Risk assessment of potentially toxic elements in agricultural soils and bioconcentration in rice grains from Faridkot District, India

Abstract

Potentially toxic elements (PTEs) in soil pose significant risks to both ecology and human health. Therefore, to understand the effect of PTEs in agricultural soils of Faridkot District, Punjab, India, 36 soil samples were analyzed for physicochemical properties, contents of PTEs (aluminum, arsenic, nickel, boron, uranium, barium, chromium, cadmium, copper, iron, lead, cobalt, manganese, selenium, and zinc), possible ecological and human health risks and bioconcentration in rice grains. Soils showed high mean contents (mg/kg) of potassium (906.65), sodium (760.78), and chlorides (247.13) with cadmium, copper, zinc, arsenic, and selenium contents (mg/kg) in 55.56%, 33.33%, 25.00%, 16.67%, and 13.89% of samples exceeding their safe limits (0.06, 20.00, 50.00, 20.00, and 0.20, respectively). Individual and multi-element indices suggested extremely high-soil enrichment of arsenic, cadmium, and selenium and low to moderate ecological risk. Multivariate analyses revealed the contribution of both geogenic and anthropogenic activities to soil contamination. Mean bioconcentration factors of chromium (4.48), boron (1.24), and copper (2.69) were >1.00 in rice. Residents had higher cancer risk (TCR) due to arsenic (3.64E-05) and chromium (4.04E-06) in soil, mainly through ingestion and dermal contact. This work could serve as baseline database for further research and designing the strategy to alleviate soil contamination.