Phthalate diesters and their metabolites in human breast milk, blood or serum, and urine as biomarkers of exposure in vulnerable populations.
BACKGROUND
Phthalates 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.


OBJECTIVE
This 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.


METHODS
In 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).


RESULTS
Phthalate 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.


CONCLUSIONS
Concentrations 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.
Högberg
Johan
J
Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden. johan.hogberg@ki.se
Hanberg
Annika
A
Berglund
Marika
M
Skerfving
Staffan
S
Remberger
Mikael
M
Calafat
Antonia M
AM
Filipsson
Agneta Falk
AF
Jansson
Bo
B
Johansson
Niklas
N
Appelgren
Malin
M
Håkansson
Helen
H
D015415:Biomarkers / Q000032:analysis; D004952:Esters / Q000032:analysis* / Q000097:blood / Q000652:urine; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D018811:Maternal Exposure; D008895:Milk, Human / Q000737:chemistry*; D010795:Phthalic Acids / Q000032:analysis* / Q000097:blood / Q000652:urine
D015415:Biomarkers; D004952:Esters; D010795:Phthalic Acids