Phthalate esters in human milk: Concentration variations over a 6-month postpartum time

The present study investigated the levels of phthalate esters in a total of 86 human milk samples collected among 21 breast-feeding mothers over a 6-month postpartum time. Di(2-ethylhexyl) phthalate (DEHP) was the predominant ester with the arithmetic mean value of 222 ng g(-1) (range: 156-398 ng g-1, 95% confidence limit), followed by dibutyl phthalate (DBP), 0.87 (range: 0.62-1.2) ng g(-1). Diethyl phthalate (DEP), with a mean of 0.31 ng g(-1), was detected in only a small number of samples. Weak correlations between lipid content and levels of phthalate esters were observed. The levels of phthalate esters in human milk fluctuated over the 6-month period; this may indicate a need for multiple sample collection, to calculate average concentrations over the feeding period. Multiple sample collection would provide a better estimate of the exposure of breast-fed infants to phthalate in human milk. For infants relying on breast-feeding, the mean daily intake over the first 6-month period considering a 7 kg infant consuming 750 g of milk was estimated at 167 Ag d(-1) for DEHP and less than 1 Ag d(-1) for DBP and DEP. While the nutritional and social benefits of breast-feeding are well established, the potential transfer of phthalate esters from mothers to breast- fed infants should also be recognized.