The impact of Resonant Magnetic Perturbations (RMPs) on the edge of MAST L-mode plasmas is studied using a mid-plane reciprocating probe equipped with a Gundestrup probe head. A strong impact on the characteristics of the ion saturation current fluctuations is observed just inside the separatrix, with a broadening of the power spectrum and an asymmetrization of the probability distribution functions towards non-gaussian shapes. No major effect is found in the Scrape-Off Layer (SOL). Floating potential measurements are used to evaluate the modification of the plasma potential profiles. The radial electric field profile flattens when RMPs are applied, leading to a theoretically expected increase inside the separatrix and a decrease in the SOL. A consistent change is observed on the perpendicular and parallel flows which tend to increase inside the separatrix. On the contrary, in the SOL, a braking of the rotation is observed with the application of RMPs. All these effects occur only above a threshold in the amplitude of the current applied in the RMP coils and and are not toroidally localized.