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While pollution of the environment by polycyclic aromatic hydrocarbons has been rather well studied, the fate of substituted polycyclic aromatic hydrocarbons in ecosystems is less understood, notably in soil–plant systems. Here we hypothesized that substituted polycyclic aromatic hydrocarbons could enter wheat and induce phytotoxicity. We studied the accumulation, root-shoot translocation and phytotoxicity of α-tetralone, 1-nitronaphthalene, 1-nitropyrene, and 7,12-dimethylbenz[a]anthracene in wheat using hydroponic experiments. We deciphered the accumulation and translocation mechanisms by inhibition with sodium vanadate, glycerol and silver nitrate. Results show that pollutant concentrations increased rapidly in roots, reaching maximum of 38.3 μg/g for α-tetralone, 268.7 μg/g for 1-nitronaphthalene, 3566.1 μg/g for 1-nitropyrene, and 3632.7 μg/g for 7,12-dimethylbenz[a]anthracene. In contrast, the root-shoot translocation factors of α-tetralone, 1-nitronaphthalene, 1-nitropyrene and 7,12-dimethylbenz[a]anthracene were 2.4, 1.6, 0.1, and 0.1, respectively, thus decreasing significantly with increasing compound hydrophobicity. This could be explained by preferential adsorption for hydrophobic compounds, whereas less hydrophobic compounds could be partly translocated in a soluble form through plant water channels. The accumulated substituted polycyclic aromatic hydrocarbons in wheat induced the decrease of the total chlorophyll contents by 19.0–30.1%, yet did not cause lipid peroxidation damage. Overall, our findings indicates the bioaccumulation potential and toxicity of substituted polycyclic aromatic hydrocarbons in terrestrial plants. [ABSTRACT FROM AUTHOR]