Probabilistic-fuzzy risk assessment and source analysis of heavy metals in soil considering uncertainty: A case study of Jinling Reservoir in China

Abstract

Considering the uncertainty caused by the random error of the sample measurement, the heterogeneity of spatial and temporal distribution of pollutants, and the traditional method of selecting a single parameter for evaluation, based on fuzzy theory, Hakanson potential ecological risk index (considering heavy metal enrichment, ecotoxicity and bioavailability) and United States Environmental Protection Agency health risk assessment system, the fuzzy ecological risk and health risk assessment methods for of heavy metals in soil were established. In the soil of the Jinling Reservoir area, Cd, which has high bioavailability, had the highest average contribution rate to RI, and thus was, regarded as a priority metal for ecological risk. Sites JL9 and JL11 were the priority areas. The heavy metals did not pose a clear hazard to human health, but children had a higher health risk. Pb and As were regarded as the priority metals for health risk. Fuzzy evaluation provided the risk interval and membership degree, contained more parameter information, quantified and reduced the uncertainty of parameters, provided more comprehensive results, and compensated for the deficiency of deterministic evaluation. As the main source of heavy metals, the intensity of agricultural activities in the study area must be controlled to avoid excessive input and accumulation of heavy metals, which may damage the ecological environment and endanger human health.