Assessment of potentially toxic heavy metal contamination in agricultural fields, sediment, and water from an abandoned chromite-asbestos mine waste of Roro hill, Chaibasa, India

The major aim of the present study is to assess (1) depth-wise physico-chemical characteristics and pseudo-total metal concentrations in the abandoned chromite-asbestos mine waste, contaminated agricultural soil, and control agriculture soil; (2) degree of soil contamination and metal geoaccumulation index in agricultural soil; and (3) concentrations of metal in the sediment and water samples of river, tributary, and different water bodies located in the vicinity of an abandoned chromite-asbestos mine of Roro hill. Nutrient content and physical properties of the mine waste were found low and poor. Pseudo-total metal concentrations in the mine waste were found in the order of Cr > Ni > Mn > Cu > Pb > Co > Zn > Cd. High concentrations of Cr (1148 mg kg⁻¹) and Ni (1120 mg kg⁻¹) were found in the contaminated agricultural soils which far exceed the soil threshold limits. The contamination factor and geoaccumulation index in the agricultural soils were found high and decreased with increase in depth for Cr and Ni, indicating strong contamination. Concentrations of Zn, Mn, Co, Cu, Pb, and Cd were found low and within toxicity limit. Further, metal grouping and site grouping cluster analysis also revealed that Cr and Ni are closely linked with each other and chromite-asbestos mine waste was the major source of contamination. Sediment samples were found high in metal content and decreased with increase in distance and mine waste influence. Water flowing from the mine adit was found high in Cr and Ni concentration (above critical drinking water total concentration). Further research is required to study the pollution factors for sediment and water samples and metal accumulation pattern in naturally growing plants and locally practised crops to access its impact on human and livestock.