Determination of aflatoxin M₁ in breast milk as a biomarker of maternal and infant exposure in Colombia

Abstract

Chronic exposure to aflatoxins, and especially to aflatoxin B₁ (AFB1), causes hepatocellular carcinoma with prevalence 16–32 times higher in developing compared with developed countries. Aflatoxin M₁ (AFM1) is a monohydroxylated metabolite from AFB1 that is secreted in milk and which can be used as a biomarker of AFB1 exposure. This study aimed to determine AFM1 levels in human breast milk using immunoaffinity column clean-up with HPLC and fluorescence detection. Breast milk samples were obtained from 50 nursing mothers. Volunteers filled in a questionnaire giving their consent to analyse their samples as well as details of their socioeconomic, demographic and clinical data. The possible dietary sources of aflatoxins were assessed using a food frequency questionnaire. A total of 90% of the samples tested positive for AFM1, with a mean of 5.2 ng l⁻¹ and a range of 0.9–18.5 ng l⁻¹. The study demonstrated a high frequency of exposure of mothers and neonates to AFB1 and AFM1 in Colombia, and it points out the need to regulate and monitor continuously the presence of aflatoxins in human foods. Further research is needed in order to determine the presence of other mycotoxins in foods and in human samples as well as to devise protection strategies in a country where mycotoxins in human foods are commonly found.

Graphical Abstract

Keywords:

• aflatoxins
• aflatoxin M₁
• exposure
• breast milk
• infant

Acknowledgements

The authors thank Dr Herman Boermans for constructive comments made on the manuscript.

ORCID

G.J. Diaz http://orcid.org/0000-0002-9858-0845

M.P. Sánchez http://orcid.org/0000-0002-5717-8585

Additional information

Funding

This work was partially funded by the College of Medicine, National University of Colombia [grant number 202010018822].