Heavy Metal Pollution of Agricultural Soils and Health Implications at Korsimoro Market Gardening Sites

Abstract

In order to assess pollution, health risks to humans, and quantitatively determine the sources of heavy metal inputs into cultivated soils, a total of 41 soil samples were collected in the Korsimoro market gardening area between March 2022 and April 2022. Various indices, including the geoaccumulation index (Igeo) and the potential ecological risk index (RI), were used to analyze pollution levels caused by heavy metals. Health risk assessments defined by the US Environmental Protection Agency were applied to analyze risks to human health and identify sources of heavy metals. The results showed that the average concentrations of Ni, Cd, Co, Mn, Se, and Hg exceeded the limits set by the WHO/FAO, with the exception of Cu, As, Pb, Zn, and Cr. The geoaccumulation index (Igéo) indicates very high soil pollution caused by Cd (11.91), Co (5.09), Se (6.61) and Hg (6.71), zero pollution levels for Ni (0.86), Pb (-0.37), Zn (0.10) and Mn (0.68), and moderate pollution levels associated with Cu (1.30), As (1.88) and Cr (1.06). The potential ecological risk index showed that the majority of heavy metals contributed to a very high level of potential ecological risk (RI= 189082.76). This pollution therefore reveals a very high level of contamination associated with anthropogenic activities. According to the results of the health risk assessment, the carcinogenic and non-carcinogenic risks to human health associated with heavy metals far exceed the threshold for significant risk. This study improves our understanding of heavy metal pollution levels in the soils of the study area and also serves as a reference for attributing sources of pollution in other regions.