Chemical contaminants in breast milk: a brief critical overview

Breast milk is the reference food for the infant both for its content in nutrients, necessary for normal growth and development, and for the presence of biologically active substances that provide protection from infections and a lower susceptibility to several non-communicable diseases typical of adulthood. However, substances that the mother assimilates from the environment, and which can be potentially harmful, can be concentrated in breast milk. In fact, for a long time, breast milk has been considered a reliable biomarker of the environment. The huge increase in the production and use of chemicals that has occurred in recent decades with consequent wide dispersion in the soil, water and air makes it necessary to carefully evaluate the levels of contamination. Based on a synthetic review of current knowledge, it can be confirmed that breast milk is always the first choice. However, various aspects remain to be clarified based on more robust scientific data. This review aims to stimulate further research, managed by multi-disciplinary teams which, with the use of the most modern chemical analysis tools, determine the presence of exogenous chemicals in longitudinal studies during pregnancy and lactation, clarifying their metabolic fate and evaluating them in the 'scope of global exposure (exposome). To this end, the gaps present in the studies conducted so far are also highlighted to make future scientific approaches increasingly robust.