Uptake,\nSubcellular Distribution, and Metabolism of\nDecabromodiphenyl Ethane in Vegetables under Different Exposure Scenarios

Decabromodiphenyl\nethane (DBDPE), a key alternative to deca-BDE\n(BDE-209), has been ubiquitous in the receiving ecosystem. However,\nlittle is known about its uptake process and fate in plants. Here,\nthe plant absorption, distribution, and metabolism of <sup>14</sup>C-DBDPE under two distinct exposure pathways (i.e., soil-root and\nairborne dust-leaf) were investigated with three vegetables (cherry\nradish, water spinach, and eggplant). DBDPE was absorbed and primarily\naccumulated in directly exposed roots and leaves, with translocation\nfactors to other tissues of 0.04–0.77 and 0.73–12.80\n× 10<sup>–3</sup>, respectively. DBDPE in exposed leaves\nwas more difficult to transport as most DBDPE did not enter the interior\nof the leaves but was stored in waxes (>90%). Furthermore, DBDPE\nwithin\nleaves was found to enter mostly through waxy layer penetration (>97%).\nThe majority of <sup>14</sup>C-DBDPE was localized in cell walls (52.6\nand 75.6%, respectively) and organelles (22.7 and 45.5%, respectively)\nof exposed tissues, substantially restricting its in-plant translocation.\nDebrominated products were detected in exposed roots, but barely found\nin exposed leaves, as most DBDPE was blocked by the waxy layer. Moreover,\nDBDPE was stable in soils and dust without degradation. Our findings\ncontribute to a deeper understanding of the environmental fate of\nDBDPE in soil-plant and airborne dust-plant systems.