Phthalate Diesters and Their Metabolites in Human Breast Milk, Blood or Serum, and Urine as Biomarkers of Exposure in Vulnerable Populations

Abstract

BackgroundPhthalates may pose a risk for perinatal developmental effects. An important question relates to the choice of suitable biological matrices for assessing exposure during this period.ObjectivesThis study was designed to measure the concentrations of phthalate diesters or their metabolites in breast milk, blood or serum, and urine and to evaluate their suitability for assessing perinatal exposure to phthalates.MethodsIn 2001, 2–3 weeks after delivery, 42 Swedish primipara provided breast milk, blood, and urine samples at home. Special care was taken to minimize contamination with phthalates (e.g., use of a special breast milk pump, heat treatment of glassware and needles, addition of phosphoric acid).ResultsPhthalate diesters and metabolites in milk and blood or serum, if detected, were present at concentrations close to the limit of detection. By contrast, most phthalate metabolites were detectable in urine at concentrations comparable to those from the general population in the United States and in Germany. No correlations existed between urine concentrations and those found in milk or blood/serum for single phthalate metabolites. Our data are at odds with a previous study documenting frequent detection and comparatively high concentrations of phthalate metabolites in Finnish and Danish mothers’ milk.ConclusionsConcentrations of phthalate metabolites in urine are more informative than those in milk or serum. Furthermore, collection of milk or blood may be associated with discomfort and potential technical problems such as contamination (unless oxidative metabolites are measured). Although urine is a suitable matrix for health-related phthalate monitoring, urinary concentrations in nursing mothers cannot be used to estimate exposure to phthalates through milk ingestion by breast-fed infants.

Adverse effects of endocrine disruptors on the foetal testis development: focus on the phthalates.

“…In an epidemiologic study, 75% of the 289 human subjects tested were positive for the presence of four different types of phthalates in their urine samples [35]. The concentration of phthalates in biological fluids in humans show large individual variations [36][37][38][39][40][41]. Values for MEHP are reported in Table 1.…”

Gender-specific relationship between prenatal exposure to phthalates and intrauterine growth restriction

“…human burden of phthalates has been reported and the consensus is that phthalate metabolites in urine could be used for assessing phthalate exposure in humans (4)(5)(6)(7)(8)(9)(10)(11). In most cases, it is the monoester metabolites that have been claimed to be responsible for adverse health effects (12,13).…”

Effects of Endocrine-disrupting Chemicals on Female Reproductive Health

“…It is non-covalently bound to plastics, and can leach out of these products, resulting in potential daily human exposure in the range of 3-30 μg/kg/day [213]. In fact DEHP and its metabolites have been found in breast milk, serum, amniotic fluids and sweat [215,216] and recently in urine samples from mothers and infants [217]. One the most vulnerable populations are infants in neonatal intensive care units or NICUs, whose daily exposure reaches 22.6 mg/kg [213].…”