Estrogenic Activity of Alkyl(thio)phenols and 4,4'-thiodiphenol Formed from Degradation of Commercial Insecticides

抄録

We investigated the estrogenic activity of commercial insecticides fenamiphos, fenthion, methiocarb, propaphos, sulprophos, and temephos as well as some phenolic compounds obtained as a result of their degradation. Using a yeast two-hybrid assay, the relative activities of 4-(methylthio)phenol, 3-methyl-4-(methylthio)phenol, 3,5-dimethyl-4-(methylthio)phenol, and 4,4'-thiodiphenol (TDP) were evaluated as 11, 10, 4, and 1000% (10 times) that of bisphenol-A. To reveal the binding abilities of the abovementioned phenolic compounds with respect to human estrogen receptor α (hERα), we carried out ER-ELISA and found that all compounds had significant abilities, particularly, TDP. From the viewpoint of bioisosterism, we discussed the similarity between a vinylene-group, -CH=CH-, and a thioether-group, -S-. We suggest that an alkylthio-group substituted at the “para”-position of a phenol ring plays a key role in the binding abilities of the investigated phenolic compounds.