Iron Plaque Prevents Partitioning of Polycyclic Aromatic Hydrocarbons on Rice (Oryza sativa) Root Surface

Adsorption of polycyclic aromatic hydrocarbons (PAHs) on root surfaces has essential impacts on PAH phytoremediation. An Fe plaque is commonly formed on the root surface of aquatic plants. Therefore, it is worth investigating the impact of the Fe plaque on PAH adsorption on rice root surfaces. Using Bayesian linear water-methanol cosolvent models, we estimated accurate water-biosorbent partition coefficient values for phenanthrene, pyrene, and benzo[a]pyrene between water and rice root biosorbent fractions, including rice root materials with Fe plaque, removed Fe plaque, and removed Fe plaque and lipids. Our results showed that Fe plaque inhibited the adsorption of PAHs on rice root surface; the inhibition impacts increased with hydrophobicity of PAHs. This result highlights the need for considering the impact of Fe plaque on PAH adsorption during phytoremediation. Integr Environ Assess Manag 2020;16:392-399. © 2020 SETAC.