A novel electron beam irradiation process has proven to be effective in removing thioanisole (methyl phenyl sulfide, CH3S−C6H5) from aqueous solutions. This paper presents substrate destruction data at pH 5 and pH 9. To apply a kinetic model, which predicts removal efficiencies, overall rate constants for reactions of thioanisole with •OH radicals, hydrated electrons, and hydrogen atoms were newly measured or carefully re-determined by pulse radiolysis. The respective values are (9.90 ± 0.13) × 109, (3.1 ± 0.1) × 108, and (3.24 ± 0.08) × 109 (M s)-1. Comparison of the model predictions to the experimental results revealed a very good agreement at pH 5 and an overestimation of the removal at pH 9. The presence of an additional scavenger at pH 9 but not at pH 5 reacting with •OH radicals, hydrated electrons and hydrogen atoms is considered to be responsible for the decrease in removal efficiency.