Assimilation behaviors and metabolite formations of estrone sulfate sodium (E1-3S) and 17β-estradiol-3-O-sulfate sodium (E2-3S) in the wheat.

The conjugated steroid estrogens (CSEs), including estrone sulfate sodium (E1-3 S) and 17β-estradiol-3-O-sulfate sodium (E2-3 S), exhibit distinct metabolic behaviors in the aqueous and soil environments. However, their assimilation behaviors and metabolite formations in plant bodies (shoots and roots) remain poorly understood. Therefore, this study used a modified plant hydroponic system to explore the efficiency with which wheat (Triticum acstivnm L.) assimilated the two estrogen conjugates, E1-3 S and E2-3 S. Results indicated the potential of wheat to absorb E1-3 S and E2-3 S, with their assimilation in the root being significantly higher (10-10 ng/g dw) than in the shoot (10-10 ng/g dw). E1-3 S de-sulfated and transformed to estrone (E1) at a rate of 4%-45% in the root's oxidative environment, whereas E2-3 S converted to E1-3 S at 210%-570%. However, the root-to-shoot transfer was impeded by a less potent metabolic activity within the shoot system. The co-exposure treatment revealed that E1 or 17β-estradiol (E2) affects the assimilation of E1-3 S and E2-3 S by wheat, with E1 inhibiting E1-3 S assimilation and E2 promoting E2-3 S assimilation in wheat bodies. Nonetheless, free-form steroid estrogens (FSEs), which typically have a significant hormone action, can oxidative-damage the wheat tissues, producing a progressive wilting of wheat leaf and so limiting the transpiration process. Co-exposure initially increased the assimilation amounts of E1-3 S (particularly in shoots) and E2-3 S (in both roots and shoots), but these values rapidly declined as exposure duration increased. The combined effects of E1-3 S and E2-3 S exposure also increased their assimilation. These findings suggest the need for further investigation into the cumulative impact of environmental estrogen contaminants. The findings of present study can potentially guide the development of strategies to prevent and manage steroid estrogen contamination in agricultural contexts.