Ozone solubilities in aqueous solutions containing phosphate buffers and tert-butyl alcohol have been measured in the ranges 0 < I < 0.48 M, 18 degrees C < T < 42 degrees C, and 2 < pH < 6. The experimental method adopted accounts for the reaction of ozone self-decomposition, by evaluating the relevant rate constant for each experiment. The results obtained at constant pH can be coherently explained in terms of a salting-out effect. In contrast, a rather complex behavior has been observed when changing the pH. This effect can be tentatively explained when accounting for the detailed composition of the solutions and for the activity coefficients of the ionic species.