Abstract

The estrogenicity of biological extracts tested by appropriate bioassay is a standard method to evaluate the total effective xenoestrogen burden (TEXB). Information has been published on the combined effect of xenoestrogens after removing endogenous hormones. The main goal of the present study was to investigate the combined estrogenicity of endogenous and xenoestrogens in human adipose tissue samples with and without HPLC fractionation. The results suggest that both approaches may be useful to study interaction between xenoestrogens and endogenous hormones. TEXB of the whole extract provides information about the overall estrogenicity to which humans are exposed, useful to assess the potential contribution to health outcomes. Additionally, it is possible to identify the source and potency of the estrogenicity by using the method with fractionation, distinguishing the effect of organohalogenated chemicals (alpha-fraction) from that of endogenous hormones and more polar xenoestrogens (beta-fraction). Both methods are an integrative measure of internal estrogen load. (C) 2011 Elsevier Inc. All rights reserved.