Maternal serum and amniotic fluid bisphenol A concentrations in the early second trimester
Introduction
2, 2-bis(4-Hydroxyphenyl)propane (bisphenol A; BPA), an environmental endocrine-disrupting chemical, has been used in the manufacture of polycarbonate, epoxy resins, and other plastics. Polycarbonate resins are employed for food-contact use, e.g., in food processors, microwave oven-ware, milk and juice containers, baby bottles, and in the interior coatings of cans. Release and migration of BPA monomer from polycarbonate products has been reported [1].
Perinatal exposure of murine fetuses and neonates to BPA at low doses typical for human environmental exposure has produced postnatal estrogenic effects such as increased prostate gland weight [2] and reduced sperm production in male offspring [3], advanced vaginal opening [4] and accelerated growth and puberty in female offspring [5], and disrupted sexual differentiation of the central nervous system and sexual behavior [6].
The perinatal period in mice corresponds to the period of sexual differentiation in the early human second trimester [7]. Human maternal serum (MS) and amniotic fluid (AF) BPA levels during that period have not been undetermined. This study aimed to determine BPA concentrations in the early second trimester over a 10-year period in order to estimate the risk of BPA exposure to human fetuses.
Section snippets
Materials and methods
MS and AF samples were obtained during the preprandial period and stored at −80 °C immediately after centrifugation. Samples were collected at the time of genetic amniocentesis, biochemical, and hormonal analyses with written informed consent. Twenty age-matched paired samples per year between 1989 and 1998 were randomly selected from women carrying fetuses with normal karyotypes (Group I). These 200 Group I women underwent genetic amniocentesis at a mean gestational age±S.D. of 16.3±1.0 weeks
Results
Fig. 1 shows Group I BPA concentrations in MS and AF between 1989 and 1998. The median BPA concentration in MS over the 10-year period was 2.24 ng/ml, and individual values ranged from 0.63 to 14.36 ng/ml. The median AF BPA concentration was 0.26 ng/ml ranging from 0 to 5.62 ng/ml (Fig. 1, Table 1). Over the decade, median BPA MS concentrations significantly decreased from 5.62 in 1989 to 0.99 ng/ml in 1998 (P<0.001, ρ=−0.66), while AF concentrations fluctuated within a range between 0 and 0.68
Discussion
Using the HPLC method, free BPA concentrations in human serum were reported to be 0.32 ng/ml [10] or 0–1.6 ng/ml [11]. A high correlation between the results from a novel ELISA kit used in the present study and the HPLC method was previously confirmed [8]. Although glucuronidation is a major pathway for the metabolism and excretion of BPA in mammals [12], this ELISA kit was able to detect glucuronide-conjugated BPA as well as unconjugated BPA [8]. Recently, using this ELISA method, the mean serum
Acknowledgements
This work was supported in part by Grants-in-Aid from the Ministry of Education, Science, Sports, and Culture; and from the Ministry of Health and Welfare, Japan.
References (17)
- et al.
Exposure to bisphenol A during the fetal and suckling periods disrupts sexual differentiation of the locus coeruleus and of behavior in the rat
Neurosci. Lett.
(2001) - et al.
Serum bisphenol A concentrations showed gender differences, possibly linked to androgen levels
Biochem. Biophys. Res. Commun.
(2002) - et al.
Determination of bisphenol A in human serum by high-performance liquid chromatography with multi-electrode electrochemical detection
J. Chromatogr. B Biomed. Sci. Appl.
(2000) - et al.
Sensitive method for the determination of bisphenol A in serum using two systems of high-performance liquid chromatography
J. Chromatogr. B Biomed. Sci. Appl.
(1999) - et al.
Decrease of PCDD/F levels in human blood from Germany over the past ten year (1989–1998)
Chemosphere
(2000) - et al.
Estrogen receptor-mediated effects of a xenoestrogen, bisphenol A, on preimplantation mouse embryos
Biochem. Biophys. Res. Commun.
(2000) - et al.
Chromosomal congenital anomalies and residence near hazardous waste landfill sites
Lancet
(2002) - et al.
Migration of bisphenol A from can coating to drinks
J. Food Hyg. Soc. Jpn.
(1999)