Estrogenicity test materials

Allergic contact dermatitis from transdermal estrogen has been described in Korea, where the reaction was found to be due to 17-P-estradiol itself and not to an excipient (226). In some cases, allergic reactions and systemic contact dermatitis are clearly attributable to the patch material or to excipients. Even natural estradiol given in this way can occasionally cause hypersensitivity reactions, as determined by patch tests (227). 

Bisphenol-A (BPA) is used in the manufacture of epoxy resins and polycarbonate plastics. These compounds are then used in the manufacture of various other products, including tooth fillings, dental materials, and the coatings on the inside of food tins. BPA was identified as an estrogen mimic after tests with yeast conditioned media (see Figure 3). 

Fig. 3. Effect of estrogen on uptake of uridine-Tl by the uterus and its incorporation into acid-insoluble material and nuclear RNA. The data are expressed as percent of control value. Brackets show the ranges of triplicate experiments. Five uteri were pooled for each experimental or control group. The control values are 6920 cpm/mg homogenate DNA 11.0% acid-insoluble radioactivity and 1204 cpm/mg nuclear RNA. For each period of time tested for estrogen action, separate control experiments were performed. Thus the control values given here at time zero for tissue radioactivity and nuclear RNA specific activity, and for acid-insoluble radioactivity represent, respectively, the mean for 15 control groups (i.e., three for each time period of estrogen action tested). From Means and Hamilton (1966).

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