In vitro profiling of endocrine disrupting effects of phenols.

Some phenols have been suspected to modulate the endocrine systems of wildlife and humans, but less is known about their interactions with different types of nuclear receptors. In this study, the ability of 2-tert-butylphenol, 2-isopropylphenol, 4-tert-octylphenol (4-t-OP), 2,4-dichlorophenol (2,4-DCP), 3,4-dichlorophenol (3,4-DCP), pentachlorophenol (PCP), bisphenols A (BPA), tetrabromobisphenol A (TBBPA), tetrachlorobisphenol A (TCBPA) and 4-phenylphenol to activate estrogen receptor (ER), androgen receptor (AR), progesterone receptor (PR) and estrogen-related receptor (ERR) were determined using a set of recombined yeast strains. It was found that 4-t-OP, 3,4-DCP, PCP, BPA, TBBPA, TCBPA and 4-phenylphenol were ERalpha agonists, while 4-t-OP, PCP and 4-phenylphenol showed ERalpha antagonistic activities. 2-tert-Butylphenol, 4-t-OP, 2-isopropylphenol, 2,4-DCP, 3,4-DCP, BPA, TCBPA and 4-phenylphenol were antagonists for AR, whereas none of the compounds studied were found to be an AR agonist. TCBPA, TBBPA and PCP were PR antagonists, and 2-tert-butylphenol, 3,4-DCP, 4-t-OP, 4-phenylphenol and 2-isopropylphenol were weak inhibitors on expression under control of the PR. None of the phenols were PR agonists. 2-tert-Butylphenol, 4-t-OP and PCP were ERRgamma inverse agonists, while 2,4-DCP, 3,4-DCP, PCP, BPA, TBBPA and TCBPA exhibited the ability to reverse the ERR inhibition induced by 4-hydroxytamoxifen. Based on the functional agonistic or antagonistic receptor-mediated effects, we further discussed the possible action mechanisms of these phenols as endocrine disrupting chemicals.