Exposure to air pollutants agents, like sulfur dioxide (SO 2 ), has significant effects on the cardiovascular system.Studies have shown that SO 2 blocks I CaL and increases the I Na , I K1 and I to currents, which implies action potential duration (APD) decrease, favoring the initiation of atrial arrhythmias.This study aims to assess the effects of the SO 2 at different concentrations on human atrial action potential, using computational simulation.For this, based on experimental data, we developed concentration-dependent equations to simulate the SO 2 effects on the currents.They were incorporated in the Courtemanche model of human atrial cell and in a 2D model of atrial tissue.S1-S2 cross-field protocol was applied to initiate a rotor.SO 2 concentrations from 0 to 100 µM were implemented.Our results are in agreement with results from non-human in vitro and in vivo studies.The SO 2 causes APD shortening and loss of plateau phase in a fraction that increases as the concentration increases.In the 2D model, a rotor can be generated from 50 µM of SO 2 concentration, showing a proarrhythmic effect.