Association between precocious puberty and some endocrine disruptors in human plasma.

Endocrine disruptors that mimic natural hormones and inhibit the action of hormones have recently attracted attention as one of the main cause of precocious puberty. In this study, the levels of 7 EDCs and 3 isoflavones that exhibit estrogen-like actions were measured in the plasma of precocious puberty patients and compared to control subjects to determine if there is an association between the onset of precocious puberty and the levels of EDCs in the plasma. EDCs examined in this study were bisphenol-A (BPA), di(2-ethylhexyl) phthalate (DEHP), dibutyl phthalate (DBP), mono(2-ethylhexyl) phthalate (MEHP), monobutyl phthalate (MBP), n-nonyl phenol (n-NP), and t-octylphenol (t-OP), and whereas the isoflavones were equol, genistein, and diadzein. The level of MBP in the plasma of patients was 1.3 times higher than that of the controls. The levels of t-OP and n-NP in the plasma of patients were respectively 1.15 and 1.2 times higher than those of the control group. Finally, the levels of the diadzein, equol and genistein were 1.37, 1.3 and 2.67 times higher than those of the control group, and genistein showed a statistically meaningful result (P = 0.0008). The results suggest that these six substances (MBP, t-OP, n-NP, daidzein, equol, and genistein) have an effect on precocious puberty.