Estrogenic potencies

Post-coital activity in the rat was on the same order as estrogenic potency, with the order being CDB-1357 (ED jqo = (3 //g/kg)/d for each of5days) >... 

Petit F, Le Goff P, Cravedi JP, et al. 1997. Two complementary bioassays for screening the estrogenic potency of xenobiotics Recombinant yeast for trout estrogen receptor and trout hepatoc5fte cultures. J Molecular Endocrinology 19 321-335. 

Harries, J.E., Janbakhsh, A., and Jobling, S. et al. (1999). Estrogenic potency of effluent from two sewage treatment works in the United Kingdom. Environmental Toxicology and Chemistry 18, 932-937. 

Pelissero, C., Flouriot, G., and Foucher, J.L. (1993). Vitellogenin Synthesis in Cultured-Hepatocytes—an in vitro Test for the Estrogenic Potency of Chemicals. Journal of Steroid Biochemistry and Molecular Biology 44, 263-272. 

Table 3 Relative estrogenic potencies as determined by different bioassays (expressed as EEF - the molar-based 17/5-estradiol equivalency factor) (adapted from [51])... 

In the Environment Canada distributional approach to characterise risks of NP, NPEO, and NPEC [8], relative toxicities were proposed based on categorising acute and chronic toxicities. A similar approach was used in that study to provide relative estrogenic potencies. Both are listed in Table 7.3.2 (Chapter 7.3). 

Brominated bisphenol A compounds with the lowest degree of bromination showed the highest estrogenic potencies (EC50 value of 0.5 pM for 3-monobromobi-sphenol A). 

Note Estrogenic potency of the compounds was measured using a recombinant yeast cell bioassay. 

Pelissero, C., G. Flouriot, J.L. Foucher, et al. 1993. Vitellogenin synthesis in cultured hepatocytes an in vitro test for the estrogenic potency of chemicals. J. Steroid Biochem. Mol. Biol. 44 263-272. 

Kerdivel, G., Le Guevel, R., Habauzit, D., Brion, F., Ait-Aissa, S. Estrogenic potency of benzophenone UV filters in breast cancer cells proliferative and transcriptional activity substantiated by docking analysis. PLoS One 8(4), e60567 (2013)... 

Over the last decades, large amounts of different man-made chemicals which can act as weak estrogens have been released into the terrestrial and aquatic environment and are distributed world-wide. Classical environmental estrogens are pesticides, such as o,p -DDT, and its metabohtes o,p -DDE and o,p -DDD, methoxychlor and its metabolites, chlordecone (Kepone ), dieldrin, Toxaphene, and endosulfan [126, 135, 136]. It is also known that many chemicals with very weak or no measurable estrogenic activity can be metabolized in organisms especially to hydroxylated compounds which may have much more estrogenic potency than the parent compound. Examples are methoxychlor and its mono- and di-demethylated derivatives [126,127] as well as the alkylphenol... 

Some polychlorinated biphenyls, especially their non-planar para-hydroxylat-ed metabolites also possess estrogenic activity [126,135,140]. These metabolites have a higher estrogenic potency than their parent compounds. Some co-planar polychlorinated biphenyls (PCB 77 and PCB 126) have been shown in vivo to have estrogenic as well as antiestrogenic activities, probably solely through hydroxy metabolites (NIH shift to para). This reinforces the European view that EDCs can only be confirmed in intact animals. It is also known that some hydroxylated metabolites of polycyclic aromatic hydrocarbons (PAHs), e.g. 3,9-dihydroxybenzo[a]anthracene, show estrogenic activity [141 -143]. 

Tetrabromobisphenol-A showed no estrogenic effects in an eucaryotic test system (K. Rehmann personal communication 1996). However, Korner et al. [138a] found estrogenic potency of this chemical in the proliferation assay with the MCF-cell line (purity of TBBA 97%). 

Relative estrogenic potency compared to 17/i-estradiol (100) by molar mass determined with the recombinant yeast cell bioassay (RCBA) [138b]. Trade name. 

The E-isomer of the diethylstilbestrol structure (104) has 10 times the estrogenic potency of the Z-isomer this effect has been rationalized from the conclusion that the E-... 

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