High urinary phthalate concentration associated with delayed pubarche in girls

Department of Growth and Reproduction, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark.
International Journal of Andrology (Impact Factor: 3.21). 03/2012; 35(3):216-26. DOI: 10.1111/j.1365-2605.2012.01260.x
Source: PubMed

ABSTRACT Phthalates are a group of chemicals present in numerous consumer products. They have anti-androgenic properties in experimental studies and are suspected to be involved in human male reproductive health problems. A few studies have shown associations between phthalate exposure and changes in pubertal timing among girls, although controversies exist. We determined the concentration of 12 phthalate metabolites in first morning urine samples from 725 healthy Danish girls (aged 5.6-19.1 years) in relation to age, pubertal development (breast and pubic hair stage) and reproductive hormone levels (luteinizing hormone, oestradiol and testosterone). Furthermore, urinary phthalates were determined in 25 girls with precocious puberty (PP). In general, the youngest girls with less advanced pubertal development had the highest first morning urinary concentration of the monobutyl phthalate isoforms (∑MBP((i+n))), monobenzyl phthalate (MBzP), metabolites of di-(2-ethylhexyl) phthalate (∑DEHPm) and of di-iso-nonyl phthalate (∑DINPm). After stratification of the urinary phthalate excretion into quartiles, we found that the age at pubarche was increasing with increasing phthalate metabolite quartiles (except for MEP). This trend was statistically significant when all phthalate metabolites (except MEP) were summarized and expressed as quartiles. No association between phthalates and breast development was observed. In addition, there were no differences in urinary phthalate metabolite levels between girls with PP and controls. We demonstrated that delayed pubarche, but not thelarche, was associated with high phthalate excretion in urine samples from 725 healthy school girls, which may suggest anti-androgenic actions of phthalates in our study group of girls.

1 Follower
  • [Show abstract] [Hide abstract]
    ABSTRACT: The age of pubertal onset for girls has declined over past decades. Research suggests that endocrine disrupting chemicals (EDCs) may play a role but exposure at multiple stages of development has not been considered. We examined in utero and peripubertal exposure to bisphenol-A (BPA) and phthalates in relation to serum hormones and sexual maturation among females in a Mexico City birth cohort. We measured phthalate metabolite and BPA concentrations in urine collected from mothers during their third trimester (n=116) and from their female children at ages 8-13 years (n=129). Among girls, we measured concurrent serum hormone concentrations, Tanner stages for breast and pubic hair development, and collected information on menarche onset. We used linear and logistic regression to model associations between in utero and peripubertal measures of exposure with hormones and sexual maturation, respectively, controlling for covariates. An interquartile range (IQR) increase in in utero urinary mono-2-ethylhexyl phthalate (MEHP) was positively associated with 29% (95% CI: 9.2-52.6%) higher dehydroepiandrosterone sulfate (DHEA-S), an early indicator of adrenarche, and 5.3 (95% CI: 1.13-24.9) times higher odds of a Tanner stage >1 for pubic hair development. Similar relationships were observed with other in utero but not peripubertal di-2-ethylhexyl phthalate (DEHP) metabolites. IQR increases in in utero monobenzyl phthalate (MBzP) and monoethyl phthalate (MEP) were associated with 29% and 25% higher serum testosterone concentrations (95% CI: 4.3-59.3; 2.1-54.1), respectively. In addition, we observed suggestive associations between in utero and peripubertal MEP concentrations and increased odds of having undergone menarche, and between peripubertal MnBP concentrations and increased odds of having a Tanner stage >1 for both breast and pubic hair development. BPA was not associated with in utero or peripubertal serum hormones or sexual maturation.
    Environmental Research 08/2014; 134C:233-241. DOI:10.1016/j.envres.2014.08.010 · 3.95 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Polycystic Ovary Syndrome (PCOS) is an endocrine-metabolic disorder that affects approximately 6-10% of women of child-bearing age. Although preliminary studies suggest that certain pollutants may act as endocrine disruptors in animals, little is known about their potential association with PCOS. The objective of this case-control pilot study is to determine whether women with PCOS have higher concentrations of specific environmental contaminants compared to women who have not developed PCOS.
    BMC Endocrine Disorders 10/2014; 14(1):86. DOI:10.1186/1472-6823-14-86 · 1.67 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Phthalate esters are widely used plasticizers that are present in many daily used products. Although some of their reproductive effects have been reported, pubertal development effects from prenatal exposure to phthalates awaits further investigations. A population based birth cohort was established (N=437 at baseline) with maternal exposure to phthalates assessed in urine collected at the third trimester of pregnancy in 2001 and 2002. Their 133 children with prenatal phthalates exposure were followed up for the outcomes of pubertal development by sequential physical examinations at eight and 11 years old in 2009 and 2012. Urinary concentrations of major phthalate metabolites (i.e., mono-2-ethylhexyl phthalate [MEHP], mono-(2-ethyl-5-hydroxyhexyl) phthalate [MEHHP], mono-(2-ethyl-5-oxohexyl) phthalate [MEOHP], mono-butyl phthalate [MBP], mono-benzyl phthalate [MBzP], monomethyl phthalate [MMP], and mono-ethyl phthalate [MEP]) were determined using liquid chromatography linked to tandem mass spectrometry. The reproductive development measurements included bone age (for both genders), testicle size (for boys), uterus size, and ovarian volume (for girls). We reported results of 133 children with complete data by applying generalized estimating equations for the repeated continuous outcomes. After controlling for Tanner stage, we detected a significant association between reduced uterus size and increasing phthalate exposure in the 2(nd) tertile relative to the 1st tertile of creatinine-corrected MEHP (B=-0.40; 95% C.I.: -0.73, -0.07, relative to the 1st tertile) and total DEHP (B=-0.39, 95% C.I.:-0.66, -0.01 for the 2nd tertile and B=0.34, 95% C.I.: -0.67, -0.01 for the 3rd tertile, relative to the 1st tertile) with a linear trend among girls. MBzP was also found negatively associated with bone age/chronological age ratio (B=-0.07, 95% CI: -0.13, -0.01 for the 3rd tertile, relative to the 1st tertile) with a linear trend for girls. We found no evidence of an association between phthalate exposure and ovarian volume or testicle size. This analysis suggests phthalate exposure may affect specific pubertal development characteristics in human beings. Further studies with larger sample sizes and longer follow-up period are warranted. Copyright © 2014. Published by Elsevier Inc.
    Environmental Research 11/2014; 136C:324-330. DOI:10.1016/j.envres.2014.10.026 · 3.95 Impact Factor