We also tried to determine the level of AFM1 in lactating mothers in Isfahan, Iran.

The study was carried out on 80 lactating women who were randomly selected from 2 urban health centers. Milk samples and information on food intake were collected from the participants using the structured food-frequency questionnaire. Breast milk samples were tested to determine AFM1 levels by a competitive enzyme-linked immunosorbent assay (ELISA) technique.

Our findings showed that the incidence of contamination with AFM1 in our participants was 1.25%. AFM1 was found only in one sample at a concentration of 6.8 ng/L. Chi-square analysis revealed the presence of AFM1 to be significantly associated with consumption of sausages (P < 0.001). AFM1 level was found to be lower than the maximum tolerable limit (25 ng/l) accepted by the European Communities and Codex Alimentarius.

The benefits of breast milk have been well documented. Therefore, early childhood exposure to the environmental toxicants like aflatoxins may be a critical determinant of later health effects. The findings of this study pointed out that AFM1 was present in only one milk sample. The findings confirmed the need for developing strategies to reduce exposure to aflatoxin in foods and also to routinely carry out biological monitoring of aflatoxins as a food quality control measure.