Introducing a method of human health risk evaluation for planning and soil quality management of heavy metal-polluted soils—An example from Grugliasco (Italy)

European governmental institutions, as well as local communities, have recently become aware of the threats arising from soil pollution for the welfare of the population. Humans contact with soils is more likely in urban than in rural areas, and is strongly dependent on land use. Spatial planning and land management may have important impacts on the potential transfer of pollutants from contaminated soils to humans. In the present study, we propose a land use-based method for the evaluation of human health risks arising from heavy metal-contaminated urban soils, addressing in particular the influence of planning measures and land use changes on such risks. The method accounts for the role of the bioavailability of soil metals as a key factor in health risk assessment. In order to increase method applicability, a step-by-step procedure and a calculation tool were elaborated. The method can be used to identify areas in which the current or planned land use is associated with unacceptable health risks and to optimise the allocation of a certain land use to areas that are well suited and where the risks are minimal. A risk index is calculated for the area, taking the land use into consideration, as the sum of the risks from different exposure pathways and different heavy metals. For those areas where risk is identified as unacceptable, alternative planning or management options should be defined to achieve a maximal risk reduction in a cost-effective way. The method is illustrated using the Italian municipality, Grugliasco.