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This study investigated the impact of artificial root exudates (ARE) and different root exudate components (RECs), including organic acids, amino acids, and saccharides, on the availability of phenanthrene as a representative of polycyclic aromatic hydrocarbons (PAHs) in soil (TypicPaleudalfs) using laboratory batch assays.An n-butanol extraction procedure and a sorption-desorption experiment were used to predict the availability of phenanthrene in soil.We found that the n-butanol extractable amounts of phenanthrene in soil increased with increasing ARE and REC concentrations.The extractability of phenanthrene in soil with various treatments decreased in the following order: citric acid > oxalic acid > ARE > malic acid > alanine > serine > fructose treatments.Organic acid and ARE resulted in the most significant increase in PAH extractability by soil.Phenanthrene sorption by soil could be described using a linear model, regardless of the presence of ARE or RECs.The simulated distribution constants (Kd) and carbon-normalized distribution constants (Koc) for phenanthrene sorption decreased significantly with the addition of all test REs.Organic acid and ARE enhanced desorption of phenanthrene from soil.In contrast, lower concentrations of test amino acids promoted phenanthrene desorption, while higher concentrations inhibited desorption.Fructose had a minimal effect on PAH desorption.The mechanism of REC-influenced availability of PAH in soil is discussed based on the observed metal dissolution, soil organic matter reduction, and dissolved organic matter release from soil solids.