The research paper is aimed to modify the human health impact assessment of Cr in soils. The current article presents the input of several critical parameters for the human health Impact Score (IShum) assessment in soils. The modification of the IShum is derived using geological data (results of neutron activation analysis of soils are used in the IShum calculation; research area is divided using the watersheds) and population size and density. Watersheds reflect the local environmental conditions of the territory unlike the administrative units due to their geological independence. The calculations of the Characterization factor value underestimate the influence of the population size and density on the final result. Default regional values cannot be considered during the assessment of the potential human health impact for the big sparsely inhabited areas. In case of very low population density the result will be overrated and underestimated in the opposite case. The current approach demonstrates the generosity of the geographical separation in the USEtox model. The same approach can be utilized for other geo zones due to the accessibility of this information (area size, population size and density, geological and landscape features).