ENDOCRINE DISRUPTOR BISPHENOL A: OCCURRENCE IN HUMAN COLOSTRUM, BREAST MILK AND INFANT FORMULA

Bisphenol A o 2,2-bis (4-idrossifenil) propano (BPA), an endocrine disruptor (ECDs), is a synthetic phenolic compound employed in the production of polycarbonate and epoxy resins used in food containers [1]. Mothers are exposed through the diet and, during pregnancy, ECDs can be transferred to the fetus across the placenta, and to the newborn baby by breastfeeding. Infant exposure may be also the consequence of raw material contamination for infant formula [2]. BPA may have effects on mammary gland, reproductive, neurobehavioral, metabolic system, and also on the immune system. The European Food Safety Authority fixed a Tolerable Daily Intake of 4 µg/kg bw/day [3]. Effects of exposure can be particularly harmful to the fetus, infants, and young children, due to their lack of metabolic enzymes capable of conjugating BPA. The vulnerability of humans during the neonatal and prenatal periods makes the BPA intake assessment more important for infants. To evaluate the infant exposure, as biomarkers of infant exposure, BPA contamination levels in colostrums, breast milk and infant formula collected from different geographic areas were considered. Biomonitoring studies suggested higher levels of BPA in human colostrums than in breast milk. In 101 samples of colostrum, BPA was detected at a range of 1-7ng/ml (mean level of 3.41ng/mL) [2]. As a biomarker of exposure, noticeable differences were reported in human milk. In breast milk of 23 healthy women, BPA was at a range of 0.28-0.97 ng/ml (mean 0.61 ng/mL) [2]. Other studies reported BPA levels up to 6. 3 ng/mL in 60% of human breast milk samples. Liquid infant formula showed BPA levels below the permissible limit (0.1-13.2 ng/g), while powder formula showed levels (0.13-2.6 ng/g) even lower [4]. BPA finds its way into food via miscellaneous pathways. High levels of BPA in breast milk may be due to differences in exposure, lifestyle and inefficient metabolism [5]. Infrequent use of all-metal cans, a limited contact area with epoxy phenolic coatings, resistance to mass transfer between packaging and solid food can explain the low concentrations detected in powder formula[6]. Infants and children are particularly vulnerable to the effects of exposure to BPA [7]. Further studied are recommended, considering children explicitly as a relevant and vulnerable group to BPA contamination levels of human milk and infant formula.