Uptake of SO2(g) was measured as a function of sulfuric acid concentration in the range pH=1 to 70 wt% H2SO4 at 293 K. Uptake studies were carried out in the presence of solvated H2O2, O3, HONO, NO2, and HNO3. The studies yielded Henry's law coefficients for SO2 which were in accord with previous measurements. The results provided first time determinations at high acidities of rate coefficients for the reaction of SO2 with H2O2, O3, and HONO in the solvated state. The observed SO2(g) uptake was consistent with bulk phase oxidation processes. The measured rate coefficients were used to evaluate the role of heterogeneous interactions with the selected species for aerosol formation in aircraft plumes. Calculations show that these interactions are insignificant compared to gas phase oxidation by the OH radical. ¿ 2000 American Geophysical Union