Exposure to environmental chemicals can affect genetic and epigenetic molecular pathways and may cause altered growth and development. Among those exposures, endocrine-disrupting chemicals (EDCs) are of particular concern as humans are abundantly exposed to these chemicals by various means in every period of life. Several well-known environmental chemicals, including phthalates and bisphenol A (BPA), are classified as EDCs. These EDCs are suggested to play roles in early onset of puberty in girls. The aim of this study is to determine plasma phthalate (di(2-ethylhexyl)phthalate [DEHP] and its main metabolite mono(2-ethylhexyl)phthalate [MEHP]) and urinary BPA levels in girls with idiopathic central precocious puberty (CPP) and peripheral precocious puberty (PPP). This study was performed on newly diagnosed idiopathic central precocious puberty (CPP) patients (n = 42) and peripheral precocious puberty (PPP) (n = 42) patients, who were admitted to Keçiören Training and Research Hospital, Clinic of Pediatric Endocrinology between August 2012 and -July 2013. Nonobese healthy girls (n = 50) were used as the control group. Urinary BPA levels were not statistically different in control, PPP and CPP groups (medians 10.91, 10.63 and 10.15 μg/g creatinine, respectively; p > 0.05). Plasma DEHP levels were significantly higher in PPP group when compared to control. Plasma MEHP levels were not significantly different in control and PPP groups (p > 0.05). However, in CPP group, both plasma DEHP and MEHP levels were significantly higher than control and PPP groups. This study showed that phthalates might play a role in the occurence of CPP in girls.

No abstract

No abstract

There is a growing concern over the timing of pubertal breast development and its possible association with exposure to endocrine disrupting chemicals (EDCs), such as bisphenol A (BPA). BPA is abundantly used to harden plastics. The aim of this study was to investigate the relation between premature thelarche (PT) and BPA by comparing the urinary BPA levels of PT girls with those of healthy subjects. Twenty-five newly diagnosed nonobese PT subjects (aged 4-8 years) who were admitted to the Pediatric Endocrinology Department at Akdeniz University were recruited. The control group composed of 25 age-matched girls without PT and other endocrine disorders. Urinary BPA levels were measured by high pressure liquid chromatography. The median urinary concentrations of BPA were found to be significantly higher in the PT group compared to the healthy control group (3.2 vs. 1.62 μg/g creatinine, p < 0.05). We observed a weak positive correlation between uterus volume and urinary BPA levels. There was a weak correlation between estradiol and urinary BPA levels ( r = 0.166; p = 0.37); and luteinizing hormone and urinary BPA levels ( r = 0.291; p = 0.08) of PT girls. Our results suggest that exposure to BPA might be one of the underlying factors of early breast development in prepubertal girls and EDCs may be considered as one of the etiological factors in the development of PT.

No abstract