Methods for xenoestrogen testing

Research in our laboratories has focused on development of a battery of in vivo and in vitro bioassays for determining estrogenic activity and potency of different classes of natural and synthetic industrial-derived estrogeni c compounds (xenoestrogens) including food/beverage extracts, phytoestrogen s, phenolic compounds, organochlorine pesticides and pollutants. For many o f the weak estrogenic compounds, their activity as estrogen receptor (ER) a gonists or antagonists is dependent on the gene/gene promoter, cell context and expression of ERalpha or ERbeta isoform. For example, extracts of red wine, bound to the ER, exhibited estrogenic activity in T47D, MCF-7 (breast ) and Hep G2 (liver) human cancer cell lines, whereas reconstituted organoc hlorine pesticide residues found in food were active only in Hep G2 cells t hat transiently expressed ERalpha or ERbeta. The relative potencies of red wine extracts versus reconstituted organochlorine pesticides were assay-dep endent; however, estrogen equivalent daily intakes from a glass of red wine (similar to 0.5-2 mu g estrogen equivalents/day) were at least 10(3) highe r than observed for the reconstituted organochlorine pesticide mixtures. Ri sk assessment of xenoestrogens and other synthetic chemicals which modulate endocrine responses must take into account high dietary levels of natural products in food, drugs and health food store extracts which also modulate endocrine responses. (C) 1998 Elsevier Science Ireland Ltd. All rights rese rved.