| Summary: | Toxaphene is the most abundant persistent organic pollutant in the Arctic and in the Great Lakes. Toxaphene technical mixture (Tox) applied as a pesticide consists of over 800 congeners. Through processes of environmental degradation, selected metabolism, and bioaccumulation, 2 congeners are prominent in humans; 2-exo,3-endo,5-exo,6-endo,8,8,10,10-octachlorobornane (T2) and 2-exo,3-endo,5-exo,6-endo,8,8,9,10,10-nonachlorocamphene (T12). The MCF7-E3 human breast cancer cell model was used to screen for the estrogenic activities of Tox, T2, and T12. A concentration of 10muM was required by all 3 compounds to elicit an estrogenic response (a proliferative effect (PE) upon the cells). The congeners however, showed slightly different PEs from Tox. Both T2 and T12 had a lower PE than Tox, and T2 had a higher PE than T12. Results from binary combination studies showed that effects of Tox, T2, and T12 were additive. Tox, T2, and T12 had no significant effects on estrogen receptor and progesterone receptor levels. It was shown that the environmental prevalent congeners had lower estrogenic activities than Tox and there is no synergistic effect.
|
|---|