We use critical load modelling to assess the risks caused by diffuse Cd and Pb pollution on two sites located on forest and arable lands respectively. The objectives of this work are: (i) to test the proposed critical load method on arable land and, (ii) to compare critical loads with current measured Cd and Pb fluxes. For the two sites, computed critical concentrations of Cd and Pb in soil water regarding the protection of soil organisms (2.3 and 4.9 mg.m-3 respectively for the forest, 0.7 and 4.5 mg.m-3 respectively for the arable site) are above current concentrations. Modelled critical loads (15.6 and 46.4 g.ha-1.a-1 for Cd and Pb respectively) are lower than current inputs for the forested site. However the arable site would be in exceedance with current inputs larger than modelled critical loads (1.3 and 7.1 g.ha-1.a-1 for Cd and Pb respectively). These results are going to be checked thanks to long-term monitoring and ecotoxicological tests.